I-NRLF B 14 175 7flfl f L UNIVERSITY \. CALIFORNIA v/ LEr LILRARY fiMTTH SCIENCES LIBRARY -BO REESE LIBRARY OF TUB UNIVERSITY OF CALIFORNIA. Received ^O^LM / , 188 ' Accessions No^.4f:^^Jb Shelf No. Jb ^ MANUAL MINERALOGY NATURAL HISTORY MINERAL KINGDOM, CONTAINING GENERAL INTRODUCTION TO THE SCIENCE, AND DESCRIPTIONS OF THE SEPARATE SPECIES, INCLUDING THE MORE RECENT DISCOVERIES AND CHEMICAL ANALYSES. JAMES NICOL, F.B.8.E., F.G.8. ASSISTANT SECRETARY OP THE GEOLOGICAL SOCIETY. x. *T> ttUNIVERSIT EDINBURGH: ADAM AND CHARLES BLACK, NORTH BRIDGE ; LONGMAN, BROWN, GREEN, AND LONGMANS, LONDON. MDCCCXLIX. US SCIENCE' LIBRARY V PREFACE. MINERALOGY has recently made rapid progress in every depart- ment. The forms of crystals are now better understood, and their dependence on each other, and on the axes of the systems, are more accurately determined, and expressed in simpler and clearer language, than a few years ago might have been considered pos- sible. Many additions have also been made to our knowledge of the physical properties of minerals, especially their relations to the subtler agents, light, electricity, magnetism, enlarging the bounds and heightening the interest of the study. The number of exact chemical analyses has likewise greatly increased, con- firming or correcting the views formerly entertained of the con- stitution of many important species. These analyses, too, are interpreted in a more intelligible manner, and their results exhi- bited in definite formulae. Hence the value of the Science is much extended, and its true place in the Natural History of the Earth fully vindicated. No geologist, without a knowledge of its principles, can now pretend to explain the nature or formation of the igneous and crystalline rocks, rocks covering more than a fifth part of the surface of Britain, and probably an equal propor- tion of the whole dry land on the globe. It is clearly seen that the chemical characters, the geognostic position, the modes of association of simple minerals, must be thoroughly studied, before we can hope to solve many of the highest problems in geology. The theory of metamorphism, whether from igneous action, or IV PREFACE. the more gradual but not less certain or efficacious agency of chemical and electric forces ; the origin of mineral veins, with the manner in which they have been filled, and the various ores, or other substances, collected and arranged in them ; the sources whence plants, and through them animals, derive that unfailing supply of mineral substances needed for their growth and health- ful development, so that fertility and life are diffused over the earth ; these and many other interesting questions must ever remain obscure without a due acquaintance with this department in the History of Nature. In preparing this Manual, the Author has endeavoured to bear these facts in mind, and to give such a view of the present state of the science as might be required for the general purposes of the student, or serve as an introduction to the further investigation of some particular department. It has been his wish to treat of each portion with that fulness which its importance might require, and especially to establish the true crystallographic and chemical character of the species. The former is illustrated by numerous figures ; the latter by a more complete series of the best and most recent analyses than is to be found, he believes, in any other English work on Mineralogy. In this attempt he has been greatly aided by the labours of several of his predecessors. Though special references to these have -frequently been made, he deems it but justice again to acknowledge his obligations to Naumann, Mohs, G. Rose, Haidinger, in the crystallographic and introductory part of his work; to Rammelsberg in the chemical cha- racters and analyses of minerals ; to Weiss and Hartmann for the classification adopted ; and to the writings of these authors, of Jameson, Phillips, Allan, and especially the very elaborate treatise of Hausmann, for much information on the general history, the mode of occurrence, and the geognostic and geographical position of the various species. The titles of these and some other of the more important books consulted are given in the subjoined list, PREFACE. V which may be useful to the student who wishes to pursue the subject further. The Author regrets that the limits of this list do not admit of particular reference to numerous Memoirs scattered through the Transactions of learned Societies, and Scientific Pe- riodicals, from which much valuable information has been derived. In a work of such extent, containing so many numbers, and in which almost every word expresses a definite fact, errors can scarcely be avoided. The Author has endeavoured to diminisli their number by careful and repeated revision, and trusts that those overlooked may be found comparatively few, and not such as to interfere with the utility of the volume. He would gladly hope that, with all its defects, the work may in some measure aid in promoting the study of this branch of science, and in extending the knowledge of those wonders of Creative Wisdom with which the Mineral Kingdom, like every other portion of Nature, so richly abounds. LONDON, 20& March 1849. LIST OF WOKKS ON MINEKALO< Hauy, Traite de Mineralogie, sec. Edit. 4 vols. Paris, 1822. Mohs, Grundriss der Mineralogie, 2 Parts. Dresden, 1822. Leichtfassliche Anfangsgriinde der Naturgeschichte des Mineralreiches, 2d. Edit. Vienna, 1836, 1839. Jameson, Manual of Mineralogy. Edinburgh, 1824. Manual of Mineralogy (from the Encyclopaedia Britannica). Edin., 1837. Phillips, Elementary Introduction to Mineralogy, London, 1823 ; Edited by Robert Allan, London, 1837 ; By Alger, Boston, 1844. Haidinger, Treatise on Mineralogy, from the German of Mohs. Edin., 1825. Handbuch der bestimmenden Mineralogie. Vienna, 1845, 1846. Allan, Manual of Mineralogy. Edinburgh, 1834. v. K obeli, Grundziige der Mineralogie. Nurnberg, 1838. Glocker, Grundriss der Mineralogie. Nurnberg, 1839. Hartmann, Handbuch der Mineralogie, 2 vols. Weimar, 1843. Dana, System of Mineralogy. New York, 1844. Dufrenoy, Traite de Mineralogie, 3 vols. Paris. 1845. Hausmann, Handbuch der Mineralogie, 2 vols. Gottingen, 1845, &c. Naumann, Elemente der Mineralogie. Leipzig, 1846. Rammelsberg, Handworterbuch des chemischen Theiles der Mineralogie Berlin, 1841. Supplemente, 1843, 1845, 1847. CONTENTS. Page INTRODUCTION. Divisions of Natural History, 1 Mineralogy defined, % .2 PART I. TERMINOLOGY. CHAP. I. Form of Minerals, . .4 Crystalline and amorphous, . . 4 Crystals, faces, axes, . , .4 Systems of Crystallization, , t 5 Holohedric and Hemihedric, . . 7 Tesseral System, ... 8 Derivation of Forms, , , .10 Semitesseral Forms, . m 13 Combinations, , , .15 Tetragonal System, . . . 18 Hexagonal System, . . .22 Rhombohedral forms, . 24 Rhombic System, . . ,26 Monoclinohedric System, . . 30 Triclinohedric System, . . 32 Imperfections of Crystals, . , 33 Hemimorphism, . . ,34 Striation, t 34 Drusy surfaces, . .35 Unsymmetric, ... 35 Constancy of angular dimensions, . . 35 Goniometer and measurement of crystals, . 36 Common Goniometer, . . ,36 Reflecting Goniometer, . , 37 lii CONTENTS. Page Macles or Twin crystals, . . ,39 Tesseral macles, . . . . 40 Tetragonal, . . . .41 Hexagonal and Rhombohedric, . . 41 Rhombic, . . . .42 Monoclinohedric and Triclinohedric, . 44 Irregular aggregation of Crystals, . . 46 Polysynthetic crystals, . .- 46 Union of distinct minerals, . . 46 Forms of Crystalline aggregates, . . 47 Groups and Druses, . . . 48 Texture of Rock masses, . . .49 Psexidomorphism, ... SO Haidinger's theory, . . .51 Petrifaction, . . . 51 Mineralization, . . .52 CHAP. II. Physical Properties of Minerals. Cleavage, ... 53 In the different Systems of Crystals, . . 54 Fracture, ... 55 Hardness Mohs' scale of, . . 55 Tenacity Frangibility, . . 56 Specific gravity, . . .57 Nicholson's areometer, . , 57 Optical properties of minerals, . . 58 Transparency, ... 58 Double Refraction, , . . .59 Polarization of light, . . 60 Polarizing instrument, . . .61 Monoaxial and Binaxial, . . 63 Coloured Rings, . . ,63 Pleochroism, ... 64 Opalescence Iridescence, . . .65 Lustre and Colour, ... 65 Metallic and non-metallic, . . 65 Lustre, kinds of, . . 66 Colour, . . 66 Werner's Classification of Colours, . 67 Accidental Colours, . . .70 Tarnish, . . 70 Phosphorescence, . .71 Electricity, . . . 71 Analogue and Antilogue poles, Magnetism, . . 73 Heat, . .73 CONTENTS. IX Page CHAP. III. Chemical Properties of Minerals. Composition of minerals, . * .74 Elements, . . 74 Chemical Symbols, . .75 Table of Elements and their Atomic weights, . 76 Combinations, . .77 Table of Oxygen compounds, V' ^ Influence of composition on the external character of minerals, 80 Elemens mineralisateurs and mineralisables, . 80 Dimorphism, . . . .81 Isomorphism, . . . 81 Isomorphic substances, . . .82 Polymerous isomorphism, . . Chemical reaction of minerals, . 84 Use of the Blowpipe, . . 84 Scale of Fusibility, . . .86 Chemical reagents, ... 86 Action of Acids, . .87 Reaction of Non-Metallic Elements. Nitric acid Sulphur, . . .88 Phosphoric acid Selenium Chlorine Iodine, . 89 Bromine Fluorine Boracic acid Carbon Silica, . 90 Alkalies and Earths. Ammonia Soda Lithia Potassa Baryta, . 91 Strontia Lime Magnesia Alumina, . . 92 Glucina Yttria Zirconia Thorina, . 93 Metals. Arsenic Antimony, . . .93 Bismuth Tellurium Mercury Zinc Tin Lead, 94 Cadmium Manganese Cobalt Nickel Copper, . 95 Silver Gold, . . . 96 Platinum Osmium Palladium Rhodium, . 96 Cerium Iron Chromium Vanadium, . 97 Uranium Molybdenum Tungsten Tantalium Titanium, 98 CHAP. IV. Classification of Minerals. Mineral Species, ... 99 Mohs' System External Characters, . .100 Berzelius' System Chemical, . . 101 Mixed Systems, . . .102 System of Weiss, . 102 Table of Classification, . . .104 CONTENTS. Page Description of Species, . . . 105 Nomenclature, . . , . .106 PART II. DESCRIPTION OF SPECIES, . .109 (For Tabular View of Arrangement of Minerals, see p. xi.) Chemical Classification of Minerals, . . 527 Index of Mineral Species, . :, 559 ERRATA. Page 28, line IT, form read n. Page 42, line 1,/or R, read osR. Page 347, line 17, for much read no. Page 373, line 26, dele Nickeline, Beudant;' and in head-line of same page, for NICKELINE, read NICKEL-OCHRE. TABULAE VIEW OP THE ARRANGEMENT OF MINERALS, AND OP THEIR MORE IMPORTANT CHARACTERS, INTENDED TO FACILITATE THE DISCOVERY OF THE NAMES OP SPECIES. Note. The following table being designed to serve as a guide to the full descriptions in the work, and not to supersede reference to these, only the more prominent points have been selected. More would have been unneces- sary repetition, greatly increasing the bulk of the table, and consequently les- sening its utility. The number prefixed to each name is that under which the species is described. In the second column, the crystal-system, or the massive or amorphous character of the species, is given ; Rhdr means rhombohedric ; rh. or rhm, rhombic ; the other abbreviations require no explanation. The third column contains the hardness, the fourth the specific gravity. The fifth has reference to the action of acids, and the sixth to the effects of heat applied by the blowpipe. The following abbreviations are employed in these columns : ACIDS. ACIDS. Sol. = soluble Ins. = insoluble Af. = affected Ef. = effervesces Gel. = gelatinizes n. = nitric acid h. -= hydrochloric s. = sulphuric ncL = nitro-chloric pot. = solution of potash wtr. = water con. = concentrated w. = warm ! = very, or, great Imp. *= imperfectly Pul. = pulverized Ig, = when ignited Sil. = leaves silica BLOWPIPE. BLOWPIPE. Fus. = fusible Inf. = infusible Int. = intumesces Dcr. = decrepitates Wtns. becomes white Eas. = easily Dif. = difficultly Edg. = on the edges Exf. = exfoliates En. = forms an Vol. = volatilizes Gls. = a glass Sub. = sublimes Fms. = gives out fumes Bed. = is reduced Phos. = phosphoresces Cl.fl. -* colours the flame Bkns. = blackens Hep. = an hepatic mass Crst. = crystallized Mag. = magnetic Ars. = arsenious fumes Sul. = sulphurous fumes Ant. = antimonious xii TABULAR VIEW OF THE I. ORDER OXIDIZED STONES. NAME. Crystal- lization. Hard- ness. Specific Gravity. Acids. Blowpipe. I. FAM. QUARTZ. I Quartz Rhdr. 7* 5-56-6 6 6 66-5 I 56 } 6 6 6 6-5 6-57 66-5 66-5 57 55-5 5-5 5-56 5? 5-56 55-5 5-56 55-5 66-5 56 6 3-54 55-5 6 3-54 1 2 56 2-65 22-2 2-532-6 2-57, 2-6 2-62-7 2-73 2-662-7 2-682-74 2-69 2-72-76 2-642-66 2-42-5 3-073-2 2-382-4 2-872-9 2-22-4 2-62-8 2-7 2-72-76 4-4. 2-43 2-6 2-582-64 2-422-46 2-983-1 2-902-95 2-83 2-93 3-3-1 2-62-8 2-3-2-5 2-93-0 33-1 2-62-8 1-7 1-92 1-98 2-72-8 Ins. Ins. ; sol. pot. Ins. Sol. h. imp. Insol. Insol. Sol. imp. Sol. h. Insol. Sol. h. insol. [nsol. Inf. )ecrep. in Fus. dif. r us. Fus. dif. ?us. Fus. edg. ?us. ?us, en. ?us. gls. ?us. gls. Fus. gls. 2 Opal Amor. tfncl. VIncl. Tricl. Tricl. Mass. Tricl. Mncl. Tricl. Tricl. Cl.? rh.? Mncl. ? Comp. Tet. Tet. Mass. Mass. Amor. Tet. Hex. Hex. Tet. Tet. Rhm. Comp. Rhm. Amor. Rh. Mncl. Rh. Rhdr. p p TrcL II. FELSPAR. 3 Orthoclase 4 Ryacolite 5 Albite 6 Andesin 7 Saccharite 8 Labradorite .. 9 Couzeranite ... 10 Anorthite 11 Oligoclase 12 Petalite 13 Spodumene ... 14 Kastor [nsol. [nsol. h. Sol. w. h. Sol. h. Sol. Gel. h. Sol. w. Sol. h. Af. ac. gel. h. Sol. ef. h. Gel. h. Gel. h. Sol.h.(ig.gel.) Imp. sol. Sol. Sol. Sol. n. s. Sol. s. h. Sol. s. ; ins. h. Sol. h. SoLh. ?us. int. gls. Fus. dif. fl.yel. ?us. edg. ?us. gls. en. Fus. ef. gls. Fus. ef. gls. Fus. dif. gls. Fus. dif. edg. Fus. mag. Fus. gls. Fus. dif. gls. Fus. gls. Fus. dif. Fus. eas. gls. Fus. eas. en. Fus. int. en. Infus. int. Infus. cLfl. Int. cl.fl. Fus. dif. Fus. eas. Infus. Infus. ; fm. Blkns. Int. fus. edg. 15 Pollux 16 Amorph.felspar III. SCAPOLITE. 17 Scapolite 18 Nuttalite 19 Barsowite 20 Ottrelite 21 Palagonite 22 Dipyr . 23 Nepheline 24 Davyne ,.. 25 Gehlenite 26 Humboldtilite .. 27 Prehnite. 28 Zeuxite, &c. ... 29 Nephrite IV. HALOID STONES. 30 Lazulite 31 Calaite 32 Wavellite 33 Wagnerite 34 Amblygonite . 35 Alunite ... . 36 Aluminite 37 Pissophane 38 Latrobite ARRANGEMENT OF MINERALS. xiii NAME. Crystal- lization. Hard- ness. Specific Gravity. Acids. Blowpipe. V. LEUCITE. 39 Leucite . ITess. 5-56 2-42-5 Sol. h. Infus. 40 Porcelain spar Rh. 5-5 2-67 2-68 iSoL h. Fus. eas. 41 Sodalite .. Tess. 5-5 2-282-29 Gel. Fus. eas. 42 Hauyne Tess. Tess. 55-5 5-5 2-42-5 2-252-27 Sol. h. Sol.h. Deer. fus. Fus. 43 Nosean 44 Ittnerite Tess. Tess. Rhdr. 5.5 5-5 55-5 2-372-4 2-382-42 2-842-95 Gel. h. Gel. h. GeLh. Fus. e Fus. eas. Fus. ens, \ "** J 1 * f / 45 Lapis Lazuli ... 46 Eudialite VI. ZEOLITES. XN^/ ' ^T] 47 Analcime Tess. 5-5 2-12-25 Gel. h. Fus. 48 Natrolite Rh. 55-5 2-172-26 Gel. h. Fus. 49 Scolezite Mncl. 55-5 2-22-3 GeLh. Fus. twists. 50 Damourite Mass. 1-5 2-72-8 Sol. s. insol. h. Fus. dif. 51 Thomsonite ... Rh. 55-5 2-32-4 Gel. h. Fus. dif. int. 52 Stilbite Rh. 3-54 2-12-2 Sol. h. Fus. dif. int. ! 53 Aedelforsite ... Mass. 6 2-6 Gel. Fus. int. 54 Heulandite .. Mncl. 3-54 2-12-2 Sol. dep. sil. Exf. ; int. ; fus. 55 Brewsterite ... Mncl. 55-5 2-122-2 Sol. dep. sil. Fus. int. 56 Epistilbite ^57 Apophyllite ... 58 Okenite Rh. Tet. Rh. 3-54 4-55 5 22-2 2-3-2-4 2-282-36 Sol. h. Sol. exf. h. Sol. gel. h. Fus. en. Fus. en. ; exf. Fus. en. frths. 59 Pectolite .... Mncl. ? 5 2-69274 SoLh. ;ig.gel. Fus. eas. 60 Chabasite Rhdr. 44-5 22-2 Sol. or gel. h. Fus. en. 61 Faujasite 62 Harmotome ... Tet. Rh. 4-5 1-92 2-32-4 Sol. h. Sol. h. dif. Fus. fait. Fus. dif. 63 Phillipsite 64 Zeagonitej-ZVcMW/i Rh. Tet. 4-5 66-5 2-152-19 2:18 GeLh. Gel. h. Fus. eas. !nfus. Zeagonite,.ffaMS. 65 Laumonite p Mncl. 4-5 33-5 2-22-3 Gel. h. Gel. h. Fus. eas. Fus. eas. 66 Leonhardite ... Mncl. 33-5 2-25 Sol. Fus. eas. ; exf. 67 Glottalite Tess. 34 2-18 Fus. int. en. 68 Edingtonite ... Tet. 44-5 . 2-7-2-75 Gel. h. Fus. dif. VII. MICA. 69 Potash-Mica ... Mncl. 2-3 2-83-1 Insol. Fus. 70 Lithia-Mica ... Mncl. ? 23 2-83-1 Sol. impr. Fus. eas. 71 Magnesia -Mica 72 Lepidomelane 73 Chloritoid Hex. Hex. Mass. 2-53 3 5-56 2-852-9 3-0 3-55 Sol. s. Sol. h. n. Insol. Fus. dif. Fus. blk. mag. Inf. mag. 74 Chlorite Hex. 11-5 2-782-96 Sol. s. Fus. dif. edg. 75 Ripidolite Rhdr. 23 2-612-77 Sol. s. Exf. ; fus. edg. 76 Talk Rh. mncl. j. 2-682-75 Insol. Inf. exf. 77 Schillerspar ... 78 Antigorite Mncl. p 3-54 2-5 2-62-8 Sol. s. ; imp. h. 2-62 ISol. h. dif. Fus. mag. Fus. dif. en. 79 Hydropite Mass. 34 2-65 I Infus. 80 Serpentine 81 Picrosmine ... Rh. 33-5 2-53 2-52-6 2-52-7 Sol. s. h. Fus. dif. Inf. (H. = 6.) 82 Villarsite Rh. 3 2-93 iSol. dif. Infus. XIV TABULAR VIEW OF THE NAME. Crystal- lization. Hard- ness. Specific gravity. Acids. Blowpipe. 83 Spadaite Amorph. 2-5 Sol. eas. h. Fus. 84 Gymnite Mass. 2-216 Sol. con. h. sil. Fus. 85 Chonikrite ... Mass. 2-53 2-91 Sol. h. Fus. boils. 86 Pyrosklerite Rh. ? 3 2-72-8 Sol. h. Fus. dif. 87 Kammererite Hex. 1-52 2-76 .. Inf. exf. 88 Pyrosmalite... Hex. 44-5 33-2 Sol. n." Fus. 89 Cronstedtite... Rhdr. 2-5 3-33-5 GeLh. Int. fus. edg. 90 Stilpnomelan Mass. 34 33-4 Sol. imp. Fus. dif. 91 Brucite Hex. 2 2-3 2-4 Sol. eas. Tnfus. 92 Hydromagnesite Amorph. 1-52 ? Sol. eff. Infus. 93 Nemalite Fibrous 2 2-4 Sol. slow. ef. Inf. 94 Seybertite ... Hex.? 4-56 33-16 Sol. con. ac. Inf. 95 Margarite Monocl. 3-54-5 3'03 Sol. Int. fus. dif. 96 Pyrophyllite Rh. ? 1 2-72-8 Sol. imp. s. Inf. exf. 97 Anauxite Mass. 23 2-26 Fus. edg. 98 Pholerite Mass. 0-51 2-32-6 Ins. h. Infus. 99 Rosellan Mass. 2-5 2-72 Fus. dif. VIII. HORN- BLENDE, 'MOO Hornblende... Monocl. 5_6 |2-9 3-4 Ins. sol imp. Fus. int. 101 Augite Monocl. 5 6 3-2 3-5 Sol. imp. Fus. ^02 Hypersthene Monocl. 6 3-33-4 Insol. Fus. eas. 103 Bronzite Monocl. 4-55 3-23-5 Insol. Fus. dif. 104 Diallage Mass. 4 3-23-3 Insol. Fus. eas. 105 Rhodonite ... Monocl. ? 55-5 3-53-6 Insol. Fus. 106 Tephroite Tet. 5-5 4-04-2 Gel. h. Fus. eas. 107 Troostite Rhdr. 5-5 4-04-1 Sol. n. Fus. edg. 108 Wollastonite Monocl. 5 2-72-9 Gel. h. Fus. dif. 110 Achmite Monocl. 66-5 3-53-6 Sol. imp. Fus. eas. Ill Sordawalite... Mass. 44-5 2-52-6 Sol. imp. Fus. 112 Krokydolite... Mass. 4 3-23-3 Insol. Fus. eas. 113 Pyrallolite ... Tricl 3-54 2-52-6 Insol. (?) Fus. dif. edg. 114 Pyrargillite ... Rh. ? 3-5 2-5 Sol. h. Infus. 115 Karpholite ... Fibrous 55-5 2-93 Sol. imp. !! Fus. int. 116 Babingtonite Tricl. 55-5 3-43-5 Sol. w. h. Fus. eas. ef. 117 Isopyre Amorph. 5-56 2-93 Sol. impf. Fus. mag. 118 Polylite Mass. 66-5 3-23 [nfus. 1J9 Tachylite ... Amorph. 6-5 2-52 Sol. h. Fus. eas. IX. CLAYS. 120 Kaolin ,., Mass. 1 12-2 Sol.w.s. ;insol.h [nfus. 121 Clay Comp. 1-8 27 Fus. 122 Rock soap ... Comp. 2 " '. ..... 123 Plinthite Comp. -3 2-34 Inf. bkns. 124 Green-earth... Mass. 2 2-8 Insol. Fus. 125 Yellow-earth Comp. 2 2-2 Sol. imp. h. Inf. 126 Halloysite .... Amorph. 52-5 1-92-1 Sol. con. s. [nfus. 127 Fuller's Earth Amorph. 1-5 1-82 Sol. con. s. 128 Allophane ... Mass. 3 1-82 Gel. Inf. int. 129 Schrotterite... Amorph. 33-5 1-92 Gel. h. 'Inf. whtns. ARRANGEMENT OF MINERALS. XV NAME. 1 Crystal- lization. Hard- ness. Specific gravity. Acids. Blowpipe. 130 Challilite 131 Bole Comp. Comp. Comp. Comp. Comp. Comp. Mass. Mass. Mass. Comp. Com p. Mass. Comp. Mass. Tess. Tess. Tess. Tet. Monocl. Tricl. Monocl. Tricl. ? Monocl. ? Rh. Rh. Rh. Hex. Tess. Rh.? Tet. Tet. Tess. Tess. Rhdr. Rhm. Rhm. Mass. Tricl. ? Monocl. Hex. Rhdr. Rhm. Rhdr. Rh. Monocl. 4'5 12 2'53 12 2-53 2 23 23 1-5 1-5 2-2-5 2-5 2-5 3-5 6-57-5 7-5 66-5 6-5 6_7 6-57 57 77-5 67 77-5 77-5 2-53 6 5-5 7-5 6 8 8 9 8-5 8 7-5 3-54 7-5 7-5-8 7-58 77-5 6-57-5 6-57 6-5 2-25 2-22-5 2-5 23 2-42-6 2-13 2-32-4 2-82-9 2-26 2-6 0-81 2-232-3 2-13 2-5 3-54-3 3-73-8 3-13-3 3-33-5 3-23-5 33-3 3-53-7 3-23-3 2-98 3-13-3 3-53-8 3-33-4 2-32-4 3-75 3-10 44-7 3-9 3-43-8 4-14-3 3-94 3-683-8 3-43-6 3-43-6 2-97 33-1 2-62-8 2-93 2-52-7 33-3 3-33-5 3-13-25 Sol. '" Gel. imp. Sol. imp. h. Sol. w.T Sol. s. Sol. h."" Sol. impf. h. Insol. Sol. h. Sol. imp. h. [gn. sol. Ign. sol. tnsol. [nsol. fnsol. fns. h.; imp. s. [nsol. Sol. w. ac. Sol. pul. Sol. imp. [nsol. Sol. pul. s. fnsol. fnsol. [nsol. Insol. Insol. Insol. Insol'.'" Insol. Insol. Sol. imp. Sol. imp. s. Gel. s. Sol. Inf. whtns. Fus. Infus. Infus. 132 Teratolite 133 Kollyrite 1 34 Lithomarge . . , 135 Miloschin 136 Kerolite 137 Agalmatolite 138 Soapstone ... 139 Pipestone 140 Meerschaum 141 Pimelite 142 Dermatin 143 Retinalite X. GARNET. 144 Garnet Infus. Infus. Fua. edg. Fus. Infus. Fus. edg. Fus. edg. Bkns. Inf. wtns. Fus. eas. Fus. dif. Fus. intum. Fus.eas.intum. Fus. Fus.eas.intum. Infus. [nfus. [nfus. [nfus. [nfus. Decrep. infus. Exf. infus. Infus. Fus. eas. Infus. [nfus. 'nfus. infus. infus. nfus. infus. Infus. Fus. Fus. intum. Fus. dif. edg. Infus. Fus. slow Fus. ; or int. Infus. Fus. dif. edg. 145 Pyrope 146 Helvine ... 147 Idocrase 148 Epidote 149 Axinite 150 Cyanite 151 Sillimanite ... 152 Bamlite 153 Andalusite ... 154 Staurolite 155 Diaspore 156 Hydrargillite 157 Periclase 158 Glaucophane XL GEMS. 159 Zircon 160 Malacon 161 Spinel 162 Autoraalite ... 163 Corundum ... 164 Chrysoberyl... 165 Topaz 166 Pycnite ... 167 Leucophane. . 168 Euclase 169 Emerald 170 Phenakite ... 171 lolite 172 Tourmaline... 173 Chrysolite ... 174 Chondrodite... xvi TABULAR VIEW OF THE NAME. Crystal- lization. Hard- ness. Specific gravity. Acids. Blowpipe. XII. METALLIC STONES. 175 Lievrite Rh. 5-56 3-94-2 Gel. h. Fus. eas. 176 Hisingerite ... Mass. 3-54 2-63 Sol. ; sil. Fus. dif. 177 Anthosiderite Mass. 6-5 3 Sol. h. Fus. dif. mag. 178 Nontronite ... Mass. 1 2-08 Gel. w. acids. Dcr. mag.; inf. 179 Pinguite Mass. 1 2-32-4 Sol. h. ; sil* Fus. edg. 180 Chloropal Mass. 2-53 2-12-2 Sol. h. imp. Infus. 181 Chlorophaeite Mass. Soft. 2-02 Fus. 182 Thorite Mass. 4-64-8 Gel. h. Infus. 183 Eulytine Tess. 4-55 5-96 Gel. h. Fus. eas. 184 Gadolinite ... Mncl. 6-5 44-4 Gel. h. Incan. int. 185 Allanite Rhm. 6 3-23-7 Gel. h. Fus. frths. 186 Tschewkinite Mass. 55-5 4-53 Gel. w. h. Int. fus. ]87 Cerite Hex. 5-5 4-95 Sol. h. gel. s. Inf. yel. 188 Pyrochlore ... Tess. 5 3-84-3 Sol. con. s. Fus. dif. 189 Oerstedtite ... Tet. 5-5 3-63 Infus. 190 Keilhauite ... Mass. 67 3-69 Sol. h. pul. Fus. eas. 191 Wohlerite ... ? 56 3-41 Sol. w. con. h. Fus. 192 Polymignite... Rhm. 6-5 4-806 SoL con. h. Inf. 193 Polykrase Rhm. 56 55-15 Sol.s. ;h. imp. Inf. dcr. 194 Perowskite ... Tess. 5-5 4 Af. imp. Infus. 195 Aeschynite ... Rhm. 55-5 4-95-1 Sol.con.s.imp. Inf. int. 196 Mengite Rhm. 55-5 5-48 Sol. w. con. s. Inf. mag. 197 Monazite Mncl. 55-5 55-25 Sol. h. Inf. 198 Samarskite ... Rhm. 5-5 5-625 Sol. h. Fus. II. ORDER. SALINE STONES. I. FAM. CALO SPAR. 199 Calc-spar Rhdr. 3 2-62-8 Sol. h. n. ef. Inf. 200 Dolomite Rhdr. 3-54-5 2-82-95 Sol. h. dif. Inf. 201 Breunnerite... Rhdr. 44-5 2-93-1 Sol. w, ac. Inf. mag. 202 Magnesite ... Comp. 35 2-83 Sol. w. ac. Infus. 203 Mesitine-spar Rhdr. 3-54 3-33-4 Sol. w. ac. Inf. 204 Arragonite ... Rhm. 3-54 2-93 Sol. h. n. ef. Inf. dcrp. II. FLUOR-SPAR. 205 Fluor- Spar .. Tess. 4 3-13-2 Sol. s. h. n. Decrp. fus. 206 Yttrocerite ... Mass. 45 3-43-5 Sol. h. Infus. 207 Fluocerite ... Hex. 45 4-7 Inf. Fl. 208 Fluocerine ... Mass. 4-5 Inf. Fl. 209 Cryolite Rhm.? 2-53 2-93 Sol. s. h. Fus. eas. 210 Chiolite Rhm. 4 2-72 Sol. s. Fus. eas. 211 Hopeite Rhm. 2-53 2-76 Sol. ac. Fus. eas. 212 Apatite Hex. 5 3-163-22 Sol. n. h. Fus. dif. 213 Herderite Rhm. 5 2-93 Sol. w. h. Fus. dif. 214 Childrenite ... Rhm. 4-55 ... . 215 Xenotime ... Tet. 4'5 4-39 Inf. 216 Boracite Tess. 7 2-93 Sol.h."" Fus.dif. ARRANGEMENT OF MINERALS. xvii NAME. Crystal lization Hard- ness. Specific gravity. Acids. Blowpipe. 2 1 7 H y droboracite 1 Mass. 2 192 Sol. h. n. Fus. eas. 218 Datolite Mncl. 55-5 2-93 Gel. h. Fus. eas. III. HEAVY SPAR. 219 Barytes ...... Rhm. 33-5 4-34-7 Ins. Dcrp. fus. dif. 220 Dreelite Rhdr. 34 3-23-4 Sol. h. imp. ef Fus. eas. 221 Witherite ... Rhm. 33-5 4-24-3 Sol. h. n. ef. Fus. eas. 222 Alstonite Rhm. 44-5 3-63-8 Sol. h. ef. Infus. 223 Baryto-calcite Mncl. 4 3-637 SoL h. ef. Inf. 224 Celestine Rhm. 3 35 3-9 4 Slight af. Dcr. fus. eas. 225 Strontianite... Rhm. 3-5 3-6-3-8 Sol. ef. Fus. dif. ; int. IV. GYPSUM. 226 Gypsum Mncl. 1-52 22 2-4 [nsol. Exfol. fus. en. 227 Anhydrite ... Rhm. 33-5 2-83 [nsol. ?us. dif. en. 228 Polvhalite ... Rhm. 3-5 2-72-8 SoL wtr. ?ua. 229 Glauberite ... Mncl. 2-5-3 2-72-85 Jem. wtr. Jeer. fus. 230 Pharmacolite |Mncl. 22-5 2-628 SoL eas. ? us. en ; ars. fin. 231 Haidingerite Rhm. 22-5 2-82-9 SoL eas. Fus. 232 Berzeliite Mass. 5-5 2-52 SoL n. Infus. V. ROCK SALT. 233 Rock Salt ... Tess. 2 2-12-2 Sol. wtr. !! Fus. 234 Alum Tess. 22-5 1-751-9 SoL wtr. !! Sul. fms. 235 Alunogene ... ? 1-52 1-61-7 SoL wtr. 1! Infus. 236 Glauber Salt Mncl. 1-52 1-41-5 SoL wtr. !! Fus. hep. 237 Melanterite... Mncl. 2 1-81-5 SoL wtr.!! Fus. evap. 238 Botryogene ... Mncl. 22-5 22-1 SoL wtr. imp. Int. 239 Copiapite Cryst. ... ... Sol. wtr. ... 240 Coquimbite ... Hex. 22-5 2 2-1 Sol. wtr. Sul. fms. 241 Tectizite Rhm. 1-52 I Sol. wtr. ! Fus. 242 Cyanose Trcl. 2-5 2-22-3 SoL wtr. ! Red. Cu. 243 Goslarite Rhm. 22-5 2 2*1 SoL wtr. !! Int. 244 Bieberite MncL ... ol. wtr. Sul. fms. 245 Johannite Mncl. 22-5 3-19" Sol. wtr. 246 Natron... MncL 1-5 41-5 ol. wtr. Ef. with sil. 247 Thermonatrite Rhm. 5 51-6 sol. wtr. Ef. with sil. 248 Trona Mncl. 2-53 2-12-2 ol. wtr. Ef . with sil. 249 Gaylussite ,.. 250 Borax Mncl. Mncl. 2-5 22-5 1 92 171-8 ol. wtr. imp, ol. wtr. Fus. eas. Intm. fus. 251 Sassoline Trcl. 1-41-5 ol. wtr. Frth. fus. 252 Nitre Rhm. 1-92 ol. wtr. Fus. ! cl. fL 253 Nitratine Rhdr. 52 2-12-2 ol. wtr. Fus. ; cl. fl. 254 Nitrocalcite... Fibr. oL wtr. Fus. eas. 255 Nitromagnesite Fibr. ol. wtr. ?us. eas. 256 Sal-ammoniac Tess. '52 1-56 ol. wtr. ! Vol. 257 Mascagnine ... Rhm. 22-5 1-71-8 ol. wtr. ! Jcr. fus. voL 258 Arcanite Rhm. 2-53 1-73 ol. wtr. Jcr. fus. cryt. 259 Thenardite ... Rhm. 2-5 2-6 2-7 ol. wtr. Fus.cLfl. 260 Epsomite Rhm. 22-5 1-7 1-8 oL wtr. ! J r us. b xviii TABULAR VIEW OF THE III. ORDER. SALINE ORES. NAME. Crystal- lization. Hard- ness Specific gravity. Acids. Blowpipe. I. FAM. SPAHRY IRON ORES. 261 Siderite 262 Ankerite 263 Diallogite Rhdr. Rhdr. Rhdr. Rhm. Tet. Hex. Rhdr. Rhm. Rhdr. Rhm. Rhm. Rhm. Mncl. Rhm. ? Rhm. Amor. Mass. Rhdr. Mass. Mncl. Mncl. Acic. Rhdr. Mass. Amor. Rhm. Rhm. Rhm. Mncl. Mncl. Amor. Rhm. Amor. Mass. Rhm. Hex. Fibr. Tess. Rhm. Mncl. Rhm. Mncl. Rhm. ? 3-54-5 3-5 4 3-54-5 3-54-5 2-53 4-5 5 5 4-5 55-5 4-55 45 3-5 4-55-5 4 23 3 5 23 3-54 3-54 2 2 1-52 4-55 22-5 9 354 2-53 5 34 4 .i 1-52 33-5 3 12 2-5 3-54 2-5 3-54 2 33-5 3-73-9 2-9 3-1 3-33-6 3-33-6 4-35' 4-14-5 3-33-5 4-14-2 3-63-8 3-94 3-53-6 2-27 3-43-5 3-43-5 2-32-5 2-03 3-23-3 2-02-3 3.73.8 3-64 2-4 26 33-1 44-1 2-83 4-24-6 3-33-5 4-24-4 4-14-3 3-33-4 3-63-8 3-5 3-84-3 44-3 3-55 353-9 2-93 3-13-2 2-93 3-73-9 2-62-7 3-33-4 Sol. ef. Sol. ef. Sol. ef. w. h. Sol. ef. Sol. ef. Sol. ef!'" Sol. ; sil. gel. Sol. Sol. h. Sol. w. s. Sol. h. eas. Sol. Sol. h. Sol. h. Sol. h. Gel. h. s. Gel. h. s. Sol. ef. Sol. ef. Sol. ef. Sol. eas. Sol. ef. Sol. " Sol. Sol. n. eas. Sol. ac. Sol. n. eas. Sol. n. eas. Sol. n. eas. Sol. eas. Sol. h. n. Sol. eas. Sol. h. eas. Sol. eas. Sol. h. n. eas. Sol. h. Inf. bkns. mag. Inf. bkns. mag. Inf. dcr. Inf. Inf. Inf. phos. Infus. Dcr. inf. Dcr. inf. Fus. intm. Dcr. fus. Fus. mag. Fus. eas. Fus. Fus. mag. Fus. ef. Fus. dif. Inf. cl. fl. Inf. cl. fl. Fus. red. Fus. red. Zn. Cu. Dcr. fus. Dcr.!! fus. Fus. intm. Fus. eas. Ar. Fus. Ar. Red. Cu. Fus. dcr. Fus. cl. fl. Fus. Fus. dcr. Fus. cl. fl. Fus. eas. Fus. eas. Fus. Ar. mag. Fus. Ar. mag. Inf. Ar. mag. Fus. Cu. Fus. mag. Fus. eas. 264 Manganocalcite 265 Lanthanite 266 Parisite 267 Calamine 268 Galmei 269 Williamite 270 Triplite 271 Zwieselite 272 Triphyline 273 Hureaulite 274 Heterozite 275 Alluaudite 276 Pitticite 277 Diadochite II. COFFER- SALTS. 278 Dioptase 279 Chrysocolla 280 Azurite 281 Malachite 282 Aurichalcite ... 283 Chalcophyllite... 284 Tirolite 285 Erinite 286 Liroconite 287 Olivenite 288 Euchroite 289 Klinoclase 290 Phosphorochalcite 291 Thrombolite ... 292 Libethenite 293 Tagilite 294 Ehlite 295 Atacamite 296 Volborthite 297 Arseniosiderite 298 Pharmakosiderite... 299 Scorodite 300 Symplesite 301 Brochantite... . 302 Vivianite 303 Dufrenite..., ARRANGEMENT OF MINERALS. XIX NAME. Crystal- lization Hard- ness. Specific gravity. Acids. Blowpipe. 304 Uranite [Tet. Tet. Mncl. Trcl. ? Rhm. Rhm. Mncl. Mncl. Rhm. Mncl. Tet. Rhm. Rhm. Hex. Hex. Amor. Hex. Tet. Tet. Mass. Mncl. Rhm. Mncl, Mass. Tess. Tet. Fol. 12 22-5 2-5 22-5 335 3 2-5 22-5 2-53 2-53 2-53 2-53 3-54 3-54 4 3 3 3 44-5 2-53 5 3-5 2-53 44-5 11-5 12 11-5 33-2 3-53-6 2-93 33-1 6-46-6 6-26-3 66-4 6-87 6-4 5-35-5 66.2 77-1 5-23 6-97 7-27-3 6-9 4-7 6-87-2 6-36-9 7-98-1 6-36-4 5-9-6-1 575 5-55-8 6-86-9 5-55-6 6-46-5 5-5 Sol. n. Sol. n. Sol. eas. Sol. eas. Sol. n. ef. SoL dif. Sol. n. e Sol. n. ef. imp. Sol. n. SoL n. ef' Sol. n. eas. Sol. Sol. n. Sol. n. Sol. Sol. n. eas. Sol. w. n.; h.s. SoL n. Sol. n. Sol. w. h.; n. Sol. h. Sol. n. imp. Sol. h. Af. imp. SoL ncl. SoL con. n. h. Af. imp. !! [nsol. SoL h. n. imD. Fus. Fus. Fus. Ar. Co. Fus. Ar. Ni. Dcr. Pb. Dcr. fus. Pb. Intm. red. Pb. Fus. Red. Pb. Fus. red. Pb. Fus. red. Fus. cl. fl. Fus. eas. Fus. Red. Pb. Dcr. fus. red. Dcr. fus. red. Fus. [ntm. fus. imp. Dcr. fus. red. Fus. [ntm. fus. Dcr. fus. ef. Fus. red. Ag. Vol. Fus. eas. red. Fus. eas. sub. Fus. slag. Fus. dif. 305 Chalcolite 306 Erythrine 307 Nickeline III. LEAD-SALTS. 308 Cerussite 309 Anglesite 310 Leadhillite 311 Lanarkite 312 Caledonite 313 Linarite 314 Phosgenite 315 Mendipite 316 Cotunnite 317 Pyromorphite ... 318 Mimetesite 319 Bleinierite 320 Vanadinite 321 Wulfenite 322 Scheelitine ....... 323 Plombgomme .. 324 Crocoisite 325 Melanochroite... 326 Vauquelinite ... 327 Bismuthite 328 Kerate 329 Calomel 330 lodite 331 Coccinite 332 Bromite Tess. Tet Tet. 12 4-*4 : 5 5-86 5-96-2 333 Romeite 334 Scheelite ... IV. ORDER. OXIDIZED ORES. I. FAM. OXIDIZED IRON ORES. 335 Magnetite 336 Chromite 337 Franklinite 338 Haematite Tess. Tess. Tess. Rhdr. 5-56-5 5-5 66-5 5-56-5 55-5 55-5 56 66-5 67 4-95-2 4-44-5 5.5-S 5-15-3 65 3-44 384-4 4-65 4-74-9 6-37 Sol. h. Af. dif. !!! Sol. h. Sol. dif. Insol. Sol. h. eas. SoL h. Sol. dif. h. ncL Sol. dif. h. ncL InsoL Fus. dif. !!! tnf. mag. [nf. incan. Bkns. mag. Fus.dif. !!mag. Fus. dif. Inf. Inf. In (red. St.) 339 Irite Fol. Mass. Rhm. Rhdr. Tess. Tet. 340 Limonite 341 Gotheite 342 Ilnrenite 343 Iserine II. TIN ORE. 344 Cassiterite XX TABULAR VIEW OF THE NAME. Crystal- lization. Hard- ness. Specific gravity. Acids. Blowpipe. 345 Wolfram 346 Columbite 347 Tantalite Mncl. Rhm. Rhm. p Rhm. Tet Mncl. Rhm. Tet. Tet. Amor. Hex. Rhm. Rhm. Rhm. Tet. Tet. Amor. Mncl. Amor. Amor. Mass. Amor. Amor. Amor, Amor. Earthy. Mass. Mass. Mass. Mass. Mass. Tess. Rhdr. Hex. Hex. Rhm. Tess. 55-5 6 6-6-5 55-5 6-5 5-56 55-5 5-56 66-5 5-56 5-5 22-5 6-57 3-54 5-5 66-5 5-56 4-55 3-5 11-5 3 12 Soft" Soft Soft 23 3-5-4 44-5 2-53 1-53 7-17-5 5-46-4 7-1-8 5-45-8 4-6 5-85-9 3-43-6 4-14-2 4-24-3 3-84 6-48 9-39-5 4-75 4-84-9 4-34-4 4-74-8 4-84-9 4-14-2 4-85-1 3-13-2 2-12-2 2-33-7 22-7 4-34-7 3-73-8 4-6 " 8-0 5-76 5-8 5-45-5 5-5-5-6 3-63-7 Sol. w. h. Insol. Af. dif. !!! Insol. Insol. Sol. s. ; h. imp. Insol. Insol. Sol. w. con. s. Sol. w. n. ncl. Sol. h. Sol. h. Sol. w. h. Sol. h. Sol. h. Sol. s. red. Sol. ncl. green. Sol. h"."" Fus. mag. Infus. Inf. Inf. brown. Inf. Inf. Int. fus. dif. I Inf. Inf. Inf. Inf. Infus. Infus. Infus. Inf. Inf. Inf. Inf. exf. Fus. Cu. Inf. Inf. Fus. Fus, Red. Not red. Bkns. Inf. green. Fus. red. Pb. Fus. red. Inf. Fus. Cu. Fus. Cu. Inf. phos. Fus. eas. !! Vol. 348 Yttrotantalite.. 349 Euxenite 350 Fergusonite 351 Sphene 352 Brookite 353 Rutile 354 Anatase 354a Pechurane 355 Plattnerite III. MAN- GANESE ORES. 356 Pyrolusite 357 Polianite 358 Manganite 359 Hausmannite ... 360 Braunite 361 Psilomelane 362 Crednerite 363 Cupreous manganese 364 Earthy cobalt ... 365 Wad Ochres. 366 Cobalt Ochre ... 367 Molybdena 0.... 368 Bismuth 369 Antimony O. ... 370 Tungsten 371 Uranium 372 Minium Sol. h. Sol. h. Sol. am. Sol. eas. Sol. n. Sol. potash. Sol. h. n. Sol. h. n. 373 Lead Ochre 374 Chrome 375 Tellurite IV. RED COPPER ORES. 376 Cuprite 377 Chalcotrichite ... 378 Tcnorite 379 Zincite Sol. ac. Sol. h. eas. Sol. wtr. dif. V. WHITE ANTI- MONY ORES. 380 Valentinite 381 Arsenite .. ARRANGEMENT OF MINERALS. xxi III. ORDER. NATIVE METALS. ONLY ONE FAMILY. NAME. Crystal- lization. Hard- ness. Specific gravity. Acids. Blowpipe. 382 Platina Tess. Tess. Hex. Tess. Tess. Tess. Rhm. Tess. Tess. Rhdr. Rhdr. Rhdr. Hex. Tess. 45 4-55 7 67 2-53 2-53 3-5 fluid 33-5 33-5 3-5 3-5 22-5 1-5 17 19 Sol. ncl. Sol. n. Insol. Insol. Sol. ncl. SoL n. eas. Sol. n. Sol. con. n. sol. n. eas. Sol. ncl. ef. Sol. n. ncl.!J Sol. .n. Sol. n. Fus. dif. !!! Inf. Inf. Inf. Fus. dif. Fus. eas. Fus. fins. Vol. Vol. Hg. Ag. Fus. fms. Fins. Fus. eas. Fus. eas. Fus. eas. 383 Palladium 384 Osmiumiridium 385 Tridium ... 11-812-2 19-321-2 2223 1719*4 101M 9-49-8 13-513-6 13-714 6-66-8 6-16-2 5*7 5*8 386 Gold 387 Silver . .. 388 Antimony-silver 389 Mercury 390 Amalgam 391 Antimony 392 Arsenic-Antimony 393 Arsenic 394 Tellurium 395 Lead . 6-16-3 11-3 11-4 9.69-8 8-58-9 77-8 396 Tin(?) 397 Bismuth . Tess. Tess. Tess. 2-5 2-53 4-5 Sol. n. Sol. n. Sol. h. Fus. eas. Fus. eas. Inf. 398 Copper . 399 Iron... VI. ORDER SULPHURETTED METALS. I. FAM. PYRITES. 400 Pyrite Tess. 66-5 4-9 5-1 Sol n Fms. fus 401 Marcasite 402 Pyrrhotine 403 Leucopyrite 404 Mispickel Rhm. Hex. Rhm. Rhm 66-5 3-54-5 55-5 5-5 6 4-64-9 4.447 7-17-4 6 6-2 Sol. n. Sol. h. Sol. n. Fms. fus. Fus. mag. Fus. mag. 405 Cobaltine Tess. 5'5 6 6-1 Sol w. n. Fus 406 Smaltine Tess. 5-5 1 6-4 7-3 Sol n Fus eas 407 Modumite 408 Linneite Tess. Tess. 6 5-5 6-76-9 4-9 5 Sol. n. Fus. eas. sub. 409 Griinauite 410 Gersdorffite 411 Ullmannite 412 Breithauptite ... 413 Plakodine 414 Nickeline 415 Rammelsbergite Chloanthite 416 Millerite Tess. Tess. Tess. Hex. Rhm. Hex. Tess. Rhm. Rhdr. 4-5 5-5 55-5 5 55-5 5-5 5-5 5-5 3-5 5-15-2 66-6 6-26-5 7-57-6 7-98-1 7-57-7 6-46-6 77-2 5-2 5-3 Sol. n. Sol. n. imp. SoL con. n. Sol. ncl. eas. Sol. n. Sol. con. n. Sol. con. n. Sol. con. n. Sol. ncl. Fus. mag. Fus. fms. ! Fus. fms. !! Fms. fus. dif. Fus. eas. fms. Fus. fms. !! Fus. eas. Fus. eas. Fus eas. 417 Eiserinickelkies 418 Chalcopyrite ... 419 Bornite... Tess. Tet. Tess 3-54 3-54 3 4-6 4-14-3 4*9 5-1 Sol. ncl. Fus. mag. Fus. eas. Fus. eas. 420 Domeykite Mass. 33-5 Insol. h. Fus. eas. XX11 TABULAR VIEW OF THH NAME. Crystal- lization. Hard- ness. Specific Gravity. Acids. Blowpipe. 421 Arseniate of) manganese \ Mass. ... 5-55 Sol. nel. Fms. burns. II. LEAD GLANCE. 422 Galena Tess. 2-5 7-47-6 Sol. n. )cr. fus. red. 423 Cuproplumbite... Tess. 2-5 6-46-5 ?us. eas. 424 Clausthalite ... Tess. 2-53 8-2-8-8 Sol. n. ^ms. Se. vol. 425 Selencopperlead Mass. 2-5 77-5 Sol. n. Fms. fus. 426 Onofrite Mass. 2.5 7-3 Insol. n. Vol. 427 Naumannite Mass. 2-5 8 Sol. con. n. eas. fus. 428 Argentite Tess. 22-5 77-4 Sol. con. n. S. Fus. int. red* 429 Stromeyerite Rhm. 2-53 6-26-3 Sol. n. S. Fus. eas. 430 Redruthite ... Rhm. 2-53 5-55-8 Sol. w. n. S. Fus. sput. 431 Kupferindig . . Hex. 1-52 3-83-9 Sol. n. Burns, fus. 432 Eukairite 3ryst. Soft. ... Sol. n. Fus. fms. 433 Berzeline. Cryst. Soft. Fus. Se. 434 Nagyagite ... Tet. 11-5 6-87-2 Sol. n. Au. Fus. fms. Au. 435 Altaite Tess. 3 3-5 8-18-2 Sol. n. eas. Fus. vol. 436 Hessite Mass. 2-53 8-38-9 Sol. w. n. Fms. Ag. 437 Tetradymite Rhdr. 12 7-48-5 SoL n. Fus. eas. 438 Molybdenite Hex. 11-5 4-64-9 Sol. w. s. ncl. Inf. brns. III. GREY AN- TIMONY ORES. 439 Stibine Rhm. 2 4-64-7 Sol. w. h. ; n. Fus. eas. 440 Jamesonite ... Rhm. 22-5 5-55-7 Sol. w. h. Dcr. fus. vol. 441 Zinckenite ... Hex. 13-3-5 5-35-35 Sol. w. h. Dcr. ! ! fus. vol. 442 Plagionite ... Mncl. '2-5 5-4 Sol. w. h. 3cr. ! ! fus. red. 443 Boulangerite Mass. 3 5-86 Sol. n. imp. Fus. eas. fms. 444 Geokronite ... R,hm. 23 6-46-5 Sol. h. Fus. eas. vol. 445 Steinmannite Tess. 2-5 6-86-9 Dcr. ! fus. eas. 446 Plumosite ... Acic, 1-3 5-75-9 Sol. w. h. Fus. eas. ! 447 Dufrenoysite Tess. ... 5-55 Sol. w. n. Fus. eas. 448 Wolfsbergite Rhm. 3-5 4-75 Dcr. fus. fms. 449 Kermes Mncl. ? 11-5 4-54-6 Sol. h. 450 Berthierite ... Mass. 23 44-3 Sol. h. ncl. Fus. fms. 451 Bisinuthine ... Rhm. 22-5 6-46-6 Sol. n. Fus. sput. 452 Aciculite Rhm. 2-5 6-76-8 Sol. n. Fus. eas. fms. 453 Kobellite Mass. Soft. 6-3 Sol. con. h. Fus. red. 454 Sylvanite Rhm. 1-52 88-3 Sol. ncl. Fus. red. Au. IV. GREY COP- PER ORE. 455 Fahlore Tess. 34 4-35-2 Sol. n. Fus. tnag. 456 Tennantite ... Tess. 4 4-34-5 Sol. n. green. Dcr. fus. mag. 457 Bournonite .. Rhm. 2-53 5-75-9 Sol. n. blue. Dcr, fus. 458 Wolchite Rhm. 3 5-75-8 Fus. ef. 459 Freieslebenite Rhm. 22-5 66-4 Fms. red. Ar. 460 Stephanite ... Rhm. 22-5 6-26-3 Sol. w. n.' Fus. red. Ar. 461 Polybasite ... Hex. 22-5 66-25 SoLn. Dcr. fus. eas. 462 Sternbergite... Rhm. 11-5 4-24-3 Sol. ncL Fus. mag. Ar. ARRANGEMENT OF MINERALS. xxui NAME. Crystal- lization. Hard- ness. Specific gravity. Acids. Blowpipe. 463 Stannine Tess 4 4 -34 -5 Sol. n blue. Fus. dif. 464 Cupreous Bis- j muth ) 465 Bismuthic Silver V. BLENDES. 466 Blende 467 Woltzine Rhm. Acic. Tess. Mass. 3-5 Soft. 3-54 4-5 5 3-94-2 3-66 Sol. n. S. Sol. n. Sol. con. n. Sol h Fus. eas. frth. Fus. eas. Dcr.!fus.dif.!! Dcr fus dif ' 468 Alabandine 469 Hauerite Tess. Tess 3-54 4 3-94 3'46 Sol. h. Sol h Fus. dif. !! 470 Greenockite VI. RUBY BLENDES. 471 Pyrargyrite 472 Miargyrite 473 Xanthokon 474 Cinnabar 475 Realgar 476 Oroiment... Hex. Rhdr. Mncl. Rhdr. Rhdr. Mncl. Rhm. 33-5 22-5 22-5 22-5 22-5 1-52 I -5 2 4-84-9 5-55-8 5-35-4 55-2 88-2 3-43-6 3-4 3-5 Sol. h. Sol. n. Sol. n. Sol. n. Sol. ncl. A dif. Snl. Tir.1. Dcr. Fus. eas. fms. Fus. red. Ar. Fus. ftus- Ar. Subl. Fus. brns. Suhl. brns VII. ORDER. THE INFLAMMABLES. I. FAM. SULPHUR.' 477 Sulphur i Rhm. 1-5 2'5 I'd 2-1 478 Selen-sulphur ... II. DIAMOND. 479 Diamond III. COALS. 480 Graphite Tess. Hex. 10 0-5 1 3-5-3-6 1-9 22 481 Anthracite 482 Common Coal... 483 Brown Coal 484 Peat IV. MINERAL RESINS. 485 Bitumen 486 Elaterite Amor. Comp. Comp. Amor. Fluid. Comp. 22-5 22-5 S >ft." 1-41-7 1-21-5 0-51-5 0-70-9 0-8 1-23 487 Asphaltum 488 Piauzite Comp. Coinp 2 1'5 1-11-2 T22 489 Ixolyte 490 Amber Amor. Amor. 1 2 2'5 1-008 1 1-1 491 Retinite 492 Walchowite 493 Copalme 494 Berengelite 495 Guyaquillite 496 Hartine ......... Amor. Amor. Amor. Amor. Amor. Amor. 1-52 1-52 1-5 11-15 1-031-07 1-046 1-092 1-115 XXIV TABULAR VIEW OF THE ARRANGEMENT OF MINERALS. NAME. Crystal- lization. Hard- ness. Specific Gravity. Acids. Blowpipe. 497 Middletonite ... 498 Ozokerite Amor. Amor. ... 1-6 0-940-97 499 Hatchetine 500 Fichtelite Amor. Cryst. 0-6 501 Hartite ... Mass. 1 1-046 502 Konlite Mass. 0-88 503 Scheererite 504 Idrialite Mncl. Mass 1 1-5 11-2 1-41-6 V. INFLAMMABLE SALTS. 505 Mellite Tet 2 2-5 1-4 1-8 Sol n White Al 506 Oxalate Acic. 2 2-12-3 Sol. eas. Red ash. MANUAL OF MINEKALOGY. INTRODUCTION. THE proper object of Natural History is the investigation and sys- tematic description of the numerous individual objects that compose the material world, so far as these can be known from observation or experiment. For this purpose it endeavours to classify or combine the immense variety of natural productions into groups of more or less extent, and distinguished by certain definite characteristics. The first great natural division that appears in this process of classifica- tion is into organic and inorganic bodies. The former are distinguish- ed by possessing organs, that is, instruments for the performance of certain functions, and consequently a compound frame, the various parts of which are not uniform, but different in structure, in chemical composition, and mode of aggregation. The inorganic products of nature, on the contrary, present no distinction of parts, no organs with definite functions ; but each individual, so far as it is mechani- cally separable, consists of parts uniform in composition and state of aggregation. The former class also exhibit a union of solid and fluid substances, are endowed with internal powers of motion, are fitted to pass through a particular series of changes, are destined to endure only for definite periods, and preserve the species by a succession of similar individuals. The latter are either homogeneous in every part, or mere aggregates of bodies that are so ; they have no internal prin- ciple of motion, no definite period of existence, no regular series of changes, and no peculiar arrangement for continuing the species, when the individual perishes. In external form these two departments of nature also widely differ ] organic bodies being bounded by curred lines and rounded surfaces, the inorganic generally by straight lines 2 DIVISIONS OF NATURAL HISTORY. and planes ; often, however, very irregularly disposed. Organic beings, too, usually consist of more complex and apparently less definite che- mical compounds, than the inorganic, but these intimately united and rendered distinctly one by the principle of life. Hence each individual exists more isolated and independent, and has its form and magnitude more precisely determined by the primary idea of the species than ap- pears to be the case in the inorganic world. Each of these departments of nature must be again divided. The organic world forms the two great divisions of the vegetable and animal kingdoms, the subjects of the sciences of Botany and Zoology. The divisions of inorganic bodies are less definite and precise, and the sciences treating of them are more often confounded. Natural history can take notice of them only as individual objects, resigning the de- scription of them as mere substances to chemistry, and the account of many of their other properties and phenomena to general physics. In this respect the science of inorganic nature only follows the same course with botany and zoology. Like these it borrows from che- mistry and physics such facts as are necessaiy to characterize the ob- jects of its consideration, or to elucidate their true nature as indivi- duals ; but it at the same time claims for itself an independent domain, and cannot justly, any more than zoology or botany, be merged into a mere section of chemical science. The confusion of these two sciences must prove injurious to both, leading chemistry away from its true object on the one hand, and, on the other, causing the neglect of many important branches of the natural history of the inorganic world. The latter has now grown up into several independent, though closely-con- nected sciences. Of these Mineralogy is properly the science of simple minerals, that is, of those natural products which possess a certain definite form and composition. Geognosy again considers these mi- nerals, as, united in large masses, they form those rocks of which the crust of the globe is built up, and gives an account of their relative po- sition, age, and probable mode of origin. The ocean and atmosphere would be included in this division of natural history, were not their phenomena so varied and important, as to require that they should be rather regarded as independent departments of natural history. A still wider field is opened for Geology, which, viewing the earth as a whole, and searching out the laws that regulate the succession of phenomena on its surface, endeavours from the consideration of the present to unravel the history of the past, to form some probable con- jectures in reference to that of the future. Properly speaking, there- fore, geology is not a mere branch of the natural history of the inor- ganic or mineral kingdom ; but is the highest result of the study of nature as a whole,. the systematic combination of the most general NATURE OF MINERALOGY. laws to which the mineral, the vegetable, and animal kingdoms are or have been subject, and a combined view of the various revolutions which, in obedience to these, or still higher laws, the material system of nature may have undergone. Mineralogy being thus limited to the natural history of simple mi- nerals, it becomes necessary to define what is to be understood by this term. In the strictest sense, a mineral species is a natural inorganic body, possessing a definite chemical composition, and assuming a re- gular determinate form or series of forms. This definition will exclude many bodies often included in the mineral kingdom. Thus, all the artificial salts of the chemists, all the inorganic secretions of plants and animals, all the remains of former living beings now imbedded in rocks, are excluded from the consideration of the mineralogist. Some substances, originally organic products, have indeed by common con- sent found a place in mineral systems, as coal, amber, and mineral resins ; but this is a departure from the strictness of the definition, and in most cases had perhaps better have been avoided. So also some amorphous substances, with no precise form or chemical composition, as some kinds of clay, have been introduced into works on mineralogy, but we believe often improperly, and with no beneficial result. Ag- gregates of simple minerals or rocks are likewise excluded from this science, though the various associations of minerals, their modes of occurrence, and their geological position, are important points in the history of the different species. There are, however, certain limita- tions with which the above definition must be understood, which will be subsequently pointed out. One most important object of a treatise on mineralogy should be to give such descriptions of minerals, their essential properties and dis- tinctive characters, as will enable the student to distinguish the vari- ous species, and to recognise them when they occur in nature. But to accomplish this he must first become acquainted with the Terminology or nomenclature of the science, that is, with the meaning of the terms used in describing these properties, and the various modifications they may undergo. With this is necessarily conjoined an account of these properties themselves, and of the more general laws by which their various changes are regulated. A second and closely-related portion of mineralogy is the System or Classification, giving an account of the order in which the species are arranged, and the reasons for which it has been adopted. The third and most important part of mineralogy, to which these two are properly preparatory, is the Physiography of the various species, giving an account of their characteristic marks, and a description of their appearance, or external aspect and forms ; their principal physical and chemical properties ; their mode of occur- TERMINOLOGY. FORM OF MINERALS. reuce, with their geological and geographical distribution ; and their various uses, whether in nature or in the arts. Each of these depart- ments will be considered in the following Manual in the order just mentioned, and with such fulness as their relative importance and the limits of the work will permit. PART I. TERMINOLOGY. CHAP. I. FORM OF MINERALS. BY the physical properties of a mineral as opposed to the chemical is to be understood, all those properties belonging to it as a body ex- isting in space, and consisting of matter aggregated in a peculiar way. To this division of the subject, therefore, belongs the consideration of its form as shown in crystallization ; its structure as determining its mode of cleavage and fracture ; its hardness and tenacity ; its weight or specific gravity ; and its various optical, electrical, magnetic, and other similar properties. Crystalline and Amorphous. Mineral substances occur in two dis- tinct modes of aggregation. Some consist of parts evidently arranged according to a definite law, whilst in the formation of others no such law appears to have been in operation. Their minute particles are simply collected together, and exhibit no regularity of structure or constancy of external form, and are, therefore, named amorphous. All fluid minerals are of course in this condition, together with some solid bodies, which appear to have condensed either from a gelatinous con- dition like opal, when they are named porodine, or from a state of igneous fluidity like obsidian and glass, when they are named hyaline. It may be doubted, however, how far any mineral body is truly amor- phous, as the optical properties of many that are apparently so seem to depend on some peculiar and determinate structure, though too minute to be distinguished. The other class of bodies are named cry stalline, when the regularity of structure appears only in the internal disposition of the parts ; and crystallized, when it also produces a de- terminate external form, or a crystal A familiar example of crystal- line structure is seen in a piece of loaf sugar, the 'broken surface of which presents innumerable minute polished planes, from which the light is reflected. Faces, edges, angles, axes of Crystals. The word crystal in mine ralogy designates a solid body exhibiting an original (not artificial) more or less regular polyhedric form. It is thus bounded by plane SYSTEMS OF CRYSTALLIZATION. 5 surfaces, named faces, which intersect in straight lines or edges, and these again meet in points and form angles, which, when bounded by three or more faces, are named solid angles. The space occupied by a crystal, and bounded by its faces, is often named zform of crystalliza- tion, which is thus merely the mathematical figure regarded as inde- pendent of the matter that fills it. Some crystals are bounded by equal and similar faces, and are named simple forms; whilst those in which the faces are not equal and similar are named compound forms, or combinations, being regarded as produced by the union or combina- tion of the faces of two or more simple forms. The cube or hexahe- dron (fig. 1), bounded by six equal and similar squares ; the octahe- dron (fig. 2), by eight equilateral triangles ; and the rhombohedron, by six rhombs, are thus simple forms. The axis of a crystal is a line passing through its centre and terminating either in the middle of two faces, or of two edges, or in two angles ; and axes terminating in si- milar parts of a crystal are named similar axes. In describing a cry- stal one of its axes is supposed to be vertical or upright, and is then named the principal axis. A few other technical terms used in de- scribing crystals, or the modifications they undergo, will be better explained as they occur. Those terms which are found in every ele- mentary treatise on geometry, as line, angle, circle, need not be de- fined here, as we may suppose that our readers possess so much of the rudiments of that science as is required for this purpose. The higher branches of crystallography, indeed, require considerable acquaintance with mathematics and practical skill in calculation ; but to understand the following treatise, a very moderate knowledge of the elementary principles of geometry will suffice.* Systems of Crystallization. The forms of crystals that occur in nature seem almost innumerable ; and unless some general laws by which they are regulated had been discovered, the attempt to name and describe them might have been deemed hopeless. On examining them, however, more attentively, it is soon discovered that the vari- ous faces, even in the more complex crystals, are disposed in a sym- metrical manner. When the axes of the crystals are properly chosen, and placed in a right position, the various faces are observed to group themselves in a regular and beautiful manner around these axes, and to be all so related to them as to compose a connected series produced * The beginner will find much advantage in procuring models of the forms of simple cry- stals described in the following pages, or still better by preparing them for himself from some soft material, as clay, chalk, or wood. Very instructive models may also be made of pasteboard, the faces of the crystals being cut out of the proper form and glued together ; or they may be made of glass, and one inclostd in another, so as to represent the connection of the different forms, and the manner in which they are derived from each other. Such models give far clearer notions of solid bodies than engravings on a flat surface, in which their three dimensions can bo but imperfectly represented. 6 TESSERAL SYSTEM. according to definite laws. It appears that in every mineral species there is a certain form of crystal, with axes intersecting at fixed angles, and bearing to each other definite proportions, from which, as a pri- mary, every other form of crystal observed in that mineral species may be deduced, simply by varying the proportions of these axes. It is found that in each species the axes intersect each other at angles which are constant, and that the angles formed by the intersection of the faces are also related to each other according to certain definite laws. When viewed in this manner, and referred to their simplest forms, it is seen that the innumerable variety of crystals occurring in nature may all be reduced to six distinct groups, or, as they are named, systems of crystallization.* To these various names have been as- signed by different authors, but the following are those of most im- portance, placed in parallel columns. Systems of crystallization according to Naumann. 1. Tesseral System. 2. Tetragonal System. 3. Hexagonal System. 4. Rhombic System. 5. Monoclinohedric System. 6. Triclinohedric System. Mohs. Tessular. Pyramidal. Rhombohedral. Orthotype. Hemiorthotype. Anorthotype. Weiss and G. Rose. Regular. 2 and 1 axial. 3 and 1 axial. 1 and 1 axial. 2 and 1 membered. 1 and 1 membered. Some authors conjoin the last three systems in one ; the rhombic of Breithaupt, the trimetric of Hausmann ; but as they must again dis- tinguish them in detail, it is better to divide them at first. In the fol- lowing treatise the terminology of Naumann is adopted, his method of classifying and describing crystals appearing the simplest, and best adapted to promote the progress of the student. The first, or Tesseral System, is characterised by three equal axes intersecting each other at right angles. Its forms thus present a greater degree of regularity and equality than any of the other systems, and hence Weiss has named it the regular, and Hausmann the isome- tric system, whilst the name here used is taken from tessera, a cube, which is one of its most frequent varieties. Properly speaking, this system has no chief axis, as any one of them may be so named, and placed upright in drawing and describing the crystals. Of these there are thirteen varieties, which are thus classed and named from the number of their faces : 1. One Tetrahedron, or form with four faces. 2. One Hexahedron, with six faces. ' 3. One Octahedron, with eight faces. * There is a seventh system possible, and actually met with in one variety of an artificial *alt, but as it does not occur in any mineral, we need not delay to consider it further. Nau- mann, in conformity to his method, names it the diclinohedric. HOLOHEDRIC AND HEMIHEDRIC. 7 4. Four Dodecahedrons, with twelve faces. 5. Five Icositetrahedrons, with twenty-four faces. 6. One Tetracontaoctahedron, with forty-eight faces. The dodecahedrons are again distinguished according to the form of their faces into rhombic, trigonal, deltoid, and pentagonal dodecahe- drons. One variety of icositetrahedron is named a tetrakishexahedron (i. e. four times six faces), being bounded by twenty-four isosceles triangles, arranged in six groups of four each. Another variety, also bounded by isosceles triangles, but arranged in three groups of eight, is named the triakisoctahedron (i. e. 3 x 8 faces). A third variety is the hexakistetrahedron (6x4 faces), bounded by scalene triangles, in four groups of six each. The fourth is the diakisdodecahedron (2 x 12 faces), bounded by equilateral trapeziums ; whilst the fifth and most common variety, bounded by deltoid faces, not arranged into groups, retains the original name. Some of the crystals with forty- eight faces have these arranged in eight groups of six, and for such forms the term hexakisoctahedron (6x8 faces) seems preferable. Many mineralogists have named these forms from some particular mineral species in which they occur (thus the rhombic dodecahedron is the granatoid of Haidinger, the granatohedron of Weiss) ; but the above names are both more expressive and more easily remembered. Before giving a particular description of these forms, we must remark that ciystals are characterised not only by the number, but in a still higher degree by the relative position of their faces. When attentively compared in this respect, it will be observed that the faces of the te- trahedron exactly correspond in relative position to the alternate faces of the octahedron, so that if these latter faces were supposed to increase symmetrically so as to obliterate the others, the octahedron would be changed into a tetrahedron, or form with one-half the number of faces. This is also true of many other forms, the alternate faces of which increasing symmetrically obliterate the others, and thus produce new forms with only half the number of faces. Hence the distinction of crystals into holohedric or plenotesseral forms, in which the whole or full number of faces are developed ; and hemihedric or semitesseral forms, in which only half the number of faces appear. The latter are again distinguished into two classes, the one with faces parallel to each other, two and two ; the second with faces not parallel or inclined to each other. These must not be regarded as mere arbitrary distinctions of small importance, for they express laws which nature seems to ob- serve in the formation of mineral bodies. In combinations of various forms, those with inclined and those with parallel faces are never found in union. It is even affirmed with much probability that no mineral species ever crystallizes in two of these classes of forms, and that the TESSERAL SYSTEM. apparent exceptions arise from certain forms, as the cube and octahe- dron, being both holohedric and hemihedric. A similar distinction of hemihedric and holohedric obtains in the other systems of crystalliza- tion, and in these also the several classes are no less strictly disjoined. The following is a description, with figures, of the different forms above-mentioned, beginning with The Holohedric forms. 1. The hexahedron or cube (fig. 1) is bounded by six equal squares, has twelve edges, formed by faces meeting at 90, and eight trigonal angles. The principal axes join the centre points of any two opposite faces. Examples are fluor spar, lead-glance, boracite. Fig. 1. Fig. 2. 2. The octahedron, (fig. 2), bounded by eight equilateral triangles, has twelve equal edges, with planes meeting at 109 28', and six tetragonal angles. The principal axes join the opposite angles, two and two. Ex. alum, spinel, magnetic iron ore. 3. The rhombic-dodecahedron (fig. 3) is bounded by twelve equal Fig. 9. Fig. 4. and similar rhombs, (diagonals as 1 and */2), has twenty-four equal HOLOIIEDRIC FORMS. edges of 120, and six tetragonal and eight trigonal angles. The principal axes join two opposite tetragonal angles. Ex. garnet, red copper ore, boracite. : *, 4. The tetrakishexahedrons (fig. 4) are bounded by twenty-four isosceles triangles. They have twelve longer edges which correspond to those of the primitive or inscribed cube, and twenty-four shorter edges placed over each of its faces. The angles are eight hexagonal and six tetragonal, the latter joined two and two, by the three principal axes. This form varies in general aspect, approaching on the one hand to the cube, on the other to the rhombic- dodecahedron, accord- ing as the vertical angles of the bounding triangles become more or less obtuse, or, in other words, approach or recede from the face of the inscribed cube. Ex. fluor spar, gold. 5. The triakisoctahedrons (fig. 5} are bounded by twenty-four is- osceles triangles, and like the previous form vary in general aspect from the octahedron on one side, to the rhombic-dodecahedron on the other. The edges are twelve longer, corresponding with those of the inscribed octahedron, and twenty-four shorter, three and three over each of the faces. The angles are eight trigonal and six ditetragonal, (formed by eight faces) ; the latter angles joined two and two by the principal axes. Ex. galena, diamond. Fig. 5. Fig. 6. 6. The icositetrahedrons (fig. 6) are bounded by twenty-four del- toids or figures with four sides, of which two and two adjacent ones are equal. This form varies in the limits from the octahedron to the cube, sometimes approaching the former, sometimes the latter in ge- neral aspect. The edges are twenty-four longer, and twenty-four shorter. The angles are six tetragonal joined by the principal axes, eight trigonal, and twelve rhombic, or tetragonal with unequal angles. 7. The hexakisoctahedrons (fig. 7), bounded by forty-eight scalene triangles, vaiy much in general aspect, approaching more or less to all 10 TESSERAL SYSTEM. the preceding forms; but most frequently they have the faces arranged either in six groups of eight, or eight of six, or twelve of four faces. There are twenty-four long edges, often corresponding to those of the Fig. 7. rhombic-dodecahedron ; twenty-four intermediate edges lying in pairs over each edge of the inscribed octahedron ; and twenty-four short edges in pairs over the edges of the inscribed cube. There are six ditetragonal angles join- ed by the principal axes, eight hexa- gonal and twelve rhombic angles. Ex. fluor spar, garnet, diamond. The seven forms of crystals now de- scribed are related to each other in the most intimate and interesting manner. Even on a cursory view it is evident that they all have a general similarity, so that one as it were passes into or separates from the others almost by insensible gradations. This will appear more distinctly from the following account of the derivation of the forms, with which is conjoined an explanation of the crystallographic signs or symbols by which they are designated in the system of JSTaumann. We have adopted these symbols through- out the work, in the belief that they not only mark the forms in a greatly- abbreviated manner, enabling us to dispense with many long and cumbrous words, but also exhibit the relations of the forms and combinations in a way which words could hardly accomplish, and thus impart much valuable information which could not otherwise be obtained. By the derivation of forms is understood that process by which, from one form chosen for the purpose, and considered as the type, the funda- mental or primary form, all the other forms of that system may be pro- duced, according to certain fixed principles or general laws. In order to understand this process or method of derivation, the student should keep in mind that the position in space of any plane is fixed when the positions of any three points in it, not all in one straight line, are known. To determine the position, therefore, of the face of a crystal, it is only necessary to know the distance of three points in it from the centre of the crystal, or the points in which the face or its supposed extension would intersect the three axes of the crystal. The portion of the axes between the face of the crystal and the centre are named the parame- ters of the face, and the position of the latter is considered as suffi- ciently known when the relative length or proportion of these para- meters is known, though it may not be expressed in lines, inches, or DERIVATION OF FORMS. 11 other measure. It should also be remembered that when the position of one face is thus fixed or described, all the other faces are in like manner fixed, since they are all equal and similar, and all intersect the axes in a uniform manner. The expression, therefore, which marks or describes one face of a simple form of a crystal, marks and describes the whole figure. Some authors have assumed the cube, or hexahedron, as the funda- mental or primary form of the tesseral system from which the others may be derived, but the octahedron possesses so many advantages for this purpose, that it is generally adopted, and is taken as the primary or fundamental form, and distinguished by the first letter of the name, O. Its faces cut the half axes at equal distances from the centre ; so that these senriaxes, or the parameters of the faces, have to each other the proportion 1:1:1. In order to derive the other forms from the octahedron, the following construction is employed. The numbers refer to the descriptions above. Suppose a plane so placed in each angle of the octahedron as to be vertical to the axis passing through that angle, and consequently to be parallel to the two other axes, (or to cut them at an infinite dis- tance = o>) ; then the hexahedron or cube (1) is produced, designated by the crystallographic sign ooO oo ; expressing the proportion of the parameters of its faces, or oo : o> : 1. Figure 8, a combination of the Fig. 8. Fig. 9. two forms, shows this process partly begun, whilst in figure 9 the se- condary planes of the cube have almost obliterated the primary ones of the octahedron. If a plane is supposed placed in each edge parallel to one axis, and cutting the two other axes at equal distances, the resulting figure is the rhombic-dodecahedron (3), designated by the sign oo O, the proportion of the parameters of its faces being oo : 1 : 1. The triakisoctahedron (5) arises when on each edge of the octahedron planes are placed, cutting the axis not belonging to that edge at a distance from the centre m, which is a rational number greater than 1. The proportion of its parameters is, therefore, m : 1 : 1, and its sign wO ; the most common varieties being |O, 2O, and 3O. When, on 12 RELATION OF TE8SERAL FORMS. Fig. 10. the other hand, from a similar distance m in each two semiaxes pro- longed, a plane is drawn to the other semiaxis, or to each angle, an ikositetrahedron (6) is formed ; the parameters of its faces have consequently the proportion m : 1 : m, and its sign is mOm ; the most common varieties being 2O2 and 3O3, the former very frequent in leucite, analcime, and garnet. When again planes are drawn from each angle, or the end of one semiaxis of the octahedron, parallel to a second axis, and cutting the third at a distance w, greater than 1, then the tetrakishexahedron (4) is formed, the parameter of its faces oo : 1 : n ; its sign On ; and the most common varieties in nature ooO|, oc02, and o>03. Finally, if in each semiaxis of the octahe- dron two distances, m and w, be taken, each greater than 1, and m also greater than w, and planes be drawn from each angle to these points, so that the two planes lying over each edge cut the second se- miaxis belonging to that edge, at the smaller distance w, and the third axis at the greater distance wz, then the hexakisoctahedron (7) is pro- duced, the parameters of which are as m : n : 1, its sign mOra, and the most common varieties 3O|, 4O2, and 5O|. The mutual relation of these forms to each other, and their mode of derivation, is represent- ed in the prefixed figure (fig. 10). At the vertex of the tri- angle is the octahedron as the primary or fundamental form. By a change in one axis only, the forms on the left hand side of the figure are produced, m having all dimensions between 1 and co r and the forms mO con- sequently approaching either to O as it diminishes, or to ooO as it increases. On the right hand side of the figure are the forms in which two of the axes vary uni- formly, whilst one remains unchanged, m again having all magni- tudes from 1 to oo. In the centre line are the forms in which two axes vary, but not uniformly, so that in them the parameters of the faces are all of different dimensions. The forms on the sides are, therefore, the three variable forms whose extreme limits are marked by those at the respective angles, which are fixed forms presenting only one variety. In the centre again is the hexakisoctahedron, uniting the signs and proportions of all the other forms, and hence their common representative. In it the whole number of faces be- mOm ccO ' SEMITESSERAL FORMS. 13 longing to this system are separately shown, whereas in the other forms two or more of these faces usually coincide, so that the number appears smaller. The next class of crystals are the semitesseral forms, and first those' with oblique faces, often named tetrahedral, from their relation to the tetrahedron. (1.) This form (fig. 11) is bounded by four equilateral triangles, has six equal edges with faces meeting at 70 32', and four trigonal angles. The principal axes join the middle points of each two Fig. 11. Fig. 12. opposite edges. Ex. are grey-copper ore, boracite, and helvine. (2.) The trigonal dodecahedrons (fig. 12) are bounded by twelve isosceles triangles, and vary in general form from the tetrahedron to the hexahe- dron. There are six longer edges, corresponding to those of the inscribed tetrahedron, and twelve shorter placed three and three over each of its faces ; and four hexagonal and four trigonal angles. Ex. grey-copper ore, and bismuth-blende. (3.) The deltoid-dodecahedrons (fig. 13) are bounded by twelve deltoids, and vary in general form from the te- trahedron on the one hand, to the rhombic-dodecahedron on the other. They have twelve longer edges lying in pairs over the edges of the inscribed tetrahedron ; and twelve shorter edges, three and three over Fig. 13. Fig. 14. each of its faces. The angles are six tetragonal (rhombic), four acute trigonal and four obtuse trigonal angles. The principal axes join two 14 DERIVATION OF SEMITESSERAL FORMS. and two opposite rhombic angles. Ex. grey-copper ore. (4.) The hexakistetrahedrons (fig. 14) are bounded by twenty-four scalene triangles, and approach in general form sometimes to one of the three previous forms, sometimes to the rhombic-dodecahedron, or the hexa- hedron, or the tetrakishexahedron ; but most commonly have their faces grouped in four systems of six each. The edges are twelve shorter and twelve longer, lying in groups of three over each face of the inscribed tetrahedron, and twelve intermediate in pairs over its edges. The angles are six rhombic, joined in pairs by the principal axes, and four acuter and four obtuser hexagonal angles. Ex. dia- mond. The derivation and signs of these forms are as follows. The tetra- hedron arises when four alternate faces of the octahedron are enlarged, so as to obliterate the other four, and its sign is hence . But, as either four faces may be thus enlarged or obliterated, two tetrahe- drons can be formed, similar in all respects except in position, and together making up the octahedron. These are distinguished by the signs + and , added to the above symbol, but only the latter in general expressed thus . In all hemihedric systems two forms similarly related occur, which may thus be named complementary forms. The trigonal dodecahedron is derived from the icositetrahe- dron by the expansion of the alternate trigonal groups of faces. Its sign is 2|?i the most common variety being ?2. 2 found in grey-copper ore. The deltoid-dodecahedron is in like manner the result of the increase of the alternate trigonal groups of faces of the triakisocta- hedron, and its sign is ^. Lastly, the hexakistetrahedron arises in the development of alternate hexagonal groups of faces in the hexa- kisoctahedron, and its sign is mOn . The parallel-faced semitesseral forms are two. (1). The pentagonal Fig. 15. dodecahedrons (fig. 15) are bounded by twelve symmetrical pentagons, and vary in general aspect between the hexahedron and rhombic- dodecahedron. They have six regular (and in general longer) edges, lying over the faces of the inscribed hexa- hedron, and twenty-four generally shorter (seldom longer) edges, usually lying in pairs over its edges. The angles are eight of three equal angles, and twelve of three unequal angles. The principal axes unite each two opposite regular edges. This form is derived from the tetrakishexahedron, and its sign is On , one of the most common varieties being -- found frequently COMBINATIONS. 15 in iron pyrites and cobaltine. (2,) The dyakisdodecahedron (fig. 16), Fig. 16. form. bounded by twenty -four trapezoids with two sides equal, has twelve short, twelve long, and twenty-four intermediate edges. The angles are six equiangular rhombic, united in pairs by the principal axes, eight trigonal, and twenty-four ir- regular tetragonal angles. It is derived from the hexakisoctahedron, and its sign is [~>] the brackets being used to distinguish it from the hexakistetrahe- dron,also derived from the same primary It occurs fy iron pyrites and cobaltine. There are two other formsAthe pentagonal dodecahedron (fig. 17), and the Fig. 17. Fig. 18. pentagonal icositetpahedron, (fig. 18), both bounded by irregular pentagons, butacft yet observed in nature. Combinations^ -These forms of the tesseral system (and this is true also of the five other systems of crystallization), not only occur singly, but often two or three united in the same crystal, forming what are named combinations. In this case it is evi- dent that no one of the individual forms can be completely de- veloped, because the contemporaneous existence of several on one crystal, or round one common centre, is only possible on the condi- tion that the faces of one form shall partially interfere with the faces of another. A combination, therefore, implies that the faces of one form shall appear symmetrically disposed between the faces of the other forms, and consequently in the room of certain of their edges and angles. These edges and angles are thus as it were cut off, and new ones formed in their place, which properly belong neither to the one form nor the other, but are edges or angles of combination. Usually, TjTjxn? ueA- ^j^^M^A^rJj / <- O4 16 PLENOTESSEKAL COMBINATIONS. one form predominates more than the others, or has more influence on the general aspect of the crystal, and hence is distinguished as the predominant form, the others being named subordinate. Here again the universality of the general law will be remarked, that only forms of the same system and of the same division of it can combine together. The following terms used on this subject require explanation. A com- bination is developed when all the forms contributing to its formation are pointed out ; and its sign consists of the signs of these forms, writ^ ten in the order of their influence on the combination with a point be- tween. An angle or edge is said to be replaced, when it is cut off by one or more secondary planes ; it is truncated when cut by one plane, forming equal angles with the adjacent faces ; and an edge is be- veled when replaced by two planes, which are equally inclined to the adjacent faces. It will be readily seen that such combinations may be exceedingly numerous, or rather infinite ; and only a few of the most common can be noticed, simply as specimens of the class. Many others more complicated will occur in the descriptive part of this treatise. Among plenotesseral combinations, the cube, octahedron, and also the rhom- bic dodecahedron, are the predominant forms. In fig. 19 the cube Fig. 19. Fig. 20. has its angles replaced by the faces of the octahedron, and the sign of this combination is o>O oo. O. In fig. 20 this process may be re- Fig. 21. Fig. 22. COMBINATIONS OF SEM1TESSERAL FORMS. 17 garded as having proceeded still further, so that the faces of the oc- tahedron now predominate, and the sign, of the same two elements but in reverse order, is O. ooOoo . In fig. 21, the cube has its edges replaced by the faces of the rhombic-dodecahedron, the sign being oo O oo . oo O ; whilst in fig. 22 there is the same combination, but with the faces of the cube subordinate, and hence the symbol is oo O . ooOoo . The former figure, it will be seen, has more the general aspect of the cube, the latter of the dodecahedron. In combinations of seniitesseral forms with oblique faces, the tetra- hedron, the rhombic-dodecahedron, or even the hexahedron, seldomer a trigonal-dodecahedron, are the more common predominant forms. In fig. 23, two tetrahedrons in opposite positions, . & are corn- ig. 2 Fig. 24. bined. In fig. 24 a very complex combination of seven forms is re- presented in a crystal of grey copper ore, its full sign being 2 V c0=o(/). w0(o) . O ( P). _?0?(r). !.(*). 0300. the letters in brackets connecting them with the respective faces of the figure. As examples of combinations of semitesseral forms with parallel faces, we may take fig. 25, in which each of the angles of the Fig. 2G. cube is unsymmetrically replaced by three faces of the dyakis- dodeca- hedron, and hence ccQoo . [^] ; or fig. 26, in which the pentagonal B 18 TETRAGONAL SYSTEM. dodecahedron has its trigonal angles replaced by the faces of the octa- hedron, consequently with the sign ^^-. O. Figure 27 represents the Fig. 27. same combination, but with greater pre- dominance of the faces of the octahedron, the crystal being bounded by eight equi- lateral and twelve isosceles triangles. As formerly stated, the holohedral forms in these combinations are regarded by some authors as essentially hemihedral. Tetragonal System. This system agrees' with the former in having three axes placed at right angles ; but differs in that two of them are equal and one unequal. The last is considered the principal axis, having most influence on the symmetry of the forms, and when it is brought into a vertical position the crystal is said to be placed upright. Its ends are named poles, and the edges connected with them polar edges. The two other axes are named subordinate or lateral axes, and a plane passing through them is named the basis of the crystal. The two planes that pass through the principal and one of the lateral axes are named normal chief sections, and a plane through the chief axis intermediate to them a diagonal chief section. The name tetra- gonal is derived from the form of the basis, which is usually quadratic. There are eight tetragonal forms, of which five are closed, that is, bounded on all sides by planes, and of definite extent ; and three open, which in certain directions are not bounded, and consequently of indefinite extent. The latter, as will subsequently appear, are only the limit-forms into which some of the former pass when the axes are infinitely extended. Fig. 28. Fig. 29. The description of the varieties is as follows, it being premised that DESCRIPTION OF TETRAGONAL FORMS. 19 a crystallographic pyramid is equivalent to two geometrical pyramids joined base to base. (1.) Tetragonal pyramids (figs. 28, 29) areenclosed by eight isosceles triangles, with four middle edges all in one plane, and eight polar edges. There are three kinds of this form arising in the different position of the lateral axes. In the first these axes unite the opposite angles ; in the second they intersect the middle edges equally ; and in the third they lie in an intermediate position, or divide these edges unequally ; the latter being heniihedral forms. These pyramids are also distinguished as obtuse (fig. 28) or acute (fig. 29), according as the vertical angle is greater or less than in the octa- hedron, which, though thus intermediate between these, is never con- sidered a tetragonal form. (2.) Ditetragonal pyramids (fig. 30) nre Fig. 30. . 31. bounded by sixteen scalene triangles, whose base lines are all in one plane. Their polar edges are named normal when they lie in the nor- mal chief section, or diagonal when in an intermediate position. This form rarely occurs except in combinations. (3.) The tetragonal sphe- noids (fig. 31) are bounded by four isosceles triangles, and are the hemihedral forms of the first variety of tetragonal pyramids, from which they arise in the same manner as the tetrahedron from the oc- tahedron. (4.) The tetragonal scalenohedron (fig. 32), bounded by eight scalene triangles, whose bases rise and fall in a zig-zag line, is the hemihedral form of the ditetragonal pyramid. The latter two forms are rare; and the fifth tetragonal form, the trapezohedron only, if ever, observed in scapolite, needs no further notice. The tetra- gonal prisms (fig. 33) are bounded by four planes parallel to the principal axis ; the ditetragonal by eight similar planes. In them the principal axis is supposed to be prolonged infinitely or to be un- 20 DERIVATION OF TETRAGONAL FORMS. bounded. Where it is very short and the lateral axes infinite, the basal pinacoid is formed, consisting merely of two parallel faces. Fig. 32. Fig. 33. Both it and the prisms are open, and consequently must be bounded by some other forms. The various series of tetragonal crystals found in the different spe- cies of the mineral kingdom are distinguished from each other only by their relative dimensions. To determine these, one of the series must be chosen as the fundamental form, and for this purpose a tetragonal pyramid of the first variety, designated by P as its sign, is selected. The angle of one of its edges, especially the middle edge, found by measurement, determines its angular dimensions ; whilst the propor- tion of the principal axis (a) to the lateral axes supposed equal to 1, gives its linear dimensions. The parameters, therefore, of each face of the fundamental form are 1:1: a. Now if m be any Crational) number, either less or greater than one, and if from any distance ma in the principal axis planes be drawn to the middle edge of P, then new tetragonal pyramids of the first kind, but more or less acute or obtuse than P, are formed. The general sign of these pyramids is mP, and the most common varieties 4P, 2P, 3P ; with the chief axis equal to 4, twice or thrice that of P. If m becomes infinite, or = o>, then the pyramid passes into a prism, indefinitely extended along the principal axis r and with the sign ooP ; if m = 0, which is the case when the lateral axes are supposed in- finite, then it becomes a pinacoid, consisting properly of two basal faces, open towards the lateral axes and designated by the sign OP. The ditetragonal pyramids are produced by taking in each lateral axis distances n greater than 1 , and drawing two planes to these points from each of the intermediate polar edges. The parameters of these planes are, therefore, m : I : n, and the general sign of the form wPn, COMBINATIONS. the most common values of n being i, 2, 3, and oo. When n = oo, a tetragonal pyramid of the second kind arises, designated generally by mPoo, the most common in the mineral kingdom being Poo and 2 Poo . The relation of these to pyramids of the first kind is shown; in fig. 34, where ABBBX is the first, and AC OCX the second kind of pyramid. In like manner from the prism coP, the ditetragonal prisms P2. 4P2. |P3. M c P d o u b r z x f e a The Hexagonal System. The essential character of this system is, that it has four axes, three equal lateral axes intersecting each other in one plane at 60, and one principal axis at right angles to them. The extremities of the principal axis are named poles, and sections through it and one lateral axis, normal chief sections. The plane through the lateral axes is the basis, and from its hexagonal form gives the name to the system. As in the last system its forms are either closed or open ; and are divided into holohedral, hemihedral, and tetartohedral, the last forms with only a fourth part of their faces developed. The tetartohedral and many of the hemihedral forms are of rare occurrence, and only a few of the more common re- quire to be here described. The hexagonal pyramids (figs. 40, 41) are bounded by twelve isosceles triangles, and are of three kinds, according as the lateral axes fall in the angles, in the middle of the lateral edges, or in another point of these edges, the latter being hemihedral forms. They are also classed as acute or obtuse, but without any very precise limits. The trigonal pyramid, shown by G. Rose to occur in quartz, is bounded by six triangles, and may be viewed as the hemihedral form of the hexagonal. The dihexagonal pyramid is bounded by twenty-four scalene triangles, but has never been observed alone, and rarely even in combinations. These forms when the principal axis becomes infinite pass into prisms, the first producing the hexagonal prism of six sides, the latter the DERIVATION OF FORMS. 23 dihexagonal of twelve sides ; or form similar pinacoids when their chief axis equal to 0, or the lateral axes infinitely extended. Fig. 40. Fig. 41. As the fundamental form of this system, a particular pyramid P is chosen, and its dimensions determined either from the proportion of the lateral to the principal axis (1 : a), or from the measurement of its angles. From this form, (rf), others are derived exactly as in the tetragonal system. Thus dihexagonal pyramids are produced with the general sign, mPn, the chief peculiarity being that, whereas in the tetragonal system n might have any rational value from 1 to GO, in the hexagonal system it can only vary from 1 to 2, in conse- quence of the geometric character of the figure. When n = 2 the di- hexagonal changes into an hexagonal pyramid of the second kind, whose sign is niP2. When m is = oo various prisms arise from similar changes in the value of n. Few hexagonal mineral-species form perfect holohedric combina- tions. Though quartz and apatite usually appear as such, yet pro- perly the former is a tetartohedral, the latter a hemihedral species. In holohedric species the predominant faces are usually those of the two hexagonal prisms, ooP, and ooP2, or of thepiuacoid, OP; whilst the pyramids P and 2P2 are the most common subordinate faces. Figure 42 represents the prism, bounded on the extremities by two pyramids ; one, P forming the point, the other 2P2 the rhombic faces on the angles, or ooP. P. 2P2. Sometimes the prism and first py- ramid are combined with the pinacoid, the latter cutting off the point of the crystal. At other times the lateral edges of the prism are replaced by the second prism o>P2, producing an equiangular twelve- sided prism, which always represents the combination ooP. ooP2, and cannot occur as a simple form. An example of a more complicated combination is seen in this fig. 43, of a crystal of apatite, whose sign with 24 RHOMBOHEDRAL FORMS. tbe corresponding letters is, ooP (Af). ooP2 (e). OP (P). 4P (?} P OP). 2P (). P2 (a). 2P2 (*). 4P2 (rf). Fig. 42. Fig. 43. Hexagonal minerals more frequently crystallize in those series of hemihedral forms that are named rhombohedral, from the pre- Fig. 44. in them of rhombohedrons. These are (fig. 44) bounded by six rhombs, whose lateral edges do not lie in one plane but rise and fall in a zig-zag manner. The principal axis unites the two trigonal angles, formed by three equal plane angles, and in the most common variety the secondary axes join the middle points of two opposite sides. When the polar edges form an angie of more than 90 the rhom- bohedrons are named obtuse, when of less acute. Hexagonal scalenohedrons (fig. 45) are bounded by twelve scalene triangles, whose lateral edges do not lie in one plane. The principal axis joins the two hexagonal angles, and the secondary axes the middle points of two opposite lateral edges. It is a very remarkable peculiarity of the scaleno- hedron, that its lateral edges always correspond with those of a certain rhombohedron that may be KHOMBOHBDRIC COMBINATIONS. 25 inscribed in it, and from which it may therefore be regarded as de- rived, a view illustrated by fig. 46. The rhombohedron is derived from the first kind of hexagonal pyramid by the hemihedric development of its al- ternate faces. Its general sign should therefore be ~, but on several grounds it is found better to designate it by R or wR, and its complementary figure by mR. When the prism or pinakoid arise as its limiting forms, they are designated by R and OR, though in no respect changed from the limiting forms ooP and OP of the py- ramid. The scalenohedron is properly the hemihedric form of the dihexago- nal pyramid, but is better derived from the inscribed rhombohedron mR. If the halves of the principal axis of this are multiplied by a definite number w, and then planes drawn from the extre- mities of this enlarged axis to the late- ral edges of the rhombohedron, as in fig. 46, the scalenohedron is constructed. Hence it is designated by wzR n , the n being written on the right hand like an algebraic exponent : and the dihexagonal prism is in like manner designated by ooR n . The combinations of rhombohedric forms are very numerous, some Fig. 47. Fig. 48. c' hundreds being described in calc-spar alone. Among the more com- c RHOMBIC SYSTEM. mon is the prism in combination with a rhombohedron, as in the twin crystal of calc-spar (fig. 47,), with the signooR. R, the lower half being the same form with the upper, but turned round 180. In figure 48, the rhombohedron mR has its polar edges replaced by another rhombohedron %mR ; and in figure 49 its lateral edges bevelled by the scalenohedron mR. A more complex combination of five forms is 49. Fig. 50. represented in the crystal of calc-spar, fig. 50, its sign with the letters on the faces being ~R 5 (y) . R s (r) . R(P) . 4R( . ocRfc). Many other forms occur which will be exemplified in the descriptive part of the work ; and we shall only allude further to the tetartohedric combina- tions of pure quartz or rock crystal, which shows this form of crystal- lization most distinctly, the pyramids of the first kind appearing as rhombohedrons, those of the second kind as trigonal pyramids, the di- hexahedral prisms as ditrigonal prisms, and the prism ooP2 as a tri- gonal prism. Most of these forms, however, occupy but a very sub- ordinate place in the combinations which consist essentially of the prism coP, and the rhombohedron R = -. Rhombic System. The Rhombic System is characterised by three axes, all unequal, but still at right angles to each other. One of these must be assumed as the chief axis, when the others are named sub- ordinate, but mineralogists differ much in their choice of an axis for this purpose. The plane passing through the secondary axes or the basis forms a rhomb, and from this the name is derived. This system comprises only a few varieties of forms that are essentially distinct, and its relations are consequently very simple. RHOMIHC FORMS. 27 The closed forms are, (1st.) The rhombic pyramids (figs. 51, 52), bounded by eight scalene triangles, whose lateral edges lie in one plane, Fig. 51. Fig. 52. and form a rhomb. They have eight polar edges, four acute and four more obtuse, and four lateral edges, and six rhombic angles, the most acute at the extremities of the longest axis. (2d.) The rhombic sphe- noids (fig. 53) are bounded by four scalene triangles with their late- Fig. 53. ral edges not in one plane ; and are a hemihedric form of the rhombic pyramid of unfrequent occurrence. The open forms again are, (3d.) Rhombic prisms bound- ed by four planes parallel to one of the axes which is indefinitely extended. They are divided into upright and horizontal prisms, ac- cording as either the principal or one of the lateral axes is supposed to become infinite. For the lat- ter form, the name doma or dome has been used ; and two kinds, the macrodome and the brachydome, have been distinguished. Rhombic pinakoids also arise when one axis becomes = 0, and the two others are indefinitely extended. In deriving these forms from a primary, a particular rhombic py- ramid P is chosen, and its dimensions determined either from the angular measurement of two of its edges, or by the linear proportion of its axes a:b:c; the half of the greater lateral axis b being usually assumed equal to 1. To the greater lateral axis the name macro- diagonal is frequently given ; to the shorter, that of brachydiagonal ; 28 DERIVATION OF RHOMBIC FORMS. and the two principal sections are in like manner named macrodia- gonal and brachy diagonal, according to the axis they intersect. The same terms are applied throughout all the derived forms, where they consequently mark only the position of the faces in respect to the axes of the fundamental crystal, without reference to the relative magnitude of the derived axes. By multiplying the principal axis by any rational number m, greater or less than 1, a series of pyramids arise, whose general sign is mP, and their limits the prism and pinakoid, the whole series being con- tained in this formula, OP mP P mP - o> P ; which is the fundamental series, the lateral axes always remaining un- changed. From each member a new series may, however, be developed in two directions by increasing one or other of the lateral axes. When the macrodiagonal is thus multiplied by any number n greater than 1, and planes drawn from the distance n to the polar edges, a new pyra- mid is produced, named a macropyramid, with the sign mPn, the mark over the P pointing out the axis enlarged. When m = oo a macrodome results, with the sign niP oo. If the shorter axis is mul- tiplied, then brachypyramids and brachydomes are produced with the Fig. 54. Fig. 55. signs mPn and mPco . So also from the prism ooP, on the one side,numerous macro- prisms ooPw, with the_ limit- ing macropinakoid ooPoo ; on the other, numerous brachy- prisrns ooPw, with the limit form ooPoo , or the brachy- pinakoid. In figs. 54, 55, the two domes are shown in their relation to the primi- tive pyramid, the signs on the faces being those used in the system of Mohs. The pyramids seldom oc- cur independent, or even as the predominant forms in a combination, sulphur, how- ever, being an exception. Prisms or pinakoids usually give the general character to the crystal, which then ap- pears either in a columnar or tabular, or even in a rectan- RHOMBIC COMBINATIONS. gular pyramidal form. The determination of the position of these cry- stals, as vertical or horizontal, depends on the choice of the chief axis of the fundamental form. In the topaz crystal, fig. 56, the brachyprism and the pyramid are the predominant elements, associated with the prism, its sign and letters being ooP2(7) . P(o) . ooP(m). Fig. 57 of Fig. 56. Fig. 57. Fig. 58. M M stilbite or desinine is another example, the macropinakoid ocPoo or M, being combined with the pyramid P (Y), the brachypinakoid o>Pco (T) and the basal pinakoid OPfP). Another instance is figure 58 of a lievrite crystal, where the brachyprism and pyramid combine with the macrodome, or ooP2 . P . Poo . The following figures arc very common forms of barytes ; figs. 59 and 60 being both composed of Fig. 59. Fig. 60. Fig. 61. the pinakoid, a brachydome and macrodome with sign OP(c) . Poo (/). ^Pco (d), the variation in aspect arising from the predominance of dif- ferent faces ; and fig. 61, consisting of the macrodome ^Poo , the prism , and the pinakoid OP. 30 MONOCLINOHEDRIC SYSTEM. The Monodinohedric System. This system is characterised by three unequal axes, two of which intersect each other at an oblique angle, and are cut by the third at right angles. One of the oblique axes is chosen as the chief axis, and the other axes are then distin- guished as the orthodiagonal (right-angled), and clinodiagonal (ob- lique-angled). The same terms are applied to the chief sections, and the name of the system refers to the fact that these two planes and the base, together with two right angles, form also an oblique angle C. The forms of this system approach very near to those of the rhom- bic series, but the inclination of the axes, even when almost a right angle, gives them a peculiar character, by which they are always readily distinguished. Each pyramid thus separates into two alto- gether independent forms or hemipyramids. Three varieties of prism also occur vertical, inclined, and horizontal with faces parallel to the chief axis, the clinodiagonal, or the orthodiagonal. The hori- zontal prisms, like the pyramids, separate into two independent par- tial forms, named hemiprisms or hemidomes. The inclined prisms are often designated clinodomes, the term prism being restricted to the vertical forms. Orthopinakoids and clinopinakoids are also distinguished from their position in relation to the axes. The monoclinohedric pyramids (fig. 62) are bounded by eight sca- -p- Q2 lene triangles of two kinds, four and ' four only being similar. Their la- teral edges lie all in one plane, and the similar triangles are placed in pairs on the clinodiagonal polar edges. The two pairs in the acute angle be- tween the orthodiagonal and basal section are designated the positive hemipyramid ; whilst the two pairs in the obtuse angles of the same sections form together the negative hemipy- ramid. But as these hemipyramids are wholly independent of each other, they arc rarely observed combined in the complete form; More frequent- ly each occurs alone, and then forms a prism-like figure, with faces parallel to the polar edges, and open at the extremities. Hence, like all prisms, they can only appear in combination with other forms. The vertical prisms are bounded by four equal faces parallel to the principal axis, and the cross section is a rhomb ; the clinodomes hdve a similar form and section ; whilst the horizontal prisms or domes have unequal faces, and their section is a rhomboid. The mode of derivation of these forms closely resembles that of the MONOCLINOIIEDRIC COMBINATIONS. 31 rhombic series. A complete pyramid is assumed as the fundamental form, and designated + P, in order to express the two portions of which it consists. Its dimensions are given when the proportion of its axes a : b : c, and the angular inclination of the oblique axes C, which is also that of the orthodiagonal section to the basis, are known. The fundamental series of forms is, OP + niP + P + mP oo P ; from each of whose members, by changing the dimensions of the other axes, new forms may be again derived. Thus from + mP, by multiplying the orthodiagonal by any number n, a series of orthopyramids + mPn, is produced with the orthodomes + mPoo , as limiting forms. The clinodiagonal produces a similar series, distinguished from the former by the sign being put in brackets, thus, + (mPn,) with the limiting clinodome (raPco) always com- pletely formed, and therefore without the signs + attached. From coP arise orthoprisms, ooPw, and the orthopinakoid, ooPoo ; and clino- prisms ( ocPw) and the clinopinakoid ( ooPoo ). The combinations of this system may be easily understood from their resemblance to those of the rhombic ; the chief difficulty being in the occurrence of partial faces, which, however, closely resemble the hemihedric forms of the previous systems. We shall therefore only select a few examples frequently observed in the mineral kingdom. Fig. 63 represents a very common form of gypsum crystals (ooPoo) (P) . co P(/) . P (/). The most common form of augite is represent- ed in fig. 64, with the sign ooP (m) . ooPoo (r) . ( ooPoo ) (J) . P (*). Fig. 63. Fig. 64. Figure 65 is a crystal of common felspar or orthoclase, composed of the clinopinakoid (ooPoo) (AT), the prism, coP (T), the basal pina- koid OP (P), and the hemidomes, 2Poo (y) : to which, in fig. 66 of the same mineral, the hemipyramid, P (0), and the clinodome (2P ) (), are added. 32 TRICLINOHEDRIC SYSTEM. Fig. 65. Fig. 66. Triclinohedric System. This is the least regular of all the systems, and departs the most widely from symmetry of form. The axes are all unequal and inclined at different angles, so that to determine any rystal or series of forms the proportion of the axes a : b : c, and also their angles, or those of the inclination of the chief sections, must be known. As in the previous system one axis is chosen as the principal axis, and the two others distinguished as the macrodiagonal and erachydiagonal axes. In consequence of the oblique position of the principal sections, this system consists entirely of partial forms wholly independent on each other, and each composed only of two parallel faces. The complete pyramid is thus broken up into four distinct quartlffpyramids ; and the prism into two hemiprisms. Each of these partial forms is thus nothing more than a pair of parallel planes, and the various forms consequently mere individual faces. This circum- stance renders many series of triclinohedric crystals very unsymme- trical in appearance. Triclinohedric pyramids (fig. 67) are bounded by eight triangles, Fig. 67. whose lateral edges lie in one plane. They are equal and parallel two and two to each other ; each pair forming, as just stated, a tetartopyramid or open form, only limited by combination with other forms, or, as we may suppose, by the chief sections. The prisms are again either vertical or in- clined ; the latter named domes, and their section is always rhomboidal. In deriving the forms, the fundamental pyramid is placed upright with its brachydiagonal axis to the spectator, and the partial forms designated, the two upper by T and P', the two lower by ,P and P /} as in the figure. The further derivation IMPERFECTIONS OF CRYSTALS. 33 now follows as in the rhombic system, with the modifications already mentioned, so that we need not delay on it longer, especially as the minerals crystallising in these forms are not numerous. Some combinations of this system, as the series exhibited by most of the felspars, approach very near to the monoclinohedric system ; whilst others, as the blue copper, or vitriol, and axinite, show great Fig. 68. incompleteness and want of symmetry. In the latter case the determi- nation of the forms is often difficult and re- quires great attention. As specimens, we may notice the albite crystal (fig. 68), in which P is the basal pinakoid OP, M the brachydiagonal pinakoid ocpco, s the upper light pyramid P', / the right hemiprism coP', T the left hemi- prism oo'P, and x the hemidome 'P'oo . Figures 69 and 70 are crys- Fig. 69. Fig. 70. tals of axinite, the former fix>m Dauphine, the latter very common in Cornwall, of whose faces the following is Naumann's development, r the macropinakoid oopoo ; P the left hemiprism oo'P ; u the left upper quarter pyramid T ; I the left upper quarter pyramid 2'P ; s the left upper partial form of the macropyramid 3'P3, and x the hemidomo 2'P, oo .* Imperfections of Crystals. In the foregoing description of the forms of crystals, the planes have always been supposed smooth and even, the faces equal and uniform, or at the same distance from the centre or point of in- tersection of the axes, and each crystal also perfect or fully formed Some authors combine the 4th, 5th, and 6th systems in one, considering the latter two as mere subdivisions of the rhombic. In some respects this view is advantageous, but in ethers tends to render the subject more complex, and therefore is not adopted here. 34 HEMIMORPHISM STRIDE . and complete on every side. In nature, however, these condi- tions are rarely, if ever, realized, and the edges of crystals are seldom straight lines, or the faces mathematical plane surfaces. A very interesting variety of these irregularities which pervades all the systems, except the tesseral, is named hemimorphism by Breithaupt and others. In this the crystals are bounded on the opposite ends of their chief axis by faces belonging to wholly distinct forms, and hence only the upper or under half of each form is produced, or the crystal, as the name implies, is half-formed. Figure 71 represents a common variety of tourmaline, bounded on the upper end by the planes of the Fig. 71. Fig. T2. rhombohedrons R and 2R, and on the lower end by the basal pina- koid. In fig. 72 of electric calamine, the upper extremity shows the basis k, two brachydomqs o and p ; and two macrodomes m and I ; whilst on the lower end it is bounded by the faces P of the primary form. This appearance becomes more interesting from the fact, that most hemimorphic crystals acquire polar electricity from heat, that is, exhibit opposite kinds of electricity at opposite ends of the crystal. The faces of crystals are very frequently rendered imperfect by strife or minute linear and parallel elevations and depressions. These are believed to arise in the oscillatory combination of two crystalline forms, alternately prevailing through small spaces. The striae, there- fore, are in reality the edges of combined forms, and can often be readily interpreted on this theory. They are very common on quartz, shorl, and some other minerals ; and frequently indicate combinations where only a simple form would otherwise appear to exist. The cubes and pentagonal dodecahedrons of iron pyrites are frequently striated, and in three directions at right angles to each other. In calcspar the faces of the rhombohedron, R (g in fig. 47 above) are almost never without stride parallel to the oblique diagonal. The IMPERFECT CRYSTALS. 35 striation is said to be simple, when only one series of parallel lines ap- pears on each face ; or feathered when two systems diverge from a common line. In other crystals the faces, then said to be drusy, are covered by numerous projecting angles of smaller crystals ; an imper- fection often seen in fluor spar. When these again become so small as to be no longer determinable, the surface is said to be rough ; but a similar imperfection is also occasioned by other inequalities. The faces of crystals occasionally appear curved either as in tourmaline and beryl from the peculiar oscillatory combination mentioned ; or by the union of several crystals at obtuse angles like stones in a vault, as in desmin and prehnite. 'A true curvature of the faces probably occurs in the saddle-shaped rhombohedrons of brown spar and iron spar (see Mohs, i. fig. 180), in the lens-like crystals of gypsum, and in the curved faces so common on diamond crystals. In chabasite similar curved faces occur, but concave. In galena and augite the crystals are often rounded on the corners as if by an incipient state of fusion. On other crystals the faces are rendered uneven from inequalities following no certain rale. These imperfections frequently furnish valuable assist- ance in developing veiy complex combinations, since it appears that all the faces of each individual form are distinguished by the same pe- culiarity of surface. Irregularities in the forms of crystals are produced when the cor- responding faces are placed at unequal distances from the centre, and consequently differ in form and size. Thus the cubes and octahedrons of iron pyrites, galena and fluor spar are often lengthened along one axis. Quartz is subject to many such irregularities which are seen in a very remarkable manner on the beautiful transparent and sharply angular crystals from Dauphine, which thus appear altogether unsymmetric. In such irregular forms the axes do not exactly agree with the defi- nition above. Instead of one line, they are then represented by an infinite number of lines, parallel to the ideal axis of the figure. The same irregularity earned to a greater extent frequently causes certain faces required for the symmetry of the form, altogether to disappear an irregularity distinct both from the hemihedrism and hemimor- phism already mentioned. Again some crystals do not fill the whole space marked out by their outline, holes and vacancies being left in the faces, occasionally to such extent that they seem little more than mere skeletons. This appearance is very common on crystals produced artificially, either from solutions, by fusion, or by sublimation, as in common salt, alum, bismuth, silver, &c. A perfect crystal can only be produced when during its formation it is completely isolated, so as to have full room to expand on every side. Hence the most perfect crystals have been originally imbedded singly in some uniform rock 36 ANGLES OP CRYSTALS. mass, and freed from this either by the natural decomposition of the stone, or by art. Such crystals present the individual mineral species in its most complete isolation and most perfect state of formation. Next to them in perfection are forms that grow singly on the surface of some mass of similar or distinct composition ; and when the point of adherence is small such crystals show the form almost perfect and complete. When, however, many crystals are aggregated together, the one interferes with the formation of the other and various irregu- larities result. An incompleteness of form, or at least a difficulty in determining it, arises from the minuteness of some crystals, or from their contracted dimensions in certain directions. Thus some appear mere tabular or lamellar planes, whilst others run out into acicular, needle- shaped, or capillary crystals, in which no complete form is perceptible. One important element, however, remains unchanged amid all these modifications of the general form of the crystal, or of the condition and aspect of its individual faces. However much crystals may vary in these respects or in linear dimensions, their angular measurement remains constant. In some monoaxial crystals, indeed, Mitscherlich has shown that increase of temperature produces an unequal expan- sion in different directions, slightly changing the relative inclina- tion of the faces, but so small as to be scarcely perceptible in common measurements, and hence producing no ambiguity. More important are the angular changes which in many species accompany slight changes in chemical composition, particularly in the relative propor- tions of certain isomorphous elements. But notwithstanding all these limitations the great truth of the permanence of the angular dimen- sions of crystals, announced by Rome' de 1'Isle, remains unaffected ; only, as Mohs well states, it must not be interpreted with a rigid im- mutability, inconsistent with the whole analogy of other parts of nature. In interpreting the forms presented to us we must always endeavour to bring them under some simple geometric law, through which alone they can be understood ; being at the same time careful not to push this endeavour too far, and to imagine a simplicity which more accurate observation would have shown did not exist. The Goniometer and Measurement of Crystals. The fact just stated of the permanence of the angular dimensions of crystals, shows the importance of some accurate method of measuring their angles, that is, the inclination of two planes to each other. Two instruments have been specially used for this purpose, the common or contact goniometer, invented by Caringeau, and the reflecting gonio- meter of Wollaston. The former is simply two brass rulers turning on a common centre, between which the crystal is so placed that its faces GONIOMETER. 37 coincide with the edges of the rulers, and the angle is then measured on a graduated arc. This instrument is sufficiently accurate for many purposes and for large crystals ; but for precise determination is far inferior to the reflecting goniometer. This requires smooth and even faces, but these may be very small, even the hundredth of an inch, in skilful hands, and as small crystals are generally most perfect, far greater accuracy can be attained, and the measurements depended on to one minute (!'). The reflecting goniometer is represented in the annexed figure. It Fi. 73. consists essentially of a graduated circle m m, divided on its edge into twice 180, or more often into half degrees, the minutes be- ing read of by the vernier hh. This circle turns on an axis con- nected with #, so that by turning this the circle is moved round, but is stopped at 180, when mov- ing in one direction, by a spring at k. The other part of the in- strument is intended to attach and adjust the crystal to be mea- sured. The first axis of mm is hollow, and a second axis, aa, passes through it from s s, so that this and all the connected parts from b to /can be turned with- out moving the circle mm. The axis d passes through a hole in fee, so that it can turn the arm de into any required position ; /is a similar axis turning the arm og; and pq a fourth axis, in like manner movable in #, and with a small knob at q, to which the cry- stal to be measured is attached. When about to use the instrument it should be placed on a table, with its base horizontal, which is readily done by the screws in it, and opposite to a window at about 12 or 15 feet distance, so that its axis shall be parallel to the horizontal bars of the window. One of the upper bars of the window, and also the lower bar, or instead of the latter a white line on the floor or table parallel to the window, should then be chosen in order to adjust the crystal. The observer 38 USE OF GOISUOMETEK. places himself behind the instrument with the side a at his right hand. The crystal is then attached to q by a piece of wax with the two faces to be measured upwards. The axis/o is made parallel to aa, and the eye being brought near to the first face of the crystal, the axes aa and p are turned till the image of the window is seen re- flected in the face with the horizontal and vertical bars in their pro- per position. The axis d is then turned through a considerable angle (say 60), and the image of the window again sought and brought in- to its proper place by turning the axis/, without moving p. When this is done that face is brought into its true position, normal to c?, so that no motion of d can disarrange it. Hence the image of the window may now be sought in the second face and brought into its true position, with the horizontal bars seen horizontal, by moving the axes d and a. When this is done the crystal is properly adjusted, and the angle is thus measured. First bring the zero of the circle and vernier to coincide, and then turn the inner axis a or ss and move the eye till the image of the upper bar of the window reflected from the more distant face of the crystal coincides with the lower bar or horizontal line seen directly. Keeping the eye in its place, turn the outer axis tt till the reflected image of the upper bar in the other face in like manner coincides with the lower line, and the angle of the two faces is then read oif on the divided circle. As the angle measured is not directly that of the faces, but of the rays of light reflected from them, or the difference of the angle wanted from 180, the circle has the degrees numbered in the reverse direction, so as to give the angle without the trouble of subtracting the one from the other. The above apparatus for adjusting the crystal is an improvement suggested by Naumann. In the original instrument the axis/o was made to push in or out in a sheath, and had a small brass plate, bent at right angles, inserted in a cleft at o, to which the crystal was at- tached. The crystal was adjusted as formerly by moving the plate, or the axis/o, and by slight motion of the arm de, which should be at right angles nearly to be when used. A considerable improve- ment is to have a small mirror fixed on the stand below the crystal, with its face parallel to the axis aa, and inclined at 45 to the win- dow, when the lower line can be dispensed with, and the instrument used for various other purposes of angular measurement. Many alterations have been suggested for the purpose of insuring greater accuracy, but the simple instrument is sufficient for all purposes of determinative mineralogy, and the error from the instrument will, in most cases, be less than the actual variations in the dimensions of the crystals. Greater simplicity is indeed rather desirable, and the student will often find it sufficient to attach the crystal by a piece of TWIN CRYSTALS. 39, wax to the axis a directly, and give it the further adjustment by the hand. The only use of the parts from b to q is to enable the observer to place the ciystal properly ; that is, with the edge to be measured parallel to the axis of the instrument, and as nearly as possible coin- ciding with its centre. This is effected when the reflection of the horizontal bar in the two faces appears parallel to that edge. Macles or Twin Crystals. When two similar crystals, or individuals of a mineral species, are united together with their similar faces and axes parallel, the one forms merely a continuation or enlargement of the other, and both may be re- garded as constituting only one individual. Frequently, however, two crystals are united according to very precise laws, though all their similar faces and axes are not thus parallel. Compound crystals of the latter kind are named macles or twin crystals ; and are divided into those in which the axes of the two crystals are parallel, and those in which they are inclined. The former only occur among hemihedric forms and com- binations, and the two forms are then combined in the exact position in which they would be derived from or reproduce the primary holohedric form. The second class, with oblique axes, occur both in holohedric and hemihedric forms. According to Weiss they are all regulated by the general law, that the two individuals are placed in perfect symme- try to each other, in reference to a particular face of the crystal which forms the plane of union or the equator of the made. The same law results when we suppose the two crystals originally parallel and the one turned round the normal of the united faces by 180, whilst the other is stationary. Or we may suppose a crystal cut into halves in a particular direction, and one half turned 180 on the other, and hence the name of hemitrope given to them by Hauy. The position of the two individuals in this case is the same with that of an object and its image in a mirror, whose surface then represents the plane of union. The manner in which the crystals unite also differs. Some are merely opposed or in simple contact by two faces ; others are as it were grown together and mutually interpenetrated, and are occa- sionally so completely incorporated as to appear like one single in- dividual. The twin-edges and angles in which the two unite are often re-entering ; or they may coincide in one plane, when the line of union is either imperceptible or is only marked by the meeting of two systems of striae, or other diversity in the physical characters of the two faces. The formation of twin crystals may be again repeated, forming groups of three, four, or more. When the faces of union are parallel to each other, the crystals form rows of indeterminate extent ; where they are not parallel they may return into each other in circles or 40 TESSERAL MACLES. form bouquet-like or other groups. Where crystals are merely in jux- taposition they are sometimes much shortened in the direction of the twin axis ; and where many occur in a series with parallel position, are often compressed into very thin plates, frequently not thicker than pa- per, giving to the surface of the aggregate a peculiar striated aspect. Only a few twin crystals in the different systems can be noticed, chiefly as examples of this mode of formation, and not as a complete enumeration. In the tesseral system only the tetrahedral and dode- cahedral hemihedric forms unite with parallel axes, and then produce intersecting macles like the pentagonal dodecahedrons of iron pyrites in fig. 74, and the tetrahedrons of grey copper or fahl-ore in fig. 75, a Fig. 74. Fig. 75. similar formation also occurring in the diamond. In macles with in- clined axes the two forms almost always unite by a face of the octahe- dron, and the two individuals are then generally apposed and shortened in the direction of the twin axis by one-half, so that they appear like a crystal that has been divided by a plane parallel to one of its faces, and the two halves turned round on each other by an angle of 180. In this manner two octahedrons of the spinel, magnetic iron ore r Fig. 76. Fig. 77. or automolite, (fig. 76), are frequently united. 4 The same law pre- TETRAGONAL MACLES. vailiDg the intersecting cubes of fluor spar, iron pyrites, and galena, Fig. 78 represented in fig. 77. In fig. 78 of zinc blende two rhombic dodecahedrons are united by a face of the octahedron. In the tetragonal system, twin crystals with parallel axes rarely occur, because few of the species belonging to it present he- mihedric forms. It is, however, seen in copper pyrites, and one or two other mi- nerals. Where the axes are inclined the plane of union is very often one of the faces of the pyramid Poo , or one of those faces that would regularly replace the polar edges of the fundamental form P. The crystals of tin ore obey this law, as seen in fig. 79, where the individuals are pyramidal, and Fig. 79. Fig. 80. ^** r in the knee-shaped crystal (fig. 80), where they are more prisma- Fig. 81. tic. Rutile also occurs like the latter figure ; and in both species three, four, or more crystals are frequently united. Hausmanite appears like fig. 81, in which the fundamental pyramid P prevails, on whose polar edges other crystals are often very symmetrically repeated, a central individual appear- ing like the support of all the others. Almost identical forms occur in cop- per pyrites. In the hexagonal system twin crys- t als with parallel axes are common, as in calc-spar, chabasite, specular iron, and other rhombohedric minerals. In calc-spar they often form very regular crystals,* the two individuals uniting by a plane parallel to the base, so as to appear like a single crystal, as in fig. 82, where D 42 RHOMBOHEDRIC MACLEg, each end shows the forms R. - R, but in a complementary posi- tion ; or in fig. 83 of two scalenohedrons R 3 from Derbyshire. The rhombohedric crystals of chabasite often appear intersecting each other, like those of fluor spar in fig. 77 above. The purer varieties of quartz or rock crystal in consequence of the tetartohedric character of its crystallization often exhibit twins. In these the pyramid P Fig. 82. Fig. 83. Fig. 84. separates into two rhombohedrons, P and r, which, though geome- trically similar, are yet physically distinct. In fig. 84 the two in- dividuals are only grown together, but more commonly they penetrate each other in an irregular manner, forming apparently a single cry- stal. Twins with oblique axes are also common, the plane of union being usually one face of the rhombohedron. Thus in calc-spar two rhombohedrons are often joined by a face of JR, the two axes form- ing an angle of 127 34' ; occasionally a third individual is interposed in a lamellar form, as in fig. 85, when the two outer crystals become parallel. This latter arrangement is very common in the highly Fig. 85. Fig. 86. cleavable varieties of Iceland spar. When the crystals unite in a face of the rhombohedron R, fig. 86, they form an angle of 89 8', differing little from a right angle by which the occurrence of this law is very easily recognised, especially in prismatic varieties. In the rhombic system, twin crystals with parallel axes are very RHOMBIC MACLES. 43 rare, but those with oblique axes common, the plane of union being one of the faces of the prism o>P. Twins of this kind are very dis- tinctly seen in arragonite, carbonate of lead, marcasite, the melane or silver glance, mispickel, and other minerals. In arragonite the crystals partly interpenetrate, partly are in mere juxtaposition, as in fig. 87, where the individuals are formed by the combination ooP(M) . ooPoo (h} . Poo (k) ; and in figure 88, where several crystals of the same combination form a series with parallel planes of union ; the Fig. 87. Fig. 88. Fig. 89. M M. inner members being so shortened that they appear like mere lamellar plates producing striae on the faces Poo and coPoo of the made. In figure 89 four crystals, each of the combination ooP . 2Pco , having united in inclined planes form a circular group returning into itself. The carbonate of lead often occurs in macles in all respects similar. In staurolite individuals of the prismatic combination ooP . coPoo . OP, combine either as in fig. 90 by a face of the brachydome fPoo with Fig. 90. Fig. 91. their chief axes almost at right angles ; or as in fig. 91 by a face of 44 MONOCLINOHEDRIC MACLES. the brachypyramid |P 3 , the chief axes and the brachypinakoids (6) or the two single crystals meeting at an angle of about 60. Finally, in fig. 92 two harmotome crystals of the most common combination, oo P QO . ooPoo . P. Poo , intersect each other so nearly at right angles, that their principal axes seem to coincide, and the brachypinakoid ( Poo . Minerals differ much in the more or less facility of their cleavage, which in some is readily procured, in others only with extreme diffi- culty. The planes produced also vary much in their degree of per- fection, being highly perfect, as in mica and gypsum ; very perfect FRACTURE. HARDNESS. 55 in fluor spar, barytes, and hornblende ; perfect in augite and cryolite ; imperfect in garnet and quartz ; or very imperfect where it is scarcely perceptible. The latter is chiefly marked by the reflection of a strong light from small dispersed points on the fractured surface. In a very few crystalline minerals cleavage planes can hardly be said to exist. Cleavage must be carefully distinguished from the planes of union in twin crystals, and the division planes in the laminar minerals. When a mineral breaks in a direction different from the cleavage planes it forms fracture surfaces. These are consequently most readily observed when the cleavage is least perfect, whereas in minerals that cleave very easily, in several directions a true fracture surface can hardly be obtained. The form of the fracture is named conchoidal, when composed of concave and convex surfaces like shells ; even when nearly free from inequalities ; or uneven when marked with numerous irregular elevations and depressions. The character of the surface is smooth, when it extends uniformly with few asperities; splintery when covered by small wedge-shaped splinters adhering by the thicker end, a form most perceptible in pellucid minerals where the thinner parts are lighter coloured ; hackly, when covered by small slightly bent inequalities ; or earthy when it shows only fine dust or sandy parts. Hardness and Tenacity. The hardness of minerals, or their power of resisting any at- tempt to separate their parts, is also an important character. It appears, however, to differ considerably in the same species, ac- cording to the direction in which we attempt to scratch the crys- tal and the surface on which the trial is made. Hence its accu- rate determination is difficult, and the utmost that can usually be obtained is a mere approximation found by comparing different minerals, one with another. For this purpose Mohs has given the following scale. 1. Talc, of a white or greenish colour* 2. Rock-salt, a pure cleavable variety, or semitransparent uncrys- tallized gypsum, the transparent and crystallized varieties being gene- rally too soft. 3. Calcareous spar, a cleavable variety. 4. Fluor spar, in which the cleavage is distinct. 5. Apatite, the asparagus stone, orphosphate of lime, from Saltzburg. 6. Adularia felspar, any cleavable variety. 7. Rock-crystal, a transparent variety. 8. Prismatic topaz, any simple variety. 9. Corundum from India, which affords smooth cleavage surfaces. The Diamond. 56 TENACITY. To these Breithaupt has added two other degrees, by interposing foliated mica between 2 and 3, and scapolite, a crystalline variety,, between 5 and 6. The former is numbered 2'5, the latter 5'5. To ascertain the hardness of a mineral, first try which of the mem- bers of the scale is scratched by it, and in order to save the specimens, begin with the highest numbers, and proceed downwards, until reach- ing one which is scratched. Next take a fine hard file, and draw along its surface, with the least possible force,, the specimen to be examined, and also that mineral in the scale whose hardness is im- mediately above the one which has been scratched, in order to com- pare them together. From the resistance they offer to the file, from the noise occasioned by their passing along it, and from the quantity of powder left on its surface, their relative hardness is deduced. If the- two specimens afford the same degree of noise and resistance, and the same quantity of powder, their hardness is the same. When, after repeated trials, we are satisfied to which member of the scale of hard- ness the mineral is most nearly allied, we say its hardness (suppose it to be felspar) is equal to 6, and write after it H a= 6'0. If the mineral do not exactly correspond with any degree of the scale, but is found to be between two of them, it is marked by the lower with a decimal figure added. Thus, if more than 6 but less than 7, it is ex- pressed H = 6'5. In these experiments we must be careful to em- ploy specimens which nearly agree in form and size, and also as much as possible in the shape of their angles. Closely allied to hardness is the tenacity of minerals, of which the following varieties have been distinguished. A mineral is said to be brittle, when, as in, quartz, on attempting to cut it with a knife, it emits a grating noise, and the particles fly away in the form of dust. It is sectile or mild when, as in galena and some varieties of mica, on cutting, the particles Lose their connection in a considerable degree ; but this takes place without noise, and they do not fly off, but remain on the knife. And a mineral is said to be soft or ductile when like native gold it can be cut into slices with a knife, extended under the hammer, and drawn into wire. From tenacity it is usual to distinguish/raw^z- bility or the resistance which minerals oppose, when we attempt to break them into pieces or fragments. This property must not be confounded with hardness. Quartz is hard, and hornblende comparatively soft ; yet the latter is much more difficultly frangible than the former. Flexibility again expresses the property possessed by some minerals, of bending without breaking. They are elastic like mica, if when bent they spring back again into their former direction ; or merely flexible when they can be bent in different directions without break- ing, but remain in their new position, as gypsum, talc, asbestus, and, all malleable minerals. SPECIFIC GRAVITY. 57 Specific Gravity. The density or the relative weight of a mineral, compared with an equal volume of pure distilled water, is named its specific gra- vity. This is a most important character for distinguishing mi- Fig. 98. nerals, as it varies considerably in dif- ferent species, and can be readily as- certained with much accuracy, and, in many cases, without at all injuring the specimen. The whole process consists in weighing the body, first in air, and then immersed in water, the difference in the weight being that of an equal bulk of the latter fluid. Hence, assuming, as is commonly done, the specific gravity of water to be equal to 1 or unity, the specific gravity (G) of the other body is eqtoal to its weight in air (w>), divided by the loss or difference (d) of weight in - wat$r (or G = ^ ). One of the sim- "fifest and most portable instruments for finding the specific gravity is the areo- meter of Nicholson, fig. 98. It con- sists of a hollow cylinder C D, loaded at D with lead, so as to float upright in water at about the depth of F F. There is a cup at C, and another connected by a wire with the cylinder, at A, in which any body may be placed. In using this instrument, weights are first placed in A till it sinks in the water to the normal point marked B on the wire. The mineral is then placed in A, and the point B again brought to coin- cide with the surface of the water, by removing a portion (w} of the weights in A, which of course gives the weight of the specimen in the air. It is then removed to C, and the weight (d), which must now be added to that in A to bring the point B to the surface of the wa- ter, is equivalent to the weight of this fluid which the mineral has displaced, and the specific gravity is found by dividing the second (w) by the third (d) as above. A delicate hydrostatic balance gives the gravity with far more accuracy ; and even a good common bal- ance is often preferable. The mineral may then be suspended from one arm or scale by a fine silk thread or hair, and its weight ascer- tained first in the air and then in water. There are a few precautions necessary to insure accuracy. Thus a pure specimen must be selected, which is not intermixed with other 58 TRANSPARENCY. substances, and when weighed in air it should be quite dry. It must also be free from cavities, and care must be taken that, when weighed in water, no globules of air adhere to its surface, which render it lighter. If the body imbibes moisture, it should be allowed to remain till fully saturated before determining its weight when immersed, and it is sometimes even necessary to boil the specimen in order to expel the air from its pores. Very porous substances, like pumice, require to be pulverized before their true gravity can be ascertained. Small crystals or fragments, whose freedom from mixture can be seen, are best adapted for this purpose. The specimen experimented on should not be too heavy, thirty grains being enough where the gravity is low, and even less where it is higher. It is also of importance to repeat the trial, if possible with different specimens, which will show whe- ther any cause of error exists, and to take the mean of the whole. A correction should be made for the variation of the temperature of the water from 60 Fahr., which is that usually chosen as the standard in mineralogical works. Where the difference, however, does not ex- ceed ten or fifteen degrees, this correction may be neglected, as it only affects the third or second decimal figure of the result. Optical Properties of Minerals. There are few more interesting departments of science than the rela- tions of mineral bodies to light, and the modifications which it under- goes either when passing through them or when reflected from their surface. lu this place, however, we can only notice these phenomena so far as they point out distinctions in the internal constitution of mine- rals, or furnish characters for distinguishing one species from another. Minerals, and even different specimens of the same species, vary much in the quantity of light which can pass through them. Some transmit so much light, that small objects can be clearly seen, or let- ters read when placed behind them, and are named transparent. They are semi-transparent when the object is only seen dimly, as through a cloud ; and translucent when the light that passes through is so ob- scured that objects can be no longer discerned. Some minerals are only thus translucent on the thinnest edges, and in others even these transmit no light, and the body is named opaque or untransparent. It is apparent that these degrees pass gradually into each other, and cannot be separated by any precise line. And this is also the case in nature, where a mineral may be seen passing through the whole scale, as quartz from the fine transparent rock crystal to the opaque dark black varieties. This change generally arises from some mixture in their composition, especially of metallic substances. Minerals com- posed of minute crystalline parts are also generally less transparent DOUBLE REFRACTION. 59 than when the parts are larger or the mineral amorphous. Perfect opa- city is chiefly found in the metals or their compounds with sulphur. But even these seem to transmit light when reduced to laminae of suffi- cient thinness ; though the uniformity of the blue colour observed in thin plates of veiy different metals would rather imply that it arose from the interference of the rays passing through minute pores. Double Refraction. More important are those modifications, as double refraction and polarization, which the rays of light undergo in passing through crystals, but which have not been observed as pro- duced by amorphous bodies. As is well known, when a ray of light passes obliquely from one medium into another of different density, it is bent or refracted from its former course. The line which it then follows forms an angle with the perpendicular, which, in each body, bears a certain proportion to that at which it fell upon it, or, as de- finitely stated, the sine of the angle of refraction has always a fixed ratio to the sine of the angle of incidence, this ratio being named the index of refraction. This simple refraction is common to all trans- parent bodies, whether crystalline, amorphous, or fluid, but the greater number of crystals produce a still more remarkable result. The ray of light which entered them as one is divided into two rays, each fol- lowing different angles, or is doubly refracted. In crystals of the tesseral system this property does not exist, but it has been always observed in minerals belonging to the other systems, though in many cases only after they have been cut in a particular manner, or have been otherwise properly prepared. It is most distinctly seen in crys- tals of calc-spar, especially in the beautiful transparent variety from Iceland, in which it was first observed and described by Erasmus Bartholin in a work published at Copenhagen in 1669. The subjoined figure will illustrate this singular property. It re- presents a rhomb of Iceland spar, on the surface of which a ray of light Rr falls. 'As seen in the figure, this ray divides into two, one of which roo fol- ( lows the ordinary law of refraction, or the sines of the angles of incidence and refrac- tion maintain aopnstant ratio. This is named the ordinary ray O. The other, hence named the extraordinary ray E, 60 POLARIZATION OF LIGHT. does not obey the usual law of the sines, and has no general index of refraction, except in the plane perpendicular to the axis. In that plane it is most widely separated from the ordinary ray, but in others oblique to it approaches nearer to O, and in one at right angles coin- cides. This plane or rather direction, in which there is no double re- fraction, is named the optical axis of the crystal, or the axis of double refraction. Now, in certain minerals it is found that there is only one plane with this property, whereas in others there are two such planes, and they have in consequence been divided into monoaxial and binaxial. To the former class belong all crystals of the tetra- gonal and hexagonal systems ; to the latter all those of the three other systems. In the former the optic axis coincides with, or is pa- rallel to, the crystallographic chief axis ; in the latter the two optic axes are placed in the plane of one of the three chief sections, and generally in a symmetrical position relative to its two crystallographic axes. They also form an angle with each other, which varies, not only in different minerals, but also in the varieties of the same spe- cies. In some monoaxial crystals with double refraction, the index of refraction for the extraordinary ray E is greater than for the ordi- nary ray O ; and in others it is smaller. The former are said to have positive (or attractive), the latter negative (or repulsive) double re- fraction. Quartz is an example of the former, the index of refrac- tion, according toMalus, being for O = 1-5484, for E = 1-5582 ; and calc-spar of the latter, the index of O being = 1*6543, of E = 1-4833. The index of E is in both cases taken at its maximum. It should be observed that the optic axes are not single lines, but directions parallel to a line, or innumerable parallel lines, passing through every atom of the crystal. It is also important to remark, that this property divides the systems of crystallization into three precise groups, the tesseral forming one ; the tetragonal and hexa- gonal a second ; the other three (or four) systems the third. It is therefore of use to determine the system to which a mineral belongs. But as the angle formed by the optic axes in the several varieties of one and the same binaxial mineral species may vary very much, as is strikingly seen in topas and mica, it is of little use as a character for distinguishing species. Mitscheiiich has also shown that it varies in the same specimen with the temperature. According to Fresnel, in the binaxial crystals both rays deviate from the usual direction, so that in reality there is no longer any ordinary ray. . Polarization of Light. Intimately connected with this property is that of^he polarization of light, which, being more easily and pre- cisely observable than double refraction, is of higher value as a mine- ralogical character. By this term is meant a peculiar modification POLA1UZATION OF LIGHT. 61 which a ray of light undergoes, in consequence of which its capability of being transmitted or reflected towards particular sides is either wholly or partially destroyed. Thus, if from a transparent prism of tourin aline (the green varieties are the best) two thin plates are cut parallel to its axis, they will transmit light, as well as the prism itself, when they are placed above each other, with the chief axis of both in the same direction. But when the one slip of tourmaline is turned at right angles to the other, either no light at all or very little is trans- mitted, and the plates consequently appear black. Hence in passing through the first slip the rays of light have acquired a peculiar pro- perty, which renders them incapable of being transmitted through the second, except in a parallel position, and are hence said to be polar- ized. The same property is acquired by a ray of light when reflected, at an angle of 35^ (or angle of incidence 54|), from a plate of glass, one side of which is blackened, or from some other non-metallic body. When such a ray falls on a second similar mirror at an equal angle, but so that the plane of reflection in the second is at right angles to that in the first, it is no longer reflected, but wholly absorbed. When, on the other hand, the planes of reflection are parallel, the ray is wholly and at any intermediate angle partially reflected. A ray of light polarized by reflection is also rendered incapable of transmis- sion through a tourmaline slip in one position, which, however, is at right angles to that in which a ray polarized by passing through an- other slip is not transmitted. A prism, half an inch thick, of clove- brown rock crystal, acts in the same manner as the tourmaline, but its crystallographic chief axis must be held at a right angle to the former.* In order to observe the polarization of light, a very simple instru- Fig. 100. ment will be found use- ful, (fig. 100). At one end of a horizontal board B a black mirror a is fixed. In the middle is a pillar to which a tube cd is fast- ened, with its axis di- rected to the mirror at an angle of 35|. On the lower end is a cover c, with a small hole in the centre, and at the upper end another cover The angle of polarization varies in each reflecting surface, that given abo^64J from the perpendicular) being for glass. The plane of reflection is also named the plane of polarization, or the ray is polarized in the direction of this plane. A ray is known to be 62 POLARIZATION OF LIGHT. with a small black mirror attached to it by two arms as in the figure, and also at an angle of 35. With this instrument the mirror d can be so placed in relation to a, that the planes of reflection shall have any desirable inclination to exhibit the simple polarization of light. Its use in determining the polarizing properties of minerals de- pends on the following principles. As just stated, polarization may be produced either by reflection or transmission. Thus, when light falls on a glass plate, at the pro- per angle, part of it is reflected, part transmitted, but both portions polarized, the former in a plane parallel to the plane of incidence, the latter in a direction normal to this plane, or the two rays of light are polarized at right angles to each other. Though tourmaline, as an hexagonal or rhombohedric mineral, possesses double refraction, yet when cut as above mentioned, of a proper thickness, it only trans- mits the extraordinary ray E, polarized parallel to the basis OR. A slip of this mineral may therefore be used in place of the mirror TW, and another also in place of a, as in the experiment lately mentioned. Whenever double refraction takes place, the two rays, O and E, are polarized at right angles to each other ; O in a plane parallel, E in one normal, to the optic chief section of the surface of incidence. A simple proof of this is obtained by fixing a rhomb of calc-spar over the hole in c now placed on the upper end of the tube, an (I allowing the light to pass through it and be reflected at a. Two images of the opening c will be seen, and on turning c it will be observed that the maximum intensity of the image from O corresponds with the mini- mum from E, and the reverse. When, however, a ray of light passes through a crystal in the direction of an optic axis, the polarization of the light disappears along with the double refraction, the ray acting like common light. This property furnishes a simple test whether minerals, that cleave readily in one direction into thin lamellae, are optically monoaxial or binaxial. Place the two mirrors in the above apparatus with their polarization-planes at right angles, and fix the plate of the mineral to be tried with a little wax over the hole c, and then observe what takes place in the second mirror during the time that the cover c is turned round. If the mineral belongs to the binaxial system, the light from the first mirror a, in passing through it, is doubly refracted and has its polarization changed, and consequently can be again reflected from the second mirror, and in each revolution of c will show four maxima and four minima of intensity. If, on the contrary, the polarized if, when received on a mirror at an angle of incidence of 54J, it is found that, whilst the tnirror is once turned round, it shows two maxima and two minima of intensity of reflection. 3 MONOAXIAL AND BINAXIAL. 63 mineral is monoaxial, the ray will pass through the lamina unaltered, and will not be reflected from the second mirror in any position of c. That this must be the case is evident on the following grounds. If the lamina belongs to a mineral of the tetragonal or hexagonal systems, then its perfect cleavage planes necessarily correspond to the basis, and both the chief and optic axes are at right angles to the lamina. The ray of light consequently is neither doubly refracted nor polarized in any position of the lamina, and of course is not reflected from the second mirror. If, on the contrary, the mineral belongs to the rhombic or clinohedric systems, then its cleavage planes in general correspond either to the basis or to one of the two vertical chief sections. Hence the two optical axes lie either in the plane of the lamina or in some other plane at right angles or inclined to this plane, but neither of these axes will be vertical to the lamina. Hence the polarized light in passing through the lamina is necessarily doubly refracted, and also depolarized and consequently reflected from the second or testing mirror with four maxima and four minima of intensity. This test is very important for distinguishing among mi- nerals that like mica possess a highly perfect cleavage, the optically monoaxial from the binaxial species, and also enables us to determine the crystal-system to which they belong. Another beautiful phenomenon of polarized light, in like manner connected with the crystalline structure of minerals, is the coloured rings which lamina of the doubly-refracting species, when of a proper thickness, exhibit in certain positions. According to the undulatory theory, these rings arise from the interference of the waves of the two rays O and E ; and are easily seen in the above apparatus by inter- posing a thin plate of gypsum or mica between the two mirrors. They may also be employed to distinguish the monoaxial from the binaxial crystals. Thus when the interposed plate belongs to a mo- Fig 101. noaxial mineral, there is seen in the second mirror a system of cir- cular concentric coloured rings in- tersected by a black cross. (Fig. 101.) If, on the other hand, the mineral is binaxial, one or two sys- tems of elliptical coloured rings ap- pear, each intersected by a black stripe. (Fig. 102.) In certain cases this stripe is curved, or the two S} r stems of rings unite in a lemni- scoidal form. (Fig. 103.) When the planes of polarization are pa- PLEOCHROISM. Fig. 102. Fig. 103. rallel, the black cross and stripe appear white (fig. 104), showing that Fig. 104. in this direction the crystals act like singly- refracting minerals. Quartz again, in close relation to its tetartohedric system of crys- tallization, exhibits a circular polarization of splendid prismatic colours, which on turn- ing the plate change in each point in the order of the spectrum, from red to yellow, green, and blue. In order to produce these changes, however, in some specimens, the plate must be turned to the right, in others to the left, showing a diiference in theircrys- talline structure. But these singularly beautiful phenomena, though intimately related to the structure of minerals, have perhaps detained us too long, as the first method is the simplest and most generally applicable test. Pleochroism. Closely connected with double refraction is that pro- perty of transparent minerals which Haidinger names Pleochroism (many-coloured), in consequence of which they exhibit distinct co- lours when viewed by transmitted light in different directions. Crys- tals of the tesseral system do not show this property, whilst in those of the other systems it appears in more or less perfection ; and in the tetragonal and hexagonal minerals as Dichroism (two colours), in the rhombic and clmohedric systems as Trichroism (three colours). In LUSTRE. C5 the former or dichromatic crystals, the colours are seen in directions parallel and at right angles to the chief axes ; in the trichromatic, the rhombic crystals show them at right angles to the three axes ; and in the clinohedric system, they also are partly determined by three lines at right angles to each other. In most cases these changes of colour are not very decided, and appear rather as different tints or shades of one colour than as wholly diverse. The most remarkable of dichromatic minerals are the magnesian mica from Vesuvius, the tourmaline and pennine ; of trichromatic, the iolite, the andalusite from Brazil, the diaspore from Schemnitz, and the axinite. Some crystalline minerals exhibit a very lively play or change of colours from reflected light in certain directions. It is well seen in many various hues on the brachydiagonal cleavage planes of Labra- dor felspar ; and, according to the microscopic observations of Sir D. Brewster, is produced in this case from a multitude of very thin quad- rangular pores, interposed in the mineral like minute parallel laminae. On the macrodiagonal cleavage planes of the hypersthene it appears copper-red, and in this case, Scheerer states, is occasioned by numerous small brown or black laminae of some foreign substance, interposed in a parallel position between the planes of the hypersthene. The cha- toyant or changing colours of the sun-stone are shown by the same author to arise from scales of iron-glance similarly interposed. The play of colour in the noble opal seems, according to Brewster's obser- vations, to be produced very nearly in the same manner with that in the labradorite. He has shown that in its mass there are numerous layers of microscopic pores lying in three directions, and that the dif- ference of colour depends on the size of these pores. A similar opales- cence is seen in certain minerals when cut in particular forms. In the sapphire, cut hemispherically over the chief axis, it appears like a star with six rays ; in certain varieties of chrysoberyl and adularia it has a bluish tint ; and is also very remarkable in the cat's-eye variety of quartz. Iridescence often arises from very fine fissures, producing semicircular arches of prismatic tints, which, like the colours of thin plates in general, are referred to the interference of light. Lustre and Colour. The two principal phenomena in the mineral kingdom produced by reflected light are lustre and colour. Though, like transpa- rency, these properties admit of no precise or mathematical deter- mination, they are yet of considerable value in mineralogy. One highly-important distinction founded on them is into minerals of metallic and non-metallic aspect or character. This distinction can hardly be described in words, and the student will best learn to dis- 66 LUSTRE. tinguish metallic colours and lustre from non-metallic by observing them in nature. Transparency and opacity nearly coincide with this division, the metallic minerals being almost constantly opaque ; the non-metallic more or less transparent. Minerals which are perfectly opaque, and show metallic colour and lustre, are said to be metallic ; those with only two of these three properties are semi-metallic or metalloid ; and those with the opposite properties non-metallic. The distinction of the first and last is readily observable even in a small portion of a mineral, and is of great value both for the distinction and classification of the species. Lustre in minerals has reference to the intensity and quality of the reflected light, considered as distinct from colour. Several degrees in intensity have been named. (1.) Splendent, when a mineral reflects light so perfectly as to be visible at a great distance, and lively, well defined images are formed in its faces, as seen in galena, rock crys- tal, or calc-spar. (2.) Shining, when the reflected light is weak, and only forms indistinct and cloudy images, as seen in heavy spar. (3.) Glistening, when the reflected light is so feeble as not to be observable at a greater distance than arm's length, and the surface can no longer form an image. These two varieties are very common in many mi- nerals. (4.) Glimmering, when the mineral held near the eye in full clear day-light presents only a number of small shining points, as seen in red hematite, granular limestone, and other microcrystalline aggregates. When, as in chalk, the lustre is so feeble as to be in- discernible, it is said to be dull. In regard to the kind or quality of the lustre, the following varieties are distinguished. (1.) The metallic, as seen in much perfection in native metals and their compounds with sulphur, and imperfectly in glance coal. (2.) Adamantine, found in beautiful perfection in the diamond, and in some varieties of ruby silver, blende, and carbonate of lead ; and passing into the metallic in some opaque minerals, as the dark varieties of the red silver ore and zinc blende. (3.) Vitre- ous or glassy, as seen in rock crystal or common glass, or inclining to adamantine in flint glass. (4.) Resinous, when the body appears as if smeared with oil, as in pitch-stone and garnet. (5.) Pearly, like that of mother-of-pearl, seen in stilbite, gypsum, mica, and generally on very perfect cleavage planes. On bronzite it becomes metallic. (6.) Silky, the glimmering lustre seen on fine fibrous aggregates like amianthus. Colour. Minerals seen either by reflected or transmited light pre- sent considerable diversity of colour. This property, however, is not in all cases of equal value as a character, as the following distinctions will show. Thus some minerals are naturally coloured, or idiochro- COLOUR, 67 matic, showing, in all modes of their occurrence, a very determinate colour, which may therefore be regarded as essential to them, and forms a characteristic mark of the species. This class includes the metals, pyrites, blendes, with many metallic oxides and salts. A second class of minerals are colourless or achromatic, their purest forms being white or clear like water, with no tinge of colour, as ice, calc-spar, quartz, adularia, and many silicates. But many varieties of these minerals are occasionally coloured or allochromatic, acciden- tally tinged sometimes from the chemical or mechanical admixture of some colouring substance, as a metallic oxide, carbon, or particles of coloured minerals ; at other times from the substitution of a coloured for an uncoloured isomorphous element. The colours of these mine- rals may therefore vary indefinitely, and can never characterise the species, but only its varieties. Thus, quartz, calc-spar, fluor spar, gypsum, and felspar are often coloured accidentally by pigments me- chanically mixed ; and hornblende, augite, garnet, and other colour- less silicates acquire green, brown, red, or black tints from the intro- duction of isomorphic colouring elements. Werner, who bestowed much attention on this portion of mineralogy, distinguished eight principal colours, white, grey, black, blue, green, yellow, red, and brown, each with several varieties or shades arising from intermixture with the other colours. He also divided them into metallic and non-metallic, as follows. METALLIC COLOURS. 1. White. (1.) Silver-white is yellowish -white, as in arsenical pyrites and native silver. (2.) Tin- white is milk-white ; native antimony. 2. Grey. (1.) Lead-grey is bluish-grey ; galena or lead-glance. (2.) Steel-grey is dark ash-grey ; native platina. 3. Black. (1.) Iron-black is greyish -black ; black or magnetic iron-ore. 4. Yellow. (1.) Brass-yellow is sulphur-yellow; copper pyrites. (2.) Bronze-yellow is brass-yellow mixed with steel-grey, and a minute portion of reddish-brown ; iron pyrites. (3.) Gold-yellow is lemon-yellow ; native gold. 5. Red. (1.) Copper-red is flesh-red; native copper and copper nickel. NON -METALLIC COLOURS. 1. White. (1.) Snow-white is the purest colour, and agrees with that of new-fallen snow. Examples occur in Carrara marble and common quartz. (2.) Reddish-white is white with a slight inter- mixture of red and grey ; heavy-spar. (3.) Yellowish-white, white 68 WERNER'S SCALE OF COLOURS. with very little lemon-yellow and ash-grey ; chalk. (4.) Greyish- white is white with a little ash-grey ; quartz. (5.) Greenish-white is white with a very little emerald-green and ash-grey ; amianthus. (6.) Milk-white is snow-white with a little Berlin blue and ash-grey, or the colour of skimmed milk ; calcedony. 2. Grey. (1.) Bluish-grey is ash-grey with a little blue; limestone. (2.) Pearl-grey is pale bluish-grey with a little red ; porcelain jasper, and rarely quartz. (3.) Smoke-grey, or brownish-grey, is dark bluish -grey with a little brown, like dense smoke ; dark varieties of flint. (4.) Greenish-grey is ash-grey with a little emerald-green, and has sometimes a faint trace of yellow ; clay-slate and whet-slate. (5.) Yellowish-grey is ash-grey with lemon-yellow and a trace of brown ; calcedony. (6.) A^h-grey, the characteristic colour, is a mixture of black and white ; wood-ashes, zoisite, zircon, and slate- clay. 3. Black. (1.) Greyish-black is velvet-black with ash-grey ; basalt, lydian stone, and lucullite. (2.) Velvet-black, the charac- teristic or purest black colour; obsidian and schorl. (3.) Pitch- black, or brownish-black, is black with a little yellowish-brown ; cobalt ochre, bituminous coal, and some varieties of mica. (4.) Greenish -black, or raven black, is black with a little greenish-grey ; hornblende. (5.) Bluish-black is black with a little blue ; reniform cobalt ochre from Saalfeld, fluor spar. 4. Blue. (1.) Blackish-blue is blue with much black, and a trace of red ; dark varieties of blue copper. (2.) Azure-blue is blue with a little red ; bright varieties of blue copper and lapislazuli. (3.) Violet-blue is blue with much red, and very little black ; amethyst and octahedral fluor spar. (4.) Lavender-blue is pale violet-blue with much grey ; lithomarge and porcelain jasper. (5.) Plum-blue is blue with more red than in violet-blue, and a small portion of brown and black ; spinel and octahedral fluor spar. (6.) Berlin-blue is the purest or characteristic colour ; sapphire, rock-salt, cyanite. (7.) Smalt-blue is blue with much white, and a trace of green ; pale- coloured smalt, gypsum. (8.) Duck-blue is blue with much green, and a little black; ceylanite, talc, and corundum. (9.) Indigo-blue is a deep blue with a considerable portion of black, and a little green ; earthy blue iron or vivianite. (10.) Skye-blue, the mountain-blue of painters, is a pale blue with green, and a little white ; lenticular copper, some varieties of fluor spar, and of blue spar. 5. Green. (1.) Verdigris -green is green with much Berlin-blue and a little white ; amazon stone, and prismatic liriconite. (2.) Ce- landine-green is verdigris-green with ash-grey ; green earth, Siberian and Brazilian beryl. (3.) Mountain-green is green with much blue, WERNER'S SCALE OF COLOURS. 6 and a little yellowish -grey ; beryl, aqua-marine topaz. (4.) Leek- green is emerald-green with bluish -grey and a little brown ; common actynolite and prase. (5.) Emerald-green is the characteristic or pure green ; emerald, and some varieties of green malachite. (6.) Apple-green is green with a little greyish -white ; ehrysoprase. (7. ) Grass- green is green with a little lemon-yellow ; uranite, smaragdite. (8.) Blackish -green ; augite, and precious serpentine. (9.) Pistachio- green, the sap-green of painters, is emerald-green with yellow and a small portion of brown ; chrysolite and epidote. (10.) Asparagus- green is emerald -green with yellow and a little brown ; the apatite or asparagus stone, from Spain and Salzburg. (11.) Olive-green is grass-green with much brown and a little grey ; garnet, pitch -stone, and olivine. (12.) Oil-green is emerald-green with yellow, brown, and grey ; or pistachio-green with much yellow and light ash-grey ; olive-oil, yellow-blende, beryl. (13.) Siskin-green is emerald-green with much lemon-yellow and a little white ; uran mica and some varieties of pyromorphite. 6. Yellow. (1.) Sulphur-yellow is lemon-yellow with much emer- ald-green and white ; native sulphur. (2.) Straw-yellow is sulphur- yellow with much greyish-white ; some varieties of schorlite and car- pholite. (3.) Wax -yellow is lemon-yellow with reddish-brown and a little ash-grey ; opal and yellow lead-spar. (4.) Honey-yellow is sulphur-yellow with chestnut-brown ; dark varieties of honey, fluor spar and beryl. (5.) Lemon-yellow is the pure or characteristic colour ; rind of ripe melons, yellow orpiment. (6.) Ochre-yellow is lemon-yellow with a considerable quantity of light chestnut-brown ; yellow-earth and jasper. (7.) Wine-yellow is lemon -yellow with a small portion of red and greyish-white ; Saxon and Brazilian topaz, and octahedral fluor spar. (8.) Cream-yellow, or Isabella-yellow, contains more red and grey than the wine-yellow, and also a little brown ; bole from Strigau and compact limestone. (9.) Orange- yellow is lemon-yellow with carmine red ; rind of the ripe orange,, uran-ochre, and some varieties of molybdate of lead. 7. Red. (1.) Aurora, or morning-red, is carmine-red with much lemon-yellow ; red orpiment. (2.) Hyacinth-red is carmine-red with lemon-yellow, and a minute portion of brown ; hyacinth and dodeca- hedral garnet. (3.) Tile-red is hyacinth red with greyish-white ; fresh -burned porcelain jasper, and some varieties of foliated zeolite. (4.) Scarlet-red is carmine-red with a very little lemon-yellow ; light red cinnabar from Wolfstein. (5.) Blood-red is scarlet-red, with a small portion of black ; blood, pyrope. (6.) Flesh-red is blood-red with greyish- white ; felspar and heavy spar. (7.) Carmine-red is the characteristic colour ; carmine, spinel, particularly in thin splint- 70 ACCIDENTAL COLOURS TARNISH. ers. (8.) Cochineal-red is red with bluish-grey ; cinnabar and certain garnets. (9.) Crimson -red is red with a considerable portion of blue ; oriental ruby and cobalt bloom. (10.) Columbine-red is red with more blue, and, what is characteristic for this colour, a little black ; precious garnet. (11.) Rose-red is cochineal-red with white ; red manganese and rose-quartz. (12.) Peach-blossom-red is crimson- red with white ; blossoms of the peach, red cobalt-ochre. (13.) Cherry-red is crimson-red with a considerable portion of brownish- black; spinel, red antimony, and precious garnet. (14.) Brownish- red is blood-red with brown ; reddle, a ferruginous clay used in draw- ing, and columnar clay ironstone. 8. Brown. (1.) Reddish-brown is chestnut-brown mixed with a little red and yellow ; brown-blende from the Hartz, and pyramidal zircon. (2.) Clove-brown is brown with cochineal-red and a little black ; the clove, rock-crystal, and axinite. (3.) Hair-brown is clove-brown with ash-grey ; wood-opal and brown iron-ore. (4.) Broccoli-brown is brown with much blue and a small portion of green and red ; zircon. (5.) Chestnut-brown is the characteristic or pure brown colour; Egyptian jasper. (6.) Yellowish -brown is brown with a considerable portion of lemon-yellow ; iron-flint and jasper. (7.) Pinchbeck-brown is yellowish -brown with metallic or semi-metallic lustre; or rather the colour of tarnished pinchbeck; mica. (8.) Wood-brown is yellowish-brown with much pale ash-grey; mountain wood and bituminous wood. (9.) Liver-brown is brown with olive green and ash-grey; boiled liver, common jasper. (10.) Blackish- brown is brown with black ; mineral pitch from Neufchatel, and moor coal. The accidentally-coloured minerals sometimes present two or more colours or tints on different parts, even of a single crystal ; very re- markable examples occurring in fluor spar, apatite, sapphire, ame- thyst, tourmaline, and disthene. This appearance is still more common in compound minerals, especially the minute crystalline aggregates, on which the colours are variously arranged in points, streaks, clouds, veins, stripes, bands, or in brecciated and ruin-like combinations. The pleochroism already noticed seems a distinct phenomenon. Some minerals again change their colour in the course of time from exposure to the light, the air, or damp. Sometimes merely the surface is affected or tarnished, and then appears covered as with a thin film, producing in some minerals, as silver, arsenic, bismuth, only one colour ; in others, as copper pyrites, iron-glance, stibine, or antimony-glance, and common coal, various or iridescent hues. Occasionally, the change pervades the whole mineral, the colour sometimes becoming paler, or disappearing as in chrysoprase and rose-quartz ; at other PHOSPHORESCENCE, 71 times darker, as in brown spar, sparry iron, and manganese spar. In a few minerals a complete change of colour takes place, as in the chlorophaeite of the Western Isles, which, on exposure for a few hours, passes from a transparent yellow-green to black. These mutations seem generally connected with some chemical change. It is, how- ever, remarkable that the tarnished colours sometimes only appear on certain faces of a crystal belonging to a peculiar form. Thus a crys- tal of copper pyrites in the Berlin Museum, like fig. 38 above, has the face P' free from tarnish, the faces b and c close to P' are dark blue, the remainder of c first violet, and then close to P gold yellow. Von Kobell has produced a very beautiful tarnish on copper pyrites through galvanic influence, which may partly explain its occurrence in nature. Phosphorescence, Electricity, Magnetism, and Thermal Relations of Minerals. Phosphorescence is the property possessed by particular mi- nerals of producing light in certain circumstances different from combustion or ignition. Thus some minerals appear luminous when taken into the dark after being for a time exposed to the sun's rays, or even only to the ordinary day-light. Many diamonds and calcined barytes exhibit this property in a very remarkable degree ; less so, strontianite, arragonite, calc-spar, and chalk ; and in a still inferior degree rock-salt, fibrous gypsum, and fluor spar. In quartz and the greater number of the silicates it is wholly wanting. Many minerals, including the greater part of those thus rendered phosphorescent by the influence of the sun or insolation, also acquire it through heat. The temperature required is very different. Thus some topazes, diamonds, and varieties of fluor spar become luminous by the heat of the hand ; other varieties of fluor spar and the phosphorite require a temperature near that of boiling water ; whilst calc-spar and many silicates are only phosphorescent at from 400 to 700 Fahr. Electricity produces it in some minerals, as in green fluor spar and calcined barytes. In others it is excited when they are struck, rubbed, split, or broken ; as many varieties of zinc blende and dolomite when scratched with a quill ; pieces of quartz when rubbed on each other ; and plates of mica when suddenly separated. Though interesting, these properties are of little value in mineralogy. Friction, pressure, and heat also excite electricity in minerals, though in such of them as are conductors it is only perceptible when they are isolated. To observe this property delicate electroscopes are required, like that of Hauy, formed of a light needle, terminating at both ends in small balls, and suspended horizontally on a steel pivot 72 ELECTRICITY. by an agate cup. It can be negatively electrified by touching it with a stick of sealing-wax, excited by rubbing, or positively when the wax is only brought so near as to attract the needle. When the instru- ment is in this state, the mineral, if also rendered electric by heat or friction, will attract or repel the needle according as it has acquired electricity of an opposite or similar kind ; but if the mineral is not electric, it will attract the needle in both conditions alike. Most pre- cious stones become electrical from friction, and are either positive or negative according as their surface is smooth or rough. Pressure even between the fingers will excite distinct positive electricity in pieces of transparent double-refracting calc-spar. Topaz, arragonite, fluor spar, carbonate of lead, quartz, and other minerals show this pro- perty, but in a much smaller degree. Heat or change of temperature excites electricity in many crystals, as in those of scolezite, axinite, prelmite, boracite, tourmaline, cala- mine, topaz, titanite, calc-spar, beryl, barytes, fluor spar, diamond, garnet, and others ; which are hence said to be thermo or pyro-elec- tric. In some of these the two electricities appear in opposite parts of the crystal, and these arc said to acquire polar pyro-electricity, and the points in which they exhibit this property are named their elec- tric poles. It is remarkable that each pole is alternately positive and negative, the one when the mineral is heating, the other when it is cooling. G. Rose and Reiss name the poles that become positive during an in- crease of temperature analogue ; those that become negative in the same condition antilogue poles. This distinction will be better shown in this table. Temperature Electricity + or rising } produces in ( + or vitreous. or falling j analogue poles ( or resinous. + or rising \ in antilogue J or resinous. or falling ) poles ( + or vitreous. As already noticed, many polar electric minerals are also remarkable for their hemimorphic crystal forms, seeming to establish some causal connexion between these two phenomena. The number and distri- bution of the poles also varies. In many monoaxial minerals, as tourm aline, calamine, scolezite, there are only two poles, one at each end of the chief axis ; whereas boracite has eight poles corresponding to the angles of the cube. In prehnite and topaz again, Rose and Reiss found two antilogue poles on the obtuse lateral edges of the prism ooP, and one analogue pole corresponding to the maerodiago- nal chief section, or in the middle of the diagonal joining the obtuse edges. MAGNETISM HEAT. 73 Magnetism, or the power to act on the magnetic needle, is found in only a few minerals, of which it is very characteristic. It seems ge- nerally to depend on the presence of iron, though perhaps this is not always the case. It is either simple, attracting both poles of the needle, or polar, when by one part it attracts, by another repels the same pole. Some magnetic iron ores, or natural magnets, possess polar magnetism ; whilst the common varieties, meteoric iron, mag- netic pyrites, precious garnet, and other minerals containing much protoxide of iron, are simply magnetic. Most minerals are only at- tracted by the magnet, but are not able themselves to attract iron. M. Senarmont has recently affirmed that crystals, in conducting heat, act in a manner analogous to the phenomena they exhibit in the trans- mission of light, though the laws are not in all cases identical. In tesseral crystals heat is conducted equally in every direction, and the isothermal planes are spherical and concentric. Tetragonal and hexagonal crystals conduct alike in all directions perpendicular to the chief axis, and the isothermal planes are concentric ellipsoids of revolution. In the other three systems the conductibility varies in three directions, which in some cases have a fixed position relative to the axes, in others this has not been discovered ; and the iso- thermal surfaces are ellipsoidal figures, but not of revolution.* * Comptes Rendus, Nov. 1847, P- 708. 74 CHEMICAL PROPERTIES OF MINERALS. CHAPTER in. CHEMICAL PROPERTIES OF MINERALS. A perfect mineral species, as above stated, should possess not only a regular external form, but also a definite chemical composition. The consideration, therefore, of the chemical nature of minerals, of the elements that enter into their composition, of the manner in which these combine, and the variations in proportion which they may undergo without destroying that identity essential to the unity of the species, forms an important branch of mineralogical science. The methods of detecting the different elements in minerals, and the characters which are thus furnished for the discrimination of species, are also of much value. This is especially true of the metallic ores and some other substances, sought not as objects of curiosity, but for their economic qualities. The elementary constituents of the mineral kingdom can, indeed, only be determined quantitatively by precise and often difficult chemical analysis, but a qualitative investigation can in general be more easily accomplished by a few simple tests and reagents, which point out the true nature of the mineral, and render further chemical examination unnecessary. Composition of Minerals. A very general review of the elementary constituents of minerals is sufficient for our purpose, and a more extended description must be sought in books on chemistry. At pre- sent sixty (or sixty-two) elements, or substances which have not been decomposed, are known. Some of the most recently discovered of these, as the metals, didymium, erbium, terbium, niobium, pelopium, the ruthenium of Claus, and the new earth found by Svanberg in eudialite are so little known or their elementary character so doubt- ful, that it is unnecessary to consider them further. The remainder are divided into metallic and non-metallic, a distinction of import- ance in mineralogy, though not always to be carried out with pre- cision. The non-metallic elements are gaseous, fluid, or solid bodies, the latter rarely of semimetallic aspect, and are bad conductors of heat and electricity. Some are commonly gaseous, oxygen, hydro- gen, nitrogen, chlorine, and fluorine, one fluid, bromine, the others solid carbon, phosphorus, sulphur, boron, selenium, and iodine. The metallic elements are, except mercury, solid at usual tempera- tures, have generally a metallic aspect, and are good conductors of heat and electricity. They are divided into light and heavy metals, the former with a specific gravity under 5, and a great affinity for oxygen, and again distinguished as either alkali-metals, potassium CHEMICAL SYMBOLS. 75 (or kalium), sodium (or natrium), lithium, barium, strontium, and calcium ; or earth-metals, magnesium, lanthanium, yttrium, gluci- num, aluminium, zirconium, silicium. The heavy metals with a specific gravity above 5, are divided into noble, which can be reduced by heat alone, and ignoble, whose affinity for oxygen renders them irreducible without other agents. Some of the latter are brittle and difficultly fusible, thorium, titanium, tantalium (columbium), tung- sten (wolframium), molybdenum, vanadium, chromium, uranium, manganese, and cerium ; others are brittle and easily fusible or vo- latile arsenic, antimony, tellurium, and bismuth ; and others mal- leable zinc, cadmium, tin, lead, iron, cobalt, nickel, and copper. The noble metals are, quicksilver, silver, gold, platinum, palladium, rhodium, iridium, and osmium. All the chemical combinations observed in the mineral kingdom follow the law of definite proportions. Two substances may, indeed, unite in different quantities, but the proportion of the one to the other is either uniform, or is some multiple or submultiple of the former by a number seldom very large. As the same law prevails throughout the whole range of elements, by assuming any one, usually hydrogen or oxygen, as unity or 1, and determining from experiment the simple proportion in which the others combine with this, a series of numbers is obtained which expresses the proportions in which all these elements combine with each other. These numbers, therefore, mark the combining proportions or equivalents, as they are named, of the elements. They are also named atomic weights, on the sup- position that matter consists of definite atoms, and that its combina- tions consist of one atom (or sometimes two atoms) of one substance, with one, two, three, or more atoms of another. This theory is not free from difficulties, but the language is often convenient, and may occasionally be used. To designate the different elements, chemists now generally employ the first letter or letters of their Latin names. These signs also indicate one atom or equivalent of the element. Thus, means oxygen in the proportion of one atom ; H, hydrogen in the same proportion ; N", an atom of nitrogen ; Na, an equivalent pro- portion of natrium or sodium. These signs and the equivalent weights are given in the following table, in one column of which hydrogen is taken as unity, in the other oxygen. The numbers in the first column are those given by Naumann, chiefly after L. Gmelin, those in the column under oxygen are from Eammelsberg. The elements are arranged according to Berzelius, beginning with the most electro- positive and ending with the most electronegative, and therefore generally so that their oxides shall always be less and less electro- positive. The true place of some elements is, however, still uncer- tain, and the order thus far is only conventional. 76 ELEMENTS. TABLE I. Elements arranged in Electro- Chemical order. Name. Sign. Atomic Weight. Name. Sign. Atomic Weight. H=l U = 100. H=l = 100. Potassium ... Sodium Lithium Ammonium... Baryum . ... Strontium . . . Calcium Magnesium ... Yttrium Glucinum . . . Aluminium ... Zirconium . . Thorium Cerium Lanthanium Didymium ... Uranium Manganese ... Iron K Na NH 3 Ba Sr Ca Mg G Al Zr Th Ce La D U Mn Fe Ni Co Zn Cd Sn Pb Bi Cu Hg Ag Pd 39"2 23-2 6-4 17 68-6 44 20 12 32 4-7 13-7 22-4 59-6 46 36? 6(f 28 28 29-5 29-5 32-2 56 59 104 213 31-7 100 108 53-3 488-856 290-897 80-375 856-880 547-285 251-489 151-33 402-514 58-084 *342-334 *840402 744-900 574-718? 742-84 345-890 350-527 369-675 368'991 406-59 696-767 735-294 1294-498 *266076 395-695 1250-6 134966 665-840 Ihodium Ruthenium ... ridium 'latinum . . . Osmium Gold Rh Ru 'r Pt Os Au H srj J B Ti Ta Nb Pp W Mo V Cr Te Sb As P N Se S I Br Ct F 52 99 99 99 98 5 22-2 10-8 24 185 96 48 68-6 26-3 64 129 75 31-4 14 40 16 8 126 78-4 36 18-7 651-400 1233-260 ! 1233-260 1244-210 *2458-83 *12-479 187-5 f 277-312^ 75-00 135-983 303-686 1153-715 1183-200 598-525 855-840 328-39 802-121 1612-904 *940-084 '392-286 175-06 494-582 200-75 100 *1586-00 *999-62 *443-28 *233-800 Hydrogen ... Silicium Carbon Boron Titanium Tantalium ... Niobium Pelopium Wolframium Molybdenum Vanadium . . Chromium .. Tellurium ... Antimony . . Arsenic Phosphorus .. Nitrogen Selenium Sulphur Oxygen Iodine Bromine Chlorine Fluorine Nickel Cobalt Zinc Cadmium Tin Lead . Bismuth Copper... Mercury Silver Palladium ... In the above list Berzelins includes ammonium, usually considered a compound body, and omits the two new metals, erbium and terbium. A few minerals consist of one element in its pure state, or Math only inconsiderable and accidental admixtures. Thus the diamond and graphite are nearly pure carbon ; quartz pure silica ; sulphur and the native metals the corresponding elements. Most frequently, however, minerals consist of two or more elements combined in accordance with those laws which chemists have found to prevail in inorganic compounds, as distinguished from the organic. The most important * Double atoms. t L. Gmeliu, who considers silica as composed of one atom base and two oxygen. 4. Berzelius. CHEMICAL COMBINATIONS. 77 of these is that the combinations are binary, that is, that the elements unite in pairs, which may, however, again unite either with another compound of two, or with a single element. Hence chemists distin- guish combinations of the first, second, third order, and so on ; the combination of two elements being of the first order ; the combination of two combinations of the first order being of the second, and the combination of two of the second being of the third. In the mineral kingdom combinations of a higher order are very rare, and inorganic compounds are generally distinguished from organic by their greater simplicity. Combinations of one order with another are not unfre- quent, as of water belonging to the first with substances belonging to the second or third order. This law of binary combination seems connected with the electric character of the elements by which one is electropositive or electronegative to the others, or so that the one is attracted to the negative, the other to the positive pole. This cha- racter is only relative, and in Berzelius' arrangement each element in the series is electropositive to all that precede, and electronegative to all that follow. The following principles are observed in designating the combina- tions of these elementary substances. For those of the first order the signs of the two components are conjoined, and the number of atoms or equivalents of each expressed by a number following the sign like an algebraic exponent. Thus, SO, SO 2 , SO 3 are the combinations of one atom sulphur with one, two, and three atoms of oxygen ; FeS, FeS 2 , of one atom iron with one or two sulphur. But as combinations with oxygen and sulphur are very numerous in the mineral kingdom, Berzelius, to whom science is indebted for this system of signs, marks the atoms of oxygen by dots over the sign of the other element, and those of sulphur by an accent ; the above compounds being then wrote thus, s, s, 's, and Fe', Fe". In some cases two atoms of a base com- bine with three or five of oxygen or sulphur, as A1 2 O 3 , Fe 2 S 3 . In such cases Berzelius marks the double atom by a line drawn through the sign of the single atom, and this system has been almost univer- sally followed in foreign works. In this country, however, such types are not to be procured, and we have been obliged to adopt the sub- stitute proposed by Mr Dana, of using the thick black letter to mark the double atoms ; thus, ji is two atoms aluminium with three of oxygen or alumina ; .t>.-J<3OJOCSC5O toes o "-i ^a>oi^(No^OiCO"*co^'-( i iC^JC^l 'CQ 1 1 CO*O i(N cOr- ( oso5 i ot^ i i *O CO COOS ^ i-HCOCO-^C^-^* 1 COOt^. iO5(MCOO s{2 + - .[ si; or(c a 3, rV, MnOsi 2 , +Gu, re) si, and Mn 3 ) the mineral forms many varieties as the one or other element predo- minates. From an examination of aspasiolite, which is found at Krageroe in Norway in the form and in union with cordierite, M. Scheerer has introduced a new kind of isomorphism, which he names po- lymerous. He states that in compounds containing magnesia, protoxide of iron, oxide of nickel, and other isomorphous oxides (R () above), part of the base may be replaced by water con- taining three times as much oxygen. Thus Mg3 'si, Mg 2 si + 3 H, and Mg'si + 6 H, are isomorphous compounds, one or two atoms of mag- nesia with the same number of atoms of oxygen having been replaced by water containing three or six atoms of oxygen. Thus chrysolite and serpentine are isomorphous, the former being represented by the 84 CHEMICAL EXAMINATION OF MINERALS. first formula above, M g s sV, and the latter by the second, the general formula being in this case (liXsi silica being taken as containing three atoms of oxygen. On this supposition he has been able to give much simpler formula for many minerals than those formerly in use. But Haidinger shows that aspasiolite is probably a mere pseudomorph or product of decomposition of cordierite. Naurnann also observes that this theory requires great accuracy in determining the relative amount of the constituents, and likewise a certain agreement in cry- stalline form. It is, however, a new hypothesis, for which no proof is given, that three atoms of water have the form of one of magnesia. Scheerer's analysis, too, would be better represented by assuming that four atoms water replaced one of magnesia, and the assumption of even five atoms makes no great distinction. The new formula also are often not more probable than the old ; so that, as Rammelsberg remarks, the theory still wants that support in facts which is neces- sary for its reception. Chemical Reaction of Minerals. The object of the chemical examination of minerals is the discovery of those elementary substances of which they consist. This examina- tion is named quantitative when not only the nature of the substances but also their relative amount is sought to be determined ; and qualita- tive when the nature of the elements is alone desired. Mineralogists, appealing to chemistry chiefly as a discriminative character, are in general content with such an examination as will discover the more im- portant elements, and which can be earned on with a simple apparatus, and small quantities of the substance investigated. The indications thus furnished of the true character of the mineral are, however, fre- quently of high importance. Where the quantitative analysis of a mi- neral is wanted, more expensive apparatus and a different method of procedure are needed, for which we must refer to treatises on analytic chemistry, especially the works of G. Rose, Rammelsberg, and other authors. In mineralogy two methods of testing minerals are employed, the one by heat chiefly applied through the blowpipe, the second by acids and other reagents in solution. Use of the Blowpipe. The blowpipe in its simplest form is merely a conical tube of brass or other metal, curved round at the smaller extremity, and terminating in a minute circular aperture not larger than a fine needle. Other forms have been proposed, one of the most useful being a cone of tin open for the application of the mouth at the smaller end, and with a brass or platina beak projecting from the side near the other or broad end. With this instrument a stream of air is conveyed from the mouth to the name of a lamp or candle, so BLOWPIPE. 85 that this can be turned aside, concentrated, and directed upon any small object. The flame thus acted on is seen to consist of two parts the one nearest the beak of the blowpipe forming a blue obscure cone, the other external to this being of a shining yellow or reddish-yellow colour. The blue cone consists of the inflammable gases not yet fully incandescent, and the greatest heat is just beyond its point, where this is fully eifected. The blue flame still needs oxygen for its support, and consequently tends to withdraw it from any body placed within its influence, and is named the reducing flame. At tl*e extremity of the yellow cone, on the other hand, the whole gases being consumed and the external air having free access, bodies are combined with oxygen, and this part is named the oxidating flame. Their action being so distinct, it is of great importance for the student to learn, to distinguish accurately these two portions of the flame from each other. This is best done by experimenting on a piece of metallic tin, which can only be kept pure in a good reducing flame, and acquires a white crust when acted on by the oxidating flame. The portion of the mineral to be examined should not be larger than a peppercorn, or a fine splinter a line or two long. It is sup- ported in the flame either by a pair of fine pincers pointed with pla- tinum, or in slips of platinum foil, or on charcoal. Platinum is best for the siliceous minerals, whereas for metallic substances charcoal must be employed. For this purpose solid uniform pieces must be chosen, and a small cavity formed in the surface in which the mineral to be tested can be deposited. For fuller details on manipulation we must refer to works treating expressly on this subject.* In examining a mineral by heat, it should be first tested alone and then with various reagents. When placed alone in a matrass or tube of glass closed at one end, and heated over a spirit lamp, water or other volatile ingredients, mercury, arsenic, tellurium, often sulphur or fluorine, may readily be detected, being deposited in the cooler part of the tube or acting on the glass. It may next be tried in an open tube of glass, through which a more or less strong current of air passes according to the inclination at which the tube is held, so that volatile oxides or acids may be formed ; and in this way the chief combina- tions of sulphur, selenium, tellurium, and arsenic are detected. On charcoal, in the reducing flame arsenic, and in the oxidating flame selenium or sulphur, are shown by their peculiar odour ; antimony, zinc, lead-, and bismuth leave a mark or coloured ring on the char- coal ; and other oxides and sulphurets are reduced to the pure metal. On charcoal or in the platinum pincers the fusibility of minerals is * See Berzelius die Anwendung des Lothrohres ; Plattner die Profcirkunst mit dem Lothrohre; Griffin on the Blowpipe, &c. 86 SCALE OF FUSIBILITY. tested, and some other phenomena should be observed, as whether they intumesce (bubble up), effervesce, give out fumes, become shin- ing, or impart a colour to the flame. The degree of fusibility or the ease with which a mineral is melted should also be observed ; and to render this character more precise, von Kobell has proposed this scale : (1.) Antimony glance, which melts readily in the mere candle flame ; (2.) Natrolite, which in fine needles also melts in the candle flame, and in large pieces readily before the blowpipe ; (3.) Almandine (garnet, from Zillerthal), which does not melt in the candle flame even in fine splinters, but in large pieces before the blowpipe ; (4.) Strahl- stein (hornblende from Zillerthal) melts with some difficulty, but still more readily than (5.) Orthoclase (or adularia felspar) ; and (6.) Bronzite or diallage, of which only the finest fibres can be rounded by the blowpipe. In employing this scale, fine fragments of the test minerals, and of that to be tried, and nearly of equal size, should be exposed at the same time to the flame. A more common mode of expressing fusibility is to state whether it is observable in large or small grains, in fine splinters, or only on sharp angles. The result or product of fusion also yields important characters, being sometimes a glass, clear, opaque, or coloured ; at other times an enamel, or a mere The most important reagents for testing minerals with the blow- pipe are the following. (1.) Soda (the carbonate), acting as a flux for quartz and many silicates, and especially for reducing the metallic oxides. For the latter purpose, the assay (or mineral to be tried) is reduced to powder, kneaded up with moist soda into a small ball, and placed in a cavity of the charcoal. Very often both the soda and assay sink into the charcoal, but by continuing the operation they either again appear on the surface, or, when it is completed, the char- coal containing the mass is finely pounded and washed away with water, when the reduced metal is found in the bottom of the vessel. As a very powerful agent for reduction Fresenius recommends equal parts of carbonate of soda and cyanide of potassium (cyankalium). (2.) Borax (biborate of soda) serves as a flux for many minerals, which are best used in small splinters. The borax when first exposed to the flame swells up or intumesces greatly, and it should therefore be first melted into a small bead, in which the assay is placed. During the process the student should observe whether the assay melts easily or difficultly, with or without effervescence, what colour it imparts to the product both when warm and when cold, and also the effect both of the oxidating and reducing flames. (3.) Microcosniic salt or salt of phosphorus (phosphate of soda and ammonia) is specially im- portant as a test for metallic oxides, which exhibit far more decided 4 CHEMICAL REAGENTS. 87 colours with it than with borax. It is also a useful reagent for many silicates, whose silica is separated from the base and remains undis- solved in the melted salt. Less important are the following substances only employed for & few particular purposes. (4.) Vitrified boracic acid, used as an in- dispensable test of phosphoric acid. (5.) Gypsum and fluor spar as mutual tests, fusing together into a mass which is a clear glass when hot, but changes to a white enamel on cooling. (6.) Solution of cobalt (nitrate of cobalt dissolved in water), or dry oxalate of cobalt, serve as tests of alumina, magnesia, and zinc oxide. (7.) Oxalate of nickel forms a test of potassa where soda and lithia also occur. (8.) Tin, in slips of foil rolled up, which are dipped into the fused assay and promote complete reduction by abstracting oxygen. (9.) Iron, as harpsicord wire, used as a test of phosphorus and a mean of precipitat- ing lead, copper, nickel, and antimony, which separate from sulphur or acids when the wire is dipped in the fused assay. (10.) Silica with soda, as a test of sulphur and sulphuric acid. (11.) Oxide of copper, as a test of chlorine and iodine. In examining minerals in the moist way, the first point to be con- sidered is their solubility, as on this the whole of the procedure de- pends. Three degrees of solubility may be noted : (1.) minerals soluble in water ; (2.) minerals soluble in muriatic or nitric acid ; and (3.) those unaffected by any of these fluids. The minerals soluble in water, or hydrolytes, are either acids (almost only the boracic acid or sassolin and the arsenious acid), or oxygen or haloid salts. These are easily tested, one part of the solution being employed to find the electropositive element or basis, the other the electronegative or acid. The following bases have been found in soluble minerals, ammonia, potassa, soda, lime, magnesia, alumina, the protoxide and peroxide of iron, the oxides of zinc, copper, cobalt, uranium, and the protoxide of mercury ; the acids are, the carbonic, sulphuric, nitric, and boracic acids, to which chlorine must be added. Minerals insoluble in water may next be tested with the above acids ; the nitric acid being preferable when it is probable, from the aspect of the mineral or its conduct before the blowpipe, that it con- tains an alloy, a sulphuret or arseniate of some metal. In this manner the carbonic, phosphoric, arsenic, and chromic acid salts, many hy- drous and anhydrous silicates, many sulphurets, arseniates, and other metallic compounds, are dissolved, so that further tests may be em- ployed. The minerals insoluble either in water or these acids are sulphur, graphite, cinnabar, some metallic oxides, some sulphates, and com- pounds with chlorine and fluorine, and especially quartz, and various 88 REACTION OF NON-METALLIC BODIES. silicates. For many of these no test is required, or those furnished by the blowpipe are sufficient. The silicates and others may be fused with four times their weight of anhydrous carbonate of soda when they are rendered soluble, so that further tests may be applied.* Chemical Reaction of the more Important Elements. It is not intended in this place to describe the chemical nature of the elementary substances, and still less to enumerate the whole of those marks by which the chemist can detect their presence. Our object is limited principally to the conduct of minerals before the blow- pipe, and to a few other tests by which their more important consti- tuents may be discovered by the student. I. NON-METALLIC ELEMENTS, and their combinations with oxygen. Nitric Acid. Most of its salts detonate when heated on charcoal. In the closed tube they form nitrous acid, easily known by its orange colour and smell ; a test more clearly exhibited when the salt is mixed with copper filings and treated with concentrated sulphuric acid. When to the solution of a nitrate, a fourth part of sulphuric acid is added, and a fragment of green vitriol placed in it, the sur- rounding fluid becomes of a dark brown colour. Sulphur and its compounds, in the glass tube or on charcoal, form sulphurous acid, easily known by its smell ; the sulphuret of arsenic and mercury sublime in the closed tube ; and some other sulphurets, as iron-pyrites, part with a portion of their sulphur. The minutest amount of sulphur or sulphuric acid may be detected, by melting a very small fragment of the mineral with soda and silica, when the bead is coloured yellow or brown, from sulphuret of sodium. A surer method is to melt the pulverised assay with 2 parts soda and 1 part borax, and to lay the bead moistened with water on a plate of clean silver, which is then stained brown or black. To determine whether the mineral contains sulphur or sulphuric acid v. Kobell recommends this process : Boil the pulverised assay in a solution of potash to dry- ness, heat it till the alkali begins to melt ; dissolve and filter, and put into the filtered liquid a piece of clear silver ; this will be stained black if the mineral contained uncombined sulphur. In this way the sul- phur found in hauyne, helvine, and lapis-lazuli may be shown. In solutions sulphuric acid is best detected by chloride of baiyum (chlor- * Further information will be found in : Rammelsberg's Leitfaden fur die qualitative chemische Analyse. Berlin, 1843. Fresenius, Anleitung zur qual. chem. An., 3te Auf. Braunschweig, 1846; and especially in the classic work of Heinrich Rose, Handbuch der analytischen Chemie , 3te Aufl. Berlin, 1834. REACTION OK NON- METALLIC BODIES. 89 baryum), which forms a heavy white precipitate, insoluble in muriatic or nitric acid. Acetate of lead forms a similar deposit, soluble, how- ever, in hot, concentrated muriatic acid. Phosphoric Add. Most combinations with this acid are said by Erdmann to tinge the blowpipe flame green, especially if previously moistened with sulphuric acid. The experiment must be performed in the dark, when even three per cent, of the acid may be detected. For a larger proportion, the assay is melted with boracic acid on charcoal in the oxidating flame ; a small piece of iron wire is stuck into the melted bead, and the whole heated in the reducing flame. Phosphuret of iron is thus formed, which, when the bead after cooling is broken by a hammer, is found among the fragments as a black magnetic grain. This test, however, only succeeds when no sulphu- ric acid, arsenic acid, or metallic oxides reducible by iron are pre- sent. In solution, phosphoric acid, with muriate of magnesia, forms, on addition of ammonia, a white crystalline precipitate, which is so- luble in acids but not in sal-ammonia : the precipitate with acetate of lead also, when fused before the blow-pipe, cools into a crystallized grain. Selenium and Selenic Acid are readily detected by the strong smell of decayed horse-raddish, which even a very small quantity will pro- duce. It leaves a grey deposit with a metallic lustre on the charcoal. When roasted in the open tube, selenium is often deposited as a red sublimate. Chlorine and its salts. When oxide of copper is melted with salt of phosphorus into a very dark-green bead, and an assay containing chlo- rine fused with this, the flame is tinged of a beautiful reddish blue colour, till all the chlorine is driven off. Other salts of copper pro- duce the same colour fused alone, but not with salt of phosphorus. If very little chlorine is present, the assay is dissolved in nitric acid, (if not soluble originally it must first be melted with soda on platinum wire), and the diluted solution gives, with nitrate of silver, a preci- pitate of chloride of silver, which is first white, but on exposure to the light becomes gradually brown, and at length black. It also dis- solves readily in ammonia, but not in nitric acid. Iodine and its salts, treated like chlorine, impart a very beautiful bright green colour to the flame ; and heated in the closed tube with sulphate of potash, yield violet-coloured vapours. In solution it gives with nitrate of silver a precipitate similar to chlorine, but which is very difficultly soluble in ammonia. Its surest test is the blue colour it imparts to starch, best seen by pouring concentrated sulphuric acid over the mineral in a test tube, which has a piece of paper or cotton covered with moist starch over its mouth. H 90 REACTION OF NON-METALLIC BODIES. Bromine and its salts, treated in the same manner with salt of phosphorus and oxide of copper, colour the blowpipe flame greenish- blue. In the closed tube with nitrate of potassa they yield bromine vapours, known by their yellow colour and peculiar disagreeable smell. Treated with sulphuric acid, bromine in a few hours colours starch pomegranate-yellow. Fluorine, where it occurs accidentally in small amount, is shown by heating the assay in a closed tube with a strip of logwood paper in the open end. The paper becomes straw-yellow, and the glass is cor- roded. Where it is in large proportion, and more intimate combina- tion, this test only appears when the assay is heated in the open tube with salt of phosphorus and part of the flame admitted to the tube. Another test is to heat the pulverised mineral with concentrated sul- phuric acid in a shallow dish of platinum (or lead), over which a plate of glass covered with a coat of wax, through which lines have been drawn with a piece of sharp-pointed wood, is placed. If fluorine is present the glass is etched where exposed. Boracic Acid. The mineral is pounded, mixed with 1 part fluor spar, and 4| parts sulphate of potassa, and fused. When melting it colours the flame momentarily green. If the assay be heated with sulphuric acid, and alcohol added, and set on fire, the flame is co- loured green from the vapours of the boracic acid. Carbon, pulverised and heated with saltpetre, detonates, leaving carbonate of potassa. Carbonic acid is not easily discovered with the blowpipe, but the minerals containing it effervesce in muriatic acid, and the colourless gas that escapes renders litmus paper red. In so- lution it forms a precipitate with lime-water, which is again dissolved with effervescence in acids. Silica, before the blowpipe, alone is unchanged ; is very slowly acted on by borax, very little by salt of phosphorus, but with soda melts entirely with a brisk effervescence into a clear glass. The sili- cates are decomposed by salt of phosphorus, the silica being left in the bead as powder or a skeleton. Most of them melt with soda to a transparent glass. There are two modifications of silica, one amor- phous, and soluble in water and acids ; the other crystalline, and only acted on by fluoric acid. The former readily dissolves in a boiling solution of potassa, the latter only with much difficulty. Some sili- cates are dissolved in muriatic acid, and this the more readily the more powerful the basis, the less the proportion of silica, and the greater the amount of water they contain. Sometimes the acid only extracts the basis, leaving the silica as a powder or jelly ; or the sili- ca, too, is dissolved, and only gelatinizes on evaporation. The inso- luble silicates may be first melted with some carbonate of an alkali, REACTION OP THE ALKALIS. 91 when the solution gelatinizes, and finally leaves a dry residuum, of which the part insoluble in warm muriatic acid has all the properties of silica. II. THE ALKALIS AND EARTHS. Ammonia, heated with soda in a closed tube, is readily known by its smell. Its salts, heated with solution of potassa, also yield the vapour, known from its smell, its action on turmeric paper, and the white fumes that rise from a glass tube dipped in muriatic acid held over it. Soda is known from the reddish-yellow colour imparted to the ex- ternal flame when the assay is fused or kept at a strong red heat. In solution it is characterised rather by negative than positive marks, yielding no precipitate with chloride of platinum or sulphate of alu- mina, and with acetic acid fine needles, only when the solution is highly concentrated. Lithia is best recognised by the beautiful carmine-red colour it im- parts to the flame during the fusion of a mineral containing it in con- siderable amount. Where the proportion is small, Turner says that the same colour appears if the assay be mixed with 1 part fluor spar, and 1 parts sulphate of potassa. But the presence of soda prevents this phenomenon, so that the amblygonite, with 7 per cent, lithia, shows only a flaie of a yellow colour. In concentrated solutions it forms a precipitate with the phosphate and carbonate of soda, but none with bichloride of platinum, sulphate of alumina, or acetic acid. Potassa is known by the violet colour imparted to the external cone, when the assay is heated at the extremity of the oxidating flame. The presence of lithia or soda, however, disturbs this reac- tion. It may still be discovered by melting the assay in borax glass coloured brown by nickel oxide, which is changed to blue by the po- tassa. In concentrated solutions of potassa the bichloride of platinum gives a citron-yellow, heavy, crystalline precipitate of chloride of platinum and potassium ; acetic acid causes a white, granular, cry- stalline precipitate of binacetate of potassa ; and sulphate of alumina, after some time, forms a deposit of alum-crystals. If ammonia is also present it must first be driven oif. Potassa frequently cannot be discovered by the blowpipe, from its union with soda. When it is suspected to occur in this manner in a silicate, the assay, finely pulverized, should be melted with twice its volume of soda on charcoal, the fused mass again pulverized, dissolved in muriatic acid, evaporated, the residue dissolved in a little water, and tested as above. Baryta. The carbonate of this earth melts easily to a clear glass, 92 REACTION OF THE EARTHS. milk-white when cold ; the sulphate is very difficultly fusible, but in the reducing flame is converted into sulphuret of baryum. When combined with silica it cannot be well discovered by the blowpipe. In solution, salts of baryta yield, with sulphuric acid and solution of gypsum, immediately a fine white precipitate, insoluble in acids or alkalis ; and with silico-hydrofluoric acid a colourless crystalline pre- cipitate. Strontia, the carbonate, even in thin plates, only melts on the edges, and forms cauliflower-like projections of dazzling brightness ; the sulphate melts easily in the oxidating flame, and in the reducing flame is changed into sulphuret of strontium, which, dissolved in mu- riatic acid, and evaporated to dryness, gives a fine carmine- red colour to the flame of alcohol. In other combinations strontia must be tested when in solution. It then gives a precipitate with sulphuric acid, and with sulphate of lime, but not immediately ; and with silico- hydrofluoric acid forms no precipitate. Where it occurs along with baryta, the solution in muriatic acid should be evaporated to dryness, the residue heated to redness, pulverized and digested in alcohol, when the chloride of strontium is dissolved, the chloride of baryum left behind. Lime occurs in so many combinations, that no general rule can be given for its detection by the blowpipe. The carbonate is rendered caustic by heat, when it has alkaline properties, and readily absorbs water. The sulphate in the reducing flame changes to the sulphuret of calcium, which is also alkaline. Sulphuric acid precipitates lime only from very concentrated solutions ; oxalic acid even from very weak ones ; and silico-hydrofluoric acid not at all. As baryta and strontia also form precipitates with the first two reagents, they must previously be separated by sulphate of potassa. Chloride of calcium tinges the flame of alcohol yellowish-red. Magnesia, alone, or as a hydrate, a carbonate, and in some other combinations, when ignited with solution of cobalt, or the oxalate of cobalt, assumes a light red tint. It is not precipitated from solu- tion either by sulphuric acid, oxalic acid, or silico-hydrofluoric acid ; but phosphoric acid with ammonia throws down a white crystalline precipitate of phosphate of ammonia and magnesia. Alumina alone is infusible, but if previously moist contracts and hardens. In many combinations, when ignited with solution of co- balt, it assumes a fine blue colour. It is thrown down by potassa or soda as a white voluminous precipitate, which in excess of the alkali is easily and completely soluble, but is again precipitated by muriate of ammonia. Carbonate of ammonia also produces a precipitate which is not soluble in excess. REACTION OF METALS. 93 Glucina, Yttria, Zirconia, and Thorina are not properly distinguished by blowpipe tests, though the minerals in which they occur are well marked in this way. In solution glucina acts with potassa like alu- mina ; but the precipitate with carbonate of ammonia is again solu- ble, with excess of the alkali, and the two earths may thus be sepa- rated. Yttria is precipitated by potassa, but is not again dissolved by excess of the alkali. With carbonate of ammonia it acts like glucina. It must be observed, however, that the substance formerly named yttria is now considered a mixture of this earth with the oxides of erbium, terbium, and lanthanium. Zirconia acts with potassa like yttria, and with carbonate of ammmonia like glucina. Concentrated sulphate of potassa throws down a double salt of zirconia and potassa, which is very little soluble in pure water. In some zircons it seems mixed with noria, a new metallic oxide. III. THE METALS. Arsenic and its sulphuret on charcoal yield fumes, with a smell like garlic, and sublime in the closed tube. The greater number of alloys of arsenic in the reducing flame leave a white deposit on the char- coal ; or where it is in larger proportion, give out greyish-white fumes with a smell of garlic. Some alloys also yield metallic arsenic in the closed tube. In the open tube all of them yield arsenious acid, and those containing sulphur also sulphurous fumes. Many arsenic acid salts emit evident odours of arsenic when heated on charcoal with soda ; and some sublime metallic arsenic when heated with pulverized charcoal in the closed tube. In other compounds and salts arsenic can only be detected in solution. For this purpose the assay is melted in the platinum -spoon with three to six times its bulk of saltpetre, to form arseniate of potassa. The melted mass is then digested with water, the solution concentrated, mixed with alcohol, and treated with acetic acid till all the potassa is thrown down and the fluid gives acid reaction. When clear, it is poured off, and decomposed by nitrate of silver, which produces a reddish-brown precipitate when arsenic is present. Antimony melts easily on charcoal, emitting dense white fumes, and leaving a ring of white crystalline oxide on the support. In the closed tube it does not sublime, but burns in the open tube with white smoke, leaving a sublimate on the glass, which is easily driven from place to place by heat. Most of its compounds, with sulphur or with the other metals, show similar reaction. Antimony oxide on charcoal melts easily, fumes, and is reduced, colouring the flame pale greenish-blue. Sometimes the assay mixed with soda should be 94 REACTION OP METALS. heated on charcoal in the reducing flame when the characteristic de- posit is produced. Bismuth, melts easily, fumes, and leaves a yellow oxide on the charcoal. In the closed tube it does not sublime, and in the open tube scarcely fumes, but is surrounded by the fused oxide, which appears dark-brown when warm, and bright-yellow when cold. By these characters, and the easy reduction of its oxides, bismuth is readily recognised, even in combinations. The oxide with sul- phuretted hydrogen forms a black precipitate, and by potassa or am- monia is thrown down as a white hydrate, which is not dissolved by excess of alkali. A great addition of water produces a white preci- cipitate of very insoluble basic salt. Tellurium fumes on charcoal, and becomes surrounded by a mark with a reddish border, which, when the reducing flame is turned on it, disappears with a bluish-green light. In the closed tube tellurium gives a sublimate of the grey metal ; and in the open tube produces copious fumes, and a white powder which can be melted into small clear drops. Mercury in all its combinations is volatile, and yields a metallic sublimate when heated alone, or with tin or soda in the closed tube. Zinc, when heated with soda on charcoal, is reduced to the metallic state, but is again (and if abundant, with a bluish-green flame) con- verted into the oxide, which is deposited on the support. This de- posit, when warm, is yellow ; when cold, white ; is tinged of a fine green by solution of cobalt, and is not further volatile in the oxidating flame. In solution the surest test of oxide of zinc is its precipitation by potassa as a white gelatinous hydrate, easily redissolved in excess of the alkali, but again thrown down by sulphuretted hydrogen, as white sulphuret of zinc. Tin occurs chiefly as pyrites and tin-ore (sulphuret and oxide), and is known by the white deposit of the oxide left on the charcoal behind the assay, and which is not driven off, either by the reducing or oxidating flame, but takes a bluish-green colour from the solution of cobalt. The oxide is reduced by soda, and this even when a very small proportion of tin is present as a mere accidental element. Lead, in union with sulphur and other metals, is known by the sulphur-yellow deposit of the oxide left on the charcoal when heated in the oxidating flame. Its salts treated with soda in the reducing flame on charcoal are known both by the mark of the oxide and the re- duction of the metallic lead. The solutions of its salts are colourless, but give a black precipitate with sulphuretted hydrogen. Muriatic acid throws down chloride of lead, not acted on by ammonia, but so- REACTION OF METALS. 95 luble in a large quantity of hot water. Sulphuric acid causes a white, chromate of potassa a yellow precipitate. Cadmium, found in some ores of zinc and in greenockite, produces, with soda, a reddish-brown or orange-yellow ring on the charcoal, and also on platinum foil. Manganese, when no other metal is present to give a colour ;to the flux, is readily known by the assay melted with borax or salt of phosphorus on the platinum wire in the oxidating flame, forming a fine amethystine glass, which becomes colourless in the reducing flame. In combination with other metals, the pulverised assay mixed with two or three times as much soda, and melted in the oxidating flame on platinum foil, forms a bluish-green glass. This is the surest test of manganese, being so delicate, that even a thousandth part of the metal in the assay imparts a green colour to the flux. Potassa or ammonia throw down from solutions of its salts the protoxide of man- ganese as a white hydrate, which, in the air, becomes gradually dark- brown, and is not again dissolved by carbonate of ammonia. Cobalt is usually easily discovered. In minerals with a metallic aspect, the assay is first roasted on charcoal, and then melted with borax in the oxidating flame, when a beautiful blue glass is produced. Minerals of non-metallic aspect may be at once melted with borax. In many cases (where manganese, iron, copper, or nickel are also present) the blue colour only appears distinctly, after the glass has been for some time heated in the reducing flame. The salts of prot- oxide of cobalt form bright red solutions, from which potassa throws down a blue flaky hydrate, which becomes olive -green in the air, and can be again dissolved by excess of carbonate of ammonia. Nickel is generally very readily discovered by the assay, first roasted in the open tube and on charcoal, producing in the oxidating flame with borax a glass, which hot is reddish or violet -brown ; when cold, yellowish or dark red ; and by the addition of saltpetre changes to blue ; by which the oxide of nickel may be distinguished from that of iron. In the reducing flame the colour vanishes, and the glass appears grey, from the finely-divided particles of the metal. With salt of phosphorus the reaction is similar, but the glass is almost colourless when cold. The salts in solution have a bright green colour, and with potassa form a green precipitate of hydrated nickel- oxide, which is unchanged in the air, but again dissolved in carbonate of ammonia. Copper may in most cases be discovered by melting the assay (if apparently metallic, first roasted) with borax or salt of phosphorus in the oxidating flame, when an opaque reddish-brown glass is pro- duced, a small addition of tin aiding in the result. In the reducing 96 REACTION OF METALS. flame the glass, when warm is green, when cold blue. With soda metallic copper is produced. A small proportion of copper may often be detected by heating the assay, moistened with muriatic acid, in the oxidating flame, which is then tinged of a beautiful green colour. Solutions of its salts are blue or green, and produce a brownish -black precipitate, with sulphuretted hydrogen. Ammonia at first throws down a pale-green or blue precipitate, but in excess again produces a very fine blue colour. Cyanate of iron and potassium, even in weak solutions, gives a dark reddish-brown precipitate ; and iron throws down copper in the metallic state. Silver in the metallic state is at once known, and from many com- binations can be readily extracted on charcoal. Other combinations, and the metallic sulphurets in which it is incidentally present are thus tested. The pulverized assay, mixed with borax glass and lead, is melted by the reducing flame in a hollow of the charcoal, and then kept for some time in the oxidating flame, by which a granule of argentiferous lead is obtained. This lead is then melted by the oxi- dating flame in a small cupel of bone ashes, previously ignited, and the heat continued till it is mostly changed into litharge. The very argentiferous lead grain is now heated in another cupel, into which the lead sinks and leaves behind a grain of silver, sometimes cupreous or auriferous. From its solution in nitric acid silver is thrown down by muriatic acid as a white chloride, which in the light soon becomes black, is soluble in ammonia, and can be again precipitated from this solution by nitric acid, as chloride of silver. Gold when pure is readily known, and is easily separated from its combinations with tellurium on charcoal. If the grain is white, it contains more silver than gold, and must then be heated in a porce- lain capsule with nitric acid, which gives it a black colour, and gradually removes the silver, if the gold is only a fourth part or less. If the proportion of gold is greater, the nitro -muriatic acid must be used, which then removes the gold. From its solution in this acid the protochloride of tin throws down a purple precipitate (purple of Cassius), and the sulphate of iron, metallic gold. Platinum and the metals usually found with it cannot be separated from each other by heat. Only the Osmium-iridium strongly heated in the closed tube with saltpetre is decomposed, forming osmium acid, known from its peculiar pungent odour. The usual mixture of plati- num grains is soluble in nitro -muriatic acid, leaving behind those of osmium-iridium. From this solution the platinum is thrown down by sal-ammonia as a double chloride of platinum and ammonium. From the solution evaporated, and again diluted, with cyanide of mercury, the palladium separates as cyanide of palladium. The rhodium may REACTION OF METALS. 97 be separated by its property of combining with fused bisulphate of potassa, which is not the case with platinum or iridium. Cerium, in minerals that contain no other metal colouring the flux (especially no iron-oxide), is easily known by producing with borax and salt of phosphorus in the oxidating flame a red or dark-yellow glass, which becomes very pale when cold, and colourless in the re- ducing flame. Cerium-oxide is often combined with oxides of lan- thanium and didymium, which were confounded with it before they were recognised as independent metals. Iron, the peroxide, and hydrated peroxide, become black and mag- netic before the blowpipe. Ferruginous minerals form with borax (salt of phosphorus is similar) in the oxidating flame a dark-red glass becoming bright-yellow when cold ; and in the reducing flame, espe- cially on adding tin, an olive-green or mountain -green glass. Yet some precautions are necessary when cobalt, copper, nickel, chrome, or uranium, are also present ; and when the iron is combined with sulphur or arsenic the assay should be first roasted. Salts of pro- toxide of iron form a green solution, from which potassa or ammonia throws down the protoxide as a hydrate, which is first white, then dirty-green, and finally yellowish-brown. Carbonate of lime pro- duces no precipitate. Ferrocyanide of potassium produces a volumi- nous bluish-white precipitate becoming deep blue in the air ; whilst the femdcyanide of potassium causes a beautiful blue precipitate. The salts of the peroxide, on the other hand, form yellow solutions, from which the peroxide is thrown down by potassa or ammonia, as a flaky-brown hydrate. Carbonate of lime also causes a precipitate. Ferrocyanide of potassium produces a very fine blue precipitate ; the ferridcyanide no precipitate. Chromium. Most minerals containing this metal are distinctly characterised by forming with borax, or salt of phosphorus, a glass fine emerald green when cold, though when hot often yellowish or reddish. Usually this reaction is best seen in the reducing flame, but when oxide of lead or copper is present, in the oxidating. Where the proportion of chrome is small it must often be tested in solutions. These are usually at once known by their green colour, and the metal is thrown down by potassa as a bluish-green hydrate, again dissolved in excess of the alkali. The chrome in many minerals is very cer- tainly discovered by melting the assay with three times its bulk of saltpetre, forming chromate of potassa, which dissolved in water gives with acetate of lead a yellow precipitate of chromate of lead. Vanadium, as vanadic acid, melted on platinum wire with borax or salt of phosphorus, gives a fine green glass in the reducing flame, 98 REACTION OF METALS. which becomes yellow or brown in the oxidating flame, distinguishing it from chrome. Uranium, in most minerals, is known by yielding with salt of phosphorus, in the oxidating flame a clear yellow, in the reducing flame a fine green glass. With borax its reaction is similar to that of iron. Molybdenum, found only in a few minerals, is known by forming in the reducing flame, with salt of phosphorus, a green, with borax a brown glass, the latter separating it from other metals \vhich form a green glass with borax also. Tungsten or Wolfram occurs in minerals only as tungstic acid. It may often be known by forming with salt of phosphorus, in the oxi- dating flame, a colourless or yellow, in the reducing flame a very beautiful blue glass, which appears green when warm. When ac- companied by iron the glass is blood-red, not blue. A more gene- rally applicable test is, to melt the assay with five times as much soda in a platinum spoon, dissolve it in water, filter, and decompose the result with muriatic acid, which throws down the tungstic acid, which is white when cold, but citron-yellow when heated. Tantalium, occurring as tantalic acid, is difficultly discovered by the blowpipe. Salt of phosphorus dissolves it readily and in large quantity into a colourless glass, which does not become opaque in cooling, and does not acquire a blue colour from solution of cobalt characters at least distinguishing it from glucina, yttria, zirconia, and alumina. Its presence is best shown by the following process. Fuse the assay with two times as much saltpetre, and three times as much soda, in a platinum spoon ; dissolve this, filter, and decompose the fluid by muriatic acid : the tantalic acid separates as a white powder, which does not become yellow when heated. Titanium occurs either as the oxide or titanic acid. The latter, in anatase, rutile, brookite, and titanite, is shown by the assay forming with salt of phosphorus, in the oxidating flame, a glass which is and remains colourless ; in the reducing flame, a glass which appears yellow when hot, and whilst cooling passes through red into a beau- tiful violet. When iron is present, however, the glass is blood-red, but is changed to violet by adding tin. When titanate of iron is dissolved in muriatic acid, and the solution boiled with a little tin, it acquires a violet colour from the oxide of titanium. Heated with concentrated sulphuric acid, the titanate of iron produces a blue colour. CLASSIFICATION OF MINERALS. 99 CHAPTER IV. CLASSIFICATION OF MINERALS. IN a previous part of this treatise a mineral species was defined as a natural inorganic body, possessing a definite chemical composition, and peculiar external form. The limitations with which this defini- tion is to be understood have been pointed out in the account given of these various classes of properties. From this it appears that the form of a mineral species comprehends not only the original or fun- damental figure, but all those that may be derived from it by the established laws of crystallography. Irregularities of form, proceed- ing from accidental causes, in like manner, do not interfere with the strictness of the definition, nor yet that absence of form which results from the limited space in which the mineral has been produced. Even apparently amorphous masses, when the chemical composition remains unaltered, are properly classed under the same species, as we may suppose at least the tendency to assume the true form still to exist. The definite chemical composition of mineral species must be taken with equal latitude. Pure substances, such as they are described in works on chemistry, are very rare in the mineral kingdom. In the most transparent quartz crystals traces of alumina and iron oxide can be detected ; the purest spinel contains a small amount of silica, and the most brilliant diamond, consumed by the solar rays, leaves some ash behind. Such non-essential mixtures must be neglected, or each individual crystal would form a distinct mineral species. The iso- morphous elements introduce a wider range of varieties, and render the limitation of species more difficult. Carbonate of lime, for in- stance, becomes mixed with carbonate of magnesia or of iron, in al- most innumerable proportions ; and the latter substances also with the former. Where these mixtures are small in amount, variable in different specimens, and do not greatly afiect the form or physical characters of the predominant element, they may safely be neglected, and the mineral reckoned to that species with which it most closely agrees. Where, however, the mixture is greater, and the two sub- stances are frequently found in definite chemical proportions, these ^00 SYSTEM OF MOHS. compounds must be considered as distinct species, especially should they also show differences in form and other external characters. Amorphous minerals with definite composition must also be consi- dered as true species, though circumstances may prevent them as- suming a distinct crystalline form. But when amorphous masses show no definite composition, as in many substances classed as clays and ochres, they cannot be accounted true mineral species, and pro- perly ought not to be included in a treatise on mineralogy. Some of them, however, from their importance in the arts, others from other circumstances, have received distinct names, and a kind of prescrip- tive right to a place in mineralogical works, from which they can now scarcely be banished. Many of them are properly rocks, or indefinite combinations of two or more minerals ; others are the mere products of the decomposition of such bodies. Their number is of course in- definite, and their introduction into the system tends much to render mineralogy more complex and difficult, and to destroy its scientific character. In collecting the species into higher groups, and arranging them in a system, two wholly opposite methods have been pursued. Some have looked only at the external characters, and asserted that they alone were sufficient for all the purposes of arranging and classifying mine- rals. Others have, on the contrary, taken chemistry as the founda- tion of mineralogy, and classed the species by their composition, without reference to form or physical characters. Mohs may be re- garded as the founder and most distinguished advocate of the former school, and perhaps the only person who has ever endeavoured fully to develop such a system. With him mineralogy is a wholly inde- pendent science, which needs to borrow nothing from any other nothing from chemistry, nothing from geology, or geography. It must depend solely on external characters, of which he chooses three as especially adapted to form the basis of a system, namely, the crystalline form, the hardness, and specific gravity. Chemical characters he altogether excludes, because, as he asserts, natural his- tory cannot make use of those properties that require for their ob- servation the destruction or alteration of the body to which they be- long. Such an argument will convince few in the present day ; and even his followers now introduce -the chemical nature of the species into their descriptions, and employ chemical characters as means for their discrimination. The neglect of this most important element in the original institution of the system operated much to its preju- dice, and the author further encumbered it with a systematic nomen- clature, which has never found its way into science. The accurate study of crystallography which it demands, though in reality one of SYSTEM OF BERZELIUS. 101 the highest merits of the system, has also prevented it from ever be- coming popular. The other, no less one-sided, school regards chemistry as the only true foundation of mineralogy, which, it asserts, is in truth only one particular department, or small corner, of the larger science. The chief supporter of this doctrine is Berzelius, the celebrated Swedish chemist, whose merits in extending the chemical knowledge of mine- rals, and placing this subject on a scientific basis, can never be too highly appreciated. But even he has failed to establish a system of chemical mineralogy which has been at all generally adopted. His classification is indeed highly artificial, as is shown by the ease with which he changed the basis of the arrangement from the electroposi- tive to the electronegative element. His system, too, fails in some great requisites of a useful classification. Thus the groups which it forms are of very unequal value and extent ; the silicates, for example, comprising more than a third of the mineral kingdom, ranking with the oxalates, mellitates, and molybdates, each containing only one or two species. Again, the minerals conjoined have often very dissimilar characters, so that a knowledge of one gives us no acquaintance with the peculiarities of the others. Thus native gold, the diamond, native tellurium, antimony, arsenic, sulphur, follow in immediate succession as simple substances ; earthy cobalt, quartz, opal, sassoline, titanic acid, are conjoined on the ground of their being oxides. On the other hand, hornblende appears in five places of the system, angite in six, and the garnet in no less than nine, according to the predo- minance of different isomorphic elements. But the most important error is, we believe, the principle assumed as the foundation of the whole system, " that nothing except the composition should form an element in the arrangement of minerals." This implies that they must be regarded simply as substances, and not as individual objects, a view to which we have already stated our objections. Berzelius affirms that minerals should be arranged according to what they are (was sie sind), and not according to how they appeal- (wie sie aussehen). But here again there is an assumption made, that chemical composi- tion alone determines what a body is, and that crystalline form, hardness, gravity, colour, and similar properties, are altogether unessential, an assumption which nature does not by any means justify. A true classification of minerals should take into account all their characters, and that in proportion to their relative importance. Among these the chemical composition undoubtedly holds a high rank, as being that on which the other properties will probably be ultimately found to depend ; but it must be the general chemical cha- 102 MIXED SYSTEMS. racter, not the special electro-chemical nature of the compound. Next in order is their crystalline form, especially as exhibited in cleavage ; and then their other characters of gravity, hardness, and tenacity. But the various properties of minerals are as yet far from showing that subordination and co-relation which has been observed in the animal and vegetable kingdoms, where the external forms and structures have a direct reference to the functions of the living being. Hence even when all the characters are taken into account, there is not that facility in classifying the mineral that is presented by the other kingdoms of nature. Many, or rather most, of the species stand so iso- lated from all others, that it is scarcely possible to find any general principle on which to collect them into larger groups, especially such groups as, like the natural families of plants and animals, present im- portant features of general resemblance, and admit of being described by certain common characteristics. Hence even among those authors who have adopted what has been named the mixed system of classi- fication, in which all the characters are taken into account, conside- rable diversity prevails. Certain groups of species are indeed united by such evident characters, that they are found together in almost every method ; but other species are not thus united, and the general order of arrangement is very uncertain. It thus happens that almost every author has his own classification, and the number might be indefinitely increased. The statements just made show that the time for forming a perfect, or even nearly perfect, system of mineralogy has not yet arrived. Some, however, of very considerable merit have already been proposed, as those of Naumann, Glocker, and Weiss. We have chosen the latter, as developed by Hartmann, for the basis of that arrangement adopted in this treatise, making only such changes as the progress of the science seemed to render desirable. The general principles of this system are explained by Professor Weiss in the first volume of Kar- stein's Archiv fur Mineralogie, and by Hartmann in his Manual. The following observations, chiefly borrowed from these sources, will sufficiently exhibit its general method. A natural system must, in combining and dividing the objects which it has to classify, take account of all their properties, and assign them a place in the system, from a due consideration of their whole nature. It is this distinguishes it from an artificial system, which classifies objects with reference only to a single character. Besides species, two higher grades in classification seem sufficient at once to exhibit the natural relations, and to facilitate an easy and complete review of the species composing the mineral kingdom. These are named families and orders. In forming the families, Pro- SYSTEM OF WEISS. 103 fessor Weiss first selected those minerals which occupy the more im- portant place in the composition of rocks, and consequently in the crust of the globe. Thus quartz, felspar, mica, hornblende, garnet, among siliceous minerals ; calc-spar, gypsum, rock-salt, less so fluor spar and heavy spar, among those of saline composition, stand out prominently as the natural centres or representatives of so many dis- tinct families. To these certain metallic minerals, as iron pyrites, lead-glance, or galena, blende, magnetic iron ore, the sparry iron ore, and a few more, are readily associated as other important families. But the minerals thus geologically distinguished are not sufficient to divide the whole natural kingdom into convenient groups, and addi- tional species must be selected from the peculiarity of their natural- historical, or chemical properties. Thus the zeolites are easily seen to form such a natural group. The precious stones or gems also, notwithstanding their diverse chemical composition, must ever appear a highly natural family, when regarded as individual objects. Their great hardness, tenacity, high specific gravity without the metallic aspect, their brilliant lustre, transparent purity, and vivid colours, all mark them out as a peculiar distinct family. Only the diamond, which might naturally seem to take the chief place in this class, dif- fers so much, not only in elementary composition, but in physical properties, that it must be assigned to a diverse place in the system. Round these species thus selected the other less important minerals are arranged in groups or families. It is evident that no general de- finition of these families can be giren, as the connection is one of re- semblance in many points, not of identity in any single character. In other words, it is a classification rather according to types than from definitions, as every true natural classification must be. The same cause, however, leaves the extent of the families somewhat undefined, and also permits considerable license in the arrangement of species. But both circumstances are rather of advantage in the present state of the science, as allowing more freedom in the grouping of species than could be obtained in a more rigid system of classification. In collecting the families into orders, Professor Weiss follows rather the guidance of chemistry than of natural history, though also taking the latter into consideration. He gives chemical names to these orders, but still regards them as names, derived from the prevailing chemical characters, and not as definitions. Hence it must not be considered an error should two or three mineral species find their way into an order, with whose name, viewed as a definition, they may seem not to agree. * * " De tous les classements," says Dr Ami Boue, " tablis pour l'tude delamineralogie, aelui de M. Weiss, de Berlin, m'a paru le plus convcnable pour un cours, parce qu'il donnc 104 CLASSIFICATION OF WEISS. Guided by these and similar considerations, for which we mnst refer to his original memoir, Professor Weiss has formed the follow- ing classification of minerals. In this place we mention only the orders and families, reserving an enumeration of the species for another part of the work, where it will be more useful to the student. I. ORDER. THE OXIDIZED STONES. Families: 1. Quartz. 7. Hornblende. 2. Felspar. 8. Clays. 3. Scapolite. 9. Garnet. 4. Haloid stones. 10. Gems. 5. Zeolite. 11. Metallic stones. 6. Mica. II. ORDER. SALINE STONES. Families : I. Calc-spar. 4. Gypsum. 2. Fluor spar. 5. Rock salt. 3. Heavy spar. III. ORDER. SALINE ORES. Families: 1. Sparry iron ores. 3. Lead salts. 2. Copper salts. IV. ORDER. OXIDIZED ORES. Families: 1. Iron ores. 4. Red copper ores. 2. Tinstone. 5. White antimony ores. 3. Manganese ores. V. ORDER. NATIVE METALS. Form only one family. VI. ORDER. SULPHURETTED METALS. Families: 1. Iron pyrites. 4. Grey copper ore. 2. Galena. 5. Blende. 3. Grey antimony ore. 6. Ruby-blende. VII. ORDER. THE INFLAMMABLES. Families: 1. Sulphur. 4. Mineral resins. 2. Diamond. 5. Combustible salts. 3. Coal. la facilitd de rgunir la cristallographie et la chimie mineralogique aux groupements artificial* et naturels sur lesquels M. Mohs a base uniquement son syste"me. L'etablissement rationnel de 1'espece mineralogique est le seul but de M. Weiss, qui ensuite groupe ses especes de la maniere naturelle dont elles frappent les yeux les moins exerc^s. II cherche seulement a faciliter au commen9ant 1'etude de la science, et reconnait qui le chimiste, eomme le cry- stallographe, doivent se construire chacun un ciassement particulier." DESCRIPTION OF SPECIES. On this classification only a few additional remarks seem Though introduced into the scheme, Weiss still regards the clays and similar amorphous substances as not genuine species. In Haftmann'a treatise many of the less known minerals whose position in the system is uncertain, are placed in an appendix in alphabetical order. In the present volume these have been introduced into the system, along with the species to which they seemed most nearly allied, and on whose character they seemed to throw light. This has been done in the belief that an error in assigning them a place in a system which, like every other, is in many points only conventional, is less preju- dicial than leaving them wholly isolated. These species are rarely of much importance, and the chief doubt often was, whether they should not rather be entirely omitted. We have also felt at full liberty to alter the arrangement of the species formerly included, whenever recent investigations might require it. For such changes, which are, however, few and seldom of much consequence, the author of the present work is alone responsible. In describing the several species the following is the general plan adopted. First, that name which it seems most expedient to employ is given with such synonyms as are used in the more important English, French, and German works, especially those of Phillips, Hauy, and Mohs. Secondly, the system of crystallization is named, and the mineral more minutely characterized in the tesseral system, by enumerating the chief forms and combinations ; in the tetragonal by the dimensions of the middle edge of the fundamental form, P ; in the hexagonal, when holohedral, also by those of the middle edge of P, or when rhombohedral of the polar edge of the rhombohedron R. Rhombic minerals are described by the angles of any two of the prisms more commonly occurring, usually the prism ooP and one of the two domes, Poo or Poo , in the latter the polar edge being always the one mentioned ; more rarely the angles of the pyramid P are given. In monoclinohedric minerals the obtuse angle C, and the anterior (clinodiagonal) lateral edge of the prism coP, together with the polar edge of a hemipyramid, a clinodome, or a hemidome, are stated. In triclinohedric minerals the angles observed in the more common forms are enumerated. The forms and combinations are in general those selected by Naumann, and will be easily understood from the figures given in the former part of the treatise, but the more interest- ing and important minerals are further illustrated by figures of the crystals, mostly from Mohs and Haidinger. Thirdly, the physical properties of the mineral are described, in- cluding its state of aggregation, cleavage, and fracture, hardness (H), and specific gravity (G). Then follow its relation to light, or its 106 NOMENCLATURE. transparency, refraction, and polarization, lustre, colour, and streak ; and also its phosphorescence, electricity, and magnetism, where these properties are either peculiar or characteristic. The chemical reaction of the mineral, especially its conduct before the blowpipe (B.B.), and the effect of acids, is next noticed as important discriminating charac- ters. Its chemical compositition (Chem. Com.) or probable formula, follows, with at least the more important and recent analyses. By arranging these in a different mode from that usually adopted, we have been enabled to give more of them (in smaller space), and in a form better suited for comparison than will be found, we believe, in any other English work. For this portion of the work our principal authority has been the very elaborate and valuable treatise of Rammels- berg, the formulae of the silicates being, however, those of Naumann after L. Gmelin.* The latter part of the description includes notices of any peculia- rities regarding the species, its uses in the arts, its geognostic mode of occurrence, the most important localities where it has been found, and many other miscellaneous particulars, which could not properly be introduced in the former portion. It will thus be seen that the characteristic or determinative cha- racters of the species, are comprised in that portion of the description which precedes the analyses or the chemical composition ; whilst what follows this is miscellaneous and general information, which, though important as contributing to the complete knowledge of the species, does not yet enter into its discriminative character. The nomenclature of mineralogy is in so unsettled a state, that there is much difficulty in choosing names for the species. It is highly desirable that these names should be such as can pass current in all languages, so that in reading or consulting foreign works the student may not have always a new nomenclature to learn. In other departments of natural history a Latin terminology, with generic and specific names, has been introduced, and Breithaupt, Dana, and Glocker have endeavoured to form such a language for mineralogy. But this science seems not yet ripe for such a change ; the genera, if these exist, are still too undefined, the species too isolated from each other. Mohs gave a similar nomenclature in German, which was translated into English by Haidinger, and adopted with modifications by Pro- fessor Jameson. It has reference, however, only to his system ; and even some who retain this have, like Haidinger, returned to a more * The adoption of this view of the nature of silica, that it contains only two atoms oxy- gen, SiO 2 , is recommended by the great simplicity which it gives to the composition of many important minerals. In stating the opinions of other authors, it has, however, been occa- sionally necessary to employ the common formula for silica, or SiO 3 . NOMENCLATURE. 107 simple nomenclature. In this treatise specific names only are used, selecting as far as possible the oldest, best known, and most common. Some of these are, however, objectionable, and have been placed among the synomyms, whilst a less current term is put in the first place. We have considered it a valid objection to a specific name, that it contains a description which is either inaccurate or not cha- racteristic. Thus names like white cobalt, grey copper, magnetic iron, and many others, must be rejected, the colour being either vari- able or not peculiar, and other ores of iron being magnetic as well as the proto-peroxide. Chemical names are also inappropriate, as they belong to a different science, in which they designate a definite com- pound, which is not the case in mineralogy. As just stated, the che- mical composition of minerals is rarely pure, and one isomorphous element may replace another to a considerable extent without de- stroying the identity of the species, which in chemistry is not true. The same chemical substance also occasionally forms two minerals, and the chemical name, equally applicable to both, cannot rightly be appropriated to one. In selecting new names for such species, those used by Haidinger in his Determinative Mineralogy have generally been preferred. As the common synonyms are given at the same time, it is believed no difficulty will be occasioned by these changes. PART II. DESCRIPTION OF MINERAL SPECIES. I. ORDER. THE OXIDIZED STONES. I. FAMILY. QUARTZ. 1. Species. QUARTZ. Quarz, Werner, Hauy, &c. Rhombohedral Quartz, Mohs. Hexagonal; in common quartz apparently holohedric, but the purest varieties or rock crystal show decided tetartohedral forms (see above, p. 23). The primary pyramid P, has the middle edge = 103 34', and the polar edges = 133 44', and is often perfect. Very frequent- ly, however, it appears as a rhombohedron R (or rather P), with polar edges = 94 15'. Very common forms are coP, 3P, 4P, IIP, with the trigonal pyramids 2P2, and many varieties of trigonal tra- pezohedrons wzP ^j , the usual one being 6P|. The two latter forms are always subordinate, whilst the others with R generally determine Fig. 105. the character of the crystals, which consequently appear either prismatic, or pyramidal, or rhom- bohedric. Among the more common combina- tions are the prism terminated by the pyramid or o>P . P ; ooP . P . 4P, the forms ooP and 4P being combined in an oscillatory manner, pro- ducing stria} on the face of the prism ; ooP . P . K 2P2 )? ( fi g- 105 >) tlie last face appearing as a rhomb replacing the angles between the two other forms; and also ooP . P . ^2P2 . (GPfJ, the last face again forming a trapezium between the rhomb and the faces of the prism. In all these combinations, P is frequently divided into R and R, the latter very often entirely want- ing; and a rhombohedric character is thus im- 110 QUARTZ. [Quartz parted to the crystals, even when composed predominantly of other forms. As stated, the faces of the prism ooP are frequently striated horizontally ; those of R are often smoother and more shining than those of R. Twins or macles are common, the axes of the two crystals being pa- rallel, so that the -f R faces of the one are parallel to the R faces of the other. Sometimes the crystals are merely in juxtaposition (fig. 84 above), at other times they interpenetrate so as to form apparently only a single crystal. The crystals occur either single, attached, or imbedded, or several combined in groups and druses. Fibrous or columnar masses terminating outwards in free crystals are very common. Most fre- quently it is found granular, massive, or compact ; also in pseudo- inorphs, in petrifactions, and various other forms. The cleavage (best obtained by heating the specimen, and then cooling it suddenly in water) is rhombohedric along or parallel to R, but very imperfect ; or prismatic along o>P, but still more imperfect. The fracture is con- choidal, uneven, or splintery, H = 7 ; G = 2'5 2*8, or 2-65 in the purest varieties. Quartz is properly colourless, but more often coloured in various shades of white, grey, yellow, brown, red, blue, green, or even black. Lustre vitreous, inclining to resinous on the fracture surfaces and in some varieties. It is transparent or translucent, sometimes almost opaque. Exhibits double refraction and circular polarization. B.B. is infusible alone ; with soda effervesces and melts into a clear glass. Insoluble in acids, except the fluoric. When pulverised, slightly soluble in solution of potash. Chem. com. Si O 2 , or Si O 3 , with 48'04 silicium and 51*96 oxygen, but frequently contains a small amount of the oxides of iron or titanium, of lime, alumina, and other substances. Analyses. 1 2 3 4 5 6 Silica. Alumina. Iron perox. Lime. Manganese perox. Total. Rose. Klaproth. Do. Bucholz. Beudant. Do. 97-50 95-00 9450 98-5 95-25 94-84 0-25 1-75 2-00 0-5 0-41 0-47 0-50 0-25 0-25 10 2-66a 3-64a 1 V SO 1-50 1-CO 0-25 magnesia, 0-67 water, 1-05 98-50 9850 98-25 100- 99-89 100-00 (a) Protoxide. Many varieties of quartz have been distinguished by particular names. Thus the highly transparent colourless varieties are named rock-crystal, of which the finest specimens occur in druses in the mica slate and other rocks of Dauphin^, Switzerland, and Tyrol, in some Family. ,] QUARTZ. Ill parts of tjie Pyrenees, in Hungary, in Siberia, Brazil, Madagascar, and Ceylon. Fine, but smaller, crystals are found at Cape Diamond near Quebec, in the marble of Carrara, and in the keuper marls of Lippe. The Amethyst includes the violet-blue varieties, generally in thick columnar masses crystallized as pyramids on the exterior. The planes of union of the prismatic portions are often marked by zig-zag or undulating lines, and the colour is disposed similarly or in clouds, and all specimens showing this peculiar arrangement are now classed as amethyst. The blue colour seems to be caused by peroxide of iron. Heintz found a very dark Brazilian amethyst become colourless at 250 (cent. ?) and it contained at most O'Ol per cent, manganese, which could not be the cause of the colour. A lighter specimen from Brazil yielded 0'0197 iron peroxide, 0'0236 lime, 0-0133 magnesia, and 0*0418 soda. Another gave only 0'00273 per cent, carbon, so that organic matter can hardly produce the colour. The finest blue amethysts come from Siberia, Persia, India, and Ceylon ; white or yellow varieties (named topaz) from Brazil. Less remarkable specimens are found in Hungary and Siebenburg, and in Ireland, near Cork. The wine yellow, or citrin and gold topaz ; the brown or smoky quartz ; and the black or morion, are found in large crystals in Siberia, Bohemia, Pennsylvania, and other places. The Cairngo- rum stone from the Scottish Highlands is a brown or yellow variety. It was formerly much valued for ornamental purposes, and an Edin- burgh lapidary cut nearly L.400 worth of jewellery out of a single crystal. Less valued are the rose-quartz of various shades of red inclining to violet blue. Some ascribe the colour to manganese, in a vein of which it occurs at Rabenstein, near Zwiesel in Bavaria ; but Fuchs found 1 1'5 per cent, oxide of titanium in specimens from this locality ; whilst Berthier says, that the colouring matter of that from Quincy is of organic nature. It is also found in Finnland, Siberia, and Con- necticut. Milk quartz, milk-white and slightly opalescent, is chiefly from Greenland. Prase, leek-green, and other shades of green, often from a mixture of actinolite (see analyses 4, 5, 6 above), occurs at Breitenbrunn Saxony, Kupferberg Silesia, in the Harz, and in fine crystals on the Cedar Mountain in South Africa. Cat's eye, is greenish- white or grey, olive-green, red, brown, or yellow, and contains parallel fibres of amianthus. The finest is from Ceylon and Malabar, but also occurs at Treseburg in the Harz, Hof in Bavaria, &c. The Avanturine is yellow, red, or brown, being coloured either by scales of mica, or merely by numerous minute parallel fissures (compare oligoclase). It is found in India, in Spain, and Scotland. The Siderite is an Indigo or Berlin blue variety from Golling, in Salzburg. The fibrous quartz 112 QUARTZ. [Quartz in fine parallel fibres seems very common near the Orange river at the Cape. Common quartz is the most abundant of mineral bodies occurring either crystallized or massive, disseminated or aggregated in various forms. Its usual colour is white or grey, but other tints, as red, brown, &c., are common. It is a frequent constituent in many rocks. Some varieties are so impure or intimately mixed with other minerals as to be properly rocks rather than simple minerals. Of this kind is : (1.) The Ferruginous quartz, or iron-flint (Eisenkiesel), rendered red, yellow, or brown, from the hydrated peroxide of iron and manganese. It is often found associated with iron ores, and crystallized at Sund- vig, Westphalia, and Eibenstock, Saxony. (2.) Jasper (jaspis, Werner ; quarzjaspe, Hauy), coloured red by peroxide, yellow or brown by the hydrate of iron, but also exhibiting many other colours, as green, grey, white, and black, in some kinds alone, in others in spots, veins, and bands ; the latter the ribbon or Egyptian jasper. This mineral is abundant in rocks of various age, and in many countries ; as in Egypt, in the Ural, especially the rib- bon jasper ; the blood-red in the Tuscan Apennines ; at Kandern in Baden ; in the Harz, and in many parts of Scotland. The following is the composition of two varieties : Silica. Iron perox. Alu- mina. Lime. Water. Total. 1 2 95.76 93-57 2-74 3-98 1-50 0-31 1*05 1 : 09 100 100 Walchner from Kandern. Beudant. The porcelain jasper, produced by the action of heat on clayslate, resembles this mineral in external aspect, but is very different che- mically. (3.) Lydian stone, or flinty slate, of various black, grey, or white colours, or rarely green or brown, has a splintery or conchoidal frac- ture, and breaks into irregular more or less quadrangular fragments, often separated by veins of white quartz. It passes by many transi- tions into clay slate, and is often merely an altered portion of this rock. Two varieties gave on analysis : Silica. Alumina. Magnesia. Lime. Iron protox. Soda. Potash. Carbon. Water. Total. 99-32 100 95 1 96-50 2 61-24 0-60 1875 4-91 0-22 0-05 074 11-70 2 : 59 1-22 0-01 0-49 1-25 The iron contained traces of protox. of manganese. No. 1 is by Du Menil ; No. 2 by Schnedermann, of a specimen from Osterode in the QUARTZ FLINT. 113 Harz. Lydian stone is common in many countries, sometimes form- ing whole beds, as in Scotland. It has long been used as a touch- stone for gold, whose purity is shown by the colour of the streak ; and at Elfdal is manufactured into beautiful vases and other orna- ments. (4.) Hornstone or chert is compact, with smooth conchoidal or dull splintery fracture, translucent on the edges, and of a dirty grey, red, yellow, green, or brown colour. It passes into flint, flinty slate, or common quartz, and much resembles some compact felspars ; but is distinguished by its infusibility, B.B. It is common in many second- ary and tertiary formations, as the mountain limestone, oolite, and greensand ; and often contains petrifactions, as shells, madrepores, and wood. At Schneeberg, in Saxony, it forms pseudomorphous crystals after calc-spar. Some varieties are cut into ornamental articles, and others used for mill-stones or grinding-stones. Another class of siliceous minerals seem intermediate between quartz and opal, or as Fuchs affirms, are an intimate mixture in in- determinate proportions of crystalline and amorphous silica, the latter separable by solution of potash. Of this nature are calcedony and flint. The latter (Feuerstein, Werner ; Quarz-agate pyromaque, Hauy) occurs chiefly in the chalk formation, sometimes in beds or vertical veins, more often in irregular lumps or concretions, inclosing petri- factions, as sponges, echinites, shells or siliceous infusoria. Its colour- is greyish- white, grey, or greyish-black, also yellow, red, or brown ; sometimes in clouds, spots, or stripes. It is semitransparent, with a dull lustre and flat conchoidal fracture. The exterior coat is gene- rally white, and, according to Vaqnelin, contains from 10 to 5 per cent, carbonate of lime. The interior is more nearly pure silica, with about 1 per cent, of alumina and iron peroxide, and 1 or 2 per cent, water. The colour seems partly derived from carbon or organic matter. Heintz found in three varieties, Carbon. Water. 1. O'Ol 1-14 From Jura formation. 2. 0-066 1-103 Light coloured from chalk, Rugen. a. 0-073 1-298 Very dark, from do. In a specimen from Limhamn in Schonen, Berzelius found 0-117 pot- ash, and 0-113 of lime, with traces of iron peroxide and alumina, and a small amount of carbonaceous matter. The latter is probably de- rived from the siliceous infusoria and sponges, which, according to Ehrenberg, have furnished the chief part of the silica. Mr Bower- bank has also shown that almost all flints exhibit under the micro- scope a fibrous tissue, like that of sponges, whence he concludes that they have been formed as petrifactions of these bodies. 114 QUARTZ CALCEDONY. [Quartz Flint is very abundant in the chalk formation of northern Europe ; in the Apennine limestone of Italy, in Spain near Madrid and the mountains of Jaen, in Palestine and other countries. It was formerly much used for gun-flints, and now for the manufacture of glass and pottery. Savage nations fashion it into arrow-heads, knives, &c. ; and it is sometimes cut into cameos or other ornaments. Calcedony is semitransparent or translucent, of an even, conchoidal, or splintery fracture ; and of various white, grey, blue, green, yellow, or brown colours. It forms stalactitic, reniform, or botryoidal masses, sometimes with a curved lamellar structure. Occasionally it appears crystallized, or forms pseudomorphs or petrifactions. It is found in beds or veins, in nests, balls, and amygdaloidal cavities, in various igneous and stratified formations. Fine varieties are found at Tre- vascus mine in Cornwall, in Scotland, Hungary, Tyrol, Bohemia, Bavaria (Oberstein), in the amygdaloids of Iceland and Faroe, and many other countries. At Presztyan in Siebenburg fine smalt-blue crystals occur ; at Haytor in Devonshire it forms pseudomorphs after Datolite (the Haytorite) ; and in Cornwall pseudomorphs of fluor are common. The Carnelian includes chiefly the blood-red varieties, but also some yellow, brown, or almost black specimens. The finest come from India, Arabia, Surinam, and Siberia, but it also occurs in Bo- hemia, Saxony, and Scotland (Perthshire). In a specimen from the Gobinskoi Steppe in China, Heintz found in 100 parts, 0'081 alumina, 0-050 iron peroxide, 0'028 magnesia, 0*0043 potash, 0'075 soda, O'OOS carbon, and 0'391 water. The colouring matter seems the peroxide of iron. Those from Cambaya near Surat are originally yellow, but become red by burning, which deepens the colour, probably by pro- ducing small fissures. The Plasma is of a leek or grass-green colour, and waxy lustre. It is common among the ruins of Rome from some unknown locality ; but is found of great beauty on Olympus, and also in the Schwarzwald near Baden, and the Hauskopf near Oppenau, and is brought from India and China. The Chrysoprase of apple-green tints contains, according to Klaproth, 1 percent, nickel oxide. It is rare, but occurs at Kosemitz and other localities in Silesia, and in Vermont in North America. The Heliotrope is dark-green, sprinkled with deep-red spots, and hence is named bloodstone. It is found in Siberia, Bohemia, the Fassa Valley, and in the Island of Rum and other parts of Scotland. Agates are mixtures chiefly of calcedony in layers, with jasper, amethyst, or common quartz, and abound in the amygdaloids of our own and other countries. The colours are vari- ously disposed, and often artificially produced. In some moss agates they are probably formed by hydrates of iron or manganese ; to others an organic nature has been ascribed. The Onyx, with alternate lay- Family.} OPAL. 115 ersof white, brown , or black, was much used in ancient times for cameos. There are many other varieties of this -highly-important mineral. Some crystals are remarkable for their great size, as one in the Mu- seum at Paris, measuring 3 feet in diameter, and weighing nearly 8 cwt. Mr Allan mentions a group at Naples which weighs half a ton, and another at Milan, 3 feet long, and 5| in circumference, which weighs 870 pounds. Other specimens are remarkable from en- closing various substances, some of them crystallized. Among these are silver, copper, mispikel, silver-glance, iron pyrites, pyrargyrite, antimony-glance, rutile, cassiterite (tinstone), iron-glance, pyrrhosi- derite, magnetite, disthene, tremolite, amianthus, mica, chlorite, desminc, tourmaline, topaz, and calc-spar. Still more curious are the cavities containing air, water, naphtha, or other fluids. Some- times the cavity is only partially full, and the globule moves back- wards and forwards as in a spirit level. Sir D. Brewster mentions a specimen with a cavity seven-tenths of an inch long, and half full of fluid, and another from Quebec containing a group of calc-spar crystals, which move through the fluid on turning the specimen. Mr Allan " possesses a fragment of amethyst with four crystalline ca- vities enclosing this fluid. The largest of these is nearly half an inch in length, of which the vacuity is about one-fourth ; at a temperature of 83 the fluid dilates and fills all the cavities ; and as it reappears on cooling, an apparent ebullition is manifested." Sir H. Davy says the liquid is water with minute quantities of saline matter ; the gas azote. R. W. Fox found in crystals from a vein in the Consolidated Mines water partly tasteless or with a little common salt ; and in one crystal water very acrid, containing sulphuric acid, iron, lime, and muriatic acid, or one-tenth by weight of salts, chiefly sulphate of iron. (Compare Le Camus, N. Mem. de Dijon, 1783, p. 21 ; Brew- ster, Ed. Roy. Soc. Trans., vol. x. ; Edin. Phil. Jour., vol. ix. ; Davy, Phil. Trans, for 1822 ; Berzelius, Jahresbericht fur 1823.) 2. OPAL. Quarz resinite, Hauij ; Uncleavable quartz, Mohs. Amorphous, and without cleavage. Fracture conchoidal, or rarely even, splintery or earthy. Very brittle. H. = 5'5 6'5, G. 2 2'2. Transparent to opaque. Lustre vitreous, inclining to resinous. Co- lourless, but coloured white, yellow, red, brown, green, or grey. Some varieties exhibit a beautiful play of colours, which is destroyed by heat. B. B. decrepitates and becomes opaque, but is infusible ; in the closed tube yields water. Almost wholly soluble in solution of potash. Chem. com. silica with 5 13 per cent, water ; or probably 116 OPAL. [Quartz a mere hardened natural gelatine of silica with water as an accidental mixture. Analyses. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Silica. Watr. Alu- mina. Iron perox. Total. 90 93-13 93-50 43-50 92-00 92-00 93-00 95-5 97-48 10 5-25 5-00 7-50 775 6-33 6-13 3-0 2-52 1-62 trace. 0-13 (0-2 a) 1-00 47-00 0-25 0-38 0-8 100 100 99-50 98-0 100 9833 99-65 99-5 100-00 Klaproth, Noble O., Cscherwenitza. Do. Hydrophane, Hubertsburg. Do. Yellow 0., Telkebanya. Do. Brown-Bed O, do. Do. Fire O., Zimapan, Mexico. Bucholz, Hyalite, Frankfort. Brandes, Wood 0., Oberkassel. Schaffgotsch, Hyalite, Waltsch Bohemia. Apjohn, Hyalite, Mexico. Silica. Watr. Alu- mina. Iron perox. Potash. Soda. Lime. Mag- nesia Total. 95-32 8873 82-75 90-20 83'73 73-45 3-47 7-97 1000 2-73 11-46 12-89 0-20 0-99 3-50 1-86 3-00 (4-116) 3-58 995 0-07 f o- o'-80 0-06 v 34 o'-90 0-06 0-49 0-25 (0-31 c) 1-57 1-21 0-40 1-48 : 86 0-67 2-13 99-58 100 99-50 101-76 101-00 9963 Forchhammer Do. Stucke. Wrightson. Wertheim. Do. (a) = lime; (&) = protox. ; (c) - sulphuric acid. (10.) Cacholong from Faroe; (11.) Fire Opal from do. ; (12.) Semiopal from dolerite at Steinheim, near Hanau ; (13.) Semiopal, Schiffenberg near Giessen; (14.) Fresh, shining; and (15. ) Dull, weathered, opal from Meronitz. Forchhamraer thinks that the opal from the trap formation (10-15) must be distinguished chemically from that from the trachyte of Hungary, which is a pure hydrate of silica. Both originate from decomposition of) 90, 2Poo 35 12'. Some of the most common combinations are 4 Family ~\ ORTHOCLASE. Fig. 106. ) (M) . ooP (T, 1). OP (P) . 2P< (y) fig. 106, and OP . ( ooPao ). ooP . 2Poo . (2Poo ). The crystals appear either as short rhombic prisms when ooP pre- dominates ; or tabular when ( ooPoo ) ; or short hexagonal prismatic when ooP and ( coPco ) or rectangular prismatic when OP and ( coPoo ) predominate. Macles are frequent, especially (1.) with the twin axis parallel to the chief axis, or (2.) with it perpendicular to a face of (2Poo ), but other laws occur and some- times several are seen in one group. The first law is common in crystals from Carlsbad and Elnbogen in Bo- hemia ; the crystals often partially interpenetrating as in fig. 107 ; Fig. 107. tne second law is seen in those from Baveno. Orthoclase occurs either in crystals disse- minated singly, or attached and combined in druses, or massive in coarse and fine granular aggregates. Cleavage basal, along P, very perfect; clinodiagonal, along M, perfect ; and hemiprismatic parallel to one face of ooP in traces. Fracture conchoidal or uneven and splintery ; H. = 6 ; G. = 2-53 2-58. Transparent to translucent on the edges. Lustre vitreous, but often pearly on the more perfect cleavage planes ; and also opalescent, with bluish or changing colours, especially on the faces of ocPco . Colourless, but generally coloured in various shades of red, yellow, grey, or green. B.B. fuses with difficulty to an opaque vesicular glass ; and with salt of phos- phorus leaves silica. Solution of cobalt colours the fused edges blue. Not affected by acids. Chem. com. AI si 3 + ks'i 3 with 65*4 silica, 18 alumina, and 16'6 potash, the latter including a little soda and lime. Analyses (Table on next page). According to Abich all orthoclase from trachyte contains soda along with the potash ; C. Gmelin states the same of that from the phono- lite, and in Nos. 21, 22, the soda even predominates, as in albite. Hence Abich infers, that potash and soda must not only be isomorphous, but also dimorphous. Berthier finds, that when equal portions of orthoclase and carbonate of lime are fused together in a high tempe- rature nearly two-thirds of the potash volatilizes. The following varieties are distinguished : (1.) Adularia and ice-spar, including the transparent or translucent 120 ORTHOCLASK. [Felspar Silica. Alu- mina. Potash. Soda. Lime. Mag- nesia. Iron perox Watr. Total. 1 64 20 14 2 ... 100 Vauquelin. 2 65 20 12-25 trace. ... 1-25 ! 50 99-00 Klaproth. 3 65-69 17-97 13-99 1-01 134 trace; 100 Abich. 4 66-75 17-50 12-00 1-25 ... 075 98-25 V. Rose. 5 64-50 19-75 11-50 trace. ... 1-75 075 98-25 Klaproth. 6 65-72 1857 1402 1-25 0-34 0-10 100 Abich. 7 65-32 17-89 13-05 2-81 0-10 0-09 : 3to 99-75 Do. a 65-91 20-93 10-18 3-50 0-11 ... 100-63 Moss & Litton. 9 6582 19-01.' 12-25 3-30 0-34 0-07 100-78 Do. 10 66-43 17-03 13-96 0-91 1-03 : 49 99-85 Kroner. 11 65-52 17-61 12-98 1-70 094 0-80 99-55 Kersten. 12 68 15 14-50 ... M 0-50 98-00 Klaproth. 13 66-6 18-5 80 4-0 i-o 0-6 987 Berthier. 14 70-00 16-50 11-50 * 0-25 98-25 Klaproth. 15 65-52 19-15 14-74 b 060 k . 100 G. Rose. 16 661 19-8 6-9 37 .*. 2-0 98-5 Berthier. 17 6B73 17-36 8-2? 4-10 1-23 1-20 0-81 99-00 Abich. 48 65-OOe 18-64 9-12 3-49 1-23 1-03 0-83^ 99-49 Do. 19 67-87 1572 6-68 2-8.J 3-16 1-40 2-41 100-10 Do. 20 64-86 21-46 2-62 10-29 trace. trace. trace. 99-23 Schnederman. 21 64-86 21-92 4-15 7-53 trace. trace. 98-46 Do. 22 66-82 17-58 14-80 o!o9 99-29 Plattner. 23 65-76 18-31 14-06 ... 1 : 20 trace. 99-33 Evreinoff. 24 68-6 16-6 14-8 ..* 100 R. Phillips. 25 67-90 18-00 7-50 i : oo 3 : 25 270 1*00 101-35 Thomson. (a) With copper oxide, + 0'19 manganese perox ; (6; with a little soda and loss ; \c) + trace of titanic acid; (d) -f- 0-13 manganese perox. Nos. 1, 2, 3, are theadularia Variety, from (2) Friedrichsvarn, Norway; (3) St Gotthardt. Nos. 4-11, common orthoclase or felspar. 14) flesh-coloured from Lomnitz; (5) near Carls- bad; (6)Baveno; (7) Siberia, (the amazon-stone) ; (8) Alabaschka; (9) Schaitansk; (10) flesh-red from veins of tin ore near Marienberg, G = 2-44; (11) gneiss at Freiberg. Nos. 12-21 glassy felspar or sanidine from (12, 13) Drachenfels, Rhine; U4) the peperino near Rome; ( 15) Vesuvius ; (16) Mont d' Or; (17) Eporneo Ischia; (18) Arso Ischia; (19) tufa of Pausilipo; (20, 21) basalt of the Hohen-Hagen between Gottingen and Miinden. No. 22, Valencianite ; (23) mikrokline from Arendal ; (24) Murchisonite, Dawlish; (25) erythrite, Kilpatrick Hills, Glasgow. varieties, with splendent lustre, and either colourless and white, or only slightly-tinged grey, green, yellow, red, or brown. Some with a bluish opalescence are named moonstone. It sometimes occurs as a constituent of granite, syenite, and gneiss ; but more common in veins and druses in similar rocks near St Gotthardt, in Mont Blanc, Dauphine, and at Arendal. Beautiful specimens with changing co- lours occur in Ceylon, in the zircon-syenite of Norway, the Micro- clirie of Breithaupt, and in Greenland. The Valencianite of Breithaupt from Valenciana in Mexico seems only adularia. (2.) Common felspar is less splendent and transparent, and gene- rally white or red, especially flesh-red in colour. The Amazon- stone is a verdigris-green variety (anal. 7), from Lake Ilmen in the Ural, near Miask, coloured by copper oxide. Felspar is a very com- mon constituent of many rocks. Fine attached crystals are found at Baveno on Lago Maggiore, at Lomnitz in Silesia, in many parts of the Ural, in Ireland, and in Aberdeenshire Scotland. Imbedded crystals of great beauty occur at Carlsbad and Elnbogen, Bohemia, in Family. ,] ORTHOCLASE. 121 the Fichtelgebirge, and in Brazil. The Morchisonite of Levy, cha- racterised by a golden or greyish-yellow tint, from the granite of Arran and from Dawlish (anal. 24), seems a mere variety, and Thom- son's Erythrite (anal. 25) is also scarcely distinct. Fig. 108. Macles of Common Felspar. (3.) The glassy felspar or sanadine is by some consider- ed a distinct species, charac- terised by the presence of four per cent, or more of soda; and also differing slightly in an- gular measurement (C = 63 55', oo P 119 13'); but the forms and combinations are nearly the same with those of orthoclase. The crystals are imbedded, greyish or yellow- ish white, or grey ; vitreous lustre ; transparent or trans - RIGHT. LEFT. lucent, and often much crack- ed or fissured. It seems to characterise the volcanic and similar igneous rocks, as trachyte, pitch-stone, pearl-stone, and obsidian, whilst the adularia and common felspar are found in the plutonic and metaniorphic rocks. Very fine crystals occur in the trachyte at Drach- enfels on the Rhine, at Mont d'Or and other parts of Auvergne, in Mexico, and Chili ; and of less beauty in that of Hungary, Milo, and the Euganean hills. It is found in trachytic lavas in Italy at Monta- miato, Pozzuolo, Ischia, &c., in Iceland, and other countries. In the basalt of the Hohenhagen near Gottingen, it seems to have been ori- ginally common felspar but altered by heat, a change seen in the walls of some furnaces formed of eurite -porphyry. It is common in the ejected blocks on Vesuvius with hornblende, and at Lake Laach. Also, it is said, in Arran, Rum, and other parts of Scotland. Orthoclase has been known to form artificially, as in the copper furnaces of Mansfeld, where, besides silica, alumina, and potash, it contains traces of peroxide of manganese and lime. It has also been found in the iron furnaces at Stolberg in the Harz, by the younger Hausmann, in small single or macled crystals, like adularia. Orthoclase is one of the most important constituents of the crust of the globe, occurring not only in granite, gneiss, and porphyry, but in many secondary formations composed of their debris, as in grey- wacke, and some sandstones and conglomerates. In rocks it is very commonly associated with quartz, sometimes as a mere granular mix- ture ; at others, as in the graphic granite of Portsoy and Aberdeen- 122 RYACOLITE. [Felspar shire, regularly combined. In Bennachie the crystals of orthoclase contain imbedded grains of quartz. Mica and chlorite also commonly accompany it ; and large crystals of orthoclase are often covered with small ones of albite. This mineral is very liable to decomposition, when it is converted especially into kaolin. It first loses its lustre and transparency, be- comes paler in colour, whilst its hardness and gravity dimmish, and at length falls down into a white earth. In this process the potash forms with four atoms silica (ks) a soluble silicate, which is removed, and leaves A! si 2 in combination with two atoms water. In this manner the rocks containing it are destroyed, a loose soil formed, and the alkali essential to the life of plants brought within their reach. The kaolin is used for manufacturing porcelain and stoneware. Some felspars are cut as ornamental stones, as the adularia or moonstone, and the green amazon stone. Compact Felspar or Feldstein seems generally a mixture of ortho- clase and quartz. It is often harder than the pure mineral, with G. = 2*59 3. Its colour is white, grey, red, or yellow, sometimes in spots or bands. The softer varieties are named claystone, and often show bluish or purplish tints, with G. = 2'21. B.B. most of them melt with difficulty to a white enamel, when the small grains of quartz often appear. This distinguishes it from hornstone, which is infusible. It is a common constituent in the porphyry rocks of many countries, as of the Cheviots, Pentland, and Ochil hills in Scotland. Sweden also contains many varieties, of which the leelite from Gry- thyttan has been made a separate species, but is a distinct mixture of very uncertain composition. Analyses. Silica. Alu- mina. Potash. Lime. Mag- nesia. Iron perox. Watr. Total. 1 75-20 15-00 3-40 1-20 2-40 ... 1-50 9870 Berthier, Nantes. 2 7M7 1360 3-19 0-40 0-10a 1-40 3-50 93-36 Mackenzie. 3 79-00 11-50 600 1-25 1-00 99-75 Klaproth. 4 80-00 12-00 5-00 ... 1-50 0-50 90-00 Do. 5 73-50 15-00 6-50 1-00 tracea 1-50 0-75 99-25 Do. 6 81-91 655 8-88 6'42& 103-76 Thomson. 7 75-0 22-0 2-5 a 0-5 100 Clarke. 8 76-45 14'88 6-60 ... 0-90c 0-93 99-76 Schafhautl. (a) = Manganese perox. ; (6) = iron protox. ; (c) perox. of iron and manganese. From (1) Nantes ; (2) Pentland Hills; (3, 4, 5, Weisstein) (3) Pacheralp; (4) Schemnitz; (5) Reichenstein ; (6, 7) Leelite Grythyttan ; (8) Claystone. (4.) RYACOLITE, G. Rose. Empyrodoxer Feldspath, Mohs; Ice-spar in part. Monoclinohedric ; C == 63 54', ooP 119 21', Poo 65 37' (2P), 90 32' ; usual combination, ( ooPoo ) . ocP . ( ooP3) . OP . 2Poo . (2Poo ); the crystals are thick tabular, or short prismatic, and either dissemi- Family.] ALBITE. 123 nated singly or united in small druses. Macles occur with the twin axes parallel to the chief axis, and united by a face of ( ooPoo ) ; and also united by (2Pco ), forming four-sided prisms. Cleavage basal and clinodiagonal ; both almost equally perfect, H.=6; G.=2'57 2*58 (to 2-618, G. Kose). Transparent or translucent ; lustre vitreous ; colour white or grey. B. B. melts easier than orthoclase, tinging the flame yellow. Imperfectly soluble in muriatic acid, leaving silica in powder. Chem. com. labradorite. Analysis. si 2 + B s\, and hence analogous to that of 1 Silica. Alu- mina. Soda Potash. Lime Mag- nesia. Iron perox. Total. 50-31 29-44 10-56 5-92 1-07 0-23 0-28 | 97-81 G. Rose. Found with augite, mica, and nepheline in ejected blocks on Vesu- vius (anal. 1), and near Lake Laach. Many so-called glassy felspars probably belong to this species. 5. ALBITE, Eggertz, G. Rose, Phillips, Sfc. ; Schorl blanc, Rome de risle. Cleavelandite, Brooke; Tetartoprismatic Felspar, Mohs. Pericline, v. Leonhard, Phillips, fyc. ; Heterotomous Felspar, Mohs. f Triclinohedric ; OP (P) to ooPoo (M) = 86 40', ooP' (/) to oo'P Fig. 109. (T) = 121 38'. The M crystals have a general resemblance to those of orthoclase, and many of the forms differ but very little. They are usually tabular when ooPoo , or prismatic when coPoo, and OP predominate (fig. 109). Macles are very common according to se- veral laws, especially united by a face of ooPoo , (fig. 110), the re-entering angle between the faces of OP (P and P' = 173 20') being very characteristic of triclinohedric felspars. Another made common in the pericline variety is repres'ensed in fig. Ill, (compare p. 44 above). These macles are often repeated, forming polysynthetic crystals ; or two macles are united according to the same law as the Carlsbad macles of ortho- clase (No. 1 above). Also found massive and in granular foliated or radiating aggregates. Cleavage basal and brachydiagonal, almost 124 ALBITE. [Felspar equally perfect ; prismatic along ooP imperfect. Fracture conchoidal Fig. 110. Fig. 111. \ M or uneven, H. = 6 6'5 ; G. = 2'6 2 - 67. Rarely transparent in small crystals, usually translucent or only on the edges. Lustre vitreous, inclining to pearly on the cleavage planes, especially OP. Colourless, but generally white, grey, green, red, or yellow. Streak white. B.B. difficultly fusible, tinging the flame yellow, to a white semiopaque glass. Not affected by acids. Chem. com. A! si 8 + Na s' 8 with 69-3 silica, 19-1 alumina, and 11-6 soda, part of the last often replaced by lime or potash. Silica. Alu- mina. Soda. Pot- ash. Lime. Mag- nesia. Iron 3erox. Manga, perox. Total. 1 70-48 18-45 10-60 0-55 99.98 Eggertz. 2 67-75 18-65 10-06 ... 0-34 o'-95 0-25 98-00 Ficinus. 3 70-68 19.80 9-06 ... 0-23 0-11 99-88 Stromeyer. 4 68-46 19-30 9-12 0-68 trace 0-28 97-84 G. Rose. 5 68-45 18-71 11-24 0-65 0-50 0-18 0-27 trace a 11)0 Abich. 6 69-11 19-34 10-98 0-65 trace trace 0-62 trace a 100-70 Erdmann. 7 6875 18-70 10-90 1-21 0-39 0-09 0-90 100-94 Lohmeyer. 8 67-39 19-24 6-23 6'77 0-31 0-61 ... 100-55 Brooks (m. of 2). 9 66-11 18-96 9-24 0-57 3-72 0-16 o'-34 99-10 Scheidhauer (m. of 4). 10 67-92 18-50 8-01 2-55 0-85 042 0-50 98-75 Kersten. 11 67-94 18-93 9-99 2-41 0-15 0-48 (0-36)6 100-26 C. Gmelin. 12 69-00 19-43 11-47 0-20 ... 100-10 Thaulow. 13 68-23 18-30 7-99 2-53 1-26 0-51 l'-01 99-83 Abich. 14 70-22 17-29 5-62 3-71 2-09 0-41 0-82 100-15 Do. 15 71-60 14-75 10-06 0-32 1-06 trace 1'41 trace a 99-20 Schnedermann. (a) Protoxide ; (6) loss by heat. Nos. 1-10, albite; 11-13, pericline. From (1) Finbo; (2) Pennig, Saxony; (3) Chesterfield'' North America ; (4) Arendal; (5) Miask in greenstone, G. =2-624; (6) Brevig, Norway, (7) Biesengebirge from granite veins in oligoclase-granite, G. = 2-624 ; (8) St Gotthardt, snow-white, mean of two, but perhaps mixture with orthoclase; (9) Snarum, Norway, white crystallized, mean of four analyses ; (10) Deep Fiirstenstolle Freiberg ; (11) Zoblitz, compact pericline; (12) St Gotthardt, crystallized; (13) Pantellaria in trachyte, G. =2-595. 14, Basis of Draehenfels' trachyte, portion insoluble in acids. 15, Adinole from Lerbach. The above analyses show that there is no essential chemical dis- tinction between albite and orthoclase, soda and potash being found in both, only in general in somewhat different proportions. As stated Family.'} ANDESIN SACCHARITE. 125 above, their crystalline forms also resemble, and the angles of albite sometimes vary, so as to approach more closely to those of orthoclase. On this ground Breithaupt and Mohs have separated pericline from albite, making the inclination of P: M = 86 41', and I : T = 120 37', differences from the above such as may occur in the same species, especially as the angles are not readily measured. The chemical composition shows no distinction, and the specific gravity (= 2'54 2 -595) is less characteristic than was imagined. Albite is less common than orthoclase ; but is a constituent of many greenstones (as near Edinburgh), and sometimes of granite, syenite, gneiss, porphyry and trachyte, or occurs in beds and veins in these rocks. Fine crystals are found at Bareges in the Pyrenees, Bourg d'Oisans Dauphine, St Gotthardt, in the Tyrol, Salzburg, and in Norway at Arendal. Small crystals occur in the Harz, and fine massive varieties at Pennig and Zoblitz in Saxony, Finbo near Fah- lun, Haddam Connecticut, and Chesterfield Massachusetts. Adinole of Beudant is merely a compact mixture of albite and quartz of various dirty white, grey, or red colours. It is found at Sala in Sweden, Lerbach in the Harz, and other places. In aspect and mode of occurrence it resembles compact felspar. 6. ANDESIN, Abich. Triclinohedric ; forms of crystals similar to albite, but the cleavage less distinct ; G. = 2'7328. Colour and other physical properties like albite. B.B. more easily fusible (like oligoclase) to a milky somewhat porous glass. Chem. com. AI s'i 2 -f- B si 2 ; where R is nearly one-half soda and one-half lime. Analysis. 1 2 Silica. Alu- mina. Soda. Pot- ash. Lime. Mag- nesia. Iron perox Total. Abich. Francis. 59-60 5672 24-28 26-52 6-53 6-19 1-08 0'80 577 9-38 1-08 1-58 0-70 99-92 100-31 A component with hornblende of the andesite, or diorite porphyry of the Cordilleras, and formerly considered an albite. No. 2 is an albite-like mineral (G. = 2'64) from Pisoje, near Popayan in Colum- bia, which is associated with hornblende and quartz. The proportion of silica is, however, still smaller than in andesin. 7. SACCHARITE, Glocker. Compact, or in fine granular masses, with traces of cleavage, at least in one direction. Very fragile ; fracture splintery, uneven ; H. = 5 6 ; G. =* 2*66 2-69. Translucent on the edges. Lustre vitreous, inclining to pearly or dull. Colour white, greenish -white, 126 LABRADORITE. [Felspar or apple-green. B. B. becomes greyish-white and opaque, but melts- only on thin edges. In borax forms a clear glass. Imperfectly so- luble in acids. Chem. com. exactly that of andesin, except the water, which is perhaps incidental. Analysis. Silica. Alu- mina. Iron per ox. Nickel oxide. Lime. Mag- nesia. Pot. ash. Soda. Water. Total. 58-93 23-50 1-27 0-39 5-67 0-56 0-05 7*42 2-21 100-0 Schmidt. Saccharite is found in veins in serpentine in the chrysoprase mines near Frankenstein in Silesia. 8. LABRADORITE, Beudant, Phillips; Labrador, Werner; Feldspath opalin, Hauy; Polychromatic felspar, Mohs. Triclinohedric, but dimensions unknown ; OP : ooPoo = 86 30' (or 85 32', according to Nordenskiold). Occurs in disseminated crystals, or massive and granular, forming polysynthetic macles like those of the pericline albite. Cleavage basal, very perfect, brachydiagonal less so ; and the planes of both usually striated ; H. = 6 . G = 2-68 2*74. Translucent, or only on the edges. Lustre vitreous, on the cleavage planes pearly or resinous. Colour grey, passing into white, green, yellow, or red. The faces of ooPoo often exhibit very beau- tiful changing colours, blue, green, yellow, red, or brown some- times in bands intersecting at certain angles. B. B. fuses more readily than orthoclase to a compact colourless glass. Soluble when pulverized in muriatic acid. Chem. com. i si.2 -I- RsS, consequently analogous to ryacolite, but with R chiefly (f) lime and Q) soda. Hence = 53'7 silica, 29'7 alumina, 12*1 lime, and 4-5 soda. Silica. Alu- mina. Iron perox. Lime. Mag- nesia. Soda. Pot- ash. Water. Total. 1 55-75 26-50 1-25 11-00 4-00 0-50 99-00 Klaproth. 2 54-67 27-89 0-31 10-60 0-18 5-05 0-49 99-19 Le Hunte. 3 52-34 29-97 0-87 12-10 3-97 0-30 ... 99-55 Do. 4 479 34-0 2-4 9-5 V 2 5-1 0-9 100 Laurent. 5 53-48 26-46 i-eo 9-49 174 4-10 0-22 0-42 a 98-40 Abich. 6 55-49 26-83 1-60 10-93 0-15 3-96 0-36 0-51 99-83 Segeth. 7 52-15 26-82 1-29 9-15 1-02 4-64 179 1-75; 9860 Svanberg. 8 52-52 30-03 1-72 12-58 0-19 4-51 101-55 Forchhammer. 9 52-30 29-00 1-95 11-69 0-15 4-01 : 50 ... 99^dO Kersten. 10 52-45 29-85 1-00 11-70 0-16 3-90 0-60 ... 99-66 Do. 11 52'20 29-05 0-80 12-10 0-13 w 98-98 Do. 12 54-13 29-23 15-46 ... 1 ; 07 99-88 Nordenskiold. 13 50-58 27-60 0-106 10-27 373 2 : 97 1-27 l-73c 99-12 Bergemann. 14 54.8 28-4 4-0 d 12-4 0-6 100-2 Thomson. (a) + 0'89 mang. prot. ; (b) iron prot. + 0'87 mang. perox. ; (c) loss by heat ; (d) protox. Nos 1-11, Labradorite, from (1) St Paul's island, Labrador; (2) greenstone porphyry, Campsie ; (3) Milngavie, near Glasgow ; (4) lava, Vesuvius (white) ; (5) lava, Etna (crys- tallized) ; (6) Kijew ; (7) hornblende rock, Tuna, Dalarne ; (8) dolerite porphyry, Faroe, G. = 2-67; (9) Egursund, Norway, brown, massive, G. -= 271 ; (10) do., with blue opal- escence, G. = 272 (11) do., violet- grey lively opalescence, G. 2-705. Family.] COUZEllAXITE. 127 Labradorite is a common constituent of many rocks, especially with augite, diallage, and hypersthene, as in dolerite greenstone, the gabbro, and hypersthene rocks. It also occurs in meteoric stones. The changing coloured variety is chiefly found in hypersthene rocks, as in Labrador and Finland. Bonsdorff ascribes this property to an excess of silica probably as quartz, and says these varieties contain 57 per cent, or more silica, the others only 52 ; but this is not confirmed by the analyses. Breithaupt says they differ in spec, gravity ; and Haidinger affirms that the play of colour proceeds from certain re- gularly-defined points. The Scolezerose, Beudant (anal. 12), or anhydrous scolezite from Pargas, Finnland, is a pure lime-labradorite. The Glaucolite (No. 13), from Lake Baikal, of a pale blue or greenish colour, with traces of cleavage in two directions, and G.= 272 2'9 (3'2, Fischer), does not seem distinct. Thomson's Silicite (No. 14) from Antrim is also perhaps a variety ; and from the white colour the iron is probably the peroxide (=4'5). Saussurifo, prismatic adiaphan-spar of Mohs, is a compact, dull, subtranslucent mineral, of a grey colour, inclining to blue, green, or red. H. = 6 ; G. = 2*69 3*4. B.B. fuses to a grey or greenish- white enamel, and is not acted on by acids. It seems merely an impure labradorite, occurring with, or in place of, this mineral in some gabbro and hypersthene rocks ; as in the Alps near Geneva, in the Harz, Styria, the Apennines, and in Corsica. Analyses. Silica. Alu- mina. Soda. Pot- ash. Lime. Mag- nesia. Iron perox. Total. 1 44-00 2 49-00 3 44-6 4 43-6 30-00 24-(10 30-4 32-0 6-00 5-50 7'5 0-25 1 : 6 4-00 10-50 15-5 21-0 ...a 3-75 2'5 2-4 12-50 6-50 96-80 99-25 100-5 100-6 T. Saussure. Klaproth. Boulanger. Do. (a) + 0-05 manganese perox. From (1) Lake of Geneva ; (2) do.; (3) Mont Genevre ; (4) Orezza valley, Corsica. With the so-called smaragdite it forms the Verde di Corsica duro, used for vases, &c., and for ornamenting the St Lorenzo chapel at Florence. 9. COUZERANITE, Charpentier : Monoclinohedric ; C = 87, ooP = 96. The usual combination is ooP . ooPoo . OP, with the surface vertically striated. Cleavage clinodiagonal ; fracture conchoidal or uneven. H. = 6 ; G. = 2'69. Opaque, vitreous, or resinous. Colour pitch-black, blackish-blue, or grey. B.B. melts to a white enamel ; with salt of phosphorus to a milk-white glass. Not affected by acids. Chem. com, 2 jjj s'i 2 4- 128 ANORTHITE. \Felspar 3 R si, or, by Dufrenoy's analysis, 52*37 silica, 24'02 alumina, (and 3 B = ) 11-85 lime, 1'40 magnesia, 5'52 potash, and 3'96 soda (= 98*55). It occurs imbedded in a limestone in les Couzerans in the Pyrenees. Von Kobell and Haidinger unite it with Labradorite. 10. ANORTHITE, G. Rose, Phillips, fyc. ; Biotina and Christianite, Monticelli; Anorthotomous Felspar, Mohs. Triclinohedric ; OP : ooPoo = 85 48' ; With lithia; (&) with manganese protoxide ; (c) + 1'5 manganese perox. ; (d) + 0'99 undecomposed matter ; (e) including also soda and potash. From (1) Tunaberg ; (2) Ersby, nearPargas, Finland, (Wernerite) ; (3, 4) Monte Somma, Meionite); (5) North America ; (6) Pargas (Ekebergite) ; (7, 8) Ersby (Wernerite;; (9) Petteby (do.); (10) Ersby (scapolite) ; (11) Bolton, Massachusets; (1219) mostly means of several trials; water = loss by heat ; (12) Malsjo, Wermeland, reddish or greenish-white, massive, G. = 2 '623 ; (13) Hirvesalo, Finland, blackish or greenish, crystals or compact. Ekebergite, G. = 2*733 ; (14) Bolton, Massachusets, reddish and whitish crystalline, Ek. G. = 2-718; (15) Hesselkulla, massive, greyish-green, Ek. G. =2-735; (16) Arendal, white or yellow, thin crystals of Ek. in limestone, G. = 2-?12 ; (17) Pargas, colourless crystals of sc. G.= 2-712; (18) Vesuvius, meionite ; (19) Sjosa, Sweden, red opaque crystals, G.= 2-643, probably metamorphosed; (20) Bocksaters, East-Gothland, massive sc. violet, G. 2-34. Nos. 12-17 were easily fusible. B.B. forming a white porous glass, and colouring the flame yellow. With salt of phosphorus they showed traces of fluorine, but not in the moist way. No. 19 was only fusible with much difficulty on the edges. Notwithstanding these numerous analyses, the constitution of this mineral is still uncertain, as they lead to no general formula. Rara- melsberg divides them into three classes. First, scapolite, = (c* a 8 , Na 3 )'si 2 + 2ii "si (or SB si + Ai 2 si 3 ) with 50 per cent, silica, and 4 7 soda, including Nos. 6, 8, 12-16, above. Second, Meionite c a 3 si,' + 2Jii sV, with about 42 per cent, silica and 1 3 soda and potash. Naumann proposes for this variety c'a 3 si 2 + 2 A! si with 40 sil., 3S al., and 27 lime, includes Nos. 3, 4, 18. This is the formula 138 NUTTALITE BARSOWITE. [Scapolite of the lime-epidote or zoisite, and the substance is consequently di- morphous. Third, Wernerite = c 'a 3 '" + 3A'i si (or c a si + A! si) with 44-45 per cent, silica, and 1^ alkali. To this belongs Nos. 1, 2, 17. This formula is also that of anorthite, and the substance is again dimorphous. In these compounds the oxygen of R XL and si have the proportions, 1:2:4, 1:2:3, and 1:3:4 respectively. The agreement of these compounds in crystalline form deserves fur- ther investigation, and also the proportion of fluorine they contain. Nos. 10, 11 are remarkable for the amount of water. The above are the principal localities of this remarkable mineral. It occurs chiefly in veins of magnetic iron, copper pyrites, or other ores, and in beds of granular limestone, and is most commonly associated with calc-spar, quartz, felspar, mica, augite, hornblende, and garnet. The fine transparent glassy variety, or meionite, is found in the ejected blocks on Vesuvius. The following five minerals are closely related to scapolite, if not mere impure or compact varieties. 18. NDTTALITE, Brooke. Tetragonal, P 64 40' ; forms and cleavage like scapolite. H. = 5'5 y G. = 2*74 2'75. Vitreous, on fracture resinous. Colour ash or greenish-grey. B.B. like scapolite. Chem. com. 2Xi si + 3ii 2 si. Analysis of specimen from Bolton, Massachusets. Sil. Al. Lime. { Soda. Potass. Iron protox. Water. Total Thomson. 37-81 25-10 18-34 | ... 7-31 7-89 | 1-50 | 97-95 19. BARSOWITE, G. Rose. In fine granular or compact masses, with a distinct cleavage, at least in one direction, H. = 5'5 6 ; G. = 2-74 2-76. Translu- cent on the edges ; lustre, pearly ; colour, snow-white ; B.B. melts with difficulty on the edges to a vesicular glass ; with salt of phospho- rus leaves a siliceous skeleton , with cobalt solution becomes blue. Gelatinizes in warm hydrochloric acid. 2(c'a, M g ,) si. Analyses. Chem. com. Al" Silica. Alumina. Lime. Magnesia. Total. 1 2 3 49-1)1 49-05 48-07 33-85 33 78 34-08 5'46 5-30 5-10 1-55 1-42 1-65 99-87 98-56 98-90 Varentrapp. Do. Do. Family.] OTTRELITE PALAGONITE . 139 It occurs in the auriferous sands of Barsowskoi in the Ural, and often includes crystals of corundum, pleonaste, and mica. The Bytownite of Thomson, from Bytown in Upper Canada, seems connected. It is crystalline with traces of cleavage, and a splintery fracture; H. = 6; G. = 2 -8. Translucent; lustre vitreous ; colour light greenish-blue. B.B. infusible but becomes white. Chem. com. (A'iiFe) s'i + (ca, Na, Mg) 2 si 3 , nearly corresponding with the mean of two analyses by Thomson, = 47*57 silica, 29'65 alumina, 3'57 iron peroxide, 9'06 lime, 7'60 soda, and 0'20 magnesia. 20. OTTRELITE, Hauy. Occurs in thin hexagonal tables, about a line broad, with a rather perfect cleavage parallel to the lateral faces. Scratches glass ; G.=4 - 4. Translucent ; vitreous ; and greenish or blackish-grey. B.B. melts difficultly on the edges to a black magnetic globule. Witlfborax, slowly fusible with reaction for iron ; with soda, strong reaction for manganese. Powder soluble only in warm sulphuric acid. Chem. com. i 2 si 3 + 3(pe, Mn) si +3k. Analyses. Silica. Alu- mina. Iron Mangan. protox. protox. Water. Total. 1 2 43-52 43-34 23-89 24-63 16-81 | 8-03 16-72 1 8-18 5-63 5-66 97-88 98-53 D amour. Do. Found in grey clayslate at Ottrez, near Stavelot, on the border of Luxemburg. 21. PALAGONITE, S. v. Waltershausen. Amorphous, fracture conchoidal, or uneven. Easily frangible. H. nearly 5 (Bunsen), rather more than calc-spar(S. v. W.) ; G. =2-4296. Transparent or translucent ; lustre resinous, inclining to vitreous ; colour wine-yellow to yellowish-brown ; sometimes coffee-brown in reflected, honey-yellow in transmitted light. When heated evolves water, and becomes dark-brown. B.B. fuses readily to a shining mag- netic bead. Easily soluble in hydrochloric acid, with separation of silica. Chem. com. (i 2 ' Pe 2 ) si 3 + 3 (c' a , Mg, Na) si + 9n. Analyses. 1 2 Silica: Alu- mina. 11-16 8-93 Iron pcrox. Lime. Mag- nesia. Soda. Pot- ah. w | Insoluble Water - | remains. Total. 37-42 32-91 14-17 12-87 8-77 7-55 6-04 4-24 0-65 1-28 0-68 0-99 1715 | 4-11 14-64 9-57 100-15 100-08 Bunsen. Do. () + 7'10 hygroscopic water- No. 1, from Seljadalr ; No. 2, from tufa Hekla. 140 DIPYR NEPHELINE. [Scapolite This mineral was discovered by Sartorius v. WaltershausBn in the tufa of Palagonia, in the Val di Noto, Sicily ; and more recently in that of Iceland, where it is very abundant. In composition it resem- bles ottrelite with thrice the water, or is a hydrous scapolite. 22. DIPYR, Hauy ; Schmelzstein, Werner. Tetragonal, in apparently regular, but rounded eight-sided prisms. Cleavage like scapolite. Scratches glass, G. = 2'646. Vitreous ; colour, whitish or reddish B.B. becomes opaque, and melts readily to a white vesicular glass. Slightly affected by acids. Chem. com. 3 A! si + 4 (ca, N) si 2 = 55-7 silica, 25-1 alumina, 91 lime, and 10-1 soda. Analysis from the mean of four. Silica. Alumina. Lime. Soda. Potash. Total. 1 55-5 24-8 9-6 9-4 07 100 Delesse. The dipyr occurs imbedded in slate or limestone at Mauleon, and in the valley of Castillon, in the Pyrenees. Its form has caused it to be joined to scapolite ; but Rammelsberg remarks the analysis brings it nearer to labradorite. 23. NEPHELINE, Hauy, Werner, Phillips ; Elseolite, Karsten ; Ehombohedral Elajin-spar, Mohs. Hexagonal; P 88 6', usual combinations, ooP . OP and ooP . OP . P. Crystals small, imbedded, or in druses ; also massive and large granular ; cleavage basal, and prismatic along ooP, imperfect. Frac- ture conchoidal or uneven ; H. = 5'5 6 ; G. = 2'58 2-64. Trans- parent or translucent, lustre vitreous, colourless, or white (Nepheline); or more opaque, dull resinous lustre, and green, red, or brown colours, (El&oliteO B.B. melts difficultly (nepheline), or easily with slight effervescence (elasolite) into a vesicular glass. Soluble in borax, and with difficulty in salt of phosphorus. Becomes blue with solution of cobalt. Wholly dissolved and gelatinizes in hydrochloric acid. Chem. com. jgLi 5 si 6 + 4 N a si + k si. Analyses. Si- |Alu- Soda Pot- | Mag- Iron lica. |mina ash. Jim j nesia - perox Watr. Total. 1 44-1 113373 2 44-12 133-46 3 4370 32-31 4 43-36 133-49 20-46 15-43 15-83 13-36 473 5-60 7-13 1-87 0-84 0-90 trace o'-49 1-07 1-50 0-62 0.21 1-39 1-39 98-92 100-31 100-74 101-13 Arfvedson, Somma. Scheerer, Do. M. of 3. Scheerer, Odenwald. L. Gmelin, do. 5 45-23 i32-66 6 45-55132-00 15-72 16-09 5-66 5-02 0-33 trace ... 0-56 1-41 0-62 0'78 100-78 100-85 Scheerer, Fredriksvarn. Do do 7 44-53J32-08 8 44-07 33-12 9 41-42i34-06 15-72 15.70 15-13 5-17 5-69 6-43 0-26 0-26 0-34 trace 0-61 1-08 0-57 trace 2-06 090 0-46 100-90 100-31 99-41 Do. Brevig. Scheerer, Miask. Bromeis, Do. Family.] DAVYNE. 141 Nos. 1-4 are the nepheline or more transparent crystalline varieties. No. I, remarkable as showing no potash, and No. 2 a mean of three trials, are from ejected blocks on Monte Somma, where it is associated with meionite, &c. It also occurs in the leucite-lava at Capo di Bove and other places near Rome ; and in the dolerite of the Katzen- buckel in the Odenwald (Nos. 3, 4), at Aussig Bohemia, and in the Lausitz. The elasolite (Nos. 5-9) occurs in the zircon syenite of Southern Norway at Laurvig, Fredriksvarn (No. 5, green, mean of 2; No. 6, brown var.), and Brevig, (No. 7, brown, mean of 2). It is a constituent of the miascite of the Ilmen Mountains near Miask (No. 8, mean of 2, and No. 9, both white). In this variety Bromeis found O04 per cent, hydrochloric acid, and Scheerer - 06 per cent, of this, with 0'07 per cent, sulphuric acid. The latter found O22, and in a purer variety 0*05 hydrochloric acid, with traces of sulphuric acid in nepheline from Vesuvius. The Cavolinite and the Beudantite of Monticelli and Covelli seem only nepheline. Beudant considers the Indianite as a lime-nepheline, but it seems nearer anorthite. 24. DAVYNE, Monticelli and Covelli; Cancrinite, G. R$se ; tomous Elaein-spar, Mbhs. Hexagonal; P 51 46', usual combinations ooP . OP, aa (V) 126 40'; most common combinations, OP . o>P, or also with ooPoo ; and ocP (m) . OP (P) . ccPoo (/) . 3Poo (0), fig. 112. The crystals are tabular or short pris- matic, combined in druses, in fan-shaped or cock's-comb groups. Also found granular, and in spherical, reniform masses, with a laminar or fibrous structure. Cleavage basal, rather perfect, prismatic along ooP imperfect. H. = 6 7 ; G. = 2'8 3. Semitransparent or translucent on the edges. Lustre, vitreous, on OP pearly. Colour- less, but mostly coloured greenish-white, olive, apple, or leek-green. Streak, white. When heated becomes polar-electric. In the closed tube yields water without losing its transparency. B.B. melts easily, and with much intumescence to a porous enamel. Soluble in concentrated hy- drochloric acid, but only gelatinizes perfectly when Fig. 1 p 12. (T p M i M to \~, 144 PREHNITE. \_Scapolite previously ignited or fused. Chem. com. 2c a si + L& + H = 44-4 silica, 24'6 alumina, 26'7 lime, and 4'3 water. Analyses. Silica. Alu- Lime. Iron Mang. Watr. Total. mina. perox perox. 1 43-00 23-25 26-00 2-00 0-25 4-OOa 98-50 Gehlen, Ratsohinges. 2 42-88 21-50 2650 300 0-25 4-63 98-76 Do. Fassa. 3 43-03 19-30 26-28 6-81 0-15 4-43 100-20 Walmstedt, Aedelforss. 4 44-7] 23-99 25-41 1-256 0-19 4 '45 100 Do. Mont Blanc. 6 44-10 24-26 26-43 074& ... 4-18 9971 Do. Dumbarton. 6 43-60 23-00 22-33 2-00 6'40 97-33 Thomson, Glasgow. 7 44-74 18-06 27-06 7-38 l-03c 4-13 102-40 Amelung, Radauthal. 8 42-50 30-50 22-57 0-04 0-02d 5-00 100-63 G. Leonhard, Niederkirchen. 44-00 28-50 22-29 0-04 0-Old 6-00 10084 Do. do. (a) Traces of soda and potash; (6) iron-protoxide; (c) soda; (d) potash. Occurs in various rocks, as granite, euphotide, and greenstone, some- times disseminated, but more commonly in fissures, veins, and druses. It was first found at the Cape of Good Hope in 1779. Very fine crystals occur at Bourg d'Oisans in Dauphine, and Ratschinges, near Sterzing in Tyrol. Common in the Alps, Pyrenees, Harz (No. 7 in Euphotide), and Norway. In Scotland it is found in trap at Friskie Hall, and Camp- sie, Dumbartonshire (white and opaque) ; Hartiield Moss, Renfrew- shire ; Corstorphine Hill, the Castle Rock (translucent and colourless), and Salisbury Craigs (yellow), near Edinburgh. No. 3 is the so-called sedelite, and No. 4 the koupholite. No. 8 is a pseudomorph in the form of analcim, and No. 9 in that of leonhardite. According to Reiss and Rose, the pyro-electricity has central polarity ; the analogue pole being in the middle of the shorter diagonal of the basis, and two antilogue poles at its extremities, and consequently the acute edges of the prism are non-electric. 28. The following minerals, whose true place in the .system is still uncertain, may follow prehnite. (a.) Zeuxite of Thomson : found in Huel Unity Mine, near Redruth, Cornwall, in acicular crystals, apparently rectangular prisms, collected in fibrous masses, H. = 4 5 ; G. = 3'0 3'1 ; Opaque ; lustre, vitreous ; greenish brown. B.B. infusible alone ; with borax forms a dark-brown glass. Analysis No. 1, which gives nearly 3jj[j si + 2k 2 si + 3ii, when R = |pe + c a . (&.) Kirwanite of Thomson : found in basalt in the Mourne Mountains, Ireland, in spheroidal masses, with a radiating fibrous texture, H.*= 2 ; G. = 2-9. Opaque ; dark olive-green. B.B. becomes black, and partially fuses. With soda or borax forms a dark-brown glass. Chem. com. 3c a si + 3pe si + H 2 A!- Analysis No. 2. (c.) Huroniteof Thomson : in rounded granular or foliated masses, in loose blocks on Lake Huron, North America, H.=3'25 ; G.=2'86. Family, ,] NEPHRITE. 145 Translucent; pearly or resinous lustre ; colour pale yellowish-green,- streak greyish-white. B.B. infusible, but becomes greyish-white; with borax forms a greenish glass, Not affected by acids. Chem. com. 2ii 2 si 3 + 3(ca, Fe, Mg) si + 3 H . Analysis No. 3. (rf.) Neurolite, Thomson, from Stamstead in Lower Canada, is massive and fine columnar, H. = 4-25 ; G. = 2-47 ; translucent or opaque ; colour greenish-yellow. B.B. infusible, but becomes snow- white and pulverulent ; with soda forms a transparent glass. Chem. com. 2^1 si 6 + ca si 2 + 3n. Analysis No. 4. (e.) Onkosin, v. Kobell, from dolomite, near Lungau in Salzburg, massive, fracture uneven, or splintery ; sectile ; H. = 2 ; G. = 2'8 ; Translucent ; slightly resinous lustre ; colour apple-green, greyish or brownish, B.B. intumesces and fuses to a white porous glass. Perfectly soluble in sulphuric, but not in hydrochloric acid. Chem. com. nearly 3^1 si 2 + (K, Mg) 2 si 3 + SH> Analysis No. 5. Silica. Alu- mina. Iron protox. Lime. Mag- nesia. Pot- ash. Watr. Total. 1 2 3 4 5 33-48 40-50 45-80 73-00 52-52 31-85 11-41 33-92 17-35 30-88 26-01 23-91 4-32 0'40a 0-80 2-46 19-78 8-04 3-26 172 1-50 3-82 6 : 38 5-28 4-35 4-16 4-30 4-60 99-08 99-95 97-96 99-80 99-00 Thomson. Do. Do. Do. v. Kobell. (a) Peroxide. 29. NEPHRITE, Werner, Phillips, fyc. ; Jade, Hauy ; Uncleavable Adiaphane-spar, Mohs. Only known in compact masses with a coarse splintery fracture. Very tenacious ; H. = 6 6'5 ; G. = 2*9 3. Translucent. Lustre dull or resinous. Colour leek-green to greenish-white or blackish- green. Feels slightly greasy. B.B. some become white and melt with difficulty to a grey mass ; others (as Nos. 5, 6,) intumesce and melt slowly to a white enamel. Analyses. Silica. Mag- nesia. Lime. Iron. Man- ganese. Alu- mina. Pot- ash. Watr. Total. 1 2 3 4 54-68 58-91 58-88 58*46 26-01 22-42 22-39 27 -09 16-06 12-28 12-15 12-06 2-1 5a 2-706 2-816 l-15a i-aoa 0-916 0-836 1-32 1-56 : 80 0-80 0-68 0-25 0-27 100-97 99-59 99-69 98'76 Rammelsberg. Schafhautl. Do. Damour. 5 6 7 58-02 50-50 41-69 27-19 31-00 34-63 11-82 4-25 M2a 5-506 1-756 0-05c KH"O 0-56 ::: 275 13-42 98-15 99-80 96-30 Do. Kastner. Bowen. (a) Protoxide; (6) peroxide; (c) chrome oxide. No. 1 from Turkey was determined as nephrite by Breithaupt ; No. 2 was cut into an amulet ; No. 3 into a ringstone, both from the east, G. = 2-96 ; Nos. 4, 5 were milk-white oriental jade ; G. = 2'97. N 146 LAZULITE. [Haloid Stones These analyses give rather discordant results. No. 1 resembles augite, whereas Nos. 2-5 are exactly the composition of white tre- molite. It is thus probable that nephrite is merely a peculiar condi- tion of augite and hornblende. It comes chiefly in a manufactured state from Turkey and the east. In China it is much valued for its supposed medical properties, and is cut into various ornaments and amulets. It was also used by the ancient Egyptians ; and the natives of New Zealand fashion a similar stone, the Poenamu, into axes and other weapons. No. 6, an old analysis, is a wholly distinct mineral. No. 7, from the primary limestone, of Smithfield Rhode Island, is of a fine sky-blue colour, and, if pure, also distinct. IV. FAMILY. HALOID STONES. 30. LAZULITE, Karsten, Werner, Hauy, fyc. ; Azurite, Phillips; Klaprothine, Beudant, Dufrenoy ; Blauspath, Werner ; Pris- matic Azure-spar, (Lazurspath), Mohs and Jameson. Rhombic ; ooP 91 30', Poo 59 20', Poo 58 30', The crystals, formed predominately by the acute pyramid P and the above three prisms, somewhat resemble those of sulphur, but are extremely rare. Usually it occurs massive or disseminated in distinct granular aggre- gates. Cleavage, probably prismatic along ooP, imperfect ; fracture uneven, splintery ; H. = 5 6; G. = 3 3*1. Translucent on the edges ; lustre vitreous ; colourless, but almost constantly coloured indigo, smalt, or other shades of blue inclining to green or white. Streak white. In closed tube yields water and loses its colour. B.B. intumescesj but does not melt. With cobalt solution assumes a fine blue colour. Colours the flame slightly green. Scarcely affected by acids till after ignition, when almost wholly soluble. Chem. com. according to Rammelsberg, [2(Mg, FC ) 3 "" + jii 4/ p'' 3 ] + 6 ii or a hydrous combination of a phosphate of alumina and a phosphate of magnesia and protoxide of iron. Analyses. Phospho- ric acid. Alu- mina. Mag- nesia . Iron protox. Lime. Water. Total. 1 41-81 35-73 9-34 2-64 6-06a 97-68 Fuchs. 2 42-41 29'58 10-67 1060 1-12 5-62 100 Rammelsberg. 3 43-84 33-09 9-00 6-69 1-44 5-94 100 Do. 4 46-99 27-62 11-19 6-47 2-12 5-61 100 Do. 5 41-33 32-68 9-54 954 0-77 6-14 100 Do. 6 47-04 26-92 10-67 7-84 1-21 6-32 100 Do. 7 40-95 36-22 12-85 1-64 1-42 6-92 100 Do. 8 47-36 30-05 12-20 1-89 1-65 6-85 100 Do. 9 47-73 27-48 12-16 1-91 4-32 6-40 100 Do. (a) + 2-10 Silica. l,from Radelgraben, Salzburg $ 2-6, dark-blue lazuli te from the Fischbacher Alp, near Gratz, Styria,G. = 3-11 ; 7-9, light-coloured blue spar from Fressnitzgraben, near Krieglach n Styria, G. = 3-02. Family.] CALAITE. 147 In Rammelsberg's analyses the silica considered as a mixture is first abstracted. It amounted to 0-53 in No. 1, 4-44 in No. 2, 6 -64 in No. 8, and 12-56 per cent in No. 9. R. remarks that in the first mem- ber of the formula the phosphoric acid is in the same state of satura- tion as in the wagnerite and vivianite, whilst the second represents the chief constituent of the wavellite. The lazulite occurs in small veins with quarz and carbonate of iron, in clayslate in the torrent beds of the Schlamming and Radelgraben near Werfen in Salzburg. Also it is said at Waldbach near Vorau in Styria, whence named the Voraulite. The blue spar is found in large blocks, or rarely indistinct crystals with quarz and mica, near Krieg- lach in Upper Styria, and at the foot of the Wechsel, near Theren- berg, in Lower Austria. Also crystallized and massive at Tijuco in Minas Geraes, Brazil. 31. CALAITE, von Waldheim t Phillips^ 8fc. ; Callais, Pliny; Mine- ral Turquois, Jameson ; Tiirkis, von Leonhard ; Uncleavable Azure-spar, Mohs. Amorphous, reniform, stalactitic, or encrusting. Fracture con- choidal or uneven, H. = 6 ; G. = 2-62 2'8. Opaque or feebly translucent on the edges ; lustre dull or waxy ; colour skye-blue, greenish-blue, rarely pistachio or apple-green ; streak greenish-white. In the closed tube yields water, decrepitates violently, and becomes black. B.B. infusible, but colours the flame green 5 with borax and salt of phosphorus, shows reaction for copper and iron. Soluble in acids Chem. com. Ai 2 p* + 5 H =46*89 alumina, 3257 phosphoric acid* and 20'54 water, but mixed with a little phosphate of iron and cop- per. Analyses. 1 2 3 4 Phospho- ric acid. 30-90 38-90 27-34 5-64 Alu- mina. Watr. Copper protox Iron >erox. Mangan perox. Phosphate of Lime. Total. 44-50 54-50 47-45 50-75 19-00 1-00 18-18 18-13 3-75 1-50 2-02 1-42 1-80 2-80 MO 1-10 : 50 0-60 3-41 18-106 99-95 98-70 100 100 John. Zellner. Hermann Do. 5 29-63 38-47 27-50 0-80 1-20 3-OOc 100 Do. 6 30-49 44-49 22-82 2-20c ... 100 Do. (a) Protoxide ; (6) + 4-26 silica ; (c) with veinstone. The composition of this mineral seems far from uniform ; but the above formula corresponds with No. 1, and, though less exactly, with 3 and 6. In No. 2 the proportion of phosphoric acid to alumina is nearly the same, so that it is perhaps the anhydrous mineral The green variety, No. 4, seems a very uncertain mixture. 4 148 WAVELLITE. [Haloid Stones It occurs in fissures in flinty slate at Jordansmiihle in Silesia (Nos. 1 and 2), in the Lausitz, and in the Voigtland, and in clayslate, near Striegau. The Oriental turquoise, No. 3, azure blue, G. = 2'621, and No. 4, green, is said to occur in veins, but chiefly in pebbles in allu- vium in Persia, as at Nichabur in Khorazan, and in Bucharia; and recently also in the Syrian desert. It takes a fine polish, and is valued as an ornamental stone ; the King of Persia, it is said, retaining the finer specimens for his own use. Some fossil teeth and bones, coloured by hydrated copper- oxide, or phosphate of iron, from Miask in Siberia and Trevaux in France, are often substituted for this mineral. The Fischerite of Hermann (No. 5 of anal.) is a green mineral from Nischnei Tagilsk, where it occurs in crystalline crusts or small indis- tinct six-sided prisms, H. = 5 ; G. = 2-46. It is only slightly solu- ble in muriatic or nitric, but wholly in sulphuric acid : and on heating becomes white or partly black. It seems ^i 2 "+ 8k, or (i 4 '' 8 + I&H) + 2i H 3 that is, a combination of wavellite (with no fluorine) and of gibbsite. The Peganite of Breithaupt (No. 6), from Strigis in Saxony, usually classed with wavellite, agrees with the above in chemical character, its composition being i 2 '$' + 6n. It is probably rhombic ( ocP 127^ nearly), and occurs in very small prismatic crystals, formed by coP . OP . ooPoo . These are united in thin crusts, of an emerald, grass- green, or white colour, H.= 3 4 ; G.= 2-49 2'54. As Ram- melsberg observes, calaite, fischerite, and peganite are thus various hydrates of one and the same phosphate of alumina. The Varisdte of Breithaupt, forming a green reniform incrustation, with weak resinous lustre and greasy feel, on flinty slate at Messbach, near Plauen, in the Voigtland, seems a similar compound. In the closed tube it yields much water, and assumes a rose-red colour. B.B. in the forceps colours the exterior flame intense bluish-green, becomes white, but is infusible ; with borax forms a yellowish-green glass ; with cobalt solution becomes blue. Plattner considers it as chiefly composed of alumina and phosphoric acid, with water, ammonia, magnesia, protoxide of iron, and chrome-oxide. (32.) WAVELLITE, Jameson, Werner, Phillips; Lasionite, Fuclis; Devonite, Thomson ; Alumine Phosphatee, Hauy ; Prismatic Wavelline Haloid, Mohs. Rhombic (microcrystalline), ooP 126 25', PGO 106 46', usual com- bination ooPoo (P) . ccP(d) . Poo (o)fig. 113 ; but the crystals generally small, acicular, and united in minute hemispherical masses, with a Family.'] WAVELLITE. 149 radiated fibrous texture and drusy surface. Cleavage, along ooP and Fig. 113. poo rather perfect, H.= 3'5 4 ; G. = 2-3 2'5. Trans- lucent ; vitreous lustre ; colourless, but generally yellowish or greyish, sometimes a beautiful green or blue In closed tube yields water, often with traces of fluoric acid. B.B. in the forceps colours the flame weak bluish-green; on char- coal intumesces, and becomes snow-white; with cobalt so- lution blue. Soluble in acids, and in warm sulphuric acid often with evolution of fluoric acid. Chem. com. essentially i 3 *' 2 + 12k with 38-0 alumina, 35-3 phosphoric acid, and 267 water ; but Berze- lius proposes AI ri 3 + 3( AI* *ip* 3 + 18k). Analyses. Alu- mina. Phospho ric acid. Water. Fluoric acid. Iron perox. Lime. Silica. Total. 1 37-18 34-98 28-00 ... ... 100-16 Fuchs (M. of 2) 2 35-35 33-40 26-80 2-06 1-250 : 50 99-36 Berzelius. 3 36 -60 34-06 27-40 traces 1.00 ... 99-06 Erdmann. 4 36-39 33-28 27-10 traces 2-69 ... ... 99-46 Do. 5 34-90 31-55 24-01 traces 2-21 7-30 99-97 Do. 6 35-39 32-46 24-00 traces 1-50 6-65 100-00 Do. 7 10-01 17-86 25-95 36-32 0-15 8-90 99-19 Steinman. 8 11-29 9-20 18-98 36-83 M 3306 99-70 Holger. 9 20-5 30-2 43-1 1-1 2-lc 97-9 Richardson. 10 36-39 34-29 26-34 l-69cZ 1-20 - ... 99-91 Hermann. (a) With peroxide of manganese ; (6) +7'58 magnesia, 1-23 zinc-oxide, and 11-29 sulphuric acid; (c) + 0-9 magnesia ; (d) fluorine. From (1, 2) Barnstaple, Devonshire; (3, blue, 4, green and yellow, 5, brown, 6, black, varieties) Langen Striegis, near Freiberg ; (7, 8, 9> 10) Zbirow, near Beraun, in Bohemia. This mineral, named from Dr Wavel, its discoverer, occurs in small veins and fissures, sometimes in clayslate and other older rocks, as in various places near Beraun in Bohemia ; at Frankenberg and Langen Striegis, Saxony, Tanne in the Harz, Barnstaple in Devonshire, near Clonmell and Cork, Ireland, and in the Shiant Isles in Scotland ; in granite at Stenna Gwyn, near St Austle, Cornwall, and Roxborough in Pennsylvania ; in secondary formations, at Amberg in Bavaria, and near Newcastle in England. Also near Saxton's River, New Hamp- shire, and Nashville, Tennessee in North America. The so-called wa- vellite from Villa Ricca is shown by von Kobell to be Hydrargillite. This chemist states, that the surest method to distinguish the phosphates from the hydrates of alumina, is to add acetic acid to the solution in muriatic acid, till ammonia produces no precipitate ; if sulphate of magnesia and sal-ammoniac be now added, wavellite and other phos- phates of alumina give a precipitate, the hydrates of alumina none. Kakoxene (analyses 7, 8, 9) is by some regarded as a distinct mi- neral, and (Nos. 7 and 9) when the alumina and silica are abstracted. 150 WAGNERITE AMBLYGONITE. [Haloid Stones as mixtures, give nearly the formula jv 2 + 12ri. No. 10 of the mineral from the same locality corresponds, however, with wavellite, and the others are evidently from impure specimens. 33. WAGNERITE, Fucks, Phillips; Fluophosphate of Magnesia, Thomson; Magnesie phosphate^, Dufrenoy ; Hemiprismatic Dysthom-spar, Mohs. MonocUnohedric, C = 63 25', o>P 57 35', Poo 71 53'. The crystals form very complex combinations, and appear like short prisms with vertical striae. Cleavage prismatic along ooP, and orthodia- gonal imperfect, also traces along OP. Fracture conchoidal or splin- tery; H. = 5 5*5; G. = 2*985 opaque, 3'068 transparent crystals (Rammelsberg). Translucent or transparent ; lustre resinous, in- clining to vitreous ; colour wine-yellow, honey-yellow, and white. B.B. fuses with great difficulty in thin splinters to a dark-greenish grey glass. Moistened with sulphuric acid, colours the flame weak bluish-green. Powder slowly soluble, with escape of fluoric acid, in warm nitric and sulphuric acids. Chem. com. Mg 3 P' + Mg Fl with 43'32 phosphoric acid, 11*35 fluorine, and 37*64 magnesia, and 7 '69 magnesium. In analysis 50 f 38 magnesia will be found. Analyses. 1 2 3 4 Mag- nesia. Iron perox. Manga, perox. Phospho- ric acid. Fluoric acid. Lime. Silica. Total. 46-66 45-07 46.27 1-49 5-00 4-4?a 4-59a l-41c 0-50 41-73 39-56 40-61 1-87 6-50 9-126 9-366 2-32 2-38 2-58 2 : 68 93-81 100-39 103-22 103-22 101-16 Fuchs. Rammelsberg. Do. Do. (a) Protoxide; (6) fluorine; (c) alumina and iron peroxide. This mineral is very rare, having only been found in irregular veins with quarz in clayslate in the Hollgraben, near Werfen in Salzburg. No. 2 is the original analysis, No. 3 the same after rejecting the silica arising from incidental mixture, to which some other elements should also be ascribed. No. 4 is a soft reddish mineral found with it, and probably wagnerite, decomposed and replaced by silica. 34. AMBLYGONITE, Breithaupt, Phillips, $$c. ; Prismatic Amblygon- spar, Mohs. Rhombic ; in coarse granular masses. Cleavage prismatic along ooP 106 10' tolerably perfect ; brachydiagonal imperfect. Fracture uneven and splintery ; H. = 6 ; G. = 3 3*1. Translucent, lustre vitreous, pearly on ooP, on fracture surfaces inclining to resinous. Colour greyish or greenish-white, to pale mountain-green. In closed tube yields water sometimes corroding the glass. B.B. fuses very Family-.'] ALUNITE. 151 readily to a transparent glass, becoming opaque when cold. Colours the flame rather yellow than red ; but moistened with sulphuric acid bluish-green. Finely pulverized it is soluble slowly in hydrochloric acid, more readily in sulphuric acid. Chem. com. according to Rammels- berg,(Al 5 'p' 3 + R 5 sodium. Analyses. + (A1F 3 + RF; in which R is lithium and 1 2 3 4 Phospho- ric acid. Alu- mina. Lithia Soda. Potash. Fluo- rine. Alumi- nium. Li- thium Sodium. Total. 48-00 47-15 48-00 47-87 36-26 38-43 30-69 34-46 6-33 7-03 5-21 6-90 548 3-29 4-51 5-98 Undet. 0-43 8-il 8-36 2-97 : 50 072 100-71 103-57 These analyses by Rammelsberg are (1, 2) actual results, the fluo- rine being found by another trial. No. 3 is No. 1 according to his interpretation of its composition ; and No. 4 is the amount which by the formula analysis should give. This mineral is found in veins in granite at Chursdorf and Arnsdorf near Penig in Saxony, with turmaline, topaz, and other minerals. Also, it is said, at Arendal in Norway, with garnet and augite. 35. ALUNITE, Cordier, Dufrenoy ; Alumstone, Phillips, fyc. ; Alauu- stein, Werner ; Rhombohedral Alum Haloid, Mohs. Rhombohedric ; R 92 50' ; the crystals are almost constantly Fig. 114. either R, or R . OR (fig. 114) ; they are small, often with curved faces, and combined in groups or druses. It very frequently occurs in minute or fine granular, earthy or compact mass- es, intimately mixed with quartz or felspar. Cleavage basal, rather per- fect. H. = 3-5 4; G. = 2-6 2-8. Translucent; lustre vitreous, on OR pearly. Colourless and white, but coloured greyish, yellowish, or reddish. B.B. infusible alone. With borax forms a colourless glass. Becomes blue with cobalt solution. Soluble in warm concentrated sulphuric acid : not affected by hydrochloric acid. Water extracts alum from the ignited mineral. Analyses. Sulphu- ric acid'. Alu- mina. Potash. Water. Silica. Iron per ox. Total. 1 12-50 2 27-00 3 35-6 17-50 31-80 40-0 1-00 580 13-8 5-00 3-72 10-6 62-25 28-40 1-44 98-25 98-16 100 Klaproth, Hungary. Cordier, Mont Dore. Descotils, Montione. 4 35-5i) 39-65 10-02 14-83 100 Cordier, Tolfa. 5 27-0 26-0 7-3 8-2 26-5 4-0 99-0 Berthier, Hungary. 6 39-42 37-95 10-66 11-97 100 Do. Do. 152 ALUMDttTE. [Haloid Stones The compact varieties (1, 2) are evidently mixtures, and can furnish no formula. Nos. 5 and 6 are the same analysis, the- latter with the impurities abstracted. It gives nearly 3 AI *s' + k's" + 6 H, whilst that of Cordier, No. 2, agrees better with AI* 's 3 + k's* + 8 H. Alunite is found massive in Hungary, at Beregszasz (Nos. 1, 5), and Muzay ; and at Tolfa near Civita Vecchia in the Papal States, in distinct crystals. It also occurs in Tuscany, near Naples, in the crater of Volcano, one of the Lipari islands, in loose blocks in Auvergne, and in the Greek islands of Milo and Argentiera. The Konian alum, valued on account of its purity, is chiefly obtained from this mineral by repeated roasting and lixiviation. Berthier ex- plains the singular change produced in this substance by ignition from an alteration in the grouping of the atoms. In volcanic regions it is often formed by the action of sulphurous vapours on trachyte, and in other felspar rocks, by the decomposition of iron pyrites. 36. ALUMINITE, Jameson, Mohs ; Subsulphate of alumina, Phillips ; Websterite, Levy, Dufrenoy. Cryptocrystalline ; only in reniform masses, with a very fine scaly or fibrous structure. Fracture earthy ; sectile or friable ; H. = 1 ; G = 1*7. Opaque ; lustre dull or glimmering ;, colour snow-white or yellowish-white. In closed tube yields much water. B.B. on ignition emits sulphurous fumes, the remainder being infusible, and acting like alumina. Easily soluble in hydrochloric acid. Chem. com. of purest varieties, jjj s* + 9 H, with 29' 8 alumina, 23'2 sul- phuric acid, and 47 water. Analyses. Alu- mina. Sulphu- ric acid. Water. Total. 1 29-87 23-37 4676 100 Stromeyer, Newhaven. 2 30-26 23-37 46-37 100 Do. Halle. 3 30-98 23-68 45-34 100 Do. Mori. 4 29-23 23-25 46 -34 a 100 Schmid, Halle. 5 30-7 22-3 47-0 100 Marchand, do. 6 29-72 23-45 46-80 99-97 Dufrenoy, Lunel Vieil. 7 30 23 47 100 Dumas, Auteuil. 8 39-50 11-45 48-80 99-75 Marchand, near Halle. 9 36-0 17-0 47-2 100-2 Do. do. 10 36-17 14-54 49-03 99-74 Schmid, do. (a) + 1-18 lime. This mineral seems of recent origin, from the decomposition of the clay in which it is found, as at Newhaven in Sussex, Epernay, Auteuil, and Lunel Vieil in France ; at Halle and Mori in Prussia. Nos. 8, 9, 10, are analyses of a substance found south from Halle, of a similar cha- racter, and probably aluminite mixed with a hydrate of alumina ; or, Family.] PISSOPHANE LATROBITE. 153 No. 8, = 2 aluminite + 3 jjj H G ; No. 9, = 3 aluminite + and No. 10, = 1 aluminite + i H 6 . H, H ; 37. PISSOPHAJSE, Breithaupt. Stalactitic and massive ; fracture conchoidal ; rather sectile, and very easily frangible. H = 2; G = 1-92 1-98. Transparent or translucent ; lustre vitreous. Colour olive-green to liver-brown ; streak greenish-white to pale yellow. B.B. becomes black, and with fluxes shows reaction for iron. Easily soluble in hydrochloric acid. Analyses. j Sulphu- ric acid. Alu- mina. Iron perox. Water. Veinstone and Loss. Total. 1 1 1270 2 12-49 3 11-90 35-15 3530 6-80 974 980 40-06 41-69 41-70 40-13 0-72 0-71 Ml 100 100 100 Erdmann, green var. Do. do. Do. yellow sta lac Nos. 1, 2 give R S *s 2 + 30 H ; whereas R 2 's + 15 H, agrees bet- ter with No. 3. It is probably a mixture of several salts formed from the decomposition of alumslate, in which it occurs at Garnsdorff near Saalfeld (anal. 1-3), and at Reichenbach in Saxony. It is still forming, exuding in syrup -like drops, which gradually harden to a horny consistence. 38. LATROBITE, Brooke ; Diploite, Breithaupt. Triclinohedric ; in indistinct prismatic crystals ; but mostly mas- sive and disseminated. Cleavage in three directions, intersecting at 91, 93 30', and 98 30'. Fracture uneven. H. = 5 6 ; G. = 2'7 2*8. Translucent ; vitreous ; colour peach-blossom or rose-red, and reddish-white. B.B. becomes white, intumesces, and melts on the edges to a porous mass. With soda on platinum wire shows traces of manganese. In borax melts to a clear glass. Chem. com. per- 4 AlSi + 2 ca Si + KSi. Silica. Alu- mina. Lime. Pot- ash. Mang. Mag- perox nesia. Watr. Total. 1 44-65 36-81 8-28 6-68 3-16 1 0-63 2-04 102-16 C- G. Gmelin. 2 41-78 32-83 9-79 6'58 6-77 2*04 98-79 Do. Found with felspar, mica, and calc-spar at Amitok island (No. 1, 2) in Labrador, and also, it is said, at Bolton, Massachusetts. Breithaupt joins the amphodelite to this species, but it is rather a variety of anorthite. 154 PROCELAIN SPAR. \Leucite V. FAMILX-. LEUCITE. 39. LEUCITE, Werner, Phillips ; Amphigene, Hauy ; Trapezoidal Ampliigene-spar, MoJis. Tesseral ; only 2O2 (fig. 6 above) yet observed. The crystals are generally single, and with all their faces formed; more rarely in groups or granular aggregates. Cleavage hexahedral, but very imper- fect. Fracture conchoidal. H. = 5'5 6 ; G. = 2-4 2-5. Trans- parent to translucent only on the edges. Lustre vitreous, inclining to resinous. Colourless, but coloured greyish, yellowish, or reddish- white, or grey ; streak white. B.B. infusible alone ; with borax dif- ficultly to a clear glass ; with cobalt solution becomes blue. Soluble in hydrochloric acid without gelatinizing. Chem. com. jiisi 3 + KS'I, with 55.7 silica, 23'1 alumina, and 21'2 potash. Analyses. Silica. Alu- mina. Pot- ash. Soda. Iron perox. Lime. Total. 1 2 3 4 53-75 54-50 56-10 56-05 24-63 23-50 23-10 23-03 21-35 19-50 21-15 20-40 i"o2 6 : 95 trace. 99-73 97-50 101*30 100-50 Klaproth, Vesuvius. Do. Pompeii. Arfvedson, Vesuvius. Awdejew, Somma. This mineral is remarkable as the one in which Klaproth first dis- covered that potash was a constituent of the mineral kingdom. Ac- cording to Sir D. Brewster, it possesses two axes of double refrac- tion, and is consequently one of the few exceptions to the optical laws prevailing in the system of crystallization to which it belongs. It is frequently associated with augite, and is abundant in the lavas of Vesuvius, the tufas near Rome, and the peperino of Albano. At Rieden, near Lake Laach on the Rhine, it occurs in a crystalline mix- ture with glassy felspar, nosean, augite, &c. The larger crystals (as in the lava of Borghetta) often enclose portions of lava or small crys- tals of augite, which shows, according to v. Buch, that the leucite has been formed from the lava during its cooling. 40. PROCELAIN SPAR, Fuchs, Molis. Rhombic ; o>P 92 nearly. Occurs massive and distinctly coarse granular. Cleavage brachydiagonal, rather perfect, alsomacrodiagonal. Fracture uneven. H. = 5'5 ; G, = 2-67 2-68. Translucent, or only on the edges. Lustre vitreous, or pearly on the cleavage planes. Colour yellowish or bluish-white, or pale grey. B.B. fuses easily with intumescence to a colourless vesicular glass. Soluble without gelatinizing in concentrated hydrochloric acid. Analyses. Family.'] SODALITE. 155 1 1 9 Silica. Alumina 27-90 27-37 27-30 Lime. Soda. Potash. Water. Chlorine. Total. 49-30 50-29 49-20 14-42 13-53 15-48 5-46 5-92 4-53 : 17 1-23 0-90 1-20 0-92 97-9S 97-30 99-66 Fuchs. v. Kobell. Schafhautl. According to a more recent analysis of Fuchs, this mineral contains 7'83 per cent, chloride of sodium, and may be represented by 4 j si 2 + 4 ca si 4- Na Ci = 49-72 silica, 27-48 alumina, 14-97 lime, and 7-83 chloride of sodium. Schafhautl states that the whole chloride is vo- latile at a strong red heat. It occurs at Obernzell near Passau, either massive in a bed in granite, or loose and crystallized in the mines of porcelain earth. 41. SODALITE, Thomson, Hauy, Phillips, fyc. ; Dodecahedral Am- phigene-spar, Mohs. Tesseral; ooO(fig.3). Also massive and distinct granular. Cleavage dodecahedral along ooO, more or less perfect. Fracture conchoidal or uneven. H. = 5*5 ; G. = 2-28 2-29. Translucent. Lustre vitre- ous, inclining to resinous. Colourless, but coloured in various shades of white, grey, green, and rarely blue. B.B. becomes white and fuses easily alone, sometimes intumescing, to a clear glass ; with difficulty in borax. Gelatinizes with acids. Chem. com. 3 '&\ si + 3 Na si + Na Ci =37-8 silica, 83*3 alumina + 25'3 soda, and 5-6 chlorine. Analyses. Silica. Alu- mina. 32-00 27-48 2375 3550 32-04 32-88C 30-93 Soda. Lime. Iron perox. Muriatic acid. Total. 1 36-00 2 38-52 3 44-87 4 33-75 5 38-40 6 37-30 7 37-63 25-00 23-50 27-506 26-23 24-47 23-86 25-48 2-70 : 32 0-59d 0-15 1-00 0-12 1-08 6-75 3-00 a 3-76 5-30 7-no 6-97 e 99-90 98-30 100 100-78 102-53 100-60 Ekeberg, Greenland. Thomson, do. Borkowsky, Vesuvius. Arfvedson, do. Hofmann, Ilmen M. Whitney, Litchfield. Do. do. 'a) + 2-10 volatile matter; (6) with potash ; (c) with iron perox. ; (d) potash; (e] chlorine. Occurs in Greenland, in a bed in mica slate, along with felspar and eudialyte, and is pink when newly fractured, but becomes green on exposure. On Vesuvius of a white colour, in ejected dolomite blocks with nepheline, ryacolite, mica, hornblende, and garnet ; more rarely in recent lava on Vesuvius ; also in the Valle di Noto in Sicily, and near Lake Laach. In the Ilmen hills Ural, in miascite with felspar and nepheline ; at Fredriksvarn in Norway, and more recently, of a blue colour from iron, at Litchfield in Maine. According to Mr Whitney it forms (like cancrinite, hauyne, nosean, and nepheline) a clear solution in acids, and consists of (Na'sY + 3 Al'sOi + NaCl. the first member being common to all these minerals. 156 HAUYNE NOSEAN. [Haloid Stones 42. HAUYNE, Neergaard, Hauy, Phillips ; (with nosean) Dodecahe- di-al Amphigeue-spar, Mohs. Tesseral ; chiefly ooO, but more common in crystalline grains ; mostly disseminated singly. Cleavage dodecahedral along ooO, more or less perfect. H. = 5 5*5 ; G. = 2*4 2*5- Semitransparent or translucent ; lustre vitreous or resinous ; colour azure or sky blue ; streak bluish- white. B.B. decrepitates violently, and melts to a bluish -green vesicular glass. Soluble in hydrochloric acid to a clear fluid, with scarce a trace of sulphuretted hydrogen. Analyses. Silica. Alumina. Iron perox. Lime. Soda. Potash. Sulphuric acid. Total. ] 35-48 18-87 1-16 12-00 15-45 12-39 a 100 L. Gmelin. "2 3 4 35-01 32-44 33-90 27-42 27-75 28-07 0-17 b 12-55 9-96 7-50 9-12 14-24 19-28 2 : 40 12-60 c 1298 12-01 98-34 99-77 100-76 Varrentrapp. Whitney. Do. 5 34-83 28-51 0-31 7-23 18-57 ... 12-13 101-58 Do. (a) + 3-45 sulphuretted hydrogen and loss; (b) iron; (c) + 0'24 sulphur, 0'58 chlorine, 0-62 water. From (1) Marino; (2, 4, 5) Niedermendig ; (3) Mont Albano. The analyses do not very well agree, but the formula (N a , k,) 2 si + Ai 2 si 8 + ca s* = 34-8 silica, 28'9 alumina, 17-2 soda, 7'9 lime, and 11 '2 sulphuric acid, represents them pretty nearly. Rammels- berg gives [(Na 3 , K 3 ,) sV + 3 1 'sY J+ 2 cVs' for the Mont Albano variety, and regards that from Niedermendig as mixed with sodalite. This mineral is found in the ejected blocks on Vesuvius ; in lava on Mount Vultur near Melfi, the Campagna of Eome, and Nieder- mendig near Andernach ; in peperino at Albano and Marino. Also it is said in Auvergne and the Cantal in a basaltic or phonolite rock. 43. NOSEAN, Klaproth ; Spinellane, Hauy, Phillips. Tesseral ; like hauyne in form and cleavage, but oftener in granular masses. H. = 5'5 5 G. = 2-25 2-27. Translucent or only on the edges ; lustre vitreous, inclining to resinous ; colour ash" or yellowish- grey, sometimes blue, brown, or black. B.B. becomes paler, and melts on the edges to a vesicular glass. Soluble in acids, without any trace of sulphuretted hydrogen (Whitney). Analyses of the va- riety from Lake Laach. 1 2 3 4 8 6 Silica. Alu- mina. Iron "JperoxJ Lime. Soda. Sulphuric acid. Chlo- rine. Water. Total. 43-00 38'50 37-00 35-99 36-52 36-53 29-5 29-25 27-50 32-57 29-54 29-42 2-0 1-506 1-156 0-04 e 0-44 0-44 1-5 1-14 8-14 1-12 1-09 1-62 19-0 16-56 12-24 17-84 23-12 22-97 .. a 8-16 c ll-5fid 9-17 7-66 7-13 : 65 0-61 0-61 2-5 1-85 1-37/ 1-37/ 98-5 99-11 99-59 99-23 100-34 100-09 Klaproth. Bergmann. Do. Varr entrap n. Whitney. Do. (a) +1-0 sulphur; (6) protoxide; (c) + 1 -00 manganese protox., 3-00 sulphuretted hydrogen; (d) 0-50 mangan. prot., T50 sulph. hyd. ; (e) iron; (/) loss by heat. Family.'] ITTNERITE LAPIS -LAZULI. 157 Whitney's analyses would give nearly 3 (N si + \ si ) + Na '', (or (Na 3 'sY + 3 ii sY) + Na 's , Rammelsberg), = 36'65 silica, 30*59 alumina, 24*82 soda, and 7*94 sulphuric acid. Nosean occurs in various places near Andernach on the Rhine, as at Lake Laach, in loose blocks of a crystalline compound of glassy felspar, hornblende, augite, and magnetic iron ; at Rieden in leucite- porphyry ; and at Niedermendig and Mayen in the so-called millstone lava. The blue variety is perhaps hauyne, and a similar mineral in the pumice of Pleit, and the trass of Tonnisstein, is also not certainly determined to be nosean. 44. ITTNERITE, C. Gmelin, Phillips. Tesseral, but only found in coarse granular aggregates ; cleavage, dodecahedral distinct. Fracture imperfect conchoidal ; H. = 5*5 ; G. == 2'37 2-40. Translucent ; resinous lustre ; colour smoke, ash or dark bluish-grey. In the closed tube yields much water. B-B. fuses, with much effervescence and sulphurous smell to a vesicular opaque glass. In borax forms a clear glass. Does not form a clear solution, but gelatinizes in concentrated hydrochloric acid. Analyses. 1 2 Silica. Alu- mina. Iron perox. Lime. Soda. Pot- ash Sulph. acid. Chlo- rine. Water. Total. 34-02 35-69 28-40 29-14 0-62 7-27 5-64 12-15 12-57 1-56 1-20 2-86 4.62 075rt 1-25 107fi6 9-83c 98-39 100 C. Gmelin. Whitney. (a) Hydrochloric acid ; (6) with sulphuretted hydrogen ; (c) and loss. The composition of this mineral is very complex, but Rammels- berg divides it into two compounds one sodalite and water, the other a hauyne (with only half the sulphate of lime) and water. It is found in the dolerite of the Kaiserstuhl in the Breisgau. The water distinguishes it from all the similar compounds. Sodalite, hauyne, nosean, and ittnerite agree in form, mode of oc- currence, and other points, and the last three are often considered one species. They all contain the same double-silicate united in the first with Na ci in the second with Na 's', in the third with 2 ca 's', whence the isomorphism of these latter substances might be inferred. 45. LAPIS-LAZULI, Wallerius, Phillips; Lasurstein, Werner; -Lazulite, Hauy ; Sappheirus, Theophrastus, frc. Tesseral ; o>0, but rarely distinct. Generally massive and in fine granular aggregates. Imperfect dodecahedral cleavage ; H. =5*5 ; G. = 2-38 2-42. Translucent on the edges ; dull resinous or slightly- vitreous lustre ; colour ultramarine or azure-blue of various intensity. 158 EUDIALITE. [Haloid Stones Streak light-blue. B.B. loses its colour and fuses readily to a white porous glass. In borax effervesces and forms a clear glass. In hy- drochloric acid the powder speedily loses its colour, is dissolved and gelatinizes, evolving sulphuretted hydrogen. Chein. com. indeter- minate. Analyses. I Si- | lica. Sul. acid. Alu- mina. Soda Lime Mag- nesia. Iron perox. Chlo- rine. Sul- phur. Watr. Total. 1 46-0 4-0 14-5 17-5 30 2-Oa 97-0 Klaproth. 2 49- 2 11 8 16 2 4 ... trace trace 92 L. Gmelin. 3 45-50 4 35-8 5-89 31-76 34-8 9-09 23-2 3-52 3-16 ... Q-86d 042 0-95 3-1 0-12 98-11 100-0 Varrentrapp. C. and D. 5 4660 3-83 23-30 21-48 0-02 (17)c 1-Odd trace 1-69 ... 99-73 Varrentrapp. (a) + lO'O carbonic acid; (ft) = carbonate of lime; (c) potash; (d) iron. 1, 2, 3, mineral ; 4, ultramarine prepared from stone, by Clement and Desormes; 5, arti- ficial ultramine used in the porcelain manufactory at Meissen. Found chiefly in granular limestone ; as on the shore of lake Baikal, near granite. It is mostly brought from China, Thibet, and especially Badakschan in Tartary. It is used for ornamental pur- poses, and the preparation of ultramarine-blue. The colour both in it arid the hauyue seems caused by some compound of sulphur, pro- bably with iron. A mode of preparing the artificial colour was first discovered by Chr. Gmelin. According to Varrentrapp the colour becomes more intense with the amount of iron. The lapis-lazuli often contains scales of mica and iron pyrites the gold scales noticed by the ancients in the sapphire. 46. EUDIALITE, Stromeyer, Hauy, Phillips ; Khombohedric Almandine-spar, Mohs. Rhombohedric ; R 73 24' ; usual combination R . OR . ooP2 . R, also massive and granular. Cleavage, basal distinct ; along |R (126 13') less distinct. Fracture uneven ; H. = 5 5*5 ; G. = 2'84 2*95. Semitranslucent or opaque. Lustre vitreous. Peach- blossom to brownish- red. Streak white. B.B. fuses easily to a light- green opaque glass. In salt of phosphorus the silica intumesces so much that the bead loses its spherical form. Gelatinizes in hydro- chloric acid. Analyses. 1 2 3 Silica. Zir- conia. Lime. Soda. Iron perox. Man- ganese perox. Muria- tic acid. Water or loss by heat. Total. 52-48 64-10 4992 10-90 11-58 16-88 10-14 1080 11-11 13-92 11-40 12-28 6-86 7-86 6-97& 2-57 2-93 1-156 1-03 0-30 1-19C 1-80 l-66a 0-3d 99-70 101-55 100-52 Stromeyer. Pfaff. Rammelsberg. + 0'92 copper oxide ; (6) protoxide; (c) chlorine ; (d) +0'65 potash. Family] . ANALCIME. 159 Rammelsberg gives the rather complex formula, Na ci + 4 [2(da, Na, Fe) s 'si' 2 + z'r "si 2 ] ; but rejecting the chlorine as not essential, this becomes 2 R 3 sY 2 + z'r si" 2 . He also considers that in Stromeyer's analysis the iron and manganese should be taken as protoxide, (6*16 and 2'31), and the muriatic acid as I'OO chlo- rine, whilst a portion of the zirconia was not separated from the silica. Pfaff thought he found a new metallic oxide in the silica (Tantaline) ; and Svanberg recently some new earths in the zirconia. Eudialite has only been found at Kangerdluarsuk in Greenland in gneiss along with sodalite, arfvedsonite, and felspar. It much re- sembles almandine garnet, but is distinguished by its crystallization, lower specific gravity, inferior hardness, and action before the blow- Pipe. VI. FAMILY. ZEOLITES. 47. ANALCIME, Hauy, Phillips, Werner, Sfc. ; Hexahedral Kuphon-spar, Mohs. Tesseral ; generally 2O2, seldomer ooOoo . 2O2 (fig. 115). Fig. 115. The crystals mostly united in druses ; but also in granular masses. Cleavage hexahedal veiy i m P er f ect - Fracture uneven. H. = 5*5 ; G. = 2-1 2-25. Transparent to translu- cent on the edges. Lustre vitreous, rarely pearly. Colourless, but white, greyish, green- ish, yellowish, or reddish white ; also flesh- red, and very rarely leek-green. In closed tube yields water, and becomes milk-white. B.B. melts quietly to a clear glass. Com- pletely soluble and gelatinizes in hydrochloric acid. Chem. com. Ai si 8 + Na si + 2n = 55*2 silica, 22-9 alumina, lb'9 soda, and 8 water. Analyses. Silica. Alu- mina. Soda. Potash. Lime. Wtr- Total. 1 58-0 18-0 10-0 2-0 8-5 96-5 Vauquelin, Montecchio Maggiore. 2 55 12 22-99 13-53 8-27 99-91 H. Rose, Catania. 3 56-47 21-98 1378 8-81 100-99 Do. Fassavalley. 4 56-07 22-23 13-71 8-22 99-23 Connel, Old Kilpatrick. 5 57-34 6 55-60 22-58 23-00 11-86 14-65 0-55 0-35 9-00 7-90 101-68 101-15 Henry, Blagodat. Thomson, Giants' Causeway. 7 55-16 23-55 14-23 trace trace 8-26 101-20 Awdejew, Lon, Brevig. 8 57-50 9 56-12 23-15 24-00 6-45 6-45 0-10a 0-15a 5-63 5-82 8-00 8-00 100-83 100-54 Riegel, Niederkirchen. Do. Do. 10! 51-27 23-56 5-13 7'31a 1-236 10-55 99-05 Thomson, Kilpatrick Hills. (a) Iron peroxide ; (&) magnesia. 160 NATROLITE. {Zeolite Chiefly found in amygdaloidal cavities or fissures in trap, basalt, or trachyte rocks. Fine large crystals occur in the Southern Tyrol (Seisser Alpe), near Dumbarton in Scotland, and at Almas and Tokerb in Siebenburg. Smaller crystals are found in the Cyclopean islands near Sicily, the Vicentine, in Faroe, Iceland, Nova Scotia, and also in the Hebrides, Glenfarg, Salisbury Craigs, and other parts of Scotland. More rare in the older rocks, as in drusy cavities of the zircon syenite of Laurvig and Brevig in Norway, in magnetic iron-ore at Arendal, and Blagodat in the Ural ; and in the silver veins of Andreasberg in the Hartz. Sir D. Brewster states that when analcime crystals are divided into twenty -four equal parts, by planes passing through the centre parallel to the faces of the dodecahedron, each of these parts has a peculiar optical structure and double refrac- tion. (Edin. R. S. Trans, x. 187.) No. 3 has been named Sarcolite, but is only a variety as well as the Cuboit of Breithaupt (No. 5), massive, with distinct cleavage, greenish-grey, and G. = 2-24 2'28. The Cluthalite of Thomson (No. 10), from near Dumbarton, opaque and flesh-red, H. = 3'5, is also probably a connected species. 48. NATKOLITE, Werner ; Mesotype, Hauy, Phillips, Levy, Sfc. ; Prismatic Kuphon-spar, Mohs. Rhombic ; ooP 91, P polar edges 143 20', and 142 40' (= 143 20'), middle edges 53 20' ; generally only o>P . P, seen fig. 116. Fig. 161. Crystals, fine prismatic, acicular or fibrous ; united in re- niform masses, sometimes apparently compact. Cleavage, prismatic along o>P perfect ; H. = 5 5'5 ; G. = 2-17 2-26. Translucent, or only on the edges ; lustre vitreous ; colourless, or greyish-white, but sometimes bluish, yel- lowish, or ochre-yellow, seldom red or brown. Is not pyro-electric. B.B. becomes obscure and melts quietly to a clear glass. Gelatinizes in hydrochloric acid, also perfectly dis- solved by oxalic acid. Chem. com. Xi si 2 -I- Na si + 2 H ; = 48 si- lica, 26-6 alumina, 16' 1 soda, and 9 -3 water. Analyses, next page. Occurs chiefly in amygdaloid, basalt, dolerite, and clinkstone, either in veins, druses, or disseminated. More rarely in plutonic and primary rocks, as at Laurvig and ArendaL Fine crystals are found in Auvergne, and at Alpstein in Hessia ; the yellow fibrous variety at Hohentwiel in the Hbgau. Common in various parts of Scotland, as in Mull, Canna, and near Tantallan Castle ; and in Ireland, Nova Scotia, and other countries. TheBergmannite an&Radiolite are merely varieties. Family.'] SCOLEZITE. 161 Silica. Alumina. Soda. Potash. Lime. Iron perox. Water, Total. 1 4776 25-88 16-21 ... ... ... 9-31 99-16 Fuchs, Auvergne. 2 48-17 26-51 16 12 0-17 9-17 100-10 Do. do. 348-04 2503 1676 ... ... 9-65 99-48 Thomson, do. 4 47-56 26-42 14-93 l'-40 0-58 10-44 101-33 Do., Antrim. 5 47-21 25-60 16-12 1-35 888 99-16 Fuchs, Hogau. 6 48-63 24-82 15-69 0-21 9-60 98 '95 Do. Tyrol. 7 46-94 27-00 14-70 1-80 9-60 100-04 v.Kobell, Greenland. 8 47-34 27-21 14-61 l"34 9-47 99-97 Sander, Iceland. 9 48-05 10 47-97 25-80 26-66 15-75 14'07 trace. 0*-68 2-To 0-73 9-OH 9-77 10070 jRiegel, Hogau. 99 88 Scheerer, Norway. 11 48-12 26-96 14-23 trace. 0-69 0-22 10-48 100-70 Do. do. 12 48 '38 26-42 13-87 1-54 0-44 0-24 9-42 100-31 Do. do. Nos. l^i are glassy ; 5-9, fibrous natrolite ; No. 10, flesh red, and 11, white bergmannite ' No. 12, radiolite, 49. SCOLEZITE, Fuchs ; Needlestone, Phillips ; Lime mesotype ; Harmophane Kuphon-spar, Mohs. Monoclinohedric, C = 90 54', ooP 91 35', P 143 29', P 144 20', usual combination o>P . P . P ; crystals, short or long, pris- matic or acicular. Twin crystals very common, united by a face of Fig. 117. cPo > and the chief axis also the twin axis, the two crystals forming apparently one individual (fig. 117.) Also massive, with radiating fibrous texture. Cleavage prismatic, along ooP rather perfect ; H. = 5 5'5 ; G. = 2*2 2'3. Transparent or translucent on the edges. Lustre vitreous, fibrous varieties silky. Colour- but snow-white, greyish, yellowish, and reddish-white. It usually shows very distinct pyro-electricity, the diverging ends being antilogue, the converging analogue. B.B. bends and twists in a vermicular manner, and melts easily to a porous glass. In hydro- chloric acid dissolves and gelatinizes ; also soluble in oxalic acid, leaving oxalate of lime. Chem. com. ii's'i 2 + ca si 4- 3k, with 46'6 silica, 25'8 alumina, 14 lime, and 13.6 water. Analyses. Silica. Alum. Lime. Soda. Water. Total. 1 49-0 26-5 153 9-0 99-8 Guillemin, Auvergne. 2 48-94 2599 10-44 13-90 99-27 Fuchs andGehlen, Iceland. 3 46-19 25-88 13-86 V 48 13-62 100-03 Do. Faroe. 4 47-00 26-13 9-35 5-47 12-25 100-20 Do. Do. 5 46-80 26-50 9-87 5-40 12-30 100-87 Berzelius, Do. 6 46-78 25-6-6 10-06 4-79 1231 9960 Fuchs and Gehlen, Iceland. 7 47-46 25-35 10-04 4-87 12-41 100-13 Do. Do. 8 46-04 27-00 9-61 5-20 12-36 100-21 Do. Tyrol. 9 4675 24-8-2 14-20 0-39 13-64 9980 Do. Stafla. 10 46-76 , 26-22 13-fi8 13-94 100-60 Giilich, Iceland. 11 4672 25-90 1371 13-67 100 Gibbs. do. 12 48-08 23-93 14-23 0-33 13-55 100-12 Riegel, Nierierkirchen, (m. of 2). 13 48-88 26-36 7'64 4-20a 12-32 101-86 Thomson, Giants* Causeway. 14 46-00 27-60 15-20 14-35 103-15 Do. do. 15 48-03 26-66 547 8-32 1172 100-20 Do. Kinross. 16 42-19 30-41 4-91 12-55 10-97 101-02 Do. Antrim. (a) + 2-46 magnesia. 1-5, Crystalline; 6-10, fibrous rarieties ; (3-8) the mesolite of Fuchs. O 162 SCOLEZITE. [Zeolite Occurs in vesicular cavities in amygdaloid, basalt, and similar rocks, along with stilbite and other zeolites. Very fine specimens found in Staffa, at Berufiord in Iceland, in Faroe, Greenland, and the Vendyah Mountains in India. Also in Tyrol, Ireland, &c. The mesolite of Fuchs appears from the researches of G. Rose to be in some cases a scolezite containing soda, in others natrolite, with lime, or perhaps a mixture of 2 atoms of the former mineral, with 1 of the latter. In a variety from the Giants' Causeway, Thomson found the interior portion (No. 13) different from the exterior (No. 14), the latter being scolezite, the former mesolite, and likewise an amount of magnesia, unexampled in this mineral. Nos. 15 and 1 6 by the same chemist also show some peculiarities, the latter especially in the proportion of silica. The following minerals, sometimes described as distinct species, are either mere varieties of, or very closely allied to, scolezite or natrolite. The Caporcianite of Savi, a reddish-grey, radiating fibrous mine- ral, from Caporciano, near Monte Catini in Tuscany. Lehuntite of Thomson, from amygdaloid Glenarm, Ireland, fine sealery flesh-red, G. = 1-953 ; H. = 3 '75. Poonahlite of Brooke, forming rhombic prisms of 92 20', otherwise like scolezite, from Poonah in Hindostan. Mesole of Berzelius, radiating, fibrous ; transpa- rent and pearly ; white, yellow, or grey ; G. = 2'35 ; H. = 3*5 from Faroe, Schonen, &c. Brevicite of Berzelius, radiated, massive, white, reddish-grey, or dark-red, in vesicular cavities of a plutonic (trachytic ?) rock near Brevig. Yields water in the closed tube ; B.B. melts to a clear porous glass. Harringtonite, Thomson, com- pact, earthy, snow-white, from amygdaloid of Portrush, in Ireland. Antrimolite, Thomson, white, fibrous, and opaque ; G. = 2*096 ; H. = 3 '75 ; from Antrim, Ireland. Stellite, Thomson, crystallized apparently in fine rhombic prisms grouped in concentric stars. White, translucent, silky, H. = 3 3*5 : G. = 2*612. From greenstone, eastwards from Kilsyth, Scotland. Analyses of these as follows. Silica. Alum. Lime. Soda. Potash. Water. Total. 1 52-8 21-7 11-3 0-2 1-1 13-la 100-7 Anderson, Caporcianite. 2 47-33 24-00 1-52 13-20 13-60 99-65 Thomson, Lehuntite. 3 45-12 30 '45 10-20 0-66 trace 13-39 99-81 C. Gmelin, Poonahlite. 4 42-60 28-00 11-43 5-63 12-70 100-36 Berzelius, Mesole. 5 42-17 27-00 9-00 10-19 ... 11-79 100-15 Hisinger, do. 6 41-52 26-80 8-07 10-81 ... 11-79 98-99 Do. do. 7 42-70 27-50 7-61 7-00 ... 14-71 99-52 Thompson, do. 8 43-88 28-39 6-88 10-32 0-21& 9.63 99-31 Sonden, Brevicite. 9 10 44-84 43-47 28-48 30-26 10-68 7-50 5-56 0-19C 410 10-28d 15-32e 99-84 100-94 Thomson, Harringtonite. Do. Antrimolite. 11 48 '47 5-30 30-96 3-53C 5-585 6-11 99-95 Do. Stellite. (a) + 0-1 iron peroxide, 0-4 magnesia ; (&) magnesia; (c) iron protoxide ; (d) with trace of muriatic acid ; (e) -f 0-098 chlorine. From (4) Faroe; (5, 6) Annaklef in Schonen; (7) Bombay. Family. ,] DAMOURITE THOMSONITE. 163 50, DAMOURITE, Delesse. Massive and fine Mated. H. = 1-5 ; G. = 2-7 2-8. Translu- cent on the edges ; lustre pearly ; colour yellowish-white. B.B. yields water, intumesces, becomes milk-white, and melts with diffi- culty to a white enamel. With cobalt solution becomes blue. Not affected by hydrochloric, but decomposed by sulphuric acid, leaving silica in the form of the scales. After ignition the acid has no effect. Analysis. Silica. Alumina. Potash. Water. Total. 1 45-22 37-85 11-20 5-25 99-52 Damour, m. of 2. This analysis gives the formula 3 A! si + K si + 2 H ; or (&i si 3 + K si) + 2 jin , of which the first part is orthoclase, the other diaspore. The action of the mineral with acids, so different from the zeolites of similar composition, seems to show that it is really a mix- ture. It occurs at Pontivy in Dpt. Morbihan in Brittany, forming the matrix of cyanite and staurolite. The mica slate of St Gotthardt, also enclosing these minerals, named Paragonite by Schaf hautl, is similar externally, but contains 50 '20 silica, 35 '90 alumina, 2-36 iron peroxide, 8'45 soda, and 2'45 water ; and is infusible B.B. 51. THOMSONITE, Brooke ; Comptonite, Brewsler ; Orthotomous and Peritomous Kuphone-spar, Mohs. Rhombic, ooP 90 40', the comptonite usually in the combination ooPoo . ooPoo .ooP . xP, (fig. 118). xPco is an extremely obtuse Fig 118. dome of 177 35', and appears like the basis with the plane broken, which is very characteristic of the crys- tals. In druses, fan-shaped and scopiform, or radiated aggregates. Cleavage, macrodiagonal and brachydia- gonal, both equally perfect ; H. = 5 5'5 ; G. = 23 2 -4. Translucent, but often obscure. Vitreous, sometimes pearly. Colour white. B.B. intumesces, becomes opaque, and fuses with difficulty to a white enamel. Soluble and gelatinizes in hydrochloric acid. Chem. com. 3/u si + 3c a si 4- 7k = 38*2 silica, 31 '6 alumina, 17-2 lime partly replaced by soda, and 13 water. Analyses, next page. Occurs with calcspar and other zeolitic minerals in cavities in amygdaloid, basalt, dolerite, clinkstone, and old lavas ; as on Vesu- vius, in Sicily, Bohemia, Tyrol, Iceland, Faroe, Scotland, and Nova Scotia. In crystallisation as well as in chemical and physical cha- racters, Thomsonite, named after the well-known chemist, and Comp- tonite agree, and the Chalilite of Thomson is perhaps only a compact variety. 164 STILBITE. [Zeolite Silica. Alu- mina. Lime. Soda. Mag- nesia. Iron perox. Water. Total. 1 38-30 30-70 13-54 4-53 13-10 100-17 Berzelius. 2 38-5 30-6 126 4-8 M ... 13-5 100 L. Gmelin. 3 34-63 32-35 18-65 1-25 14-00 100-88 Thomson. 4 37'OS 33-02 10-75 3-70 ... 13-00 97-55 Do. 5 36-80 31-36 15-40 ... 020 0-60 13-00 97-36 Do- 6 37-56 31-96 15-10 108 0-72 13-20 99-62 Do. 7 39-20 30-05 10-58 8-lia 0-50 13-40 101-84 Retzius. 8 37-00 31-07 12-60 6-25 ... 12-24 99-16 Melly. 9 38-25 32-00 11-96 6-53 ... ... 11-50 100-24 Zippe. 10 38-74 30'84 13-43 3-85 0-54& 13-10 100-50 Rammelsberg. (a) with potash ; (6) potash. Nos. 1-7, Thomsonite"; 8-10, Comptonite. From (1-4) Kilpatrick Hills, Dumbarton; '5, 6) Lochwinnoch, Scotland ; (7) Dalsmypen, Faroe ; (8) Elbogen ; (9, 10) Seeberg, near Kaaden, Bohemia. ; 52. STILBITE, Hauy, Phillips ; Desmine, Breithcwpt, Naumann, Hausmann ; Prismatoidal Kuphon-spar, Mohs. Rhombic ; polar edges of the pyramid P 119 15', and 116 ac- cording to Kbhler ; usual combination, ooPco (M ) . ooPoo (T) . P- Fig, 119. F (r) OP . (P) (fig. 119), sometimes also with ocP. The crystals broad pyramidal, very often in fas- cicular or diverging groups ; also massive, in radiating, broad columnar aggregates ; or macled. Cleavage, macrodiagonal very perfect ; H. = 3'5 4 ; G. = 2-1 2-2. Translucent, or only on the edges ; lustr e vitreous, but pearly on ooPco . Colourless, but white, red, grey, yellow, and brown. B. B. intumesces greatly, and melts with difficulty to a white enamel. Decomposed by concentrated hydrochloric acid without gela- tinizing, but leaves a slimy siliceous powder. Chem. com. i si 3 + c'a si 3 + 6 H = 58-2 silica, 16 alumina, 8*8 lime sometimes partly replaced by soda or potash, and 17 water. Analyses. M Silica. Alumina. Lime. Soda. Potash. Water. Total. 1 55-07 16-58 7-58 1-50 19-30 100-03 Fuchs and Gehlen, Iceland. a 5800 16-10 9-20 16-40 99-70 Hisinger, do. ;$ 56-08 17-22 6-95 2-17 18'35 10077 Retzius, Naalsoe in Faroe. 4 57-05 16-49 7-65 1-33 0-26 17-79 100-50 Moss, Faroe. 6 60-27 14-43 6-40 0-216 ... 18-.W 99-71 Zellner, Nimptsch, Silesia. r, 5575 18-50 8-05 3-0 0-01 c 1700 99-31 G. Leonhard, Rienthal, Uri. 7 55'0 167 6-5 3-0 d 188 100 Delesse, Faroe. 8 !) 58-53 58-37 1573 16-90 7-02 6-98 3-07e 1-62 0-50 c 0-23 c 17-05 14-50 101 90 98-60 Munster, Christiana. Riegel, Niederkirchen. (a) Alkali ; (6) magnesia ; (c) iron perox. ; (d) with loss ; (e) alkali and magnesia. Nos. 4, 6, 9, means of two; No. 8, a bright yellow radiated variety, G. = 2-203. Family. ~\ AEDELFORSITE HEULANDITE. Occurs in metallic veins at Andreasberg in the Hartz, Konigsberg in Norway, and Arendal ; also in beds of magnetic iron ore, and in fissures or druses of granite, gneiss, and other primary strata. Most commonly in amygdaloids with other zeolites, calc-spar, and green earth. Iceland, Faroe, and the Vendayah Mountains in Hindostan, furnish the finest crystals. In Scotland, flat four-sided prisms occur in Skye, brick-red crystals at Kilpatrick, and brown at Kilmalcom. In Arran it is found in decomposed porphyry. It is rare in basalt and clinkstone. The Sphserostilbite (No. 1 below) and Hypostilbite (No. 2) ofBeu- dant, both from Faroe, are closely related to this species, but the for- mer gelatinizes with acids, and the latter was probably weathered. With them the two varieties of stilbite (Nos. 3 and 4) from Dumbar- ton agree. Analyses. 1 2 3 4 Silica. Alumina. Lime. Soda. Water. Total. 55-91 52-43 54-80 52-50 16-61 18-32 18-20 17-32 9-03 8-10 983 11-52 0-68 2-41 17-84 18-70 19-00 18-45 100-07 99-96 101-83 99-79 Beudant. Do. Thomson, white. Do. red. 53. AEDELFOKSITE, Retzius. Massive, and fibrous or columnar. Cleavage, probably along a rhombic prism. H. = 6 ; G. = 2'6. Translucent on the edges. Colour white, light grey, and reddish. B.B. fuses with intume- scence ; soluble and gelatinizes in acids. Chem. com. i si 3 + c a si 3 -f- 4 H, or stilbite with two atoms less water. Analysis. Silica. Alumina. Lime. Iron perox. Magnesia and Mang. protox. Water. Total. 1 60-28 15-42 8-18 4-16 0-42 11-07 99-53 Retzius. Occurs at Aedelfors in Sweden. Another very distinct mineral from this locality has received the same name. -j 54. HEULANDITE, Brooke, Phillips; Stilbite, Hauy, Hausmann, Naumann ; Hemiprismatic Kuphon-spar, Mohs. Fig. 120. Monoclinohedric ; C = 63 40', Poo 50 20', usual combination, ( coPoo ) . ooPoo . Poo . OP, to which oc- casionally small triangular faces of the hemipyramids 2P and P are associated (fig. 120). The crystals mostly tabular, more rarely prismatic in the direction of the orthodiagonal, are conjoined in druses or radiated lamellar concretions. Cleavage, clinodiagonal very per- fect ; brittle ; H. = 3'5 4 ; G. = 2'1 2-2. Trans- 166 BREWSTERITE. [Zeolite parent to translucent on the edges; lustre vitreous, or pearly on (GO Poo). Colourless, white, but often coloured, especially flesh or brick-red, and yellowish or hair-brown. B.B. exfoliates, intu- mesces, and melts to a white enamel. Soluble in hydrochloric acid, leaving slimy silica, but without gelatinizing. Chem. com. 4 AI si 3 + 3ca s\ 3 + 20 H, with 58'1 silica, 18*4 alumina, 7*5, lime and 16 water. Analyses. Silica. Alu- Iron Lime. Water. Soda. Total. 1 60-07 17-08 0'20 7-13 15-10 99-58 Walmstedt. 9 59-15 17-92 7'65 15-40 100-12 Thomson, Faroe. 3 4 58-2 59-64 17-6 16-33 (074) a 7-2 7-44 16-0 14-33 l"l*6 99-0 99.64 Rammelsberg, Iceland. Damour. 5 64-2 141 1.26 4-8 13-4 0-6 100 Delesse, Baltimore. (a) potash; (6) ironprotox. + 1'7 magnesia. Occurs rarely in primary rocks, as in gneiss at Hadlyme, Ct., Chester, Mass., Bergen Hill in New Jersey, and other parts of K America ; in beds of ore at Arendal, and in metallic veins at Kongs- berg and Andreasberg. It is more frequent in amygdaloid, or in basalt, as in Iceland, Faroe, Cape Blomidon in Nova Scotia, and the Vendayah Mountains, Hindostan. Red varieties are found in the Fassa valley, at Campsie in Stirlingshire, in Skye, and other parts of Scotland. According to Breithaupt, this mineral belongs to the triclinohedric system, with which the twin crystals seem to correspond. The Beaumontite of LeVy (No. 5), from near Baltimore, is said by Dana to be only Heulandite ; but Levy describes the fundamental form as a tetragonal pyramid of 147 28' and 46 40' (vide Hausmann). The crystals are very small, and of a pale or honey-yellow colour. Delesse's analysis has probably been mixed with quartz ; as the solu- bility in acids of so siliceous a compound is very remarkable. 55. BKEWSTERITE, Brooke, Phillips, frc. ; Megallogonous Kuphon- spar, Mohs. Monoclinohedric ; the crystals appear short prismatic, formed by several vertical prisms, and the clinopinacoids, and bounded by an extremely obtuse almost horizontal clinodoma (172) which peculiarly Fig. 121. characterizes them (fig. 121). They are mostly small, striated vertically, and united in druses. Cleavage, cli- nodiagonal very perfect ; H. = 5 5'5; G. = 2*12 2-2. Transparent or translucent ; lustre vitreous, on (ooPoo) pearly. Streak white. Colour white, grey, yellow, brown, or green. B.B. froths, intumesces and fuses to a porous glass. Soluble in hydrochloric acid Family^] EPISTILBITE. 167 with separation of silica (perfectly gelatinizing, v Kobell). This solution yields with sulphuric acid a deposit of sulphate of barytes and strontia. Chem. com. nearly 4 i si 3 + (2 s'r + Ba) s'i 3 + 18 H, = 54*3 silica, 17*1 alumina, 8 '7 strontia, 6*4 baryta with lime, and 13-5 water. Analyses. Silica. Alu- mina. Stron-l Ba- tia. ryta. Lime. Iron perox Watr. Total. 1 5367 2 53-05 17'49 16-54 8-33 6-75 9-01 | 6-05 1-35 0-80 0-29 12-58 14-73 100-46 100-18 Connell, Strontian. Thomson, do. Occurs with calc-spar in veins at Strontian, Scotland ; and in amygdaloid at the Giants' Causeway. Also in the lead mines of St Turpet, near Freiburg in the Breisgau, in the Isere Dept. in France, and in the Pyrenees. 56. EPISTILBITE, G. Rose, Phillips; Diplogenous Kuphon-spar, Mohs. Rhombic, ooP 135 10', Poo 109 46', PQO 147 40'. These three forms usually compose the crystals (fig. 122), which are lengthened prismati- . cally along ooP. Macles united by a face of o>P are more '" '_ common. It also occurs massive and granular. Cleav- age, brachydiagonal very perfect. H. = 3*5 4; G- = 2 2-2. Transparent or translucent on the edges. Lustre vitreous, or pearly on the cleavage planes. Co- lourless or white. B.B. melts with intumescence to a porous enamel, which becomes blue with cobalt solution. Soluble without gelatinizing in concentrated hydrochlo- ric acid, but after ignition is insoluble. Chem. com. 1 Si 3 + c a s'i 3 -f. 5ri, =59 silica, 17*5 alumina, 9 lime, with soda, and 14-5 water. Analyses. M M I Silica. Alu- mina. Lime. Soda. Water. Total. 1 58-59 2 1 60.28 17-52 17-36 7-56 832 1-78 1-52 14-48 12-52 99-93 100 G. Rose. Do. Occurs with stilbite and scolezite in Iceland and Faroe. Also, it is said, in the basalt of the Siebengebirge on the Rhine, and in Ire- land. Brewster has shown that in epistilbite there is only one sys- tem of polarized rings ; in heulandite two. 168 APOPHYLLITE. [Zeolite 57. APOPHYLLITE, Hauy, Phillips, Sfc. ; Pyramidal Kuphon-spar, Mohs. Tetragonal, P 121 0' ; usual forms, P, ooPoo (m) and OP. The crys- Fig. 123. ta ^ s are e i tner pyramidal when P, or short prismatic when ooPco . OP, or tabular when OP predominates (fig. 123). They usually form druses, and sometimes lamellar aggregates. Cleavage, basal perfect ; prismatic along ooPoo imperfect. Brittle ; H. = 4'5 5 ; G. = 2'3 2-4. Transparent to translucent on the edges ; lustre vitreous ; on OP pearly. Colourless, but yellowish, greyish, or reddish-white, to rose or flesh-red. In closed tube yields much water, sometimes with traces of flu- orine. B.B. exfoliates, intumesces, and melts easily to a white enamel. Easily fusible in borax ; with salt of phosphorus leaves a siliceous skeleton. Before igni- tion, small fragments exfoliate in hydrochloric acid, and the powder is readily soluble, leaving slimy silica. Chem. com. 4 ca 2 si 3 + Ksi 3 -f- 16 H with 52'8 silica, 25*4 lime, 5*3 potash, and 16'5 water ; in some with a little fluorine. Analyses. Silica. Lime. Potash. Water. Flu- orine. Total. 1 51-85 25-22 5-31 16-91 99-30 Stromeyer, Disco. 9 51-86 25-20 5-14 16-04 98-24 Do. Fassa. s 52-38 24-98 5-37 16-20 0-64 a 99-57 Berzelius, Faroe. 4 52-13 24-71 16-20 082 a 99-13 Do. Uton. 5 6 52-13 51-33 24-43 25-86 4-90 16-20 1-54 1-28 9957 Do. by Rammelsberg. Bammelsberg, Andreasberg. 7 5020 24-52 .. 1-09 Do. Do. 8 52-44 24-61 4-75 16-73 1-436 99-96 Do. Radauthal, Harz. (a) Fluoric acid ; (&) fluosilicate = 0-46 fluorine. The amount of fluorine seems very variable, Eammelsberg having found it = 0*24 and 0*74 per cent., in two other trials on the mineral from Utoe. It is obtained as a fluosilicate, but R. considers this as a product of the analysis, and does not think that any fluoride (Flu- orur) is here united in determinate proportions with a silicate. His " hypothesis" is, that apophyllite is a double silicate of lime and pot- ash, in which the fluorine replaces a portion of the equally electrone- gative oxygen ; or that part of c a si is replaced by (Ca ri + Si n 3 ) and in like manner, part of k'si , by (K ri + Si n 3 ). Occurs chiefly in amygdaloid and other trap rocks, but also in beds of ore, or veins in primary and transition formations. Fine varieties are found at Utoe in Sweden, Aussig and other parts of Bohemia, the Seisser Alpe in Tyrol, St Andreasberg in the Hartz (red, and rarely asparagus-green, crystals at a great depth in the Samson's mine) ; also at Nertschinsk in Siberia, in Greenland, 3 OKENITE PECTOLITE. 169 Iceland, and Faroe. In Scotland, it occurs near Raith in Fife, in the cavities of fossil-shells in limestone. This species has been named Ichthyophthalm or fish-eye, from its characteristic pearly lustre. The Albin of Werner is a white opaque variety, from the Bohemian Mit- telgebirge. Sir D. Brewster found, in some specimens from Naalsoe in Faroe (No. 3.), a peculiar tessellated or mosaic-like structure, and distinguished them as Tesselite. The Oxhaverite of Brewster, from Iceland, seems only a mixture with hydrate of iron and alumina. 58. OKENITE, v. Kobell ; Dysclasite, Connel. Rhombic ; o>P 122 19' ; according to Breithaupt, the combina- tion ooP . ooPoo . OP ; but usually massive, with a fine columnar or fibrous texture. H. = 5 ; G. = 2-28 2-36. Transparent to trans- lucent on the edges. Slightly pearly. Colour yellowish to bluish- white. B.B. froths up and melts to an enamel. In powder easily soluble in hydrochloric acid, leaving gelatinous flakes ; after ignition is insoluble. Chem. com. 6a si 2 + 2 H = 57 silica, 26 lime, and 17 water. Analyses. Silica. Lime. Potash. Soda. Alumina. Iron perox. Mangan. perox. Water. Total. co to i-" 55-64 57-69 54 -88 26'59 26-83 26-15 trace. 0-*3 : 44 1-02 f o- : 46 > K 53 0-32 0-22 17-00 14-71 17-94 9976 100-44 100-45 v. Kobell. Connel. Wurth. Occurs in amygdaloid on Disco island (No. 1), and at Tupaursak in Greenland. Also in Faroe (No. 2), and Iceland (No. 3). 59. PECTOLITE, v. Kobell. Morioclinohedric ? but only in spheroidal, radiating columnar masses. Cleavage, prismatic along a slightly obtuse prism. H. = 5 ; G. = 2 -69 2 -74. Translucent on the edges- Lustre slightly pearly. Colour, greyish -white or yellowish. B.B. melts easily to a clear (or white enamel-like, v. Kobell) glass. Soluble in hydrochloric acid, leaving flaky silica ; after ignition gelatinizes perfectly. Chem. com. 8 ca si + Na 2 si 3 + 3 H = 52*1 silica, 34-2 lime. 9-5 soda with potash, and 4-2 water. Analyses. 1 2 a Silica. Lime. Potash. Soda. Alumina. Magnesia. Water. Total. 51-30 54-60 55-96 3377 .'tt-65 35-12 1-57 (Hill 8-26 6 : 75 0-90 a 0-50 a 0-08 c 6-80 3-89 3-20 6 0-16 99-K9 98-75 99-31 v. Kobell. Beck. Hayes. (a) With iron perox. ; (I) with carbonic acid ; (c) with magnesia + 0-64 mangan. protox. P 170 CHABASITE LEVYXE GMELINITE. [Zeolite Occurs at Monte Baldo in the Veronese (No. 1) in amygdaloid, and at Mount Monzoni in Tyrol. In that from the latter place Ber- zelius found a strong reaction of fluoric acid, and hence thinks the alumina in anal. No- 1 to be fluoride of calcium. Frankenheim conjoins it with hornblende, but this is opposed by its action with acids. The StelKte, from Bergenhill, N. J., is, according to Dana, si- milar in external characters, but its composition is doubtful (anal, Nos. 2 and 3). The Danburite of Shepard, from D anbury, Connecticut, transpa- rent, vitreous, and honey-yellow, with H. = 7-5, and G. = 2-83, should come here if a pure mineral. Shepard's analysis gave 56-00 silica, 28-33 lime, 1-70 alumina, 0'85 yttria? 5-12 potash (with soda?) and loss, and 8'00 water ; but Dana says it is a mechanical mixture of grains of quartz with a silicate of lime. 60. CHABASITE, Bosc d" 1 Antic, Jameson; Chabasie, Hauy, Phillips ; LEVYNE, Brewster ; GMELINITE, Brewster. Rhombohedric ; R 94 46' ; the fundamental form appears gene- rally alone, but also with R, 2R, and other subordinate forms. Intersecting macles are very common, with the twin axis the chief axis. The crystals generally collected in druses and striated Cleav- age, rhombohedric along R more or less perfect. H'. = 4 4-5 ; G. = 2 2'2. Transparent to translucent. Lustre vitreous. Co- lourless, but greyish, yellowish, reddish to flesh-red. Streak white. B.B. fuses to a finely porous enamel. Soluble in hydrochloric acid, some (chabasite) leaving slimy silica ; others (gmelinite) gelatinizing. Some authors separate the Gmelinite and Levyne on account of their crystallization, which is thus given by Naumann. Gmelinite or the Natron chabasite, R 86 33' (96 18', Breit.), P2 with polar edges 141 4', middle edges 83 36' : the most usual form is f P2 . OR . ooP2 (a twinform of f R, Breit.). The faces of the pyra- mid are striated parallel to their polar edges ; those of the prism hori- zontally (fig. 124). Levyne, R 79 29', the usual form being OR . R . |R, in thick Fig. 124. Fig. 125. tabular forms and perfect intersect- ing twins (fig. 125). In Phacolite, a variety of the last, R 94 0', the usual form f P2 . ooP2 . R . R, mostly in twins. All these forms may, however, as Tamnau and others have shown, be derived from the primary form of chabasite. Analyses, next page. Notwithstanding all these analyses, the composition of this mi- neral is still problematical. In most species, the oxygen of the Family.] CHABASITE. 171 Silica. Alu- mina. Lime. Soda. Pot- ash. Iron perox. Watr. Total. ' 1 50-65 17-90 937 1-70 19-90 99-52 Berzelius, Gustavsberg. 2 48-38 19-28 8-70 2-50 21-14 100-00 Arfvedson, Faroe. 3 4863 19-52 10-22 0-M 0-28 ... 20-70 99-91 Hoffmann, Fassa valley. 4 48-18 19-27 965 1-54 0.21 21 '10 9995 Do. Do. 5 51-46 17-65 8-91 1-09 0-17 0-85 19-66 99-79 Do. Parsborough, N. S. 6 48-36 7 48-76 8 50-14 18-62 17-44 17-48 9-73 10-47 8-47 0-23 2-56 1-55 2-58 ... 20-47 21-72 20-83 100 99-94 99-50 Rammelsberg, Aussig. Thomson, Kilmalcolm. Connel, Do. 9 49-20 17'91 9-64 1-92 20-41 99-08 Thomson, Do. 10 55-99 17-60 7-21 0-65 0-90 ... 17-65 100-00 Rammelsberg, Parsbor.,N.S. 11 48-00 20-00 8-35 2-86 0-41 ...a 19-30 99-32 Berzelius, Faroe. 12 46-30 22-47 9-72 1-55 1-26 (0-96)6 19-51 102-07 Connel, Skye. 13 45 63 19-48 13-30 1-68 1-31 0-43 17-98C 99-95 Anderson, Leipa. 14 46-20 22-30 10-34 T-77 19-OSd 100-00 Rammelsberg, Do. 15 46-46 21-45 10-45 0-95 1-29 19-40 100-00 Do. Do. 16 48-56 18-05 6-13 3-85 0-39 o'-'ii 21-66 98-75 Connel, Glenarm. 17 46-40 21-09 3-67 7-30 1-60 ... 20-41 100-47 Rammelsberg, Do. 18 46-56 20-19 3-90 7-09 1-87 20-41 100-02 Do. Do. J9 48-99 1977 4-07 6-07 0-40 20-70 100 Thomson, Portrush. 20 47.75 20-85 5-74 2-34 1-65 ... 21-30 99-63 Durocher, Faroe. (a) + 0-40 magnesia; (6) with manganese peroxide; (c) + 0*14 magnesia; (d) + 0'34 magnesia. alkaline bases (lime, soda, and potash) is to that of the alumina, the water, and the silica, as 1 : 3 : 6 : 8, whence Berzelius pro- posed the general formula (da 3 , Na 3 , k 3 )'si 2 + 3 A*I *sV 2 +- 18 H, (or RSi + AI si 3 + 6n), the lime and natron chabasites differing only in the proportion of these bases. Some (Nos. 1, 5, 11 above) con- tain more silica (as 1 : 3 : 6 : 9), and Eammelsberg proposes the in- quiry whether the mineral may not contain quartz. In others again, the proportion of alumina is greater, and of silica less (Nos. 12, 13, 14, 15,), and these Connel and Naumann separate as Levyne and Phacolite with the formula 2 A i si 2 + c'a 2 si 3 + 10 H = 47 '5 silica, 22'0 alumina, 10*8 lime (with soda and potash), and 19*7 water. No. 20, if correct, gives a still different atomic proportion. In con- nection with this diversity of chemical composition, it is remarkable that Sir D Brewster finds that different parts even of the same crystal of chabasite have distinct optical properties. Occurs chiefly in amygdaloid and other trap rocks ; also in lava, and more rarely in syenite, diorite, and the crystalline schists in me- talliferous beds or veins. The Chabasite (Nos. 1-10) occurs in large beautiful crystals in Faroe, Iceland, Greenland, and Aussig in Bohe- mia. Smaller crystals at the Giants' Causeway, Kilmalcolm in Ren- frewshire, in Skye, and other places in Scotland. The Levyne (Nos. 11, 12) in Faroe, Skye, Glenarm in Antrim, and Hartfield Moss in Ren- frewshire. The Phacolite (Nos. 13, 14, 15) at Leipa in Bohemia. The Gmelinite (Nos. 16, 17, 18, 19) at Glenarm, and as the so-called Sarcolite at Montecchio Maggiore, and Castel in the Vicentine. 172 FAUJASITE HARMOTOME. [Zeolite The Lederite of Jackson (No. 1 below) from Cape Blomidon, Nova Scotia, in splendent, colourless, and transparent hexagonal prisms, is probably a lime chabasite, the phosphoric acid arising, as Berzelius thinks, from a mixture of apatite. The Acadialite, (Nos. 2, 3, 4 below) also from Nova Scotia, of a wine-yellow or flesh-red colour, is also probably chabasite mixed like some of those above, with un- combined quartz. Silica. Alu- mina. Lime. Soda. Pot- ash. Iron perox Pospho- ric acid. Watr. Total. 1 2 3 49-47 52-4 5202 21-48 12-4 1788 11-48 116 4-24 3-94 4 : 6V 3-03 0-14 2-4 3-48 8-58 21-6 18-30 98-57 100-4 99-60 Hayes. Thomson. Hayes. 4 fi2-S 18-27 6-58 2-12 ... 20-52 99-69 Do. 61. FAUJASITE, Damour. Tetragonal, P 105 30', primary form alone known. Fracture un- even ; brittle. Scratches glass ; G. = 1 '923. Transparent. Lustre vitreous or adamantine. Colour white or brown. In closed tube yields much water. B.B. intumesces and fuses to a white enamel. Soluble in hydrochloric acid. Chem. com. jsi 3 + iisY 2 + H, where ii is lime and soda. Analysis. 1 Silica. Alumina. Lime. Soda. 4-34 Water. Total. 49-36 16-77 5-00 22-49 97-96 Damour. Occurs in an augitic amygdaloid on the Kaiserstuhl in the Breisgan in Baden. 62. HARMOTOME, Hauy, Phillips; Cross-stone, Jameson; Baryte- harmotome, Naumann ; Paratomous Kuphon-spar, Mohs. Fig. 126. Rhombic ; the polar edges of the pyramid P ac- cording to Kbhler, 1 20 1 ', and 121 27', those of the brachydome too 111 15' ; and hence ccP 88 44'. Usual combination ooPoo (g) . oePoo (o) . P . P , or short prismatic. Generally in perfectly inter- secting macles, the chief axes coinciding, and the macrodiagonal of the one corresponding to the brachydiagonal of the other (fig. 126). Cleavage, brachydiagonal imperfect but distinct; macro- diagonal less distinct. Brittle ; fracture uneven. H. = 4-5 : G. = 2-3 2'43. Translucent .; Family} HARMOTOME . PHILLIPSITE. 173 lustre vitreous. Colourless, but white, or rarely grey, yellow, brown, or red. In closed tube yields water. B.B. fuses rather difficultly but quietly to a clear glass. Soluble but not readily in hydrochloric acid, with deposition of silica. Chem. com. 4 AI si 3 + 3 Ba si 2 + 18k = 48-3 silica, 17'8 alumina, 19'9 baryta with lime and potash, and -14 water. Analyses. Silica. Alu- mina. Baryta. Lime. Pot- ash. Water. Total. 1 49 16 18 ... 15 98 Klaproth, Andreasberg. 2 44-79 19-28 17-59 l'-08 ...a 15-32 98-91 Wernekinck.Schiffenb. Giess. 3 46-P 83 30', o>P : OP 114. The crystals of the combination ooP. OP are prismatic, and either irregularly aggregated, or grouped in bundles. Also massive with a granular or columnar texture. Cleavage, prismatic along ooP very perfect ; basal imper- fect. Very friable. H. = 3 3'5 ; G. = 2-25. Translucent on the edges, but opaque when weathered. Lustre pearly. Yellowish- white. B.B. exfoliates, froths, and melts easily to a white enamel. In closed tube yields much water. Decomposes quickly in the air. Soluble in acids. Chem. com. c'a 3 si 4 + 4 Jii si 3 + 12 k = 55'5 silica, 23 alumina, 9*4 lime, and 12-1 water. Analyses. Silica. Alu- mina. Lime. Water. Total. 2 3 56-13 54-92 55-00 22-98 22-49 24-36 9-25 9-5 10-50 11-64 13-54 12-30 100 100-00 102-16 Delffs, Schemnitz. Ib. by Rammelsberg. Von Babo, Schemnitz. Found in clefts and druses in a trachytic rock at Schemnitz, Hun- gary, and formerly considered Laumonite, which it much resembles. In No. 1, the mineral was dried at 100, and No. 2 is the same ana- lysis with the water as when only dried in the air. 67. GLOTTALITE, Thomson. Tesseral, and ooOoo , crystals grouped in druses ; cleavage un- known. H. = 3 4 ; G. =2'18. Highly translucent, vitreous. Co- lourless or white. In closed tube yields water. B.B. melts with in- tumescence to a white enamel. Chem. com. 3 c'a si + /ii si + 8H. Analysis. Silica. Alu- mina. Lime. Iron per ox. Water. Total 1 37-01 16-31 23-93 0-50 21-25 99-00 Thomson. Occurs in greenstone probably near Port-Glasgow, on the Clyde (Glotta). 68. EDINGTONITE, Haidinger ; Pyramidal Brythyne-spar, Mohs. Tetragonal ; sphenoidal-hemihedric ; P 87 9', formed as a sphenoid (P), with polar edges 92 51' ; and P (ri) also as a sphenoid, with polar edges 129 8'. Usually these two sphenoids, in reversed position, Family.] POTASH -MICA. 177 are combined with ooP (m), giving the small crystal, fig. 127, a py- Fig. 127. ramidal aspect. Cleavage prismatic along ooP perfect. H. = 4 4'5; G. = 2.72-75. Semi- transparent or translucent. Lustre vitreous, but faces of P dull. Greyish-white. In closed tube yields water. B.B. fuses rather difficultly to a colourless glass. Chem. com. unknown. Analysis. Silica. Alu- mina. Lime. Water. Total. 1 35-09 27-69 12-68 13-32 8878 Turner. The quantity analysed was very small, and the loss probably soda or potash. Found with Thomsonite in the Kilpatrick Hills, Dumbar- tonshire, but very rare. VII. 69. POTASH-MICA, Glimmer, Werner (in part) ; Mica, Hauy, Phil- lips, 8fc. (in part) ; Hemiprismatic Talc-mica, Mohs, (in part). Monoclinohedric, but dimensions not accurately known. Crystals chiefly rhombic or six-sided tables (seldom prisms), with the side edges inclined to each other at 120 46' and 59 14', and to the ter- minal plane at 98 40' and 81 20' (G. Rose). The crystals are im- bedded, or attached in druses ; also massive and disseminated, or form scaly, foliated, or lamellar aggregates. Macles rather rare. Cleavage, basal highly perfect ; sectile, and in thin lamellse, elastic. H. = 2 3 ; G. = 2-8 8'1. Pellucid in various degrees ; trans- parent laminae optically binaxial. Lustre metallic-pearly, on some faces vitreous. Colourless, but coloured white, grey, green, red, brown, black, and rarely yellow. Often different tints in transmitted and reflected light. In closed tube usually yields water, with traces of fluorine. B.B. loses its transparency, and fuses more or less rea- dily to an obscure glass or white enamel. Not affected by hydro- chloric or sulphuric acids. In borax melts to a glass generally coloured by iron. Chem. com. very variable, but, according to L. Gmelin, on the whole nearly 3 AI si + K si 3 = 48 silica, 39'8 alu- mina, and 12 -2 potash ; part of the potash occasionally replaced by protoxide of iron or manganese, and of the alumina by the peroxide of these metals, or of chrome. Analyses, next page. 178 POTASH-MICA. {Mica Silica. Alu- mina. Iron perox. Man. perox. Mag- nesia. Pot. Soda. Lime. Flu. acid. Watr. Total. 1 4800 34-25 4-50 0-50 8-75 1-25 h 97-25 Klaproth. 2 47-50 37-20 320 0-9D M 9-60 5-56 2-63 101-59 H. Rose. 3 46 10 31-60 8-65 1-40 8-39 1-12 1-00 98-26 Do. 4 46.22 34-52 6-04 2-11 a m 8-22 1-09 0-986 98-18 Do. 5 46-36 36-80 4-53 0'002a M 9-22 M 0-77 184 99-52 Do. 6 47-19 33-80 4-47 2-58 a M 8-35 o-'is 0-29 4-07 100-88 Do. 7 36-54 25-47 27-06 1-92 5-48 .. 0-93 2-70 100-10 Turner. 8 47-97 9 39-45 31-69d 9-27 5-37 35-78 1-67 2-54 3 : 29 8-31 5-06 032e 0-3*1 0-72.9 0-29 g 3-32 1-83 99-40 99-587 Svanberg. Do. 10 41-30 15-35 1-77 2879 970 065/ 3-30 g 0-28 h 101-14 Meitzendorff 11 40-91 17-79 11-02 ... 19-04 9-96 0-30 99-0? Chodnew. 12 39-85 16-07 13-21 ... 15-60 13-68fc M 0-12 100-00 Varrentrapp 13 47-95 34-45 1-80 ... 0-72 10-75 037 0-42 I 0-35 g ... 100-76 Schaffhautl. 14 47-68 15 5020 15-15 35-90 5-72 2-36 1-17 11-58 7-27 1 17 845 ... i trace^ 2-86 2-45 98-511 Do. 99-36 Do. 16 47-31 ,5-74 28-91 0-48 10.17 1*05 ... 6-23 99-89 Mitscherlich (a) With magnesia ; (6) trace of titanic acid ; (c) protoxide ; (d) + 0'35 aluminium ; (e) calcium + 1-45 iron protoxide; (/) with a little lithia; (g) fluorine; (h) loss by heat; (i) + 5-91 chrome-oxide; (k) with soda and loss; (I) calcium, + 3-95 chrome-oxide. From(l) Siberia (silver-white); (2) Utoe; (3) Broddbo, near Fahlun; (4) Fahlun; (5) Kimito in Finnland; (6) Ochotzk; (7) Cornwall, brown ; (8) Broddbo; (9) Aborforss in Finnland; (10) Jefferson County, New York, brown ; B.B. melts easily to a white enamel, colouring the flame pale-red; (11) Vesuvius, blackish-green, part of the iron evidently protoxide; (12) Zillerthal; (13) Fuchsite, from Schwarzenstein in Zillerthal, emerald or dark-green colour ; (14) chrome mica, found with Nos. 1, 3 ; B.B. only fusible in very thin Jeaves ; almost wholly soluble in hydrochloric acid; (15) St Gotthardt These analyses show the very varied composition of this mineral. The fluorine found in many is often thought accidental, but H. Rose finds it most abundant in the best characterized varieties, as those from granite. He has found it in grey mica from Broddbo, Zinnwald, Altenberg, Murzinsk, Siberia ; in gold-yellow mica from Kimito, Bor- stils Sacken in Sweden, Utoe ; and in other specimens from Massa- chusetts, Russia, Pargas, and Sala. Those in which it is most abundant (the first 7 or 8) lose their colour and lustre on ignition ; the poorer varieties more or less retain them. He also shows that the fluorine increases or decreases with the proportion of iron. The variety (No 10 anal.) was determined to be diaxial by Dove, but contains a proportion of magnesia, formerly thought peculiar to the monoaxial micas. No. 11 was found by G- Rose to have a mo- noelinohedric crystallization, and therefore should be optically diax- ial, though this could not be ascertained ; whereas, in composition it resembles the monoaxial. No. 12 was likewise monoclinohedric, and No. 14 diaxial. Poggendorf also states that the magnesian-mica from lake Baikal (No. 1 below) was diaxial, and thus also anoma- lous. Hence the connection between the crystallographic, optical, and chemical characters of mica seems still uncertain. Mica is a very common mineral, and forms a considerable portion of the earth's crust. It enters as a primary constituent into granite, Family.'] LITHIA-MICA. 179 gneiss, mica-slate, and other crystalline rocks. Accidentally it is found in syenite, euphotide, hypersthene-rock, diorite, many porphy- ries, trachyte, and basalt. It also forms part of the sedimentary rocks produced from the destruction of these. More rarely it occurs in lava, or volcanic ejectamenta, in granular limestone, dolomite, magnetic iron-ore, iron-glance, iron-pyrites, copper-pyrites, and other ores. It usually appears in crystalline scales or leaves, lying parallel to the laminae of the slaty rocks ; but rarely, as in some chlorite slates, at right angles to the lamination. The largest mica plates occur in granite veins, as at Skutterud in Norway, Fiubo in Sweden, in Brazil, and especially in Siberia, where the plates, often a yard in diameter, and named Muscovy glass, are used for windows, but be- come white on exposure. Fine crystals are found at Vesuvius, the Ilmen mountains, St Gotthardt, Pargas, Arendal, and in Cornwall and Aberdeenshire. Spherically curved plates occur at Kimito in Finnland. According to Hauy, mica will divide into laminse one 250,000th of an inch thick, and it is thus well adapted for various optical purposes. Mica shows a great tendency to associate with quartz, and, in a less degree, with the felspathous minerals. It like- wise often occurs intimately united with andalusite, pinite, and tur- maline. It seems sometimes to form whole rocks, and some so-called talc slates, as that of St Gotthardt, in which the cyanite is found (Paragonite of Schaffhautl), seem merely this mineral, anal. No. 15. Mica is occasionally formed during metallurgic processes ; No. 16 being such an artificial mica from the copper furnaces of Garpenberg in Sweden. The sandstone forming the walls of iron furnaces is also often changed into a foliated pearly mineral very like mica, probably from the influence of the wood ashes. 70. LITHIA-MICA ; LEPIDOLITE, Werner, S$c. Synonyms as in last species. Monoclinohedric (or triclinohedric ?), but dimensions unknown. In crystallization and physical characters agrees with potash-mica, but colour often rose or peach-blossom red. In the closed tube shows evident fluorine reaction. B.B. melts very easily with effervescence to a colourless, brown, or rarely black magnetic glass, colouring the flame red (especially with fluor-spar or sulphate of potash). Imper- fectly soluble in acids, wholly so after fusion. Chem. com., accord- ing to L. Gmelin, generally 3 AI si 2 + 2 LI si 4- (KF, SiF 3 ), with 51'6 silica, 28*5 alumina, 8 1 7 potash, 5'3 lithia, and 5*9 fluoric acid ; but many contain much protoxide of iron and manganese, and some correspond better with 4 1 si 3 + KF 2 + 2 Li F ; others with .ai si 3 + RF. Analyses, next page. 180 MAGNESIA- MICA. \Miea Silica. Alu- mina. Mang. prot. Iron prot. Pot- ash. Lithia Soda. Fluor, acid. Watr. Total. 1 52-25 28-35 3-66 6-90 4-79 ... 5-07 trace 101.02 C. Gmelin. 2 49-06 33 -6 J 1-400 ... 4-19 3-59 0-416 3-45 4-18C 100 Do. 3 46-23 14-14 4-57 17'97a 4-90 4.21 ... 8-53 0-83 101-38 Do- 4 44-28 24-53 1-66 11-33 9-47 4-09 ... 5 14 100-50 Turner. 5 40-19 22-79 2-02 19-78 7-49 3-06 ... 3-99 99-25 Do. 6 50-82 21-33 trace 9-08 9-86 4-05 4-81 99-95 Do. 7 40-06 22-90 1-79 27'06a 4-30 2-00 ... 2-71 M lftO-82 Do. 8 50-35 28-30 1-23 9-04 5-49 ... 5-20 M 99-61 Do. 9 50-91 28-17 1-08 9'50 5-67 ... 4-11 99-44 Do. 10 4776 20-29 4-67 0-12d 10-96 277 2-23 10-22e 1 I6f 100-18 Rosales. 11 47-01 20-35 1-53 14'34a 9-62 433 0-40/ l-43e 153 100-54 Stein. 12 42-97 20-59 0'83a 14-18a 10-02 1-60 1-41(/ 6'35e 022 9838 Lohmeyer. (a) Peroxide; (6) magnesia; (c) with loss + 0-112 phosphoric acid; (d) lime; (e) fluo- rine; (/) chlorine; (g) + 0-21 chlorine. From (1) Penig in Saxony; (2) Rozena in Moravia; (3, 4) Zinnwald in Bohemia; (5) Altenberg; (6) Cornwall, grey; (7) do. brown; (8) Ural; (9) Utoe ; (10) Ural, mean of three (the silica probably too small, the alkalis and lithia metallic, and not the oxides) ; (11) Altenberg in Erzgebirge; (12) Zinnwald (same as Nos. 3, 4) ; B.B. melts to a black enamel. As above stated, this mineral also varies much in composition, and the formula is still uncertain. Its chief characteristic is the large amount of fluorine, and the presence of 2 6 per cent, lithia. The soda shown in the more recent analyses was probably left with this in the older ones. According to Fownes and Sullivan, it contains a large amount of phosphoric acid, already noticed by C. Gmelin (No. 2). The red varieties are said to contain only the peroxide of manganese, and not that of iron. Lepidolite occurs in granite, gneiss, and veins of quartz, though far less common than the potash- mica, with which it is probably often confounded. The crystallized varieties are chiefly from veins of tin ore in Bohemia, Saxony, and Cornwall. It is sometimes used as an ornamental stone. 71. MAGNESIA-MICA; BIOTITE, Hausmann; Mica, Phillips, Hauy, 8fc. (in part) ; Rhombohedral Talc-mica, Mohs. Hexagonal ; P 149, the crystals are mostly tabular from the pre- dominance of OP, rarely short prisms. It occurs imbedded, or attached and in druses ; also massive, forming laminar, scaly, or other aggre- gates. Cleavage, basal very perfect. Sectile, sometimes brittle, and in thin plates elastic. H. = 2'5 3 ; G. = 2*85 2*9. Transpa- rent, but often only in very thin plates, and then generally mono-axial. Lustre metallic pearly on OP. Usually dark-green, brown, or black, rarely other colours. Streak greenish-grey or white. B.B. difficultly fusible to a grey or black glass. In closed tube often yields water, with traces of fluorine. Scarcely affected by hydrochloric acid, but completely soluble in concentrated sulphuric acid, leaving white pearly plates of silica. Chem. com. very variable, but usually given as A! si 4- B 3 si 2 (the same with garnet), k being = Mg, k, Fe ; but L. Gmeliu Family, ,] LEPIDOMELANE. shows that some agree well with A*l si + 2 R s'i. Analyses. 181 si 3 , and others with Silica. Alu- mina. Iron perox. Iron protox. Mag- nesia. Potash. Fluoric acid. Water. Total. 1 42-01 16-05 4-93 25-97 7-55 0-68 97-19 H. Rose. 2 40-00 12-67 19-03 1 : 63 15-70 5-61 2-10 '.'.'. b 97-37 Do. 3 42-12 12-83 10-38 9-36 16-15 8-58 ... 1-07 100-49 v. Kobell. 4 41-00 16-88 4-50 5-05 18-86 8-76 trace. 4-30 99-35 Do. 5 40-00 16-16 7-50 0-20 a 21 54 10-83 0-53 3-00 99-76 Do. 6 3975 15-99 8-29 ... 24-49 8-78 ... 0-75 c 98-62 Bromeis. 7 42-59 21-68 10-39 10-27 8'45 0-51 d 3-35 e 98-81 S ,-anberg. 8 42-46 12-8 7 : 'n 25-39 6-03 0-62 d 3-17/ 99-16 Do. 9 44-41 16-86 20-71 11-26 4-05 0-41 d l-l3g 101-61 Do. 10 40-86 15-13 1300 22-00 883 ... 0-44 100-26 v. Kobell. (a) Titanic acid ; (Z>) + 0-63 peroxide of manganese ; (c) loss by heat + 0'87 lime,"and 0-10 undecomposed mineral; (d) fluorine; (e) +0'75 protoxide of manganese, 0'26 lime, and 0'56 calcium ; (/) + TOG manganese protoxide, 0-36 magnesium, and O'lO aluminium ; iff) + 0'46 manganese protoxide, 0'90 lime, and 0'43 calcium. From (1) Lake Baikal ; (2, 3) Miask ; (4) Karosulik, Greenland ; (5) Monroe, New York ; 16) Vesuvius; (7) Pargas; (8) Sala; (9) Rosendahl near Stockholm ; (10) Bodenmais, G. =2-7- These analyses seem incapable of being comprised under any com- mon formula. The chief characteristic is the large proportion of mag- nesia, ancb the smaller of alumina. As stated above, the optical cha- racters do not correspond with the chemical, and, were they neglected, Nos. 10, 11, 12, 14 of potash-mica should come under this species. This mineral seems far less common than potash-mica, from which, however, it has rarely been distinguished. It seldom forms an essential constituent of mountain rocks (Miascite of Ilmen), but is more often accidentally disseminated in them (chlorite slate of Ural, &c.), or in subordinate beds and veins. Remarkable varieties are found at Monroe in North America, Karosulik in Greenland, and in the ejected blocks on Vesuvius. The Rubellan of Breithaupt, brownish-red, hexagonal tables, found in Bohemia and Saxony in wacke and amygdaloid, seems this mineral. 72. LEPIDOMELANE, Hausmann. Hexagonal; in small six-sided tables seldom above half a line broad, forming a granular scaly aggregate. Cleavage, basal perfect. Rather brittle. H. = 3 ; G. = 3-0. Lustre vitreous, inclining to adamantine; colour raven-black ; streak mountain-green. Opaque, but very thin laminae translucent, with leek-green light. B.B. be- comes brown, and fuses to a black magnetic bead ; in borax forms a bottle-green glass. Soluble in hydrochloric or nitric acid, leaving pearly scales of silica. Chem. com. (i, re,) si + (FC, k,) si. Analysis, next page. 182 CHLORITOID CHLORITE. [Mica Silica. Alum. Iron per- oxide. Iron pro- toxide. Magnesia. Lime. 0.60 Potash. Watr. Total. 1 37.40 11.60 27.66 12.43 9.20 0.60 99.49 Soltmann. Probably from Persberg in Wermeland. The Raben-glimmer of Breithaupt seems the same mineral. 73. CHLORITOID, Breithaupt; Chlorite-spar, Fiedler, Mohs. Massive, in coarse granular aggregates, composed of curved folise. Cleavage in one direction perfect. Brittle. H. = 5.5 6 ; G. = 3.55. Opaque or translucent in thin laminae. Lustre weak pearly ; colour blackish-green ; streak greenish-white. B.B. is infusible, but becomes darker and magnetic. Not aifected by acids. Chem. com. i 2 si + Fe 2 si, with 26-2 silica, 43*4 alumina, and 30'4 iron protoxide. Analyses. Silica. Alumin. Iron protox. Mang. protox. Magnes. Water. Total. 1 24-90 2 24-96 3 24-40 4 27-48 5 24-1 C 33-20 46-20 43-83 45-17 35-57 43-2 29-00 28-89 31-21 30-29 27-05 23-8 25-93 V 30 6*00 4-29 0-24 6 : 95 7'6a 5-60 99-99 100-00 99-86 101-64 98-7 96.97 Erdmann, Ural. Do. Gerathewohl, Do. Bonsdorff, Do. Delesse, St Marcel. Jackson, Rhode Island. (a) + traces of titanic acid. The chloritoid occurs in chlorite slate at Kosoibrod near Katha- rinenburg in the Ural along with diaspore. Most specimens yield water in the closed tube, and G. Kose thinks Bonsdorff's analysis (No. 4) gives the true constitution. It would then agree with the Sismondim of Delesse from St Marcel in Piemont (No. 5), which is similar in external characters, and only differs in containing water. Dana thinks the Masonite of Jackson (No. 6) from Natic village, Rhode Island, nearly allied, but the purity of the specimen analysed is doubtful. In No. 3 the mineral was digested in diluted hydrochloric acid, and then dried at 212 F. 74. CHLORITE, Werner, Phillips ; Talc, Hauy, (in part) ; Ripidolite, G. Rose, Rammelsberg; Prismatic Talc-mica, Mohs, (in part). Hexagonal; P 120, v. Kobell (106 50' Descloizeaux). The crystals tabular of OP . ooP or OP . P (fig. 128), but often united in Fig 128 co^-tike or otner groups. Generally massive, and scaly, or imbedded in other minerals. Cleavage, basal perfect; laminae flexible, but not elastic. H. = 1 1-5 ; G. = 2-78 2'96. Thin plates trans- parent or translucent. Lustre pearly; colour, leek, celadine, pistacio or blackish-green ; the crystals often red transverse to Family.] RIPIDOUTE. 183 the chief axis. Streak green or greenish -grey. In the closed tube yields water. B.B. difficultly fusible on thin edges; so- luble in concentrated sulphuric acid. Chem. com. 2R si 4- a 2 AI + 3 H , or when 4 R = 3 M g + Fe, = 26-3 sil., 21-8 al., 25'5 mag., 15.0 Fe, and 11-5 watr. = 2Mg + 2F, = 24-6 ... 20-1... 15-9 ... 28-5 ... 10-9 ... but the analyses are variable, and part of the iron probably the per- oxide. Analyses. Si- lica. Alu- mina Mag- j Iron Mang, nesia. protox Prot. Water. Total. 1 26-51 21-81 22-83 15-00 12-00 98-15 v. Kobell, Greiner, Zillerthal. 2 27.32'20-69 24-89 1 15-23 6.47 12-00 100-60 Do. Schwazenstein, Do 3 26.06'l8-47 14-69 i 26.87 0-62 10-45a 99-40 Do. Rauris. 4 25-37 5 26-88 6 27-14 7 31-54 18-50 17-52 19-19 5-44 17-09 13-84 16-78 41.54 28-79 29-76 24-76 10-186 8-96 11-33 11-50 9-32 98-71 99-33 99-37 98-02 Varrentrapp n St Gotthardt. Marignac, St Chri stopher. Do. Mont des Sept -Lacs . Varrentrapp, Pfitsch, Tyrol. 8 30-2 13-2 379 3-lb M 17-0 101-4 Giwartowsky. 9 25-6022-21 30-96 5-00& ... 13-43C 99-45 Hermann. (a) + 2-24 remainder ; (b) peroxide ; (c) + 2-25 undecomposed matter and magnetic iron, 1-4, Foliated chlorite; 5, 6, scaly from the granite of Dauphine" ; 7, chlorite slate; 8, 9, steatite. Chlorite is one of the most widely-dispersed and geologically-im- portant minerals. Externally it resembles mica, and is frequently associated with, or replaces it, in granite, gneiss, and similar rocks. It is a component of the diabase porphyries and amygdaloids, and then often crystallized ; and is occasionally found in diorite, euphotide, and serpentine ; more rarely in greenstone porphyry, amygdaloid, basalt, and trachyte. It is most abundant in chlorite slate or in beds of pot-stone, intimately mixed with talc, for which it shows a strong affinity. From these it has passed into various sedimentary rocks, which owe to it their green colour. It is also common in beds or veins of ore, as of magnetic iron, in dolomite and marble, and is frequently associated with the almandine garnet, tremolite, schorl, and rutile. The Alps, Scandinavia, the Ural, the Harz, and many parts of Scotland, are well known localities of chlorite, both in its crystal- lized variety and as a constituent of rocks. Chlorite slate (No. 7) differs considerably in composition from the simple mineral. Some steatites seem only decomposed chlorite, as those from Snarum (No. 8), and the greenish variety (No. 9) from near Miask. 75. RIPIDOLITE, von Kobell, Hausmann ; Chlorite, G. Rose, Rammelsberg. Rhombohedric ; R : OR = 104 15'; crystals chiefly tabular and often in comb-like or fan-shaped groups. Cleavage, basal very per- fect. Sectile and flexible, but not elastic ; H. = 2 3 ; G. * 2-61 184 TALK. [Mica 2*77. Translucent, or in thin leaves transparent. Lustre pearly. Colour green, but red by light transmitted transverse to the axis. Streak colourless. B.B. exfoliates, becomes white, and fuses on the edges to a white enamel. Completely soluble in warm sulphuric acid. Chem. com. 3 Mg si + Mg 2 A! + 4 H = 33 '2 silica, 18'3 alu- mina, 35-7 magnesia, and 13'8 water; or 5 Mg-'si + M g 3 Ai 2 + 6 H = 32-9 silica, 21 '8 alumina, 33-9 magnesia, and 11*4 water. The iron is either the peroxide replacing alumina, or more probably, in part at least, the protoxide replacing magnesia, when the first for- mula is the more correct. Analyses. Silica. Alu- mina. Mag- nesia. Iron protox. Manga, protox. Water. Total. 1 32-68 14-57 33-11 5-97 0-28 12-10a 99-73 v. Kobell, Schwarzenstein. 2 31-14 17-14 34-40 3-85 0-53 12-20a 100-11 Do. Achmatowsk. 3 30-38 16-97 33-97 4-37 ... 12-63 98-31 Varrentrapp, Do. 4 31-47 16-67 32-56 5-97 o-oi 12-43 99-11 Bruel, Zillerthal. 5 32 1 18'5 367 0-6 12-1 100 Delesse, Maultjon. 6 30-01 19-11 33-15 4-816 12-52 99-60 Marignac, Alathal. 7 30-27 19-89 33-13 4-426 12-54 100-25 Do. Slatoust. 8 30-80 17-27 37-08 1-376 12-30 98-82 Hermann, Ural. 9 33-45 9-50 32-67 11-33 12-04 98-99 Schweitzer, Zermatt, Valais. 10 33-37 13-33 34-39 5-836 (0-T8)c 12-77 99-88 Marignac, Do. Do. 11 33-95 13-46 33-71 6-126 (0-24)c 12-52 100 Do. Binnen, Do. 12 34-23 16-31 35-36 3-336 175d 8-6 99-66 Komonen, Slatoust. 13 3235 18-00 32-29 4-37 12-50 99-51 Hermann, Do. (a) In No. 1 + 1-02, in No. 2 + 0'85 undecomposed matter; (6) peroxide; (c) chrome oxide; (d) lime. Nos. 1-8 are the ripidolite, Nos. 9, 10, 11 the pennine of Frb'bel from the Valais, which agrees so closely with ripidolite as to justify Rammelsberg in combining them. It crystallizes in acute rhombo- hedrons (R 63 15') generally so much truncated by OR as to become tabular. It is leek, bluish, or blackish-green, with a hyacinth red or brown tint across the axis, and a distinguished dichroism. In hydro- chloric acid it forms a green solution, the silica separating in scales. Ripidolite is known only from a few localities, but in many is pro- bably confounded with chlorite, from which it has only recently been disjoined. The finest crystals occur in druses often with garnets and diopside. No. 8 above is a silver-white crystallized variety, G. = 2-603, found in fissures in chrome iron ore near the Balschoi Iremel river, near Slatoust. Besides the above places, Reichenstein in Si- lesia, and Arendal, furnish fine varieties. Nos. 12, 13, the Leuchtenbergite of Komonen, of a yellowish-white colour, is shown by Hermann's analysis to be only ripidolite, perhaps partially decomposed. 76. TALK, Werner, Hauy, Phillips, fyc. ; Prismatic Talc-mica, Mohs (in part). Rhombic or monoclinohedric. Rarely found in six-sided or rhom* 3 TALK. 185 bic tables, not admitting of measurement. Generally massive in curved foliae, or granular, scaly aggregates ; also slaty or earthy. Cleavage, basal veiy perfect. Soft, sectile, and flexible in thin plates. H. = 1 ; G. = 2'68 275. Transparent in thin plates, and opti- cally diaxial. Lustre pearly or resinous. Colourless, but generally greenish or yellowish-white, to apple, leek, or olive-green. Feels very greasy. B.B. emits a bright light, exfoliates, and hardens, but is infusible. With salt of phosphorus, yields a silica skeleton ; with solution of cobalt, becomes pale red. Not soluble in hydrochloric or sulphuric acid before or after ignition, Chem. com. M g si 7 = 64 '4 silica, and 35'6 magnesia } or M g 7 si 8 = 63'9 silica, and 36'1 magne- sia ; but a part of the latter often replaced by iron-protoxide. The water in some is probably incidental. Analyses. Silica. Mag- nesia. Iron protox. Alu- mina Watr. Total. 1 58-2 32-2 4-6 M 3-5 99-5 Berthier, St Bernhaxd. 2 55-6 19-7 117 17 2-6a 99-4 Do. St Foix. 3 62-8 32-4 1-6 1-0 2-36 lOirl v. Kobell, Greiner. 4 62-80 31-92 1-10 0-60 1-926 98-34 Do. Katharinenburg. 5 63-0 33-<> trace 3-4 100-0 Delesse, Zillerthal. 6 62-30 3.V44 2-02 0-04 100-0 Marignac (m. of 2), Chamouni. 7 63-95 28"2. r > 0-60e 078 2-?lc 100-23 Tengstrom, Ingeris, near Abo. 8 6670 30-L'3 2-41 ... ... 99-34 Lychnell, Mont Cannegou. 9 63-13 34-30 2-27 ... ... 99-70 Do. Sala. JO 64 53 27-70 6-85 99-08 Do. Scotland. 11 66-53 33-42 trace 99-53 Do. China. 12 59.5 30-5 2-5 5-5 98-0 Klaproth, Wunsiedel. 13 65-64 30-80 3-61 ... ... 100-05 Lychnell, Do. 14 61-25 26-25 1-OOe 1-00 6-00/ 96-25 Vauquelin, Briancon chalk. 15 66-02 31-94 0'81 0-20d 99-72 Kersten, near Voightsberg. fa > + 8-1 lime; (6) loss by heat ; (c) + 3-94 volatile ; (d) loss by heat + 075 soda and pot- ash, with traces of chloride of sodium and sulphate of lime ; (e) peroxide ; (/) + 075 lime. Talk, Nos. 1-6, and steatite (Speckstein), Werner, &c., Nos. 7-15, are, according to Lychnell's analyses, which show the latter to con- tain no water, only different forms of one mineral. The steatite is massive, of grey, red, yellow, or green colours. B.B. melts in fine splinters to a white enamel, but in other respects acts like talk. Some steatites are decomposed chlorite or other minerals, and though simi- lar externally, are yet chemically distinct. Talc not only forms talc-slate, but enters with quartz, mica, chlo- rite, and felspar into the composition of many other crystalline rocks. It is also common in subordinate beds, often containing cyanite and staurolite ; or in veins, as of magnetic iron, copper pyrites, galena, and other ores, or is imbedded in limestone. Beautiful varieties occur at Greiner in Tyrol ; Sala, Fahlun, and other places in Sweden ; in the Pyrenees and many parts of the United States. Fine apple- green talc is found in Unst, one of the Shetlands ; and talc-slate is Q 186 8CHILLERSPAR. [Mica abundant in the Scottish Highlands. Steatite is a frequent pseudo- morph after quartz or calc-spar, and is common in veins, as of tin ore at Schlaggenwald in Bohemia ; in serpentine rocks, as at Gb'p- fersgrun in Baireuth, and the Lizard Point, Cornwall ; and in lime- stone, with fragments of encrinites, at Chapel Quarry, near Kirkcaldy, Scotland. Common talc is used as crayons for many purposes ; also for polishing stones, and for forming crucibles and porcelain. Talc- slate is employed as a lining for ovens ; and savage nations cut the steatite into culinary utensils. Potstone or Topfstein is an uncertain mixture of talc, chlorite, mica, asbestus, and other minerals, and occurs in beds in various countries among crystalline rocks. 77. SCHILLERSPAR, Jameson, Phillips; Schillerstein, Werner; Diatomous Schiller-spar, Mohs. Mono or tri-clinohedric, but only found granular and massive. Cleavage, very perfect in one direction, imperfect in another, meeting at 135-140. Fracture uneven, splintery ; H. = 3 -5 4; G. = 2-6 2 '8. Translucent on thin edges. Lustre metallic pearly. Colour olive or pistacio green, yellow, brown, or black. Streak greenish-white. Imperfectly soluble in hydrochloric, wholly in sul- phuric acid. B.B. becomes magnetic, and fuses in thin splinters on the edges. With borax fuses with difficulty to a glass, showing traces of iron when hot, of chrome when cold. Chem. com. perhaps 3 R 4 si 2 + a si 2 + 10H. Analyses. Silica. Mag- nesia. Lime. Iron protox. 13-02a 10-92 13-27a 16-61 Mang. protx. Chrm. oxide. Alu- mina. Watr. Total. 1 43-90 2 43-07 3 42-36 4 41-48 25-86 2616 28-90 27-24 2-64 2-75 0-63 0-53 0-57 0-85 2-37 1-28 1-73 2-18 6-49 12-43 12-43 12-07 10-13 99-66 100 100-26 101-95 Kohler, Baste. Do. Do. Do. Do. Rammelsb., Radauthal. (a) With chrome oxide. In the formula given above, the iron is considered partly as the protoxide (with magnesia and lime = R), partly the peroxide (with alumina and chrome-oxide = R). Rammelsberg deducts the chrome- oxide, alumina, and part of the iron as a mixture. The analyses distinguish it from hornblende and diallage, which it much resembles. The foliated variety, Nos. 1, 2, occurs in a compact rock, named schillerstein, of similar composition, No. 3 (not serpentine), found sparingly in the euphotide of the Harz, near Baste. No. 4 is a simi- lar mineral from the Radauthal in the Harz. Other localities, named for this mineral, in Europe and North America, are still uncertain. The true Metaxite of Breithaupt, from the Zweigler mine near Family. .] ANTIGORITE HYDROPHITE SERPENTINE. 187 Schwarzenberg, is closely related. It is massive, asbestiform, weak pearly lustre, and greenish-white colour. H. = 2 2*5 nearly ; G. = 2-52. Plattner found in it 43'60 silica, 34'24 magnesia, 6'10 alumina, 2-80 iron peroxide, and 12-67 water (= 99'41). In the closed tube it yields water ; and B.B. fuses difficultly on thin edges to a brown enamel. In hydrochloric acid is wholly decomposed, leaving silica in powder. 78. ANTIGORITE, Schweizer. Occurs in very thin, straight, slaty laminae, which separate rea- dily. H. = 2 -5 ; G. = 2 '62. Transparent or translucent ; lustre weak ; colour blackish -green in reflected, leek-green in transmitted light ; in some parts with brown spots. Streak white. In closed tube gives water. B.B. on very thin edges fuses to a yellowish-brown enamel. After strong ignition becomes silvery white, with weak me- tallic lustre. Difficultly soluble in concentrated hydrochloric acid, leaving flakes of silica. Chem. com. R 4 si 3 + H, where R is magnesia and iron protoxide, but probably better 3 R s + Mg H . Analyses. Silica. Iron prot. Mag- nesia. Alu- mina. Watr, Total. 1 46-22 2 46-18 13-05 1268 34-39 35-19 208 1-89 3-70 3-70 99-44 99-64 Schweitzer. Do. Probably from the Antigorio valley near Domo d'Ossola in Pie- mont. 79. HYDROPHITE, Svanberg. Massive, with a fine columnar or fibrous structure. Fracture un- even. H. = 3 4 ; G. = 2-65. Colour mountain-green. Streak lighter. In closed tube yields water. B.B. infusible, but shows reaction for vanadic acid. Chem. com. nearly (Mg Fe) 4 s\ 3 + 4 H. Analysis. -Js Mang. prot. Mag- nesia. Alu- mina. Vanadic acid. Water Total. 1 36-19 1 22-73 1-66 21-08 2-89 0-12 16-08 100-75 Svanberg. Found in the magnetic iron ore of the Taberg, Sweden. 80. SERPENTINE, Werner, Hauy, Jameson, Phillips, -c. ; Ophite, von Leonhard; Prismatic Serpentine-steatite, Mohs. Crystallization uncertain; though Haidinger describes some im- perfect rhombic forms, and others have been noticed by Beck hi 188 SERPENTINE. [Mica New York. Generally massive, and indistinctly granular or fibrous. Occurs in veins or imbedded masses, or as a pseudomorph after chrysolite, augite, &c. Fracture flat-conehoidal, uneven, or splin- tery. Sectile and slightly brittle. H. = 3 3*5 ; G. = 2*5 - 2-6. Translucent to opaque. Lustre dull. Colour various shades, generally dark, of green, grey, yellow, red, or brown, often in spots, stripes, or veins. Streak white, shining. Feels greasy. In the closed tube yields water' and becomes black. B.B. becomes white, and fuses with much difficulty on thin edges. With borax forms a green glass, and with salt of phosphorus leaves silica. With solu- tion of cobalt becomes pale-red. Soluble in hydrochloric, or better in sulphuric acid. Chem. com. Mg 3 si 2 -f 2 H = 44-02 silica, 43-11 magnesia, and 12-87 water, part of the magnesia being replaced by iron protoxide. Analyses. . Silica. Mag- nesia. Iron prot. Alu- mina. Water. Garb, acid and Bitumen. Total. 1 4167 41-25 1-64 13-80 137 99-73 Lychnell, Hoboken. 2 41-66 .37-16 4-05 ... 14.72 ...a 99-84 Stromeyer, Philipstad.* 3 42-97 41-66 2-486 0-87 12-02c 100 Hartwall, Snarum. 4 4071 41-48 2-43 2-39 12-61 9962 Scheerer, Do. 5 42.34 44-20 12-38 : 89cf 9981 Mossander, Gullsjo. f 40-98 33'44 8-72 073 1286 1-73 98-46 Lychnell, Taberg. 7 42.16 42-26 1-98 12-23 1-03 99-66 Do, Sala. 8 43-20 40-09 5-24 11-42 99-95 Do. Massachusetts. 9 4373 37-72 6-11 081 11-63 100 Schaffgotsch, Gornoschit, Ural, 10 40-52 42.05 3-01 0-21 13-85 6 : 30e 99-94 Marchand, Fahlun. 11 40-80 40-50 220 3-02 12-02 / 97-16 Ivanoff, Ural. 12 41-50 13 43-79 40-34 41-03 4-10 2-05 12-87 12-47 -9 99-73 9934 Kersten, Schwarzenberg.f Kammelsberg, Texas.:): (a) + 2.25 manganese peroxide; (6) peroxide; (c) with carbonic acid; (d) carb. acid; (e) carbonaceous matter ; (/) + 0-20 manganese protoxide, and 0-42 lime; (g) + 0.50 man. ganese protoxide, and 0'42 soda. * In Wermeland. f In Saxony, j In Lancaster County, Pennsylvania. There are very many other analyses of this mineral which may be found in Rammelsberg. That chemist has selected the above on which to base a formula, and finds the average oxygen in M g + F C : si (+ jai) : H to be as 9'2 : 12 : 6*1, or 3 : 4 : 2, which gives the above simple formula. Some contain a small proportion of chrome - oxide, 2'00 in one from Vermont, Jackson ; and a bright yellow ser- o pen tine from Asen, 2 '24 of cerium-protoxide, Lychnell. The supposed crystals of this mineral are not improbably merely pseudomorphs, as those from Snarum in Norway of olivine. Several varieties of it have been distinguished. 1st, Noble Serpentine, gene- rally with smooth conchoidal fracture ; translucent ; lustre dull, but resinous when polished ; and sulphur-yellow, siskin, leek or moun- tain-green, or greenish and yellowish-white colours (analyses Nos. Family.'} CHRYSOTILE PICROSMINE. 3, 10). 2d, Marraolite or foliated serpentine, of pale-green, yellow, or grey colours, with, it is said, a raonoclinohedric cleavage in two oblique planes (analysis No. 1). 3d, Picrolite or fibrous serpentine, translucent only on the edges, harder than noble serpentine (H. = 3-5 4'5), and of dirty-leek or mountain-green, more rarely brown colours (anal. 2, 6). 4th, Common or compact serpentine, dark- coloured, opaque, with a dull splintery fracture. 5th, Chrysotile of von Kobell (Baltimorite, Thomson ; Metaxite, De- lesse and Kiihn), in fine parallel asbestiform fibres, easily separated with olive or oil green, yellow brownish colours, and a metallic or silky lustre. Delesse considers it a distinct mineral, identical with serpen- tine in composition, but distinguished by its form and lower specific gravity = 2-219. Analyses. Silica. Mag- ne.iia. Iron protox. Alu- mina. Watr. Total. 1 2 43-5U 40-95 40-00 34-70 2-08 10-05 040 1-50 13-80 12-60 99-78 99-80 v. Kobell, Re : chenstein. Thomson, Baltimore. 3 42-1 41-9 3-0 0-4 13-6 100 Delesse, Reichenstein. 4 44-48 40-60 2-34 12-35 99-77 Kiihn, Do. Common serpentine alone, or more or less intimately mixed with euphotide, diabase, crystalline limestone, and dolomite, forms whole mountains. It occurs in many countries, as at the Lizard Point in Cornwall, in Shetland, and the Highlands of Scotland. Noble ser- pentine and picrolite form nests or veins in common serpentine, in granular limestone, or in magnetic iron, copper pyrites, and other ores. They are common in Norway, Sweden, North America, and at Portsoy in Scotland. The chrysotile was first known from Keich- eustein in Silesia (schillernderAsbest), but since in the Vosges Moun- tains and North America. Serpentine rock contains many minerals, as the pyrope, bronzite, diallage, bracite, and especially metals or ores, as platinum, chrome ore, arsenical pyrites, and magnetic iron ore. Serpentine is often cut into various ornamental articles, as it can be readily wrought on the lathe. It was formerly exported from Portsoy for such purposes. The rock is very durable unless when mixed with iron pyrites. 81. PICROSMINE, Haidinger ; Prismatic Picrosmine- steatite, Mofis. Rhombic, but only massive, in granular or columnar aggregates. Cleavage, brachydiagonal perfect, macrodiagonal less perfect, pris- matic along ooP 126 52', and macrodomatic along Poo 117 49' imperfect. Very sectile ; H. = 2*5 3 ; G. = 2*5 2'7. Trans- lucent on the edges or opaque. Vitreous, but pearly on ooPco . 190 V1LLARSITE. [Mica Greenish-white or grey, mountain, olive, or blackish-green. Streak colourless. Yields a bitter odour when breathed on (hence the name). In closed tube gives water and blackens. B. B. becomes white, opaque, and hard (= 5). Fusible with borax, and in salt of phos- phorus leaving a siliceous skeleton ; in cobalt solution becomes slightly red. Chem. com. 2 M g si + H 62 silica, 40 magnesia, and 9 water. Analyses. Silica. Mag- nesia. Alu- mina. Iron perox. Mang. pro- toxide. Water. Lime. Total. 98-15 100-40 98-48 1 54-89 2 5G-17 3 49-80 33-35 31-53 30'iO 0-79 Ml 1-40 8-56 b 6-866 0-42 trace 7-30 a 4-04 9-83 078 Magnus, Presnitz. A. Erdmann, Bergenstift. Svanberg, Sala. (a) With a little ammonia ; (b) protoxide. Picrosmine (No. 1) is found with magnetic iron in a bed in gneiss in the Engelburg near Presnitz, Bohemia. Also at the Greiner in Tyrol, in talc or chlorite slate ; and near Waldheim in Saxony, as veins in serpentine. Monradite of Erdmann (No. 2), from Norway, massive, foliated, translucent, and yellowish-grey. H. = 6 ; G. = 3 '267, has nearly the same composition, but with half the water, or 3 (Mg, Fe) si + H. B.B. is infusible, but becomes darker. The Picrophyll of Svanberg (No. 3), in dark-green foliated masses, with G. = 2-73 ; H. = 2-5. B.B. infusible, but becoming white, is also nearly related. Chem. com. 3 Mg si + 2 H. 82. VILLARSITE, Dufrenoy. Rhombic ; crystals formed by o>P . P . . OP, with ooP = 119 59' (?). Also massive and granular. Fracture uneven ; H.= 3 ; G. = 2'9 3. Translucent ; greenish or greyish-yellow. B.B. infusible alone ; with borax forms a green enamel. Decomposed by strong acids. Chem. com. 2Mg 2 si + H with 41 silica, 53 magnesia, and 6 water. Ana- Silica. Mag- nesia. Iron protox. Mangan. protox. Lime. Pot- ash. Watr. Total. 1 2 39-40 39-61 45-33 47-37 4-30 3-59 2-86 2-42 0-54 0-53 0-46 0-46 5-80 5-80 .98-69 99-78 Dufre'noy. Do. Chemically this mineral is a hydrous olivine, but in other charac- ters resembles serpentine. The crystallized serpentine from Pennig, described by Haidinger, had nearly the same angles, and probably Family,'] SPADAITE GYMNITE CHONIKRITE. 191 was this mineral. It occurs in beds of magnetic iron ore atTTraver- sella in Piemont. 83. SPADAITE, v. Kobell. Cryptocrystalline or amorphous ; only found massive, with an im- perfect conchoidal and splintery fracture. Sectile. H. =2'5. Trans- lucent ; weak resinous lustre ; colour red ; streak white. In closed tube yields water, and becomes grey. B.B. fuses to an enamel-like glass. Easily soluble in concentrated hydrochloric acid, leaving slimy silica. Chem. com. Mg 5 si 6 + 4n, with 57 silica, 32 magnesia, and 11 water. Analyses. 1 Silica. Mag- nesia. Iron protox. Alu- mina. Watr. Total. 5600 3067 0-66 0-66 11-34 99-33 v. Kobell. Occurs at Capo di Bove, near Rome. 84. GYMNITE, Thomson. Only found massive ; softer than felspar ; G-. = 2-216. Semi- translucent ; lustre resinous ; colour pale or dirty orange-yellow. B.B. emits water, and becomes dark-brown. With solution of cobalt rose -red ; with borax fuses to a colourless glass. Chem. com. Mg 4 si 3 + 6k = 41 silica, 36 magnesia, and 23 water. Analysis. 1 Silica. "'Mag- nesia. Alu- mina. Lime. Watr. Total. 40-16 36-00 1-16 0-80 21-60 99-72 Thomson. Named from the Bare Hills, near Baltimore, where it is found. The alumina showed traces of iron. 85. CHONIKRITE, v. Kobell. Massive. Fracture uneven. Sectile. H. = 2'5 3; G. = 2'91. Translucent or only on the edges. Lustre dull or glimmering. Co- lour snow, yellowish, or greyish white. In closed tube yields water. B.B. melts with ebullition to a greyish-white glass. With solution of cobalt blue. Soluble with deposition of silica in hydrochloric acid. Chem. com. 5 (M S , ca, p e ) 2 si + 2 A! si + 6 H. Analysis. Silic mlna'. Mag- nesia. Lime. Iron prot. Watr. Total. 1 35-69 j 17-12 22-50 | 12-60 1-46 9-00 98-37 192 PYROSKLERITE KAMMERERITE. [Mica Occurs on Elba in veins of serpentine ; but is perhaps, as Berzelius conjectured, a mixture. 86. PYKOSKLERITE, v. Kobell. Rhombic ? but only massive, with cleavage, in two directions at right angles, the one perfect, the other imperfect. Fracture uneven splintery. Sectile. H. = 3 ; G. = 2-7 2-8. Translucent ; lustre dull, or on the cleavage planes weak pearly. Colour apple, emerald, or greyish-green. Yields water in closed tube. B.B. fuses with dif- ficulty to a grey glass. With borax forms a chrome-green glass. The powder soluble in concentrated hydrochloric acid, leaving silica. Chem. com. 3 M g 2 si + ii'si + 4 H. Analyses. 7 H~ Alu- mina. Iron prot. Chrome oxide. .Water. Total. 37-03 31 -!)2 35-28 35-35 13-50 1373 3-52 179 1-43 11-00 T-33a 98-10 99-76 v. Kobell. Lychnell. (a) + 6-28 bitumen and carbonic acid. No. 1 is the pyrosklerite found with chonikrite in Elba. No. 2 is a greyish-yellow serpentine from Aker in Sodermanland, G- =* 2'605, which v. Kobell and Berzelius unite with this mineral. Scheerer would conjoin pyrosklerite with chonikrite. 87. KAMMERERITE, v. Worth. Hexagonal; OP . ooP tabular and prismatic ; but usually massive and granularly foliated. Cleavage, basal perfect. Sectile, flexible. H. = 1*5 2 ; G. = 2-76. Translucent ; lustre pearly. Colour violet-blue, reddish, or greenish. Feels greasy. In the closed tube gives water. B.B. exfoliates without fusing. With salt of phos- phorus leaves silica, and forms a glass brown when hot, and green when cold. Cobalt solution colours it partly blue. Chem. com. iden- tical with pyrosklerite, except one atom more water (5 H). Analysis. Silica. Alu- mina. Chrome oxide. Mag- nesia. Lime. Iron prot. Watt. Total. 37-0 14-2 1-0 31-5 1-5 1-5 13-0 997 Hartwall. Occurs with chromate of iron at Bissersk in Siberia. Though agreeing so nearly in chemical composition with pyrosklerite, it dif- fers much externally, and more resembles the hydrargillite. The Rhodochrome of Fiedler agrees closely with kammererite. It is massive, fine scaly, with a splintery fracture. H. = 2'5 3 ; G. = 2-668. Colour greenish -black, in fine splinters peach-blossom red. B.B. gives out water, and melts on thin edges to a yellow enamel. Family.'] PYROSMALITE. CRONSTEDTITE. 193 With borax forms a green glass. Difficultly soluble in hydrochlroic acid. Chem. com. silica, magnesia, chrome oxide, with a little alumina and water. Occurs on the island Tino in Greece, Kyschtimsk in Ural, Kraul in Styria, and near Baltimore, along with chromate of iron. 88. PYROSMALITE, Hausmann, Phillips ; Fer muriate, Hauy ; Axotomous pearl mica, Molis. Hexagonal ; P 115 37' ; crystals chiefly ooP. OP, prismatic or tabular, but sometimes with faces of P or other pyramids. Also massive and granular. Cleavage, basal perfect ; prismatic along ooP imperfect. Brittle : H. = 4 4-5 ; G. = 3'0 3'2. Trans- lucent to opaque. Lustre resinous, metallic pearly on OP. Liver- brown to olive-green. In the closed tube yields water and then yel- low drops of chloride of iron. B.B. fuses to a black magnetic globule. With borax and salt of phosphorus, shows reaction for iron, and man- ganese ; with salt of phosphorus and copper-oxide for chlorine. Wholly soluble in concentrated nitric acid. Chem. com., according to L. Gmelin, lop'e si + ISidn si + 34 H + Fe 2 Cl 3 = 38'5 silica, 22 iron protoxide, 22 manganese protoxide, 13 iron peroxide, 3'4 hydrochloric acid, and 1-1 water. Analyses. Silica. Iron perox Man- gan. Alu- mina. Lime Hydr. acid. Watr. Total. 1 35-40 32-60 23-10 0-60 6-50 ... 98-20 Hisinger. 2 35-85 35-48 23-44 1-21 29-15 jundt. 98-8!; Do. 3 35-85 21-81 2M4a ... 1-21 14-0961 5-90c 100- No. 2 by Rammelsberg. (a) Protoxide; (6) chloride of iron; (c) water and loss. No. 3 is Rammelsberg's interpretation of analysis No. 2 on the supposition that the chlorine forms a basal salt with iron. It occurs with calc-spar and hornblende in magnetic iron-ore in the Bjelkey- grube, near Nordmark (Nos. 1, 2), and at Nya Kopparberg, in Swe- den. 89. CRONSTEDTITE, Steinmann ; Chloromelan, Naumann ; Rhom- bohedric Melan-mica, Mohs. Rhombohedric, perhaps hemimorphic, chiefly in radiated, columnar groups, sometimes ending in hexagonal prisms. Cleavage, basal perfect ; cleavage planes slightly convex ; thin lamina; elastic. H. = 2-5 ; G. = 3-3 3-5. Opaque or translucent. Highly vitreous. Raven-black ; streak dark-green. B.B. intumesces, and melts on the edges slowly to a black glass Cto a steel-grey globule, v. Kobell). With borax forms a glass coloured by iron. Gelatinizes with hydro- 194 STILPNOMELAN BRUCITE. [Mica chloric or sulphuric acid. Chem. com. p^ 2 si + 2re 2 si + 5 H, but part of the iron protoxide often replaced by magnesia. Analyses. Silica. Iron perox. Iron protox. Mang. perox. Magnesia. Water. Total. 1 22-45 58-85 2-89 5-08 10-70 99-97 Steinmann, Przibram. s 3 22-45 16-3 35-35 27-11 75-5 a 2-89 5-08 4-16 10-70 7-3 103-58 103-2 Do. cor. by v. Kobell. Wernekink. (a) Protoperoxide ; (6) alumina. The cronstedtite occurs with iron pyrites, calc-spar, and iron ores, in the silver mines of Przibram in Bohemia ; also at Wheal Maud- lin, Cornwall. The Sideroschisolite of Wernekink (No. 3), found with iron ores at Conghonas do Campo in Brazil, agrees in external aspect, and is perhaps identical. B.B. very easily fusible (Wernekink) ; infusible (Berzelius). The analysis was performed with only three grains of the mineral, which may account for the difference. 90. STILPNOMELAN, Glocker. Crystallization unknown ; massive and disseminated, with a gra- nular or radiating-foliated texture. Cleavage in one direction very perfect. Bather brittle. H. = 3 4 ; G. = 3 3'4 (2-76 Brei- thaupt.) Opaque ; lustre vitreous, inclining to pearly on the cleavage planes. Colour greenish-black to blackish-green ; streak olive-green to greenish-grey. In closed tube yields water. B.B. fuses with diffi- culty to a black shining globule, and with fluxes shows reaction for iron and silica. Imperfectly decomposed by acids. Chem. com. 6 Fe si + Al si 3 + 66 = 46-5 silica, 36 iron protoxide, 8-5 alumina, and 9 water. Analyses. Silica. Iron Alu- Lime. Mag- Water. Potash. Total. protox. mina. 1 i 43 19 46-50 37-05 33-89 8-16 7-10 1-19 0-20 3-34 1-89 5-95 7-90 98-88 97-48 Rammelsberg. Do. 3 45-43 35-38 5-88 0-18 168 9-28 97-83 Do. 4 46-17 35-82 5-88 ... 2-67 8-72 075 100 Do. Occurs with calc-spar, quartz, and iron pyrites, in clayslate at Obergrund in Austrian Silesia. R. thinks the specimen analysed mixed perhaps with chlorite. 91. BRUCITE, Beudant; Native Magnesia, Bruce, Jameson; Hy- drate of Magnesia, Brewster, Phillips; Magnesie hydrate"e, Hauy ; Talk hydrat, v. Leonhard; Rhoinbohedral Kuphon- mica, Mohs. Hexagonal ; OP . ooP, also massive, foliated, or columnar. Cleav- Family, ,] II YDROM AGNE SITE . 195 age, basal very perfect. Sectile, in fine laminae flexible ; H. = 2 ; G. = 2 -a 2-4. Semitransparent or translucent ; lustre pearly ; colourless, or greyish and greenish-white. By friction becomes posi- tively electric (Hauy). In the closed tube yields water. B.B. in- fusible alone, with cobalt solution becomes pale-red. Easily soluble in acids. Chem. com. Mg H with 69 magnesia, and 31 water. Analyses. Mag- nesia. Water. Mang. perox. Iron protox. Lime. Total. 1 2 3 4 5 6 6975 67-98 6667 68-34 70 64-0 30-25 30-96 30-39 30 '90 30 29-0 r^ 1- 1-57 0-64 V 57 1-18 0-12 2'5 o'-19 2 : (ta 100-0 10051 100 100 100 97-5 Fyfe, Unst. Thomson, do. Stromeyer, do. Do. Hoboken. Bruce, do. Vauquelin, do. (a) Silica. G. Rose finds that perfectly pure transparent fragments effervesce in hydrochloric acid, and infers that this mineral contains carbonic acid. At all events it gradually acquires this on exposure, becoming dull and pulverulent. It is found in veins in serpentine, at Swinaness in Unst, Zetland, at Hoboken in New Jersey, and at Pyschminsk, near Beresowsk in Siberia. 92. HYDROMAGNESITE, v. Kobdl. Cryptocrystalline or amorphous. Occurs in roundish masses, with an earthy or imperfect conchoidal fracture ; H. = 1 5 2 ; G. un- known. Lustre dull, colour white. Feels greasy, and leaves a mark on paper. B.B. is infusible. In closed tube gives out water and acts like pure magnesia. Soluble with effervescence in acids. Chem. com. Mg 4 c 3 + 4 H with 36*2 carbonic acid, 44*0 magnesia, and 19'8 water. Analyses. Carbo- nic acid. Mag- nesia. Watr. Silica. Iron perox. Vein- stone. Total. 1 2 36-82 36-00 33-10 42-41 4396 24-28 18-53 19-68 17-40 0-57 0-36 0-27 2522a 1-39 99-99 100 100 Trolle-Wachtmeister, Hoboken. v. Kobell, Kumi. Do. Vesuvius. (a) Lime. This mineral is thus identical with the magnesia alba of chemists, t is found in serpentine at Hoboken in New Jersey, with brucite, pro- bably as a produce of its decomposition, and at Kumi on Negroponte in Greece. Also it is said in the East Indies. No. 3 is the Hydro- magnocalcite of Rammelsberg, a kind of sinter found in yellowish- 196 NEMALITE SEYBERTITE. [Mica white spherical masses on Vesuvius, and which may be regarded as hydromagnesite with the magnesia partly replaced by lime. 93. NEMALITE, Nuttal. Occurs in fine elastic asbestiform fibres ; H. = 2 ; G. = 2*4. Lustre silky ; colour white, greyish, or yellowish. B.B. acts like brucite ; slowly decomposed by acids slightly effervescing. Chem. com. by Council's analysis 5 Mg H + (Mg c + H ) = 61 '36 mag- nesia, 11*19 carbonic acid, and 27'45 water. Analyses. 1 2 Mag- nesia. Silica. Iron perox. Iron protox. Water. Carbo- nic acid. Total. 5172 57-86 12-57 080 5-87 2 : 84 29-67 27-96 i6"oo 99-83 99-46 Thomson, Hoboken. Connell, Do. Forms veins in serpentine at Hoboken in New Jersey, and in green- stone at Piermont, New York, and Bergen Hill, New Jersey. The mineral analysed by Thomson seems a distinct species, with chem. COm. 4 MgH 2 + Mg 2 Si. 94. SEYBERTITE, Clemson; Holmesite, Thomson; Clintonite, Dana; Xanthophyllite, G. Rose; Chrysophane, Breitkaupt; Rhornbo- hedric pearl-mica, Mohs. Crystalline, probably hexagonal. Sometimes in hexagonal tables ; usually massive and coarsely foliated. Cleavage very perfect in one direction ; traces in another ; H. = 4-5 6 ; G. =3. 3 '16. Trans- lucent or transparent in thin foliar ; pearly on the cleavage planes ; wax -yellow, yellowish, or reddish -brown. Soluble in concentrated acids, but the xanthophyllite with difficulty in warm hydrochloric acid. B. B. infusible alone, but some become white and colour the flame yellow. Chem. com. uncertain. Analyses. 1 2 3 4 5 Silica. Alu. mina. Mag- nesia. Lime. Iron perox. Soda. Watr. Total. 17-0 19-35 21-4 16-30 20-00 37-6 44-75 467 43-95 43-22 24-3 9-05 9-8 19-31 25-01 10-7 11-45 12-5 13-26 4-00 5-Oa 4-80 4-3 2-53a 3-60 '".b : 61 0-57 3.6 4.55 3.5 4.33 3.60 98-2 98-25 98-2 100 '29 100 Clemson. Richardson. Plattner. Meitzendorf. y. Kobell. (a) Protoxide ; (b) + 1-35 manganese protoxide, 2-05 zirconia, and 0'90 fluoric acid. The Seybertite (Nos. 1, 2, 3) occurs in granular limestone near serpentine at Amity, New York. The Xanthophyllite (No. 4, mean of four), along with magnetic iron ore in talc state, near Slatoust in the Ural. The Disterrite of Breithaupt (No. 5), from Monzoni in the Fassathal, Family.'] M ARGARITE P YROPH YLLITE . 197 Tyrol, occurs in hexagonal tables with basal cleavage perfect, but difficult to obtain. H. = 5 on basis, 6 6'5 on the prism ; G. = 3'04 3*05. Translucent ; lustre pearly ; colour when fresh blackish- green, but reddish -brown after exposure. B.B. infusible, but becomes greyish-white. Dissolves slowly in borax or salt of phosphorus. Not soluble in hydrochloric acid, but after long boiling in concen- trated sulphuric acid. The above minerals, if distinct, are closely allied species (connecting the silicates and aluminates, v. Kobell). 95. MARGARITE, Fuchs ; Pearl-mica, Jameson ; Hemiprismatic Pearl-mica, Mohs. Monoclinohedric of unknown dimensions. Rarely crystallized in six-sided tables, formed of OP . cP . ( ooPoo ). Generally granular foliated. Cleavage, basal very perfect. Thin plates slightly elastic. H =3-5 4-5 ; G. = 3'032. Translucent ; lustre vitreous, or pearly on cleavage planes ; snow-white, reddish-white, or pearl-grey. B.B. intumesces and difficultly fusible. Soluble in acids. Chem. com. un- certain. Analyses. Silica. Alu- mina. Iron perox. Mangan protox. Lime. Mag- ncsia. Soda. Watr. Total. 1 37-00 2 33-50 4M-50 5800 4-50 0'42a o'-03 8-96 7-50 : 05 1-24 1-00 93-20 99-50 Dumenil. Gottingen laboratory. (a) Protoxide. Occurs at Sterzing in Tyrol with chlorite. Dumenil's analysis is very imperfect. No. 2 is given by Hausmann. 96. PYROPHYLLITE, Hermann. Probably rhombic, but crystals very indistinct. Massive and ra- diated columnar or foliated. Cleavage very perfect parallel to the columnar structure. Flexible in thin plates. Sectile, H. = 1 ; G. = 2-7 2*8. Translucent ; pearly ; colour, light verdigris-green to greenish or yellowish-white. In closed tube yields water, and be- comes silvery. B.B. in the forceps exfoliates and swells up with many twistings to a snow-white infusible mass. With cobalt solution becomes blue. Partially soluble in sulphuric acid. Chem. com. un- certain. Analyses. 1 2 3 Silica. Alu- mina. Mag- \ Iron nesia. perox. Water. Silver. Total. 59-79 66-14 49-08 29-46 25-87 278 4-00 1-49 16-96 1-80 16-12 o 5-62 5-59 10-28 trace. 0-396 100-67 99-48 9972 Hermann, Ural. Rammelsberg, Spaa. Thomson, Vermont. (a) Protoxide; (b) lime. 198 ANAUXITE PHOLERITE ROSELLAN. [MlCd The pyrophyllite (Nos. 1, 2), formerly considered talc, occurs in quartz veins in the beresite or granite, between Beresowsk and Pyschminsk, in the Ural, and also near Spaa. No. 3 is the Vermi- culite of Thomson, which resembles a fine scaly talc, and B.B. acts like pyrophyllite. It is found at Millbury, Mass., and in Vermont, North America. These substances are probably mere products of the decomposition of other minerals ; and the vermiculite is said by Dana to be a mechanical mixture. 97. ANAUXITE, Breithaupt. Massive and granular, with a very perfect cleavage in one direc- tion. H. = 2 3 ; G. = 2-26. Translucent on the edges ; lustre pearly, colour greenish-white. In the closed tube gives water, and blackens. B.B. becomes white, and fuses on thin edges. With co- balt solution blue. Chem. com. by an imperfect analysis of Plattner, 55-7 per cent, silica, much alumina, a little magnesia, iron protoxide, and 11-5 per cent, water. Occurs at Bilin, Bohemia. 98. PHOLERITE, Guillemin; Nacrite, Vauquelin? Cryptocrystalline, massive, and fine scaly. H. = 0-5 1 ; G. = 2*35 2-57. Lustre glimmering or pearly. Colour snow-white or yellowish -white. In closed tube gives water. B.B. infusible; be- comes blue with cobalt solution. Chem. com. ^i 2 si 3 + 4 A. Mean of three analyses by Guillemin, from Fins in the Allier dept., 41-78 silica, 43-10 alumina, and 15'12 water. The nacrite of Vauquelin was probably mica ; that analysed by Thomson a variety of talc. 99. ROSELLAN, Svariberg ; Rosite, Hausmann. Occurs in small grains imbedded in limestone. Cleavage in one direction perfect. H. = 2-5 ; G. = 2-72. Translucent ; lustre splendent on cleavage planes. Colour fine rose red ; streak white. In closed tube gives out water and loses its colour. B,B. fuses with di- fficulty to a white slag ; with soda fuses readily. Chem. com. ji 2 si 3 + R si + 2 H. Svanberg found 44-90 silica, 34-51 alumina, O69 iron peroxide, 0*19 manganese peroxide, 3-59 lime, 2-45 magnesia, 6-63 potash, and 6'53 water (= 99-48). Occurs at Aker and Baldurstad in Sodermanland, Sweden. Family.'] HORNBLENDE. 199 VIIL FAMILY. HORNBLENDE. 100. HORNBLENDE, Werner, Phillips, -c.; Amphibole, Hauy, r. ; Hemiprismatic Augite-spar, Mohs. Monoclinohedric ; C = 75, ooP 124 30', P 148 30'. The crys- tals are partly short and thick, partly long and thin prismatic, formed especially by ooP (M) and (ooPoo) (ar), and bounded on the ends chiefly by OP and P (r), or also by (Poo ) 148 16'. Fig. 129 is a very Fig. 129. characteristic form. The crystals are imbedded, or attached, and in druses. Macles are common, united by a face of the orthopinakoid, and the chief axis the twin axis. Very often massive, in radiated, parallel, or confused fibrous or columnar aggregates, or in coarse or fine granular masses. Cleavage, prismatic along ooP very perfect, orthodiagonal and clinodiagonal very imperfect. H. = 5 6 ; G. = 2-9 3'4. Pellucid in all degrees. Lustre vitreous, but sometimes pearly or silky. Co- lourless ; often white, but usually some shade of grey, yellow, green, brown, or black. B.B. fuses, generally intumescing and boiling, to a grey, green, or black glass. Those containing most iron are most fusible, and are also partially soluble in hydrochloric acid, which scarcely affects the others. Cheni. com. very variable, and hardly reducible to any general formula. L. Gmelin gives R 5 si 8 , or 3 R & + R 2 si 3 , as the basis of all hornblendes ; R being essentially mag- nesia and lime in variable proportions, and occasionally replaced by protoxide of iron. Some contain fluoride of calcium ; very many, especially the green and black varieties, a considerable amount of alumina. Analyses, next page. These analyses, and many others might be added, show the va- riations in composition to which this mineral is liable. The most important is in alumina, which may either form an aluminate mixed in indefinite proportion with the silicates, or perhaps replaces a por- tion of the silica. Rammelsberg has found that the oxygen of the bases in Nos. 5, 17, 20, 21, 22, 23, 24, is to that of the silica and alumina combined as 4 : 9 nearly, which he regards as the atomic pro- portion of the pure silica hornblendes, and it is still nearer 5 : 12, the proportion assumed above from L. Gmelin. Hence the latter view seems the more probable. In external aspect the mineral also shows much diversity, giving rise to varieties often considered species, and described as such. The following are the more remarkable : 1. Tremolite, Grammatite or Calamite, white, grey, green, rarely 200 HORNBLENDE. [Hornblende Silica. Mag- nesia. Lime. Iron prot. Mang. prot. Alu- mina. Fluor, acid. Watr. Total. 1 60-10 24-31 12-73 1-00 0-47 0-42 0-83 0-15 100-01 Bonsdorff, Fahlun. 2 59-75 25-00 14-11 0-50 trace. 0-94 0-10 100-40 Do. Gulsjo. 359-5 26-8 12-3 trace 1-4 ... 100-00 Beudant, Cziklowa. 4 58-07 24-46 12-99 1-82' 97-34 Damour, St Gotthardt. 5 47-21 21-86 12-73 2-28 o : 57 13-94 0-90 0-44 99-93 Bonsdorff, Aker. 65975 21-10 14-25 3-95 0-31 0-76 100-12 Do. Taberg. 759-50 19-30 12-65 8-60 "** 100-05 Murray, Do. 858-20 22-10 15-55 3-08 : 21 0-14 : 66 0-14 100-08 Bonsdorff, Tarantaise. 958-19 30-79 7-93 0-18 1-866 98-95 Heintze, Ural. /-* 1058-48 31-38 0-04 9-22 0-88 100 Lappe, Koruk> Greenland. 11 57-98 1256 22-38 23 12-95 2 632 1 3 4'" 0-58 3 :::. 100-21 101 Rammelsberg, Kuhnsdorff L.Gmelin, Kongsberg. 13 56-74 24-35 13-94 2-38 1-67 99-08 Vopelius, Do. 14 40-27 13-38 13-80 1534a ... 16 : 36 0-46 99-61 Goschen, Cernosin. 15 44-03 2-33 10-08 25-55a 14-31 3-44 99-74 Madrell, Do. 16 47-62 14-81 12-69 15-78 0*32 7-38 ... 98-60 Hisinger, Fahlun. 17 45-06 16-74 13-36 7-92 1-67 13-51 0-22 98-46 Do. Lindbo (m. of 2). 1853-50 4-65 11-35 2225 0-35 4-40 ... 0-60 97-10 Do. Garpenberg. 1941-50 19-40 14-09 7-75 0-25 13-75 50 97-24 Do. Pargas. 20 45-69 18-79 13-83 7-32 0-22 12-18 1-50 99-53 Bonsdorff, Do. 21 48-83 13-61 10-16 1875 1-15 7'48 0-41 0-50 100-89 Do. Nordmark. 22 49-07 20-29 10-33 9-77 9-24 98-70 Kudernatsch, Kongsberg. 23 45-31 14.28^ 10-49 15-93 11-88 o'-66e 98-55 Do. Veltlin. 24 42-24 13-74 12-24 14-59 0-33 13-92 97-06 Bonsdorff, Wetterau. 25 40-08 13-50 11-01 13'69a 17-59 1*10 oTs/ 100 Struve, Bilin. 26 46-03 18-48 10-23 17-44 8-37 100-55 Clausbruch. 27 49-27 0-42 1-50 36-12 0~62a 200 ... g 9817 v. Kobell, Greenland. 28 50-51 ... 1-56 31-55 8-92a 2-49 0-96 95-97 Thomson, Faroe. 29 46-57 5-88 5-91 24-38 2-07 3-41 '.'.'. h 100 99 Plantamour, Brevig. (a) Peroxide; (b) loss by heat ; (c) protoperoxide; (d) with manganese; (e) titanic acid and silica ; (/) + 1-89 potash, andjO'96 soda ; (g) + 8-00 soda with traces of potash, and 0'24 chlorine ; (h) + 7-79 soda, 2 96 potash/2-02 titanic acid, and fluorine not determined. yellowish or blue; in long prismatic crystals of ooP. coPco, or in columnar aggregates. The crystals often bent and striated longitu- dinally. Lustre pearly or silky; semitransparent or translucent; B.B. fuse readily to a white or nearly colourless glass ; analyses, No. 1 5 above. Chem. com. of No. 1 and 2 nearly 3 Mg 5 s'i 6 + ca 5 si 6 + Ca F. Occurs chiefly disseminated in dolomite, granular limestone, or other subordinate beds in the crystalline rocks ; rarely in veins. With magnetic iron in Lapland, at Philipstad in Sweden, Arendal, &c. Very fine varieties at Campo longo, St Gotthardt, and in other parts of the Alps ; in the Pyrenees, Silesia, Siberia, North America, and in many parts of Scotland, as in the limestone of Glen Tilt. 2. Actinolite, Actinote or Strohlstein ; colour green, inclining either to black, or to grey, yellow, or brown. Translucent, or only on the edges. In imbedded long prismatic crystals ooP. ( coPoo ), or radi- ated columnar masses. B.B. melts to a greenish or blackish enamel. Analyses 6, 7 above. Occurs in talc, chlorite, and mica slates, also in gneiss, euphotide, and serpentine ; and alone or with other sili- cates often forms subordinate beds in the crystalline rocks ; but is Family.'] HORNBLENDE. rather rare in veins. Fine varieties are found in Sweden and the Tyrol ; also in Siberia, Finnland, Greenland, and North America. G. Rose found that actinolite from the Zillerthal when melted, as- sumed on cooling, the form of augite ; and Mitscherlich observed this also of tremolite. It has hence been asserted that hornblende and augite differ only in the mode of cooling ; but it should first be shown that no chemical change or decomposition occurred, and that the whole hornblende substance reappeared in the form of augite. 3. Asbestus, Amianthus, and Byssolite ; fine fibrous varieties chiefly of tremolite and actinolite, of white, grey, or green colours. The fibres, often easily separable, elastic, and flexible, have been con- verted into incombustible cloth ; and in 1727, some copies of a dissertation on this mineral by Bruckmann were printed at Bruns- wick on paper prepared from it. In rock-cork, the fibres are inter- woven into a loose felt-like texture, so light as to swim on water, and sectile like common cork ; in mountain leather they form flat, flexible pieces ; and in rock-wood they occur in long parallel curved masses, with a closer texture. Asbestus is common in Savoy, the Tyrol, and in Corsica, in such profusion, that Dolemieu used it for packing his other specimens. Rock-cork is met with in Saxony and Sweden ; at Portsoy and Leadhills in Scotland ; and in a recent marl formation with meerschaum at Vallecas, near Madrid ; rock-leather chiefly at Leadhills and Strontian ; and rock-wood near Sterzing in the Tyrol, with galena and zinc. Asbestus, however, is rather the name of a particular condition of several minerals, as augite, than a mere variety of hornblende ; and chemical analysis can often alone de- cide to what species it belongs. Nos. 8, 9, 10, 11 are this variety, the latter named Kymatine by Breithaupt. Below are analyses of rock- wood (No. 1), mountain-leather (No. 2), mountain-cork (No. 3), mountain-wood (No. 4), of a peculiar character, and the xylite of Hermann (No. 5), of which only one specimen, supposed from the Ural, is known. Silica. Mag- nesia. Lime. m a . Iron protox. Mang. prot. Watr. Total. 1 54-92 2 57*65 3 5775 4 55-55 5 44-97 26-08 2-06 10-85 14-96 5-53 10-00 14-05 0-11 6-71 1-64 9-50 1-95 0-04 12-60 5-80 18-90 19-50a 38-61a 1*85 5-28 21-70 10-31 4-18 100-52 106-71 10535 99-97 100-10 Thomson, Tyrol. Do. Strontian. Do. Piedmont. Thaulow, Sterzing, (m. of 2.) Hetman, Ural ? (a) Peroxide. 4. Anthophyllite ; clove-brown, translucent, in radiating coarse columnar aggregates. B.B. very difficultly fusible. In it the lime is 202 HORNBLENDE. \_Homblende chiefly replaced by protoxide of iron. First found in a bed with common hornblende, tremolite, and mica, in mica slate at Kongsberg, Norway, since at Brakka near Brevig in gneiss, and in the United States. Nos. 12 and 13 are analyses of this variety ; Nos. 9, 10 of asbestus similar in composition. 5. Hornblende, of green or black, seldomer brown or grey colours ; G. = 3-3 4. B.B. fuses rather easily to a yellow, greenish, or black enamel or glass. Three varieties are distinguished. () The noble or Pargasite, of a pale celadine or olive-green colour, and with a strong pearly or vitreous lustre. (&) Common hornblende, dark- leek or blackish-green, opaque, crystallised in druses, massive, or disseminated as a constituent of many rocks. Streak greenish-grey. Analyses Nos. 16-23. (c) Basaltic, velvet-black, foliated, opaque, streak grey or brown. Analyses Nos. 14, 15, 24, and 25. Hornblende is very liable to decomposition. The mineral is first covered with a rusty crust, and finally falls down into a brown feru- ginous earth. In this process the protoxide of iron is changed into the hydrated peroxide, and the magnesia and lime are partially removed. (Compare anal. No. 14 of the fresh with No. 15 of the decomposed mineral.) This tendency to decomposition confers great fertility on the soils resting on rocks containing this mineral. Hornblende is sometimes converted into a kind of steatite, the change in a specimen of pargasite mentioned by Blum having begun at the centre. In the Wolfsberg near Cernosin, Bohemia, it seems changed into a red jasper. The Uralit in which common hornblende assumes the form of augite will be noticed below. This mineral is an important constituent of many rocks ; the com- mon variety forming almost the entire mass of the granular horn- blende rock and hornblende slate. With common felspar it composes syenite, and with albite the diorite or greenstone. It occurs more incidentally in granite, gneiss, mica slate, chlorite slate, euphotide, and hypersthene rock. It is also common in granular limestone, and in beds with magnetic iron, with copper, iron, and cobalt pyrites, and with other ores. Noble hornblende is rare, and chiefly met with in crystalline limestone. Basaltic hornblende again chiefly in vol- canic rocks, as basalt, leucite-porphyry, and trachyte. Distinct crys- tals of this mineral are rather rare, but occur in the Ural, at Arendal, and several places in Bohemia. Norway exhibits large masses of hornblende rock ; hornblende slate forms many portions of the Alps ; and both are common in the Scottish Highlands, where, however, horn- blende has not always been distinguished from augite. It is regarded as a useful addition to the magnetic iron ores in smelting, unless united with the sulphuret of iron, when it renders the metal brittle. Family.'] HORNBLENDE. 203 Arfvedsomte of Brooke is also probably a variety of hornblende. Colour pure black ; opaque ; streak greyish-green. Cleavage very perfect along the faces of a prism of 123 55'. G. = 3-44 ; H. = 6. Fusible in fine splinters in the flame of a candle. B.B. intumesces much, and melts to a black magnetic globule. Not soluble in acids. Chem. com. similar to hornblende, but specially 3 Fe 5 si 6 + Na 5 si 6 , part of the soda being replaced by lime, part of the silica by alumina. Analyses Nos. 27, 28. It occurs in crystalline schists at Kangerdlu- orsuk, Greenland ; also in the zircon syenite of southern Norway, and with magnetic iron at Arendal. The .ZEgirin from Brevig, Nor- way (No. 29), seems to be this variety. The Raphelite of Thomson, from Perth, in Upper Canada, occur- ring in groups of delicate acicular crystals, translucent, vitreous, or resinous, and of a white or bluish-green colour, is, according to Dana, allied to arfvedsonite or an impure variety mixed with felspar. H. = 3*5 ; G. = 2'85. B.B. becomes white, opaque, and fuses on the edges. Breislackite of Brocchi, fine capillary woolly crystals of a yellowish, reddish, or chestnut- brown colour, found in the lava of Capo di Bove near Rome and Vesuvius, is also a variety of hornblende. Its composition is not well known, but it is said to contain copper, yield- ing with salt of phosphorus a green globule, which becomes red in the reducing flame. The Uralite of G. Rose is a dark-green or greenish-black mineral, with the outward form of augite, the internal structure and composi- tion of hornblende. It was first observed in the augite porphyry of the Ural, but since in the augite rocks of the Veltlin, of the East and West Indies, of America, and in great variety at Arendal. In some specimens, the whole mass is Uralite, in others a small kernel of light-green vitreous augite remains ; in a third there is a mere coating of the hornblende substance. Sometimes the two are irregularly combined, at other times regularly with their cleavage planes in one zone. Those of the uralite appear fibrous or striated parallel to their edges. G. Rose thinks this mineral a pseudomorph of hornblende after augite ; others rather incline to regard it as an intimate inter- mixture of the two minerals in indefinite proportions, and so that where the hornblende predominates it gives the character to the cleavage, the augite being only seen in the fibrous aspect of the planes. A variety from Lake Baltym contained 53'05 silica, 12*90 magnesia, 12-47 lime, 16'37 iron protoxide, 4'56 alumina, (= 99*35) (Kudematsch), which is not unlike the hornblende from Nordmark, No. 21 above. 204 AUGITE. [Hornblende 101. AUGITE, Werner, Phillips ; Pyroxene, Hauy ; Paratomous Augite-spar, Mohs. Monoclinohedric ; C. = 74, ooP 87 6', P 120 39', P 131 29', 2P 96 36' ; some of the more common combinations are ooP (m) . ooPoo (r) . ( ooPoo ) (0 . P 0) . (fig. 130) ooP. 2P. OP3P. . ooPoo , and Fig. 130. Fig. 131. II ooPoo . ( ooPoo ) . PGO . GoP. The crystals are almost always prisma- tic, imbedded, or attached, and then generally united in druses. Common also in granular, columnar, and scaly aggregates. Macles (fig. 131) are common, formed according to various laws, but most frequently united by a face of the orthopinakoid, and with the chief axis the twin-axis. Cleavage, prismatic along ooP generally rather imperfect, sometimes- perfect ; macrodiagonal and brachydiagonal im- perfect. H. = 5 6 ; G. = 3-2 3'5. Pellucid in all degrees. Lustre vitreous, in some varieties pearly on GcP . Colourless, and occasionally white, but usually coloured, grey, green, or black. B.B. generally fusible ; imperfectly soluble in acids. Chem. com. general- ly casi + R si, where R is essentially magnesia and protoxide of iron. Many may be represented by the formula 3c a si + 2n g si + Fe si ; and the augites without alumina form three divisions, according to the relative prevalence of the latter two bases. Their ideal composition would be as follows : Silica. a. Magnesia-augite, ...... 56'36 b. Magnesia- iron-augite, 52'72 c. Iron-augite, ............ 49'52 Lime. Magnesia. Iron. 25'46 18'18 23*81 8'50 14-97 22-37 ... 28-11 The very dark-green and black augites also contain about 7 per cent. r alumina, which, as in hornblende, may either replace a portion of the silica, or form a peculiar compound mixed with the preponde- rating silicates. Analyses, next page. Family. ,] AUGITE 205 Silica. Lime. Mag- nesia. Iron prot. Mang. prot. Alu- mina. Total. 1 54-15 24-74 18-22 2-51 0-18 0-20 1(10-00 Wackenroder, Fassathal. 2 54-83 24-76 18-55 0-99 0-32 0-28 99-73 Bonsdorff, Tammare Finnland. 3 54-64 4 57-40 5 53-97 24-94 23 10 25-60 18-00 1674 17-86 1-08 0-20 2-00 2-OOa : 57 0-43 100-66 97-87 100 H. Rose, Orrijerfvi Finnland. Trolle-Wachtmeister, Tjotten Norway. Hermann, Achmatowsk. 6 57-26 23-66 13-23 1-66 1-73 2 : 33e 99-85 v. Kobell, Jenbach Tyrol. 7 54-86 23-57 16-49 4.44 0-42a 0-21 9999 H. Rose, Sala Sweden. 8 54-08 23-47 11-49 10-02 0-61a 99-67 Do. Dalecarlia. 9 54-55 20-21 15-25 8-14 073a : 14 99-02 Do. Do. 10 50-38 19-33 683 2040 tracea 1-83 98-77 Seybert, Lake Champlain, N. A. 11 50-00 20-00 4-50 18-85 3-00 ...6 97-25 Berzelius, Degeroe Finnland. 12 53-56 23-86 16-27 4-48 1-87 0-25 100-29 Reuterskold, Lanbanshytta. 13 52-18 22-00 7-06 16-13 1-61 1-42 99-40 G. Funk, Nordmark. 14 51-80 19-07 12-01 6-92 6'56c 97-38 Nordenskiold, Pargas. 15 50-42 18-78 16-32 7-40 658 99-50 Kudernatsch, Rhon (m. of 2). 16 4979 22-54 12-12 8-02 ... 6-67 99-14 Do. Gillenfelder Maar Eifel. 17 47-05 23-77 15-35 7-57 ... 5-16 98-90 Do. Do. Do. 18 50-12 20-05 1370 11-60 ... 4-21 99-68 Do. Zigolonberg Fassathal (m. of 2). 19 50-55 22-29 13-01 7-96 4-85 98-66 Do. Aetna. 20 50-90 22-96 14-43 6-25 5-37 99-91 Do. Vesuvius. 21 47-78 22-95 ... 27-01 ... 97-74 Wolff, Arendal. 22 49-01 20-87 2-98d 26-08 ... 98-04 H. Rose, Tunaberg Sweden. 23 56-0 151 8-9 13-5 2-<)/ 97-5 Keating, New Jersey. 24 44-50 22-15 4"oO 12-30 14-550 99-35 Thomson, Do. 25 55-87 1776 20-33 4-31 l'-12 9939 Meitzendorf, Schwarzenstein Tyrol. (a) Peroxide; (6) + 0'90 loss by heat ; (c) + 1-02 water; (d) with manganese ; (e) + trace of potash ; (/) + I'O oxide of zinc, and 1-0 loss by heat; (g) + T85 moisture. Several varieties or sub-species of augite are distinguished by mi- neralogists, the more important being : 1. Diopside, greyish or greenish-white, to pearl-grey or leek-green ; streak white. Crystallized or in broad-columnar, or concentric lamel- lar aggregates. Transparent to translucent on the edges. Not affected by acids ; B.B. fuses to a whitish semitransparent glass. Analyses Nos. 1-5. Occurs in beautiful crystals in the Mussa Alpe in Piedmont, and at Swartzenstein in the Tyrol with garnets and chlorite. It is abundant in the Alps, in Scandinavia, Finnland, the Ural with garnet in chlorite slate, at Bolton in Massachusetts in granular limestone, and in other parts of North America. G. Rose found that diopside fused in a porcelain crucible resumed its peculiar structure on cooling. Berthier and Mitscherlich have also produced a similarly crystallized body by fusing silica, lime, and magnesia in due proportion. Ana- tysis No. 6 is a furnace-slag of similar composition, occurring in thin tabular crystals of a greenish colour, with distinct cleavage. 2. Sahlite, Malacolite, colour various shades of green, rarely yellow, brown, or red. Streak white ; translucent, or only on the edges. Vitreous, inclining to pearly. Seldom crystallized (Baikalite), mostly columnar or lamellar. B.B. melts to a dark-coloured glass. Analy- ses Nos. 7-13. Fine sharp crystals of high lustre and dark or pis- taccio-green colour occur in the Fassathal (Fassaite), the Brosso valley in Piemont, near Arendal, at Philipstadt in Sweden, in the 206 AUGITE. [Hornblende vicinity of Lake Baikal (Baikalite), and at Monroe in New York. Sahlite is found more often in beds than in veins, as of copper or iron pyrites, magnetic and other iron ores in many parts of Sweden ; and with galena at Sahla. Also in granular limestone in Sweden, Scot- land, Tyrol, and North America. It is thought useful as a flux in reducing ores, especially of iron. The coccolite is merely a distinct granular sahlite or augite. 3. Augite is leek-green or blackish-green, greenish -black, pitch or velvet-black ; rarely brown. Streak greenish -grey. Lustre vitreous to resinous. Translucent or opaque. The crystals are usually im- bedded, but sometimes found loose in volcanic ashes or sand, and then often appear as if semi-fused. Only slightly affected by acids. B.B. fuses to a black, often magnetic glass. This is the most common form of this mineral. It is an essential component of many wide-spread rocks, as of basalt, dolerite, clink- stone, and augite porphyry. Sometimes it appears in single distinct, imbedded crystals, as at Boreslan in the Mittelgebirge, the Wolfsberg near Cernosin, in the Rhon and Vogelsgebirge, the Kaiserstuhl, in Auvergne, on Vesuvius, and in many parts of Scotland. In rocks it is associated chiefly with labradorite, and also with olivine, leucite, or nepheline, whilst quartz rarely, if ever, forms a constituent of the mass. It occurs in a similar manner in blocks ejected from volcanoes, and in some meteoric stones. In primary formations it is most com- mon in granular limestone, either in crystals or grains, often appa- rently fused. It occurs thus in great beauty at Pargas in Finnland, and in many localities in North America. It is also found in beds of magnetic iron, as at Arendal, either mixed with the ore, or massive and united with calc spar in distinct veins. In such cases it acts be- neficially on the production of the metal. Augite, or a substance similar in composition and form, has been found in the slag of fur- naces ; and Berthier, by fusing silica, lime, and magnesia in the pro- per proportions, and allowing them to cool very slowly, obtained a similar crystallized mass. 4. Hedenbergite, black or blackish-green, opaque or translucent on the edges. B.B. melts to a black magnetic glass. Seems to be a lime- iron augite, but its composition still rather uncertain. (Nos. 21, 22 anal.) Occurs with calc-spar in the mines of Tunaberg. The Jeffer- sonite, from Sparta, New Jersey, seems related, but neither its form nor composition (comp. anal. 23, 24) well ascertained. It is dark olive to black or brown, with resinous or imperfect metallic lustre. 5. Amianthus, some asbestiform minerals are probably augite (No. 25), but, as stated above, the greater number are rather horn- blende. Family] AUGITE. 207 Augite seems liable to various processes of decomposition, neither the causes nor mode of which are well understood. A common change is decomposition through the action of air and water, the augite and the rocks of which it forms the chief part, gradually ac- quiring a rusty colour, from the formation of a hydrous peroxide of iron, and at length falling down into earth or clay. In other cases it is changed into green earth, various stages in the process being often visible, as in an augite porphyry in the Pozza mountains in Tyrol, whilst the form of the crystals remains. Rammelsberg has made various researches on this subject, and gives the following analyses. Silica. Alu- mina. Iron protx. Iron perx. Lime. Mag- nesia. Al- kali. Watr. Total. 1 45-8? 11-18 24-63 ... 1-50 0-28 6-72 9-82 100 2 39-48 10-31 15-66 894 I5-24a 1-70 ae? 100 3 60-63 23-0!> 4-21 1-28 0-91 9-12! 99-24 4 85-34) 1-58 1-67 2-66 1-70 5-47 98-42 (a) Carbonate of lime. Nos. 1 and 2 are green pseudomorphs, after augite, from the Fassa valley. Then* composition, especially the amount of alkali, is very remarkable. No. 3 is from a basalt vein in gneiss, near Bilin, where crystals of considerable size are changed into yellow, brown, or greenish-clayey masses, with a specific gravity of 2'216, and a composition like that of cimolite, the bases of the augite being almost entirely removed along with a portion of the silica. In many places, as in the Fassathal, the Breisgau, &c., a variety of steatite has been formed, the lime and protoxide of iron being removed, and the pro- portion of magnesia consequently increased, water being also added. In the vicinity of volcanos, as Vesuvius, the augite is often altered, probably from the action of acids, which have removed the bases and most of the alumina (IsTo. 4). In this process, the original black colour of the crystal first changes to greenish or bluish-grey, then to yellowish- white, which gradually encroaches on the dark kernel till the whole is converted into a white mass, porous and cellular within, but, as is common in similar pseudomorphs, firm and connected on the exterior. The relation between hornblende and augite, or rather between the two classes of mineral substances of which they are types, is highly interesting. The preceding descriptions show how near their che- mical pomposition and crystallization approach, and even the varia- tions in these points and external aspect correspond, or form parallel series. The faces of the crystals are either inclined to each other at 4 208 AUGITE HYPERSTHENE. [Hornblende angles that nearly agree, or if some forms occur in augite which have not been observed in hornblende, yet their occurrence is mathemati- cally possible according to the laws of crystallography. Hence it has sometimes been proposed to unite these minerals in one species. The investigations of Gustav Rose, however, prove that, notwithstanding the similarity of hornblende and augite, they still differ too widely to justify their union. Thus, the former contains more silica, and Bons- dorff has found in it to 1 per cent, of fluoric acid, which does not appear in the latter. Hornblende, too, is more fusible than augite, and ranges lower in specific gravity (hornblende from 2-931 to 3 '445 ; augite 3-195 3'525). Though both possess a cleavage parallel to their vertical prisms, yet these differ in angular dimensions, and both are never observed in the same individual. The cases in which G. Rose once thought that this occurred, he now believes were not sim- ple crystals, but unions (Verwachsungeri) of hornblende and augite crystals, each with its own cleavage. These minerals also occur in distinct geognostic positions. Hornblende in rocks containing quartz or free silica, and mostly with minerals that are neutral compounds of silica, as orthoclase and albite ; augite in rocks that do not contain free silica, and mostly with minerals that are not neutral silicates, as labradorite, olivine, and leucite. Hence there are two distinct series of massive or igneous rocks ; the hornblende series, including granite, syenite, diorite, diorite porphyry, and red porphyry ; and the augite series or hypersthene rock, gabbro, dolerite, nepheline rock, augite porphyry, and leucite porphyry. In some rare instances, these two minerals have been found together, either regularly conjoined or in distinct conditions. Thus, in the lava of Vesuvius, the basis contains imbedded crystals of augite and leucite, whilst fine acicular crystals of hornblende line the walls of drusy cavities, but never form part of the basis. The occurrence of hornblende with augite or olivine in some basalts or trachytes, requires further investigation. The Ura- lite, with the external form of augite, the internal structure of horn- blende, is considered by Rose as a pseudomorphic formation, augite changing into hornblende. It has been necessary to give these details, as in several recent mineralogical works the authority of G. Rose is adduced against the opinions he has so very ably supported. (Vide Rose, Reise nach dem Ural, Vol. ii. pp. 347 378.) 102. HTPEESTHENE, Hauy, Phillips, fyc. ; Paulite, Werner ; Prismatoidal Schiller-spar, Mohs. Isomorphous with augite ? ooP 87. Massive, in crystalline and granular aggregates, or disseminated. Cleavage, brachydiagonal very perfect, prismatic along ooP distinct, macrodiagonal very imperfect ; 3 Family. ,] BRONZITE, 209 H. = 6 ; G. 3 '3 3 "4. Opaque or translucent on thin edges. Lustre vitreous, inclining to resinous ; but metallic pearly on the principal cleavage planes. Colour pinchbeck-brown inclining to cop- per-red, pitch-black, and greyish-black. Streak greenish-grey. Not affected by acids. B.B. melts more or less easily to a greenish-black glass, often magnetic. Chem. com. analogous to augite, or generally (Mg, Fe) si Analyses. Silica. Alu- mina. Mag- nesia. Lime. Iron iMang. protox. 1 prot. Watr. Total. 1 54-25 2'25 14-00 1-50 24-50a trace 1-00 97'50 Klaproth, Labrador. 2 46-11 4-07 25-87 5-38 12-70 5-29 0-48 98-90 Muir, Paul's Island. 3 51-35 11-09 1-84 33-92 0-50 98-70 Do. Skye. 4 58-27 2-00 1896 14-42 6-34 99-99 Do. Baffin's Bay. 5 51-36 0-37 21-31 309 21-27 1-32 98-72 Damour, Labrador. 6 52-17 7 45-45 4-00 1133 18-00 20-00 24-33 10-73 ll-49a ... 1-00 99-23 99-27 Seybert, Wilmington Pa. Beck, Lake George N. Y. (a) Peroxide. Hypersthene differs chemically from augite in the small amount of lime. It forms a constituent of several rocks, as with labradorite of hypersthene rock ; and with labradorite and chlorite of diabase. It also occurs in the euphotide or gabbro. The finest specimens come from Paul's Island, the adjoining coast of Labrador, and Greenland. Hypersthene rock is common in many parts of Norway, at Elfdal in Sweden, where it is polished as an ornamental stone, in Skye in Scotland, and in Cornwall. It is less abundant in the Harz, the Thuringerwald, the Fichtelgebirge, and other parts of Germany. The American varieties Nos. 6, 7, are anomalous from the amount of lime, and perhaps only augite. 103. BROMZLTE, Karsten, Phillips; Diallage, Hauy / Hemiprismatic Schiller- spar, Mohs (in part.) Monoclinohedric, similar to augite ; C. = 72, ooP 86 (only ap- proximations, Mohs.) Occurs in indistinct imbedded crystals, or in granular aggregates. Cleavage, orthodiagonal very perfect ; pris- matic along ocP imperfect ; clinodiagoiial in traces. H. = 4-5 5, G. 3*2 3*5. Translucent, or only on the edges. Lustre resinous or vitreous ; on the more perfect cleavage planes, which are often slightly curved and fibrous, metallic-pearly or silky. Clove-brown to pinchbeck-brown, sometimes greenish or yellowish. Streak white. Not affected by acids. B.B. very difficultly fusible to a dark-brown or blackish -green glass. Chem. com. (7 Mg + Fe) & = 58'6 silica, 33 '0 niagnesia, and 8*4 iron protoxide. Analyses, next page. 210 DIALLAGE. [Hornblende 1 2 3 4 5 Silica. Alu- mina. Mag- nesia. Lime. Iron protox. Mangan. protox. Watr. Total. 57-19 56-84 55-84 5(r41 58-00 0-70 2-07 1-09 l"-33 32-67 2968 30-37 31-50 29'66 1-30 2-20 7-46 8-46 10-78 6-56 10-14 0-35 0-62 3 : 30 1-00 0-63 0-22 1-80 2-38 100-30 Kohler, Stempel. 101 MX5 | Do. Ultenthal, Tyrol. 99-88 Regnault, Do. 100-15 Do. Gulsen, Styria. 100-13 v. Kobell, Greenland. Occurs in serpentine near Kraubat in Styria, and in Baireuth; in basalt (with olivine, No. 1) near Marburg, and near Sontra, in Hessia. No. 5, from Ujardlersoat, in Greenland, was considered anthophyllite. It is distinguished from diallage and schiller-spar by its action before the blowpipe, and from the latter also by its greater hardness and specific gravity. 104, DIALLAGE, v. Kobell, Hauy ; Prismatic Schiller-spar, Mohs, (in part.) Cleavage very perfect in one direction, imperfect in a second, and traces only in others. H. = 4 ; G. = 3-2 3'3. Translucent in thin plates. Lustre resinous or vitreous, but metallic-pearly, or silky on the cleavage planes. Colour light-grey, brownish-grey, or pinchbeck- brown. Streak white. Not affected by acids. B.B. melts rather easily to a greyish or greenish enamel. Chem. com. (3 c a + Mg + Fe ) si, with 54*6 silica (with alumina), 21'2 lime, 15'1 magnesia, and 9'1 iron protoxide. Analyses. Silica. Alu- mina. Mag- nesia. Lime. Iron protox. Mangan protox. Watr. Total. 1 52-89 2-70 17'68 17-40 r- * v 8-41 1-06 100- 14 s Kohler, Baste,* (mof 2.) 2 51-34 4-39 15-69 18-28 8-23 2-11 100-04 Do. Salzburg. 3 53-20 247 1491 19-0!) 8-67 0-38 177 100-49 Do. Prato, Florence. 4 51-25 3-98 22-88 11-18 6-75 332 99'3o Regnault, Traunstein. \ 5 50-05 2-58 17-24 15-(53 11-98 2-13 99- Berzelius, assuming the iron to Family."] WOLLASTOXITE. 213 be the protoxide, makes it 3 Ma 2 si + 2 Fe st, mixed with some car- bonate of manganese protoxide. Found at Sterling in New Jersey. The last two silicates of manganese might be classed in the family of metallic stones, or near to olivine. 108. WOLLASTONITE, Hauy ; Tabular-spar, Phillips ; Schaalstein, Werner ; Tafelspath, Stutz ; Prismatic Augite-spar, Mohs. Monoclinohedric ; C = 84 40', ooP 140, according to V. Kobell ; lengthened along the orthodiagonal ; very rarely freely crystallized, mostly in imperfectly-formed, broad prismatic or laminar masses. Cleavage, along OP and ooPoo , or basal and orthodiagonal, perfect, but planes uneven or rough. H. = 5 ; G. = 2'7 2*9. Translu- cent. Lustre vitreous, and rather pearly on the cleavage-planes. Colourless or white, but generally inclining to grey, yellow, red, or brown. Streak white. Phosphoresces with heat or friction. Gela- tinizes in hydrochloric acid. BB. difficultly fusible to a semitrans- parent glass. Chcm. com. da si, with 52*5 silica, and 47 '5 lime. Analyses. Silica. Lime. Mag- Iron ne^ia. perox Watr. Total. 1 53-1 45-1 1-8 loo Beudant, Cziklowa, Bannat. 9, 51-60 46-41 ... trace. ... a 99-12 H. Rose, Perhoniemi, Finnland. 3 4 52-58 1 44-45 0'68 0'13 52-50 46-33 ... 170 0-99 99-83 100-58 Bonnsdorff, Skrabbole, Do. Hisinger, Karelen. 51-0 46-0 trace. 1-3 1-0 99'3 Seybert, Willsborough, N. York. 6 7 51-50 51-67 45-45 47-00 0-55 1-35 2'00 99-50 100-02 v. Kobell, Capo di Bove, Rome. Vanuxem, Willsborough. 8 51-90 47-55 025 ... 99-70 Beck, Diana, N. York. 9 10 50-60 50-72 47-21 43-80 ... 1 0-14& 0'83 ! (C85c '." d 97-95 99-31 Palander, Pargas. Weidling, Gockum, Upland. 11 12 54-00 49-73 30-79| 2-59 4079 j ... trace. 0'31d 5'43e 98-36 .../I 98-65 Walker, Corstorphine Hills. Walchner, slag from furnace. (a) + I'll mixture of asbestus; (6) with alumina; (c) protoxide; (d) +0-33 mangan- ese protoxide and 273 carbonate of lime; () + 5-55 soda and trace of alumina ; (/) + 7-82 alumina. Hauy described this mineral as rhombic, and Phillips as triclino- hedric. Mr Brooke and v. Kobell have shown that the crystals from Capo di Bove are monoclinohedric like those of augite, thus corres- ponding to its chemical composition, which, as Frankenheim states, is an augite of the simplest kind. Wollastonite occurs chiefly in granular limestone, as in the Bannat, Finnland, Sweden, North America, and Ceylon. Crystallised chiefly in lava at Capo di Bove, and in blocks ejected by Vesuvius. It is .found also in clinkstone in the Castle rock at Edinburgh, along with prehiu'te. No. 11, a similar mineral from the greenstone of Corstor- phine Hill, is probably a distinct species. It is white, fibrous, does not effervesce with acids, and B.B. fuses with intumescence to a hard 214 ACHMITE SOKDAWALITE. [Hornblende white enamel. Wollastonite has been formed chemically ; and No. 12 is a similar substance from the slags of the iron furnaces at Ober- weiler in Baden. Dr Thomson gave the same name to a distinct mineral from Kil- syth. 110. ACHMITE, Berzelius, Phillips, Beudant, -c. ; Paratomous Augite-spar, Mohs. Monoclinohedric ; isomorphous with augite. The crystals are long prisms formed by coP . ocPco . ( coPoo ), and terminating very acutely in 4P. Cleavage like augite, or prismatic along ooP (87), orthodiagonal and clinodiagonal ; H. = 6 6'5 ; G. = 3 '5 3*6 (3'43, in powder 3 '53, Ram.). Nearly opaque; lustre vitreous; colour brownish or greenish-black, occasionally spotted. Streak greenish-grey. Imperfectly soluble in acids. B.B. fuses easily to a black magnetic glass. With borax shows reaction for iron, with soda on platina wire for manganese. Chem. com. p'e 2 si 3 + 2 N a si 3 = 55'6 silica, 32 iron peroxide, and 12'4 soda. Analyses. K -| P SS. Mang. perox. Soda. Lime. Mag- nesia. Loss by heat. Total. 1 54-27 2 55-25 3 52-02 4 54-13 34-44a 31 25 28-08& 34-44 1-08 3-49 9-74 10-40 13-33 072 0-88 : 50 1-88 V 68c 100-33 9870 98-98 Strom, Eger. Berzelius, Do. Lehunt, Do. Rammelsberg, Do. (a) With manganese peroxide ; (&) protoxide; (c) alumina. Rammelsberg fourid that achmite contains no protoxide of iron. Strom and Berzelius observed traces of titanic acid, von Kobell 3*25 per cent., and Rammelsberg 3'1 per cent., but mixed with silica, and probably from a mixture of titanic-iron (iserine). Achmite occurs, though rarely, imbedded in quartz and felspar in granite at Eger, and also it is said in syenite at Kless near Porsgrund, in Norway. 111. SORDAWALITE, Nordenskiold. Massive. Fracture conchoidal ; brittle ; H. = 4 4-5. G. = 2'55 2-62. Opaque ; resinous or vitreous. Brownish -black or black- ish-green. Streak liver-brown. In closed tube gives water. B.B. fuses to a black globule ; with borax and salt of phosphorus reaction for iron and silica. Chem. com. jjj si 2 + 4 it si + 2 H ; the silica including the phosphoric acid, and R being equal parts of iron prot- oxide and magnesia. Nordenskiold found 49 '40 silica, 13*80 alumina, 18-17 iron protoxide, 10*67 magnesia, 2-68 phosphoric acid, 4'38 wa- Family.'} KROKYDOLITE PYRALLOLITE . 215 ter (= 99 '10). Berzelius considers it a mixture of phosphate of magnesia, with a bisilicate. It occurs in thin veins on trap at Sorda- wala in Finnland. 112. KROKYDOLITE, Hausmann, Phillips, Mohs; Blue ironstone, Klaproth. Microcrystalline, in plates of very fine, easily separable but tough, elastic fibres. H. = 4 ; G. = 3 '2 3'3. Translucent ; silky, or dull. Colour indigo blue ; streak lavender blue. In closed tube yields water ; in open tube becomes reddish-brown. B.B. fuses easily to a black magnetic glass. With salt of phosphorus shows reaction for iron, and leaves silica. Chem. com. 3 Fe si B = Na + 5- Mg. Analyses. it si 2 + 2 H, where 1 2 Silica. Iron prot. Mang. perox. Mag- nesia. Lime. Soda. Water. Total. 50-81 51-G4 33-88 34-38 0-17 0-02 2-32 2'64 0-02 0-05 7-03 7-11 5-o8 4-01 9981 99-85 Stromeyer. Do. No. 1 is an asbestiform, No. 2 a fibrous variety, both from Orange river in South Africa. It also occurs in the zircon syenite of Stavern, Norway, and in Greenland. The fibrous Siderite, from the gypsum at Golling in Salzburg, seems also krokydolite. Berzelius points out its similarity in composition to achmite. 113. PYRALLOLITE, Nordenskiold, Phillips, fyc. ; Tetartoprismatic Picrosmine-steatite, Mohs. Triclinohedric ; prismatic combination of oo'P' . P . ooPoo ; with ooF to oo'P = 94 36' ; and ooPco to ooP' = 130 33', and to oo'P = 144 3'. Usually massive, columnar, or granular. Cleavage, right and left hemiprismatic, also macrodiagonal distinct. Fracture uneven, splintery ; rather brittle. H. = 3 '5 4 ; G. = 2'55 2'60. Opaque or translucent on the edges. Resinous, on the cleavage planes pearly. Greenish-white, asparagus-green, and yellowish-grey. In the closed tube gives out water ; B.B. becomes black, then white, and fuses with much difficulty on thin edges to a white enamel. Chem. com. proba- bly silicate of magnesia with a little silicate of lime and water. Nor- denskiold found in it 56*62 silica, 23'38 magnesia, 5'58 lime, 99 manganese protoxide, 0'09 iron peroxide, 3'38 alumina, 3 58 water, .6'38 bituminous matter and loss (= 100). Occurs in granular lime- stone with green augite at Storgard in Pargas, Finnland. Exposed to the light and air, it gradually becomes pale and dull. 216 praABGiLLiTE KARPHOLiTE BABiXGTOXiTE. [Hornblende 114. PTRARGLLLITE, Nordenskiold, Phillips, Mohs. Probably rhombic, but the crystals indistinct and imbedded. Also massive. Cleavage not observable. Fracture uneven. H. = 3*5 ; G. = 2-5. Translucent on the edges, or opaque. Dull resinous lustre. Greyish or blackish-blue, also liver-brown or brick-red. Soluble in hydrochloric acid. B.B. infusible alone, slowly with borax or salt of phosphorus. Chem. com. 2 i si 2 + RSI + 6 H ; or, by Xorden- skibld's analysis, 43*93 silica, 28'93 alumina, 5-30 iron protoxide, 2*90 magnesia with manganese, T05 potash, 1-85 soda, 15-47 water (= 94*43). Occurs at Helsingfors in Finnland in granite. 115. KABPHOLTTE, Werner, Hauy, Phillips, Mohs. Only found in radiating or stellated masses of fine acicular or short capillary crystals. H. = 5 5*5 ; G. = 2'935. Translucent, silky, and straw-yellow, inclining to wax-yellow. Streak colourless. In the closed tube yields water with traces of fluorine. B.B. intumesces and forms an opaque brown glass. With fluxes shows reaction for manganese. Scarcely affected by acids. Chem. com. i s"i -I- Mn si + 2 H. Analyses. U Silica.* AIu - ! Man 8- |mina.S perox. ^Lime.| Water. Fluoric acid. Total I 1 ! 37-53 ! 25-47 I 18-33 i 2 I 36 15 ! 28-67 19*16 6-2? 1 ~ 1 ll-3fi 2-290 ; 0-27 10-78 1-47 99-96 98-79 Steinmann. Stromeyer. (a) Protoxide. Only found at Schlakenwald in Bohemia, in a quartzose granite with fluor spar. The fluoric acid is perhaps accidental ; or, according to Berzelius, combines with the silicate of manganese. In external aspect it resembles some of the zeolites, but differs in its action with acids. 116. BABINGTOXITE, Levy, Phittips, Sfc. ; Axotomous Augite-spar, Mohs. Triclinohedric; ooPx (M) : ocPx (f)= 112 3(K; ocP'(^): x'P (^)= 904(y ; OP(P):-| "^ / 1 45-25 2 58 3 49-2 36-50 32 36-2 2-75 2 0-5 trace !!! 14-00 7 14-0 98-50 99 99-9 Klaproth, Rochlitz, Saxony.^ v ** > ^; Do. Oemrichsberg, Silesia. Zellner. Buchberge, Landshut. 4 43-00 40-25 0-48 ... 0-47 15-50 99-70 Dumenil, Clausthal. 5 49-75 6 43-46 29-88 41-486 6-61 6'35 0-43a l-20c 5-48 13-49 99-97 100 Rammelsberg, Zorge, Harz. Do. Schlackenwalde. (a) + 1-47 magnesia; (6) with peroxide of iron and manganese ; (c) + 0'37 soda. No. 1 is named Carnat by Breithaupt, from its fine red colour. No. 2 is a so-called crystallised lithomarge, probably a pseudomorph 226 MILOSCHIN KEROLITE. \Clay of felspar found in a decomposed porphyry, near Flachenseifen. No. 4 is a white phosphorescing variety from a mine in the Harz, G. = 1-59. No. 5 is green, G. = 3 '086. No. 6 white and radiated ; yielded water in the closed tube, and B.B. emitted a strong light and became hard without fusing. The Myelin of Breithaupt, or Talksteinmark, from Rochlitz in Saxony, is reniform or curved lamellar ; pale-yellow or flesh-red. B.B. infusible, but becomes blue with cobalt solution. According to Kersten, it contains 37*62 silica, 60*50 alumina, 0*82 magnesia, and 0*63 peroxide of manganese, with a trace of iron peroxide (== 99 -57). It is thus nearly a compact cyanite or andalusite ; but Breithaupt finds in it 5 per cent, water. The Melopsite of Breithaupt, yellowish or greenish-white, from Neudeck in Bohemia, seems impure. It con- sists, according to Plattner, of silica, alumina, some magnesia and iron peroxide, with water and traces of ammonia. 135. MILOSCHIN, v. Herder; Serbian, Breithaupt. Compact. Fracture conchoidal and smooth, or earthy ; H. = 2 ; G. = 2*13. Colour indigo-blue to celadine-green. Adheres to the tongue and crackles in water. B.B infusible. Partially soluble in hydrochloric acid. Chem. com. (i, Cr) si + 3 H. Analysis by Kersteu ; 27*50 silica, 45-01 alumina, 3 -61 chrome oxide, 0*30 lime, 0*20 magnesia, 23*30 water, with traces of potash and iron peroxide, (= 99*92). Occurs at Rudniak in Servia, 136. KEROLITE, Breithaupt, Massive reniform. Fracture uneven, or smooth conchoidal, or seldom splintery. Rather brittle ; H. = 2 3 ; G. = 2 -3 2*4. Translucent ; dull resinous lustre. Colour white, inclining to grey, yellow, green, or red. Feels greasy, but does not adhere to the tongue. In the closed tube yields water, and becomes black. B.B. is infusible, but colours the flame pale-red. Analyses. Silha. Alu- mina. Mag- nesia. Iron prot. Watr. Total. 1 3795 2 47-13 3 53-5 4 46-96 12-18 2-57 09 18-02 36-13 28'6 31-26 2 : 92 31-00 11-50 16-4 21-22 99-15 100-25 99-4 99-44 Maak, Frankenstein, Silesia. Melling, Zoblitz, Saxony. Delesse, Do. ? (G. = 2-335). Kuhn, Silesia. Each analysis leads to a different result, and the minerals are pro- bably distinct species. The characters above refer especially to No. 1. No. 2 occurs in serpentine, and, except the alumina, nearly agrees with this rock in composition. Family.] AGALMATOLITE SOAPSTONE. 227 137. AGALMATOLITE, v.Leonhard; Figure-stone, Phillips ; Pagodite, Bildstein, Werner; Talc-glaphique, Hauy. Massive, imperfectly slaty. Fracture splintery. Rather sectile. H. = 2 3 ; G. = 2-8 2'9. Translucent or only on the edges. Lustre dull or glimmering. Colour various shades of green, grey, red, and yellow. Feels somewhat greasy, but does not adhere to the tongue. B.B. burns white and fuses slightly on very thin edges. Not decomposed by salt of phosphorus. Soluble in warm sulphuric acid. Chem. com. 4 7*6 potash, and 4-4 water. + k si 3 + 3 H = 55 silica, 33 '1 alumina, Analyses. Silica. Alumina. Iron per ox. Lime. Potash. Water. Total. 1 56-0 2 54-50 3 55-0 4 55-50 5 51-50 6 49-82 7 72-40 8 54'0 29-0 34-00 330 3000 32-50 29-59 24-54 26-5 1-0 0-75 0-5 1 00 a 1-756 1-50 2-85 1-5 2-0 175 3-00 6-00 (c) 70 6-25 7-0 6-25 6-00 6-80 5-5 5-0 400 3-0 5-50 5-13 5-50 12*6 100 99-50 98-5 100 100 99-21 99-79 99-5 Vauquelin, China. Klaproth, Do. Do. Nagyag. John, China. - Do. Saxony. Thomson, China. Lychnell, Do. Klaproth, Argentiera. (a) + trace of manganese peroxide; (6) + 0'12 manganese peroxide ; (c) trace of magnesia- No. 7 was probably some other mineral, and many substances are named agalmatblite which are in reality distinct. It occurs especially in China, where it is cut into various works of art. It is also found at Nagyag in Hungary, and in beds in mica slate on the Ochsenkopf in Saxony. Also, it is said, in Wales. The Cimolite of Klaproth (No. 8 above) is a pure white clay from the island of Argentiera, and probably a mere product of decomposition of trachyte or other felspar rock. It is also found in Milo, and used for cleaning cloth. 138. SOAPSTONE, Phillips ; Seifenstein, Werner; Pierre de Savon, Hauy. Massive. Sectile and very soft. H. = 1*5 ; G. = 2-26. Colour white, or light grey, yellow, and reddish-brown. Streak shining ; feels greasy, and writes feebly. Does not adhere to the tongue. In the closed tube yields water. B.B. fuses to a colourless porous glass. Soluble in sulphuric acid. Analyses. Silica. Alumina. Magnesia. Iron perox. Lime. "Water. Total. ll 45-00 2 46-8 9-25 8-0 24-7 33-3 1-00 0-4 ...a 0-7 18-00 11-0 98-75 100-2 Klaproth, Cornwall. Svanberg, Do. 3 50-89 9-40 26-52 2-06 0-78 10-50 Il00-15 Do. Svardsjo". (a) + 0-75 potash. The soapstone is found at the Lizard Point (No. 1) in Cornwall in veins in serpentine, and also at St Clear. No. 3, from Dalarne in 228 PIPESTONE MEERSCHAUM. \_Clay Sweden, seems the same mineral. The difference in the amount of water arises from Klaproth's specimen not being dried before analysis. This mineral is easily distinguished from steatite by its action before the blowpipe. 139. PIPESTONE, Thomson. Compact ; fracture earthy ; sectile ; H. = 1-5 ; G. = 2-6; opaque, dull, and greyish-blue or black. B.B. infusible. Analyses. 2 Silica. Alu- mina. Iron perox. Mag- nesia. Lime. Soda. Watr. Total. 56-11 48-2 17-31 28-2 6-96 5-0 0-20 6-0 2-17 26a 12-48 4-58 8-4 99-81 99-0 Thomson, Oregon. Jackson, Catlinite. (a) Carbonate of lime + 0'6 manganese peroxide. No. 2, the Catlinite of Jackson, from the Coteau de Praires, is of a red colour, and highly prized by the Indians as a material for pipes. 140. MEERSCHAUM, Werner, Jameson; Earthy Carbonate of Magnesia. Compact ; fracture flat conchoidal and fine earthy; sectile ; H. = 2 2-5 ; G. = 0-8 1-0 (when moist nearly 2). Opaque ; dull, streak slightly shining ; colour yellowish and greyish-white ; feels rather greasy, and adheres strongly to the tongue ; in the closed tube gives out water, and becomes black. B.B. contracts, becomes hard, and fuses on the edges to a. white enamel. With solution of cobalt be- comes pale-red. Soluble in hydrochloric acid, leaving slimy flakes of silica. Chem. com. Mg 2 s\ 3 + 2n, according to Lychnell's analy- sis of the mineral dried in vacuum over sulphuric acid ; others give twice the amount of water, or 4 H. Analyses. Silica. Mag- nesia. Alu- mina. Iron perox. Lime. Watr. Total. 1 50-50 17-25 0-50a 25-00 98-25 Klaproth, Asia Minor. 2 50-0 25-0 ... ... 25-0 100 Berthier, Do. 3 60-87 27-80 0-096 11-29 100-05 Lychnell, Do. 4 53-8 23-8 1*8 ... 20-0 98-8 Berthier, Madrid. 5 54-0 24-0 1-4 ... 20-0 99-4 Do. Coulommiers. 8 48-00 20-06 12-40 19-60 100-06 v. K obeli, Greece. 7 55-00 28-00 1 20 1-40 1-Olc 10-35 98-98 Damour, Morocco. 8 51-57 33-90 0-16 0-57d 11-83 99-58 Berlin, (Aphrodite). (a) + 5-00 carbonic acid ; (&) with iron peroxide ; (c) + 0-52 potash, and 1-50 sand ; (d) protoxide + 1'55 manganese protoxide. Klaproth's analysis (No. 1) is remarkable for the carbonic acid. Von Kobell thinks the iron in No. 6, a yellowish-red variety, was mixed as a hydrate. Family.'] PIMELITE DERMATIN RETINALITE. Meerschaum comes chiefly from Kiltschik near Konie in Asia Minor. It also occurs near Thebes, and in other parts of Greece, along with semiopal ; in Spain it forms beds in marl at Valecas near Madrid and near Toledo ; and at Pinheiro in Portugal, in syenite. At Hrubschitz in Moravia it occurs in serpentine. The so-called meerschaum from the Taberge and Sala in Sweden, is shown by Ber- lin to be serpentine. That from Langsbanshytta in Wermeland (No. 8), he makes a distinct species named Aphrodite, G. = 2*21 ; but it agrees in most points with meerschaum. This substance is chiefly used in forming heads for tobacco pipes. 141. PIMELITE, Karsten. Massive, fracture conchoidal, H. =: 2*5 ; G = 2-232-3. Trans- lucent, dull resinous ; colour apple-green, streak greenish-white. Feels greasy, but does not adhere to the tongue. According to Ber- zelius, gives water in the closed tube and becomes black. Melts to a slag only on thin edges. With borax, shows reaction for nickel. Chem. com. unknown. The pimelite or chrysoprase-earth, analysed by Klaproth, was apparently a mixture. In another from Franken- stein in Silesia, Schmidt found 54-63 silica, 32-66 nickel oxide, 5'89 magnesia, 0'16 lime, T13 iron protoxide, 0'30 alumina, and 5-23 water. It felt meagre and adhered to the tongue ; G. = 1-458. The Razoumoffskin of John is by some united to pimelite, but the variety from Kosemutz in Silesia, analysed by Zellner, gave 54-50 silica, 27-25 alumina, 2-00 lime, 0'37 magnesia, O25 iron protoxide, and 14-25 water (= 98'62). This gives i & 3 + 3n, and it is probably dis- tinct. 142. DERMATIN, Breithaupt. Compact or reniform. H. = 2'5 ; G. = 2-136. Kesinous ; colour blackish-green ; streak yellowish-white. Does not adhere to the tongue. When breathed on, has an argillaceous smell. B.B. cracks and becomes black. Chem. com. (Mg, Fe) si + 2k. Analyses. 1 2 Silica. Mag- nesia. Iron prot. Mang. perox Alu- lllilKl. Lime. Soda. Water& carb. ac. Sulph. acid. Total. 35-80 40-17 2370 19-33 11-33 14-00 2-25 1-17 0-42 0-83 0-83 0-83 0-50 1-33 25-20 22-00 40-3 100-03 100-09 Ficinus. Do. Occurs at Waldheim in Saxony in serpentine. 143. RETINALITE, Thomson. Massive and resinous-looking. Fracture splintery ; H. = 3*5 ; G. = 2-493. Translucent, resinous, and brownish-yellow. B.B. 230 GARNET. [Garnet becomes white and friable without fusing. Forms with borax a co- lourless glass. Chem. com. very near u g s s'i 2 + 2 Na si + 7k. Thomson found 40'55 silica, 18*36 magnesia, 18'83 soda, O62 iron peroxide, O30 alumina, and 2OOO water (= 99'16). From Gran- ville in Upper Canada. X. FAMILY. GARNET. 144. GARNET, Phillips, frc.; Granat, Werner, S$c.; Grenat, Hauy ; Dodecahedral Garnet, Mohs, Jameson. Tesseral ; most common forms coO (like fig. 3 above), and 2O2 (fig. 6). These are often combined, and also 3O : |, 40, and also others (figs. 21 and 22 above). The crystals are either imbedded singly, or are attached and combined in druses. Also in granular or compact masses. Cleavage dodecahedral, but very imperfect, and often not observable. Fracture conchoidal, or uneven and splintery. H. = 6-5 7-5 ; G. = 3 '5 4'3. Pellucid in all degrees. Lustre vitreous or resinous. Rarely colourless or white ; generally red, brown, black, green, or yellow, according to their composition. B.B. in general fuse easily to a glass, black or grey, in those containing much iron, green or brown in the others, and often magnetic. Im- perfectly soluble in hydrochloric acid ; some wholly, after long diges- tion, leaving the silica in powder. After strong ignition the more calcareous varieties are easily decomposed and gelatinize ; the others must first be almost or entirely fused. Chem. com. exceedingly va- riable, but generally R 3 si 2 -f- B," si. They then form two series, ac- cording as B is chiefly alumina or chiefly iron peroxide : and these are again divided according as R is more especially lime, iron prot- oxide, magnesia, or similar bases. Analysis, however, shows that these varieties are rarely pure, but are mixed with or pass into each other. Analyses, next page. This table contains only a mere selection from the very numerous analyses of this mineral, so highly interesting from its bearing on the doctrine of isomorphism. It shows that no one of the bases is con- stant in its occurrence, but that any one of them may be replaced in whole or part by other elements. The silica also in some seems to be replaced in part by alumina. Hence many varieties of this mi- neral have been distinguished partly from chemical, partly from phy- sical characters, the more important being the following : (1.) Almandine, or noble garnet, is columbine-red inclining to violet, blood-red, or reddish-brown ; streak white ; transparent or Family.'] GABNET. 231 Silica. Alu- mina. Iron perox Iron prot. Mang. protox. Lime. Mag- nesia. Total. 1 3962 19-30 ... 34-05 0-85 3-28 2-00 99-10 Karsten, Greiner. 2 39-85 20-60 24-85 0-46 3-51 993 9!)-20 Do. Greenland. 3 39-12 21-08 6-00 27-28 0-80 5-76 100-04 v. Kobell, Greiner. 4 40-56 20-61 5-00 32-70 1-47 UK) -34 Do. Hungary. 5 38-25 19-35 7'33 0-50 3175 2 : 40 9958 Karsten, Wilui river. 6 40 55 20-10 5-00 0-48 34-86 1110-99 Trolle-Wachtmeister, Do. 7 39-60 21-20 ... 2"-00 3-15 3-2-30 ... 9825 Do. Tellemark. 8 36-86 24-19 37-15 ... 98-20 Croft, Slatoust. 9 38-80 21-20 6 : 50 ... ... 31-25 ... 9775 K la proth, Ceylon. 10 41-87 20-57 3-93 3394 0-39a 10070 Arfvedson, Malsjo. 11 41-24 24-08 7-02 0-926 24-76 100-1 (0 Nordenskiold, Kimito. 12 37-82 1970 5-95 0-15 31-35 4'15 99-12 Karsten, St Gotthardt. 13 39-93 13-45 10-95 3-55 1-40 31-66 ... 100-94 Tr.-Wachtmeister, Vesuvius. 14 42-45 22-47 9-29 6-27 6-53 13-43 100-44 Do. Arendal. 15 36-73 2-78 25 : 83 2179 12-44 99-57 Bredberg, Sala. 16 35-10 29-10 7 '08 2691 ...c 99-17 Tr.-Wach., Langsbanshytta. 17 38 12 7*-32 19-42 3-30 31-65 ...d 100-00 Do. Hesselkulla, green. 18 37-99 2-71 28-52 ... 0-62 30-74 ... 100-58 Do. Do. brown. 19 40-20 6-95 20-50 4-00 29-48 101-13 Do. Arendal. 20 33-64 ... 1 30-00 302 29-21 a 100-22 Do. Altenau, Harz. 21 38-00 600 28-06 29-00 ... 101-06 Seybert, Lake Champlain, 22 37-00 5-00 18-50 6 V 25/ 30-00 96-75 Rose, Drammen. 23 33 72 7'97 17-64 1670 22-88 96-91 Thomson, Franklin, N. A. 24 35-50 26-IK) ... 0-40/ 32-50 ... 100-40 Klaproth, Frascati. 25 34-60 4-55 28-15 ... 31-80 6-65 9975 Karsten, Do. 26 36-45 2-06 29-48 o"28 30-76 0-ORr/ 100 051 Ebelmen, Beaujeux. 27 37-60 14-40 13-35 .!! ... 27-80 6-55/i 10070 Richardson, Norway. Dhrome perox. 28 37-11 5-88 2-44 22-54 30-34 MOfc 100-42 Komonen, Bissersk. 29 36-93 l' : 96 21-84 31-63 1-54J 99-58 Erdmann, Ural. 30 35-57 6-25i 23-45 3322 98-49 Damour, Do. (a) With manganese protoxide; (6) with magnesia + 1 98 volatile and loss; (c) + 0'98 potash ; (d) + 0-18 carbonic acid and loss ; (e) + 2-35 potash; (/) peroxide; (ff) + 0'96 loss by heat ; (h) + 1-00 water ; (*') with iron peroxide; (ft) + 1-01 water; (I) trace of copper. translucent ; sometimes magnetic. Analyses, No. 1-4, and hence an iron-alumina garnet with special composition, Fe 3 si 2 -I- AI si, with 37 silica, 20'1 alumina, and 42'9 iron protoxide. It is common in mica, talc, chlorite, and hornblende slates, also in gneiss and granite, in distinct crystals or grains often very small. Occasionally it forms subordinate beds, and more rarely veins. The finest specimens are brought from Pegu, Ceylon, and the East ; others from Brazil, and a blood-red variety from Greenland. Large crystals, but inferior in beauty and transparency, occur at Fahlim, Arendal, Kongsberg, the Tyrol, the Ural, and in North America. It is common in the mica- slates of Perth, Inverness, and Zetland. It is used as an ornamental stone. The Tyte-Quarner, or Norwegian millstones, found at Selboe, is a mica-slate with numerous minute garnets ; and similar millstones of excellent quality are procured on the Simplon. (2.) Lime-alumina-garnets, consisting essentially of Ca 3 si 2 4- Al si with 40'7 silica, 22'5 alumina, and 36'8 lime. To these belong (a) The Grossular, pale gooseberry-green, sometimes greenish- white, to mountain or olive green, and translucent. It occurs with 232 GARNET. [Garnet Vesuvian in a serpentine-like rock on the Wilni river, Siberia ; white and massive in chlorite-slate in the Ural, and white crystallized at Tellemark, Norway. Analyses, Nos. 5-8. (6) Cinnamon-stone, Hessonite, or Kaneelstein, is usually hyacinth- red to honey or orange -yellow, and transparent or translucent. It is found in gneiss or in loose grains in Ceylon (No. 9), and Berzelius discovered a similar mineral (No. 10), in limestone in Wermeland. The Romanzowitc (No. 11), from limestone at Kimito, Finnland, is also similar, part of the iron being probably protoxide. When po- lished, this variety is often named Hyacinth. (c) Common lime-garnet, of various, more or less pure, red, brown, yellow, or green colours, and with part at least of the alumina re- placed by iron peroxide. Analyses, Nos. 12, 13. This is the most abundant of the lime- alumina-garnets, occurring in the crystalline rocks in single crystals or in druses, and also in subordinate beds or veins, as in Piemont, the Ural at Slatoust, and in North America ; also on Vesuvius in ejected blocks. (3.) Magnesia-garnet, in which a is chiefly magnesia, opaque, lustre rather resinous ; colour coal-black ; streak dark-grey ; G. = 3'157. B,B. fuses easily with bright light, and effervescing to a dark greyish-green non-magnetic globule, and is not affected by acids. It is found with calc-spar at Arendal, No. 14. (4.) Iron garnets, consisting essentially of ca 3 si 2 + PC & with 36*2 silica, 31 '1 iron peroxide, and 33 '6 lime. G. Rose states this variety to be more difficultly fusible and more easily soluble in hydrochloric acid than the others. (a) Common iron-garnet, crystallized, granular, or compact. Subtranslucent or opaque, green, brown, yellow, or black, with white, grey, or yellow streak. Analyses Nos. 15 23, No. 16 being the Rothoffite, distinguished by the amount of manganese, and No. 22 the Allochroite. It occurs in the crystalline, or rarely in the transition, rocks, forming subordinate beds either alone, or more frequently mixed with other silicates, or with calc-spar. It is often associated with magnetic or other ores of iron, when it promotes their fusibility and productiveness, and in some places is intentionally mixed with them, and named " green iron-ore." It is more rare in veins, or im- bedded as in granular limestone. Fine specimens occur in Sweden and at Arendal. (6) Melanite, black, opaque, in thin splinters translucent. Streak grey, slightly magnetic. Analyses Nos. 24, 25, 26. Klaproth makes the iron the proto-peroxide (= 24"25), which seems confirmed by the colour and magnetism of the mineral. It is found in the peperino at Albano, in loose crystals near Frascati, in the ejected Family.'} PYROPE. 233 blocks on Vesuvius, and at Beaujeux in the Khone department, France. Also massive in the magnetic iron ore at Svappavara in Torneo-Lapp- mark. The Pyreneite found in limestone in the Pic d'Ereslids near Bareges in the Pyrenees, seems also melanite. (c.) Cotophonite, yellowish-brown to pitch-black, also honey-yel- low or hyacinth-red ; streak white, lustre resinous. G. = 3*43. It occurs either in crystals with calc-spar, or in large coarse or fine granular masses in the magnetic iron-ore of Arendal. Analysis No. 27. (5.) Uwarowite, or chrome -garnet, occurs in emerald-green dode- cahedral crystals, with greenish- white streak, vitreous lustre, and translucent or only on the edges. Fracture imperfect conchoidal ; G. = 3-418 ; H. = 7'5. B.B. is infusible alone, but with borax forms a clear chrome-green glass. Analyses Nos. 28, 29, 30. It is found with chromate of iron at Bissersk and Kyschtimsk in the Ural. It has been considered a distinct species, but may be included under garnet. 145. PYROPE, Karsten, Phillips; Almandine, Beudant ; Hexahedral Garnet, Mohs. Very rarely crystallized, in indistinct hexahedrons with rough con- vex faces. Generally in roundish grains, loose or imbedded. Cleav- age, not perceptible ; fracture conchoidal ; H. = 7 '5 ; G. = 3*7 3-8. Transparent or translucent ; lustre vitreous ; colour dark-hya- cinth to blood-red. B.B. becomes black and opaque, but regains its colour and transparency on cooling ; fuses with diificulty to a black glass ; with borax shows reaction for chrome ; not soluble in acids, but partially after fusion. Chem. com. uncertain. Analyses. Silica. Alu- mina. Iron perox. Mag- nesia. Lime. Mang. perox. Chrmic acid. Total. 1 40-00 2 4370 28-50 22-40 16-50 ll-48a 10-00 5-60 3-50 6-72 0-25 3-68a 2-00 7'68 100-75 1(10-66 Klapioth, Bohemia. Trolle-Wachtmeister, Mero- 3 43-00 22-26 8-74 18-55 5-68 1-806 100-36 v. Kobell, Do. [nitz. 4 42-80 28-65 931 10-67 4-78 0-25a trace b 96-46 Connel, Elie in Fife. {a) Protoxide; (6) chromium oxide. Some consider the chrome in the pyrope as the acid, others as the peroxide ; and Rammelsberg in No. 2 changes it to 6'52 chromate of chrome-peroxide (chromsaures Chromoxyd). Its very variable amount in the Bohemian varieties, and the mere trace in that from Elie, show it to be probably an incidental mixture (chromate of iron). Connel's analysis gives nearly R si -Kit *>i, neglecting the loss ; but if it was magnesia, then this will not apply. Naumann, from anal. u 234 HELVINE. [Garnet No. 3, proposes R 3 si 2 + jii si, or the same with garnet, 3 R being 2 atoms magnesia, atom iron protoxide, and \ atom lime. Apjohn stated that the pyrope contains 3 per cent, yttria, which has not been confirmed. Occurs in serpentine at Zoblitz in Saxony. In loose blocks of claystone near Meronitz, and more frequently in dispersed grains, as on the southern declivity of the Mittelgebirge near Podsedlitz and Trziblitz in Bohemia, where it is sought as an ornamental stone. At Elie in Fife it occurs in wacke or other trap rocks (Elie rubies). It is much valued as a gem, but is seldom of sufficient size. 146. HELVINE, Werner, Hauy, Phillips ; Tetrahedral-gamet, Mohs. Tesseral, and tetrahedral ; or the combination . as j n fig. 133. Crystals imbedded or attached. Cleavage, octahedral im- Fig. 133. perfect, H. = 6 6'5 ; G. = 3-1 3 -3 (3-216, Breith.). Translucent on the edges. Lustre vitreous inclining to resinous ; colour honey-yellow, wax -yellow, siskin-green, or yellowish-brown. Highly thermo-electric. B.B.in the red. flame fuses with intumescence to a yellow obscure pearl, becoming darker in the ox. flame. With borax forms a clear glass, becoming violet-blue in the ox. flame. With carbonate of soda in excess, on char- coal, forms a hepar, on platina wire a green glass coloured by manga- nese. Soluble in hydrochloric acid, evolving sulphuretted hydrogen, and gelatinizes. Chem. com. Mn S + 3R 2 si, or according to Kammelsberg, Mn, Mn S + (Mn, Fe, Be) 2 &. Analyses. Silica. Glu- cina. Iron prot. Mang. prot. Sul- phur. Sulph. ofMang. Loss by heat. Total. 1 33-26 2 35*27 3 33-26 4 35-27 12-03ffl 8-036 12-03 9-47 5-56 7-99 5-56 7-99 31-82 29.34 44-68 42-13 5-057 5-057 14-00 14-00 1-55 1-55 97 '82 97-23 101-10 100-43 C. Gmelin, Schwarzenberg. Do. Do. No. 1 by Rammelsberg. No. 2 Do. Do. (a) With alumina ; (b) + 1-45 alumina with glucina. Nos. 3 and 4 are 1 and 2 recalculated, in accordance with the new views of the composition of glucina. Helvine occurs at Schwarzen- berg in Saxony, with garnet, quartz, fluor, zinc-blende, and copper pyrites in beds in gneiss. Also found at Hortebulle near Modum in Norway, and, it is said, near Breitenbrun in Saxony. Family.~\ IDOCRASE. 147. IDOCRASE, Hauy, Phillips ; Vesuvian, Werner ; Pyramidal garnet, Mohs. Tetragonal ; P 74 14', Mohs, (varies from 73 30' to 74 20', Kupffer nndBreitkaupt). The more common forms are ooP, ooPoo , OP, P, Poo (56 15), oo P3, with many subordinate, (fig. 134) comp.p. 22. The Fig. 134. general aspect of the crystals is columnar, (fig. 135), from predo- minance of the prisms Fig. 135. ooP and oo Poo ; more rarely tabular or pyra- midal when OP or P prevails. Also occurs in columnar or granular masses. Cleavage, pris- matic along oo Poo and ooP, but imperfect ; fracture uneven, splin- tery, or imperfect conchoidal. H = 6-5 ; G. = 3-353-45, (or even 4, Breith.). Transparent to translucent on the edges. Lustre vitreous or resinous. Various yellow, green, brown, almost black colours, rarely azure-blue or verdigris -green. Streak white. B.B. fuses easily with intumescence to a yellowish-green or brown glass. Co- lours borax from iron. Partially soluble in hydrochloric acid, after fusion wholly and gelatinizes. Chem. com. ca 3 si 2 + &i si, or like garnet, with 40.2 silica, 37-1 lime, and 22-7 alumina. Analyses. Silica. Alu- mina. Lime. Mag- nesia. Iron prot. Mang. prot. Watr. Total. 1 35-50 22-25 33-00 7"50a 0'25a 98-50 Klaproth, Vesuvius. 2 36-00 17-50 37-65 2-52 5-256 trace 6 0-36 99-28 Berzelius, Gokum. 3 35-87 17-87 34-32 2'78 6'75a 0-31 a 0-25 98-15 Murray, Do. 4 38-53 17-40 27-70 10-60 3-90 0'33a 98-46 Nordenskiold, Frugard. 5 34-85 20-71 35-61 ... 5-40 96-57 v. Kobell, Mussa Alp. 6 37-64 15-42 3824 6-42 97-72 Do M. Monzoni. 7 37-18 18-11 35-79 0-77 4-67 1 : 50 98-02 Magnus, Slatoust. 8 38-52 20-06 32-41 2-99 3-42 0-02 97-42 Do. Cziklowa, Bannut. 9 37-66 17-69 31-90 4-54 6'49 0-50 98'78 Do. Egg, Norway. 10 37-36 23-53 29 -68 5-216 3-99 99-77 Do. Vesuvius. 11 37-50 1850 3371 3-10 6-25a o'i'o 99-16 Karsten, Do. 12 39-25 18-10 33-85 2-70 4-30 075 98-95 Do. Piemont. 13 38-40 18-05 3S-72 1-50 3-10 0-65 0-90c 99-;i2 Do. Sasser-Thal. 11 3.9-70 18-95 34-88 2-90 096 2-10c 99-49 Do. Hasslau, Bohemia. 15 35-09 17-43 33-08 2 : 6b 6-37a 2-80 1-68 98-43 Thomson, Amity, N. Y. (a) Peroxide; (6) with protoxide of manganese; (c) soda- Idocrase differs from garnet chiefly in form. When fuse 1, its spe- cific gravity falls from 3'346 to 2-9292-941 (Varrentrapp), agreeing with that of melted grossular-garnet. Hence, in the state of glass, the differences of the two substances disappear. 236 EPIDOTE. [Garnet Idocrase was originally found in the ejected calcareous blocks on Vesuvius, in druses with garnet, augite, hornblende, &c. It also occurs imbedded or in druses in serpentine, marble, or chlorite-slate ; but more commonly in subordinate beds with calc-spar, garnet, epi- dote, chlorite, and other silicates. Fine varieties are found on the Wilui river in Siberia ; beautifully-coloured and transparent crystals on the Mussa-alpe in Piemont ; large crystals, with numerous faces, at Egg near Christiansand in Norway ; also at Wicklow in Ireland, and near Broadford in Skye in Scotland The variety from Gokum (Nos. 2, 3) has been named Gahnile, Lo- boite, Gokumite ; that from Finuland (No. 4), Frugardite, and that from near Eger (No. 14), Egeran, but there seems no sufficient ground for separating these from idocrase. The Cyprine, from Sou- land in Tellemark, Norway, seems also a variety. It is azure-blue or green, contains copper, and B.B. melts easily in the outer flame to a black, in the inner to a red pearl. The Xanthite of Thomson (No. 15), from a limestone bed near Amity in New York, in small, greyish- yellow, translucent, loosely-connected grains, also agrees nearly in composition with idocrase, which is found in same locality. Idocrase is used as an ornamental stone, the brown being named hyacinth, the green chrysolite, but it is not highly valued. Some furnace slags agree in many points with idocrase and the connected minerals. The following are a few analyses for comparison. 1 2 3 4 5 Silica. Alu- mina. Lime. Mag- nesia. Iron prot. Mang. prot. 0-40 0-23 2-64 2-79 2-89 Pot- ash. Sulpht. calcium Total. Percy. Do. Do. Forbes. Do. 38-05 38-76 37-63 37-91 3952 14-11 14-48 12-78 1301 15-11 3.5-70 35-68 33-46 31-43 32-52 7-61 6-84 6-64 7-24 3-49 1-27 1-18 3-91 0-93 2'02 1-85 1-11 1-92 2-60 1-06 0-82 0'98 0-68 3-65 2-15 99-81 99-26 99-66 99-56 98-76 Nos. 1-4 were from hot-blast furnaces near Dudley ; No. 5 from a cold-blast furnace near Tipton. Nos. 1-4 are described as crys- tallized in square prisms, terminated by planes perpendicular to the axis, and many with their angles truncated by planes, making equal angles with the adjacent faces, (or the tetragonal combination, ooP . OP . m Poo .) G. = 2-905 2-924. Dr Percy gives for these five the formula ^i "si + 2 (c'a, Mg, Mn, Fe ) 3 "si". 148. EPIDOTE, Hauy, Phillips ; Prism atoidal Augite-spar, Mohs. Monoclinohedric ; dimensions variable. C = 89, ooP2 63 8', Pco 64 36', Poo 63 43', P 70 9', P 70 33'. The crystals always appear horizontal-prismatic, prolonged in the direction of the ortho- diagonal, and showing a predominance of the hemidomes with the Family. ,] EPIDOTE. ZOISITE. PISTAZITE. 237 basal and orthodiagonal pinakoids. They often exhibit on the one, freely formed, end very complex combinations of hemipyramids and clinodomes. Common form, fig. 136, where ooPoo (M) . Poo (T) . Fig. 136. Poo (r) P (n). The surface is often horizon- tally striated. The macles are united by a face of PGO . Crystals generally grouped in druses ; also occurs massive and columnar, granular or compact. Cleavage, orthodiagonal very perfect, hemidomatic along Pco rather perfect. Fracture conchoidal, un- even, or splintery. H. = 6 7 ; G. = 3'2 3 '5. Pellucid in all degrees. Lustre vitreous, on cleavage planes adamantine. Coloured, especially green, yellow, and grey ; rarely red and black. B.B. fusible. Strongly ignited, or after fusion all are soluble in hy- drochloric acid, and gelatinize. Chem. com. variable, but nearly da 3 si 2 + 2*R si, the lime partly replaced by magnesia or protoxide of iron or manganese ; and R in some chiefly alumina, in others iron or manganese peroxide. The following varieties have been distinguished, the zoisite being, perhaps, a separate species : (1.) Zoisite (Karsten, Werner, &c.), white, yellowish, or brown- ish-grey, chiefly in large imbedded crystals, or in foliated columnar masses. B.B. intumesces and forms a white or yellow porous mass, and on the edges fuses to a clear glass. With borax shows slight traces of iron ; with cobalt solution becomes blue. Usually regarded as a lime-epidote, but rather characterised by the very small amount of peroxide of iron replacing the alumina. Analyses. Silica. Alu- mina. Lime. Iron protox. Mang. protox. Mag- nesia. Total. 1 40-74 2 40-03 3 39-30 4 40-21 5 40-00 6 40-57 28-94 29-83 29-49 25-59 26-46 32-67 20-52 18-85 22-96 23-28 20-66 2082 5-19a 4-24 6-48 7-68 6-33 a 4-60 1-78 7-55 trace, trace. 4-75 1-36 6 1-716 3-60 c 1-226 101-92 100-50 99-59 98-47 98-55 99-88 Geffken, Faltigel, Tyrol. Do. Fichtelgebirge. Thomson, Carinthia. Do. Williamsburg, Mass. Besnard, Grossarl, Salzburg. M. Richter, Passeyer. (a) Peroxide; (&) water; (c) + 1-50 potash. Occurs imbedded in granite, diorite, or other crystalline rocks ; in subordinate veins or beds with other minerals, as in gneiss on the Sail Alpe in Carinthia ; rarely in vesicular cavities in porphyry, as in the Ural ; also found in Connecticut and other parts of North America. No. 6 was considered spodumene, but is zoisite. (2.) Pistazite, Werner ; Thallite, Beudant; pistacio-green to black- ish-green and black, also olive or siskin-green, yellow, or brown. Crystallized, or massive and imbedded in prismatic, granular, com- pact, or earthy aggregates, also in layers or crusts. B.B. fuses on 238 EPIDOTK MANGANESE-EPIDOTE. [Garnet the edges, and then swells up into a dark-brown slag, sometimes magnetic. In borax forms a glass coloured by iron. It is considered an iron-epidote, much of the alumina being replaced by the peroxide of this metal. Analyses. Silica. Alu- iniiKi. Lime. Iron perox. Mag- nesia. Total. 1 37-0 21-0 15-00 24-0 a ... 985 Vauquelin, Arendal. 2 36-14 22 '24 22-86 14-29 2.386 100-03 Geffken, Do. 3 37-98 20-78 2374 17-24 1-11 100-85 Rammelsberg, Do. 4 44-56 23-72 24-71 8-33 101-32 Do. Rothlaue, Bern, G. = 3-387- 5 40-62 29-18 22-67 6-19 073 99-81 Kiihn, Zwiesel, Bavaria. 6 40-57 7 39-85 14-27 21 -6 J 30-00 22-15 13-44 16-61 2-76 0-30 101-24 100-52 Do. Geier, Erzgebirge. Do. Dauphine. 8 38-64 9 36-68 21-98 2172 21'95 23-07 17-42 1672 0-27 0-53 100-26 98-72 Do. Penig, Saxony. Do. Arendal. 10 38-89 18-85 16-00 16-34 6-lOc 98-57 Wagner, Ural (Puschkinite). (a) + 1-5 manganese peroxide; (6) + 2-12 manganese protoxide; (c) + 0-26 manganese peroxide, 1'67 soda, and 0-46 lithia. This is the most common variety of epidote, and occurs imbedded in many crystalline rocks, as granite, diorite> euphotide, greenstone, porphyry; also in druses or vesicular cavities in trap, and in veins or beds among the crystalline schists, especially with ores of iron, copper, and other metals. The finest crystals are found in the magnetic iron at Arendal ; but others in the Ural, in Piemont (Mont Blanc), and other parts of the Alps; also in the Pyrenees, the Fichtelgebirge, the Harz, Finnland, Greenland, and North America. In Scotland it is common in Zetland in syenite ; in gneiss in Suther- land ; in trap in Mull and Skye ; in quartz in Rona ; in clay-slate in Arran ; and in porphyry in the latter island and in Glencoe. The Puschkinite (No. 10), from the Ural, of green, yellow, or red colours, G. = 8 '066, was once considered green tourmaline, but is only epidote. The Wilhamite, found in porphyry in Glencoe, in mi- nute bright red crystals, is also a variety. In transmitted light it ap- pears carmine-red in one, pale straw-yellow in another direction, which are vertical to each other, and to the lengthened prism. The Cum- mingtonite from Massachusetts is also probably this variety of epidote. (3.) Manganese-epidote (Phillips, Hauy), in which much of the alu- mina is replaced by manganese-peroxide, is of a dark violet-blue or reddish -black colour. Streak cherry-red. Forms columnar or pris- matic aggregates. H. = 6'5 ; G. = 3-404. B.B. melts easily to a black glass ; with borax shows reaction for manganese. Analyses. 1 2 3 Silica. Alu- mina. Lime. Mang. perox. Mang. protox. Iron perox. Mag- nesia. Total. 36-87 38-47 37-86 11-76 17-65 16-30 22-78 21-65 13-42 18-25 14-08 18-96 4 : 82 10-33 6-60 (7'41)a 1 : 82 99-99 10027 99-17 Geffken. Hartwall. Sobrero. (a) Protoxide of iron + 0'40 tin and copper oxide. Family.] THULITE. AXLNITE. 239 Found only at St Marcel in Piemont, along with calc-spar, quartz, and hornblende (grammatite). Sobrero found tin oxide in many other epidotes, especially from Finnland. (4.) Thulite, Brooke. Occurs massive or imbedded. Cleavable in two directions, inclined at 92 30'. G. = 3'1 3'2. Colour, rose or peach-blossom red ; translucent and vitreous. B.B. frothes, and intumesces to a white porous mass, but fuses only on the edges. Analyses. Silica. Alu- mina. Lime. Iron perox. Mang. perox. Soda. Water. Cerium oxide. Total. 1 2 42-81 46-10 31-14 1873 12-50 2-29 5-45 1-64 1-89 8-OOa 0-64 1-55 25-95 99-14 99-55 C. Gmelin. Thomson. (a) Potash. Gmelin's analysis agrees with the formula for epidote, when the iron is taken as the protoxide. Wohler has examined the genuine mineral without finding any cerium. Occurs at Souland in Tellemark, Norway. The Bucklandile of G. Rose, found in small black crystals with glassy felspar near Lake Laach, and in granite at Werchoturje, Si- beria, is described by him as a pure iron epidote. The Bucklandite of Levy from Arendal, opaque, blackish-brown, or black, and much resembling augite, seems a different mineral, but its composition is unknown. 149. AXINITE, Hatty, Phillips, $c. ; Thumerstein, Werner ; Prismatic-axinite, Mohs. Triclinohedric ; usually in very unsymmetrical crystals (figs. 137 and 138), where the inclination of u to P = 135 10', of u to / Fig. 137. Fig. 138. = 115 17', of P to r = 134 40'. The crystals are attached singly, or united in druses. Also occurs massive in laminar or broadly- radiated aggregates. Cleavage, imperfect along a plane truncating the sharp edge between P and w, and forming an angle with P of 103 5'. H. = 6-5 7 ; G. 3 3'3. Transparent, or translucent 240 CYANITE. [Garnet only on the edges. Lustre vitreous. Clove-brown, inclining to smoke-grey or plum-blue. Streak white. B.B. intumesces and fuses easily to a dark-green glass, becoming black in the ox. flame. With borax forms a glass coloured by iron, but changing to violet-blue in the outer flame, from the manganese. With fluor-spar and bisulphate of potash colours the flame green from boracic acid. Not soluble in hydrochloric acid till after ignition, when it gelatinizes. Analyses. Silica. Boracic acid. Alu- mina. Iron perox Mang. perox. M*g- nesia. Lime. Total. 1 45-00 2-00 1900 12-25 900 0-25 12-50 100-00 Wiegmann, Treseburg. 2 ;$ 43-47 43-68 5.6] 16-30 15-63 10-25 9-45 274 305 1-55 1-70 19-90 20-67& 100 : 43 Rammelsberg, Oisans (A). Do. Do. (Bl. 4 4374 6-62a 15-66 11-94 1-37 177 18 -90 100-00 Bo. Treseburg, Harz. r 4372 5-81a 16-92 10-21 1-16 2-21 19-97 100-00 Do. Miask. (a) With alkali and loss ; (&} + 0-64 potash. The composition, as these analyses show, is very complex. L. Gmelin assigns 4 R & + 2 R s'i 2 + ca 2 B', or a double salt of silica, combined with borate of lime. Rammelsberg, again, considers the boracic acid as isomorphous with silica, and gives (ca M g ) 3 (si "B ) 2 + 2 (ALFe, Mn) (*sY, B')- In another experiment Rammelsberg found the boracic acid 3 '40 per cent., and thinks the mean, or 4 - 5, nearest the true amount. Haidinger describes this mineral as showing distinct trichroism, being cinnamon-brown in one direction, dark violet-blue in a second, and pale olive-green in a third. Riess and G. Rose found in it two pyroelectric axes, which do not pass through the centre, nor corre- spond with those of the crystal. Axinite is not very abundant, and occurs chiefly in fissures, veins, or subordinate beds, especially in granite, hornstone, diorite, gneiss, and in mica, hornblende, and clay- slate, associated with quartz, felspar, epidote, chlorite, asbestus, &c. It is found rarely in mineral veins, as those of silver at Kongsberg in Norway ; in beds with magnetic iron (Arendal, and Nordmark in Sweden), zinc-blende, copper pyrites, and other ores. The finest crystals are from Bourg d'Oisans in Dauphine, and the Botallack mine in Cornwall. At the latter it also appears mas- sive and compact, forming a peculiar rock with garnet and tourmaline. This variety, according to Turner (not confirmed by Rammelsberg), does not exhibit the reaction for boracic acid. The Pyrenees, Savoy, Tyrol, Thum in Saxony, the Ural, and Maine, North America, are other localities. 150. CYANITE, Kyanite, Phillips, fyc. / Zianite, Werner ; Disthene, Hauy, 8fc. ; Prismatic Disthene-spar, Mohs. Monoclinohedric ; C. = 106 15'. Generally in broad prismatic Family.] SILLIMANITE. 241 crystals much lengthened along the orthodiagonal, and formed chiefly by ooPoo, OP, and Poo (OP : POD = 122 20'), the prisms often Fig. 139. bounded by ( ooPoc ) (fig. 139). Macles are common, united by ooPoo. The crystals are imbedded singly. Also found in even, curved, radiated or confused co- lumnar aggregates. Cleavage, orthodiagonal very per- fect, basal less perfect. Brittle ; H. = 5 7 ; G. = 3'5 3*7. Transparent to translucent only on the edges. Lustre vitreous, on ooPoo pearly. Colourless, or coloured bluish- white, beiiin and azure-blue, also grey, green, yellow, or red. Be- comes electric by friction, and sometimes positive on the one, nega- tive on the other side. Not affected by acids. B.B. infusible alone. With salt of phosphorus leaves silica ; with cobalt solution becomes dark-blue. Chem. com. A! si , with 37*6 silica, and 62*4 alumina. Analyses. Silica. Alu- mina. Iron perox. Total. J 430 55-5 0-5a 98-5 Klaproth, St Gotthardt. 9, 34-33 64-89 99-22 Arfvedson, Do. 3 36-90 <>470 M 101-6 Do. Do. 4 36-4 63-8 100-2 Do. Roraas. fi 42-0 57-5 99-5 Vanuxem, St Gotthardt. 6 42-56 57-00 99-56 Do. Chesterfield Massachusetts. 7 36-67 63-11 1-19 100-97 Resales, St Gotthardt. 8 9 37-36 34-40 62-09 61-86 0-71 0-526 100-16 96-97 Erdmann, Tyrol 'G. = 3'661.) Do. Roraas (G. = 3'124.) 10 37-30 62-60 1-08 100-98 Jacobson, Greiner, Tyrol (G. = 3-678.) (a) + trace of potash ; (b) + 0-19 copper protoxide. Cyanite occurs chiefly in mica and talc slates, but also in granite, gneiss, dolomite, and crystalline limestone. The finest crystals are found near St Gotthardt, and at the Greiner and Pfitsch in Tyrol. Some white or red varieties from the latter are named Rhcetizite. Large crystals also occur at Pontivy in France, in Bohemia, and in South and North America. Fine blue lamellated varieties occur at Botriphny in Banffshire, and it has also been found in Zetland. Tran- sparent blue cyanite is often polished and substituted for sapphire, but is easily known from its inferior hardness. 151. SILLIMANITE, Bowen. Triclinohedric (according to Dana) with o>P' : cx/P = 98, P' : ooP' = 105. Crystals long and slender ; also fibrous, parallel, or slightly divergent. Cleavage, macrodiagonal highly perfect ; H. = 7 7'5 ; G. = 3'2 3'26. Translucent ; vitreous, inclining to pearly ; greyish- brown, clove, or hair-brown. B.B. infusible alone ; not affected by acids. Analyses, next page. 242 BAMLTTE ANDALUSITE. [Garnet Silica. Alu- I Iron mina. iperox. Mag- nesia. Watr. Total. I 42-67 54-11 200 0'51 99 '29 Bowen. 2 38 -<>7 35-11 722 18-51a 99-51 Muir. 8 36-75 581)4 0-99 *.. 9668 Connel. 4 3770 62-75 2-29 1(12-74 Norton. 5 37-36 58-62 2-17 0-40 3 98-98 Staaf. 6 45-65 4950 4-106 99-25 Thomson (1845). 7 42'60 54-90 MOc 0-40 9931 Hayes. 8 47-44 52-54 99-98 Komonen (Xenolite). 9 40-79 53-06 ... 0-88 4-63 99-36 Hess (Worthite), m. of 2. (a; Zirconia; (b) protoxide; (c) with protoxide of manganese, +0-31 lime. The zirconia found by Muir has not been again observed. The other analyses also differ considerably. Nos. 1-7 give nearly Jii 4 & 9 ; No. 6 A! 2 si , agreeing with Xenolite, No. 8 ; and No. 5 1 si i or tne same with cyanite ; whilst the loss in No. 3 and the excess in No. 4, render them uncertain. It is thus doubtful whether this mineral is distinct from cyanite, to which its angles approach very near. It is found in quarz in gneiss at Chester, and near Norwich in Connecticut, and in long white or wine-yellow prisms at Tvedestrand in Norway ; also with magnetic iron near Yorktown in New York. The Xenolite, found in loose fragments at Peterhoif in Finnlaud, and the Worthite, opaque, pearly, and white, from loose blocks near St Petersburg, seem nearly related to this mineral, or cyanite. 152. BAMLITE, Erdmann. Monoclinohedric ? in oblique four-sided prisms, usually strongly striated ; also massive and radiated fibrous. Fracture uneven and splintery ; H. = 6 7 ; G. = 2'98. Translucent, colour greyish- white. B.B. infusible. Becomes blue with cobalt solution. Chem. com. Ai 4 si 9 , with 57'6 silica, and 42'4 alumina. Erdmann found 56*90 silica, 40'73 alumina, T04 iron peroxide, 1*04 lime, and trace of fluorine (= 99*71.) It occurs in quartz masses in gneiss at Brakka in Bamle near Brevig in Norway. 153. ANDALUSITE, Lametherie, Werner, Hauy, Phillips, fyc. ; Prismatic Andalusite, Mohs. Rhombic ; ooP 90 50', Poo 109 4' ; usual combinations, ooP . Fig. 140. OP, or this with Poo (fig. 140). The crystals are prismatic, often large, and attached or imbedded. Also forms diverging, columnar, or granular aggregates. Cleavage, prismatic along ooP, rather indistinct ; traces along ooPco , ooPoo and Poo . Fracture uneven, splintery ; H. = 7 _ 7.5. Q.. _ 3-1 _ 3-3. Translucent or only on the edges ; rarely transparent, and then shows distinct tri- Family.'] ANDALUSITE. 243 chroism. Lustre vitreous. Always coloured, grey to green, flesh or peach-blossom-red, violet-blue or reddish-brown. B.B. infusible alone, with borax forms with difficulty a clear glass. In powder becomes blue with cobalt solution. Not affected by acids. Chem. com. Ai 8 si 9 , with 40'4 silica, and 59 '6 alumina. Analyses. Silica. Alu- mina. Iron perox. Mang. perox. Lime. Mag. nesia. Total. 1 38 52 2 ... ...a 100 Vauquelin, Spain. 2 36-5 60-5 4-0 ... 101-0 Bucholz, Herzogau. 3 40-17 58-62 : 51 0-28 9958 Bunsen, Lisens. 4 35-30 60-20 1-326 l : 00c 99-85 Thomson, Tyrol. 5 37-65 59-87 1-87 : 58 0-38 100-35 Svanberg, Fahlun. 6 37'51 60-01 1-49 0-48 0-46 99-95 Kersten, Triebischthal (G. = 3'152). 7 39-99 8 39-09 58-60 58-56 0-72 0-83 0-53 : 21 '".d 100 14 99-38 Erdmann, Lisens. Bunsen, Lancaster Mass. 9 46-0 50-0 2 : 5 ... ...e 100-00 Brandes, Faltigel, Tyrol. 10 46-40 52-92 99-32 Thomson, Chester, Pens. 11 40-08 58-88 074 ... 9967 Erdmann, Do. (G. = 3 239). 12 38-00 58-25 0-75 ... 97-00 Chevenix, Camatic. fa) +8 potash; (b) protoxide; (c) +2-03 water; (d) + 0-99 volatile ; (e) + 1-5 potash. Nos. 2, 4, 5, 6 nearly agree in composition with cyanite, and are perhaps pseudomorphs of that mineral. In Nos. 9, 10 Rammelsberg supposes the silica to contain some undecomposed mineral. Andalusite occurs chiefly imbedded in mica slate, or in druses in other crystalline rocks. It was first found in Andalusia, but since in fine varieties at Lisens in the Tyrol, Penig in Saxony, Westford Mass., and Litchfield Connecticut. It also occurs in gneiss at Botriphny in Banffshire, and in mica slate at Killiney Bay in Wicklow. The finely fibrous varieties (Nos. 9-12) have been named Bucholzito or fibrolite, but are identical in composition. Chiastolite (Phillips ; Hohlspath, Werner) No. 8, 1 has been considered a distinct species. It is of a dirty or pale-grey, yellow, or red colour, with dull vitreous lustre. It occurs imbedded in clayslate, especially near granite, and often appears like four crystals separated by a black Fig. 1 41. cross of the dark slate (fig. 141). Mohs endeavours to ex- plain this mosaic formation, as it was named by Hauy, from a made, but there are still some difficulties attached to this theory. Thus in some the black colour is destroyed by heat, in others it is not continuous, and in others again pervades almost the entire mass. In some, too, the light part seems composed of irregular fragments. It is found in the Fich- telgebirge, in Brittany, the Pyrenees, in the Sierra Morena, and at St Jago di Compostello in Spain, where it is cut into rosaries or amulets, and sold to the pilgrims. It is abundant at Lancaster and Sterling in Massachusetts. Also common at Wolfscrag near Keswick, and on Skiddaw in Cumberland ; near Balahulish in Argyleshire ; and in Wicklow in Ireland. 244 STAUKOLITE. {Garnet 154. STAUKOLITE, Karsten, Phillips ; Stanrotide, Hauy ; Grenatite, Jameson ; Prismatoidal-garaet, Mohs. Rhombic; ooP 29 20', P~oo 69 16', common combinations ooPCflf). ooPoo (o) . OP (p) and ccPoo . ooP . Poo ; the crys- tals short and thick, or long and broad columnar ; surface often rough or corroded. Twin crystals very common, with chief axes intersecting, either almost at right angles, (fig. 142), or at nearly 60 (fig. 143). Cleavage, brachydiagonal perfect, traces along ooP. Fracture conchoidal, or uneven and splintery. H. = 7 7'5 ; G. = 3'5 3 '8. Translucent or opaque. Lustre vitreous, inclining to resinous. Colour reddish to blackish-brown; streak white. B.B. infusible Fig. 142. Fig. 143. M\ ?-' p 1-^1 f\ J M\ alone ; in borax with difficulty to a dark green glass ; in soda with effervescence to a yellow slag. Not affected by hydrochloric acid, and only partially by sulphuric. Analyses. Silica. Alu- mina. Iron per ox Mag- nesia. Man- gamse. Total. 1 30-31 2 30-91 3 29-72 4 29-13 5 28-47 6 33-22 7 39-77 8 38-51 46-80 48-68 54-72 52-01 53-34 4758 44-55 46-70 18-08 15-37 15-69 17-58 17-41 16-58 15-43 14-83 2-16 1-33 1-85 1-28 072 1-83 0-16 2-46 ...a 1-196 : 31c : 13(J 97-48 97-48 101-98 100-00 100-25 99-20 100-04 102-49 Jacobson, St Gotthardt (G. 3737 solid to Do. Do. [3- 744 in powder.) Do. Do. Do. Do. Marignac, Do. Jacobson, Airola, Do. (G. = 3-66 373.) Do. Brittany, (G. =3-527 3-529.) Do. Polewskoi, Ural, (G. = 3-547 3-588.) (a) +0-13 lime; (b) protoxide; (c) peroxide; (d) proto-peroxide. Nos. 6, 7, 8 are means of two trials agreeing closely. These ana- lyses do not lead to any common formula, and the older ones are still more discordant. The St Gotthardt variety gives nearly 'R 3 si 2 ; that from Airolo, R si, or the formula of cyanite ; and those from Family.] DIASPORE. 245 Brittany and the Ural, 5 si 6 . But, as Kammelsberg remarks, this difference of composition in bodies with the same form of crys- tallization, is difficult to be received ; and hence, he suggests, that the silica is isomorphous with the bases "jj (= A! an d re.) Per- haps this is also the case in cyanite and andalusite, which may ex- plain the variations in their composition. The specific gravity de- creases with the amount of silica. It occurs imbedded in mica, talc, and clay slate, more rarely in gneiss. Fine crystals are found at St Gotthardt and the Greiner in Tyrol along with cyanite. It is sometimes curiously combined with the latter, the two minerals presenting themselves in continuous position, as if forming one and the same crystal. It is also common in many parts of the Pyrenees, in Spain, Bohemia, the Ural, and in North America. In Scotland it occurs in Aberdeenshire and the Hebrides. 155. DIASPORE, Hauy, Werner^ Phillips ; Eutomous Disthene-spar, Mohs. Rhombic ; broad indistinct prisms, formed chiefly by ooPoo , along with P3, and bounded on the ends by the curved faces of the fundamental form P (fig. 144). Usually massive in thin Fig. 144. foliated or broad radiated aggregates. Cleavage bra- chydiagonal highly perfect ; very brittle ; H. = 6 ; G. = 3 '3 3*4. Transparent or translucent j lustre pearly onooPoo ; colourless, but generally yellowish or greenish- white, also violet-blue, and often appears yellowish- brown from hydrated peroxide of iron ; insoluble in acids. B.B. decrepitates into small white scales, but is infusible alone ; fusible in borax, and with solution of cobalt becomes blue. The diaspore from Kosoibrod does not decrepitate, but yields much water, and becomes brown ; and after ignition is soluble in warm sulphuric acid. Chem. com. A! H = 85 alumina and 15 water. Alu- Watr. Iron Silica. Lime. Total. 1 85-52 14-48 100-00 Hess, Miask (m. of 2). 2 3 4 78-93 74-66 79-91 15-13 14-58 14-90 0-52 4-51 1-39 2-90 1-98 1-64 ...a 9795 98-29 100-61 Dufre'noy, Broddbo. Do. Katharinenburg. Damour, Siberia. 5 85-13 15-00 ... 100-13 Lowe, Schemnitz (G. =3.303). (a) + 5-80 remainder. Rare ; but found in veins with brown iron ore in chlorite slate in the marble quarries near Kosoibrod and Gornoschit in the Ural ; and in veins between dolomite and limestone near porphyry at Schemnitz; 246 H YDRARGILLITE PERICLASE . [Garnet also at Broddbo near Fahlun. The specimens from Schemnitz show a beautiful trichroisin, especially in polarized light, appearing violet- blue in one direction, reddish plum-blue in another, and pale aspara- gus-green in a third. 156. HYDRARGILLITE, G. Rose. Hexagonal, in very small crystals of the form of OP . ooP . o>P2, or in granular scaly masses. Cleavage, basal very perfect ; H = 2'5 3 ; G. = 2-3 2-39. Translucent ; lustre pearly on OP, otherwise vitreous ; colourless or reddish-white ; slowly soluble in warm acids ; in closed tube yields water. B.B. exfoliates, and gives out a strong light, but is infusible. Becomes blue with cobalt solution. Found in the talc slates of Schischimskaja Gora near Slatoust in the Ural. GIBBSITE, Torrey, Phillips, Mohs ; Gipsite, Beudant. Stalacty- tic, or botryoidal masses, with thin, radiated, prismatic texture, H. = 3 3-5 ; G. = 2-4. Slightly translucent ; dull ; dirty-greenish or greyish-white ; in closed tube yields much water. B.B. infusible, but becomes fine blue with solution of cobalt ; soluble in acids. Found in a vein of brown iron ore at Richmond, Massachusets. Analyses. 1 2 3 4 5 Alu- mina. Watr. Silica. Iron Phosphoric perox.) acid. Total. 64-8 54-91 64-03 26-66 65-6 34-7 33-60 34-54 3572 34-4 873 3-93 1-43 37-62 99-5 101-16 100 100 100 Torrey, Richmond. Thomson, Do. Hermann, Ural (G. = 2-387). Do. Richmond, v. Kobell, Villa Ricca. Hermann's analysis of the hydrargillite, No. 3, agrees, except in the small amount of phosphoric acid, with Torrey 's of the gibbsite, and gives the formula AI H 3 , with 65'5 alumina, and 34'5 water. His analysis of the latter, No. 4, gives a very different result, or AI '* + 8 H. If this is the true gibbsite, it should retain that name, and have a place in the system near wavellite. No. 5, the so-called wavellite from Villa Ricca, Brazil, is a true hydrargillite. 157. PERICLASE ; PERIKLAS, Scacchi. Tesseral, as yet only in octahedrons ; cleavage, hexahedral perfect ; H. = 6 ; G. = 3 '75. Transparent ; lustre vitreous ; colour dark- green. B.B. infusible ; powder soluble in acids. Chem. com. mag- nesia, partly replaced by protoxide of iron. Analyses, next page. Family.'} GLAUCOPHANE WICUTYNE VIOLAN. 247 1 2 3 Mag- nesia. Iron prot. Inso- luble. Total. 89-04 92-57 91-18 8-56 6-22 5-67 o'-86 2-10 97-60 99-65 98-85 Scacchi. Damour. Do. In the first analysis the loss was probably magnesia. Damour deter- mined the iron to be the protoxide. It is found at Monte Somma near Naples. 158. GLAUCOPHANE, Hausmann. Rhombic or monoclinohedric, but only found in indistinct, thin prismatic crystals, or massive and granular. Cleavage, prismatic along ooP distinct. Fracture conchoidal, H. =5-5; G. = 3'108. Translucent or opaque ; vitreous or pearly on the cleavage planes ; and greyish, indigo or lavender-blue, or bluish-black. Slightly mag- netic. B.B. becomes yellowish-brown, and fuses readily to an olive- green glass. Partly soluble in acids. Chem. com. 2 jii si 3 + 9 R si , or by Schnedermann's analysis, 56'49 silica, 12*23 alumina, 10'91 iron protoxide, 7*97 magnesia, 2-25 lime, and 9'28 soda, with traces of potash (= 99'63). It occurs in mica-slate in the Island of Syra, with garnet, hornblende, and chlorite. The characters of this species are still uncertain, and it is placed here only provisionally. The following minerals, if true species, are nearly connected with it. WICHTYNE, Laurent. Massive, with traces of cleavage probably along a rhombic prism ; G. = 3 '03 H. scratches glass. Lustre dull, colour black. B.B. fuses to a black enamel. Not affected by acids. Chem. com. i si 8 + 3 k si, or by Laurent's analysis, 56*3 silica, 13 '3 alumina, 13 '0 iron protoxide, 4'0 iron peroxide, 3*0 mag- nesia, 6 - lime, and 3-5 soda ( 99-1). Found at Wichtis in Finn- land, and hence Hausmann changes the name to Wichtisite. VIOLAN, Breitfiaupt. Rhombic ? but only massive with cleavage along a slightly oblique rhombic prism ; H. = 5 6 ; G. = 3-233. Opaque, resinous, dark-violet-blue, with bluish-white streak. B.B. fuses easily to a clear glass. With borax in the ox. flame forms a brownish-yellow glass, violet-red when cold ; in red. flame a yellow glass, colourless when cold. Chem. com. according to Plattner, essentially silica, alumina, magnesia, lime, natron, iron, and manga- nese. Found with the manganese-epidote at St Marcel in Piemont. BOLTONITE, Shepard; Silicate of magnesia, Thomson. Massive and coarse granular. Cleavage in one direction perfect, in two others oblique, imperfect ; H. = 5 ; G. = 2 -8 2-9. Translucent, yellow- ish-grey to wax-yellow. B.B. infusible. Chem. com. perhaps (ME, Fe) (SS, i)> or by Thomson's analysis, 56'64 silica, 36'52 mag- 248 ZIRCON. \_Gems nesia, 6'07 alumina, and 2-46 iron protoxide (= KDl'69). Found in a white limestone at Bolton, and in other places in Massachusetts and Connecticut. XI FAMILY GEMS. 159. ZIRCON, Hauy, Phillips; ZIRKON, Werner; Pyramidal Zircon, Mohs. Tetragonal ; P 84 20', most frequent combinations ooP . P, often with 3P3 ; also ooPoo . P (like fig. 123, p. 168), and P . ooPoo . Fig. 145. 2P . 3P . ooP. In fig. 145 still more forms are seen, or ooPcc (s) . ooP (/) . P (P) . 3P3 (*) . P 00 (0 . 4P4 (y) . 5P5 (z). Oc- curs in imbedded crystals, chiefly prismatic or pyramidal ; and in rounded grains. Cleav- age pyramidal along P, and prismatic along oo P, both rather imperfect. Fracture con- choidal or uneven ; H. = 7-5 ; G. = 4 4-7. Transparent to opaque ; lustre vitreous, often adamantine, Colourless, rarely white, gene- rally grey, yellow, green, or frequently red and brown. B.B. loses its colour, but is in- fusible alone or with salt of phosphorus, slowly in borax to a clear glass. Not affected by any acid, not even the hydrofluoric, except concentrated sulphuric acid, which partially decomposes it after long digestion. Chem. com. zr 2 si, or 66 '23 zirconia, and 33*77 silica. Analyses. Silica. Zir- conia. Iron perox. Total. 1 26-5 69-0 0-5 96-0 Klaproth, Zircon, from Ceylon. 2 3 25-0 32-5 70-0 64-5 0-5 1-5 95-5 98'5 Do. Hyacinth, Do. Do. Zircon, Northern Circars. 4 33 65 1 99 Do. Do. Fredriksvarn, Norway. fi 34-00 64-00 0-25 98-25 John, Do. Do. 6 7 32-6 33-48 f4-5 67-16 2-0 99-1 100-64 Vauquelin, Hyacinth, Ceylon. Berzelius, Do. Expailly, Auvergne. 8 32-08 67-07 99-15 Vaxuxem, Zircon, North Carolina. 9 35-26 63-33 0-79a 9974 Gibbs, Litchfield Maine, (G. = 4'7). (a) + 0-36 undecomposed mineral. In 1789 Klaproth discovered the earth named zirconia in this mi- neral, and showed its identity with the Hyacinth. Thomson states that it contains alumina, and Svanberg finds that the zirconia is mixed in various proportions with Noria, which may explain the difference Family.'] MALAKON SPINEL* 249 in hardness and specific gravity in different specimens. The Stock- holm variety has G. = 4'03 and lower hardness than others. The Norwegian zircon seems to contain most noria. Zircon is most abundant in the syenite of southern Norway, and in very fine crystals in the miascite of the Bmen mountains in the Ural. It is also found in the iron mines at Arendal ; in granite and gneiss near Stockholm in Sweden, in Carinthia at the Sau Alpe, in Tyrol at Pfitsch, and at Baltimore in New Jersey, and other parts of North America. In Scotland at Scalpay in Harris, and in the granite of Criffel in Kirkcudbrightshire. It occurs in basalt at Unkel, and in the Siebengebirge on the Rhine, and near Expailly in France ; in amygdaloid near Vicenza ; in ejected blocks at Lake Laach and Vesu- vius. It is found in grains or loose crystals in Ceylon, and in the gold sands of Ohlapian in Siebenburg, and of the Ural. The colourless varieties are often sold for diamonds. The more brilliantly coloured are named hyacinth, but are rarely of large size, and many hyacinths are garnets known by their inferior gravity. The hyacinthus of the ancients was a different stone, and the lyncurius seems rather to have been the zircon. 160. MALAKON, Scheerer. Tetragonal ; P 82 ; occurs in small imbedded crystals of the com- bination ooPoo . P . oo P, like zircon. Cleavage unknown ; fracture .conchoidal; H. = 6 ; G. = 3*9 3'913. Opaque, or in splinters yellowish translucent ; lustre resinous on fracture, vitreous on the crystal faces. Colour internally bluish-white, but on the surface mostly coloured brownish, reddish, yellowish, or blackish. B.B. is infusible, but ignites slightly on heating, loses 3*027 per cent, water, and the specific gravity increases from 3'9 to 4*2. In fine powder decomposed by digestion in sulphuric acid before ignition. In other respects acts like zircon. Scheerer found in his analysis 31-31 silica, 63-40 zirconia, 0'41 iron protoxide, 0'34 yttria, 0'39 lime, O'll mag- nesia, 3*03 water (= 98'99). Its composition is thus that of zircon with 3 per cent, water ; the latter perhaps not essential. It seems a peculiar modification of zirconia, which changes by ignition into the usual variety. It is found at Hittero in Norway. 161. SPINEL, Werner, Hauy, Phillips; Dodecahedral Corundum, Mohs. Tesseral ; common forms O, ooO, and 303 ; the octahedron often alone, and generally predominating. Macles united by a face of O, and individually much shortened (fig. 146). Occurs in single im- 250 SPINEL. [Gems Fig. 146. bedded or attached crystals, rarely in druses ; also in loose grains or fragments. Cleavage, octahedral imperfect ; fracture conchoidal. H. = 8 ; G. = 3-4 3 -8. Transparent to opaque ; lustre vitreous. Colourless ; but generally coloured red- dish-white, rose, carmine, crimson, blood, or hyacinth red ; bluish-white, smalt, in- digo, or violet-blue ; bluish-black, grass- green, and greenish-black. Streak white. B.B. infusible and unchanged, except the red variety from Ceylon, which, when cooling, becomes green, then colourless, and again red. With borax or salt of phosphorus yields a clear bead, slightly coloured by iron or chrome. Chem. com. M g Xi = 72 alumina, and 28 magnesia ; but part of the mag- nesia replaced by iron protoxide, part of the alumina by iron perox- ide, and the red varieties often contain chrome. Analyses. Silica. Alu- mina. Mag- nceia. Iron protox. Chrome. Total 1 5-48 72-25 14-63 4-26 96-62 Berzelius (1817), Aker, blue S. 2 3 2-25 68-94 86-00 25-72 850 3-49 5-2/5 a 100-47 99-75 Abich (1830), Do. Vauquelin, Ceylon, red S. 4 2-02 6901 2621 071 1-lOb 99-05 Abich, Do. do. 5 5-62 73-31 13-63 trace ... c 99-98 Thomson, Franklin, N. J. . green S. 6 7 6-60 5-09 6179 55-17 17-87 17-65 10-56 18-33 ..d .. e 99-60 98-95 Do. Amity, N. Y., do. Scheerer, Arendal. 8 3-15 57-20 18-24 20-51 99-10 C. Gmelin, Ceylon (Ceylonite). 9 2-50 65-27 17-58 13-97 99-32 Abich, Ural. 10 1-23 66'89 23-61 8-07 9980 Do. Monzoni, Fassathal. 11 2-38 67-46 25-94 5-06 100-84 Do. Vesuvius. 12 179 59-66 17-70 19-29 99-17 Do. Iserweise. 13 1-83 62-84 24-87 3-87 './ 99-56 Do. Monte Somma. 14 61-17 2-92 35-67 99-76 Quadrat, Bonsperg, Bohemia. (a) Chromic acid ; (6) chrome oxide ; (c) + 7'42 lime ; (d) + 2'80 lime and 0-98 water ; (e) + 2-71 protoxide of manganese; (/) + 6-15 peroxide of iron. The older analyses are imperfect, partly from the hardness of the mineral, partly from its resistance to reagents. Abich's analyses were performed by fusing the finely-pounded mineral with carbonate of barytes. The Spinel or Spinel-ruby, comprising the red and violet varieties, Nos. 1-6, occurs chiefly in Ceylon, Ava, and other parts of the East, in loose grains in the rivers. Its original locality, said to be in gra- nite, gneiss, or dolomite, is unknown. A blue variety is found in marble at Aker iron works in Sbdermanland in Sweden. This has been named Saphirine (Giesecke, Phillips, Mohs), along with a similar mineral from Fiskenaes in Greenland, in which Stromeyer found 14 per cent, silica. The dark varieties, Eos. 7-13, with G. above 3 '65, Family.'] AUTOMALITE. 251 are named Pleonasle (Hauy, Phillips), and are found either loose near Candy in Ceylon ( Candite, or Zeilanite, Werner) ; or in perfect cry- stals, in dolomite on Monte Somma, at Monzoni, in calc-spar in the iron ore at Arendal, in several places in Germany, in the Ural near Kyschtimsk, and at Warwick in New York. When large and highly-coloured, the spinel is prized as an ornamental stone. The rose-red are named Balas ruby ; the yellow or orange- red, Rubicelle ; and the violet, Almandine-ruby. No. 14 is the Hercinite of Zippe, a black spinel found in Bohemia in alluvium, G. = 3-91 3-95. On ignition the leek-green powder becomes brick-red, and the weight increases 3-2 per cent, from the higher oxidation of the iron. The Chlorospinel (G. Rose), from the talc-slate of Slatoust in the Ural, is a grass-green variety, with a yellowish -white streak. H. = 8 ; G. = 3'591 3'594. It becomes brownish-green when heated, and with borax fuses easily to a light-green glass, colourless when cold. The crystals are 1 3 lines in diameter, and are associ- ated with magnetic iron ore and yellow garnet. Analyses. Alumina. Iron perox. Magnesia. Lime. Copper protox. Total. 2 64-13 57-34 8 7l> 14-77 26-77 27-49 0-27 0-27 0-62 100-14 100-22 H. Rose. Do. 162. AUTOMALITE, Ekebcrg, Werner, Phillips; Gahnite, Hausmann, Beudant; Octahedral corundum, Mohs. Tesseral ; O sometimes simple, sometimes as a made. Cleavage, octahedral perfect. Brittle, with conchoidal or splintery fracture. H. = 8 ; G. = 4-1 4-3 (4-3 4 -589, G. Rose). Opaque or trans- lucent on the edges. Lustre vitreous, inclining to resinous. Dark leek-green to blackish-green and blue. Streak grey. B.B. unchanged alone, and nearly so with borax and salt of phosphorus ; in fine powder with soda in the red. flame leaves traces of zinc oxide on the charcoal. Not affected by acids or alkalis. Chem. com. zn A!, with 56 alumina, and 44 zinc oxide, but the latter partly replaced by pro- toxide of iron or magnesia. H. Rose thinks the silica in it and other spinel minerals accidental. Analyses. 1 2 3 Alu- mina. Zinc oxide. Iron protox. Mag- nesia. Silica. Manga- L tl nese. j 101 60-24 55-14 67-09 24-25 30-02 34-80 9-25 a 5-85 4-55 5 : 25 2-22 4-75 3-84 1-22 trace b trace traces c 98-25 100-10 99-38 Ekeberg, Fahlun. Abich, Do. Do. North America, (a) Peroxide ; (1) with lime ; (c) with cadmium. 252 CORUNDUM. [Gems Found crystallized in talc-slate along with zinc-blende and galena near Fahlun, also at Broddbo. Compact near Sather and Garpen- berg in Sweden. Also at Haddam in Connecticut, with garnet and chrysoberyl ; and at Franklin in New Jersey. A. black spinel or pleonaste, from Bodenmais in Bavaria, is dis- tinguished by Breithaupt. It has G. = 4-89 ; and, according to Plattner, B.B. shows with fluxes reaction for iron, with cobalt solu- tion for alumina, and with soda and borax a deposit of zinc oxide. 163. CORUNDUM, Phillips, -c. ; Corindon, Telesie, Hauy ; Korund, Demantspath, Werner; Khombohedral Corundum, Mohs. Rhombohedric, isomorphous with peroxide of iron and chrome ; R 86 4'. The forms that generally predominate are ooP2 (s), OR (0), R (P) ; and several hexagonal pyramids of the second kind, especially f P2, f P2, and 4P2. The general character of the combi- nations is pyramidal (fig. 147), prismatic (fig. 148), or rhombohedral. 147. Fig. 148. It occurs in crystals imbedded or loose ; also in coarse or fine granular masses. Macles common, united by a face of R, and often repeated in a lamellar form. Cleavage, rhombohedral along R, or basal in very various degrees of perfection. Fracture conchoidal, to uneven and splintery ; extremely tough, and difficultly frangible. H. = 9 ; G- =3-9 4. Transparent or translucent. Lustre vitreous, some- times pearly on OR. Colourless and" white, but generally blue, red, yellow, brown, or grey. B.B. unchanged alone ; the fine powder be- comes blue with cobalt solution ; with borax and salt of phosphorus fuses difficultly to a clear glass. Chem. com. alumina with a minute proportion of peroxide of iron or other colouring matter. H. Rose Family.'] CORUNDUM. 253 has shown that the silica found by Klaproth and others was derived from the mortar. Three varieties are distinguished in this mineral : (1.) Sapphire, highly transparent varieties, with very imperfect cleavage and con- choidal fracture ; those of fine red colours being often named oriental rubies and the blue salamstein. (2.) Corundum, in rough crystals or masses with distinct cleavage, less transparent and duller colours. Some, named asteria or star sapphire, when cut en cabochon perpendi- cular to the axis of the prism show a bright opalescent star of six rays corresponding to the other axes. The adamantine spar is a variety with very distinct cleavage, hair-brown colour, and adamantine lustre. (8.) Emery (Schmirgel, Werner), is the compact, dimly translucent varieties of grey or indigo-blue colours. The finest sapphires come from the East, especially Ceylon, where it occurs loose or imbedded in gneiss ; Ava and Pegu. Smaller crystals have been found loose near Bilin and Merowitz in Bohemia, near Hohenstein in Saxony, and in the sand of the Expailly river near Le Puy in Auvergne. It occurs imbedded in granite in the Chamouni valley, and near Newton in New Jersey ; in basalt on the Rhine ; and in the millstone lava of Niedermenning near Lake Laach. The oriental ruby when perfect is valued at about half the price of the diamond, but does not occur of such size ; though Allan mentions one three inches long ; and another valued at L.3000. The corun- dum occurs in granite rocks in the Carnatic, Malabar, Ava, and near Canton in China, of a red or blue colour in the dolomite of Campo Longo near St Gotthardt, and in large crystals in granite in Piemont. The adamantine spar is found at Gellivara in Lapland imbedded in magnetic iron ; also in the Ural, in Malabar, and in several parts of North America. Emery is chiefly brought from Naxos and other of the Greek islands, but also occurs in large boulders near Smyrna, in talc slate on the Ochsenkopf near Schwarzenberg in Saxony ; in Spain and in Greenland. Besides its value as an ornamental stone, the sapphire has been used for lenses for microscopes, for jewelling watches, and when bored for drawing fine gold and silver wire. Emery is employed as a po- lishing material, the blue coloured being the best, that from Spain the most common, but frequently mixed with magnetic iron and quartz. Some varieties contain none of the real emery, but are mere mixtures of quartz, garnet, iron oxide, and similar substances. The sapphirus of the Greeks and Romans seems to have been the Lapis-lazuli, and not this stone. The Astrios of Pliny was, however, the star sapphire ; and the 2/Ai)g/g probably the emery. 254 CHRYSOBERYL. {Gems 164. CHRYSOBERYL, Phillips, Hausmann ; Cymophane, Hauy ; Prismatic Corundum, Mohs, Jameson. Rhombic ; P with polar edges 86 16' and 139 53' ; 00 119 46', coP3 109 20' ; common combinations ooPoo (M ). ooPco ( T). Poo (t), or this with cP3 (s), and also with P (o), fig. 149, and other Fig. 149. forms. The crystals appear short and broadly columnar, or thick tabular with vertical striae. Macles veiy common, united by a face of Pco * and often repeated. Crystals imbedded or loose ; also in rounded fragments and grains. Cleavage, brachydiagonal imperfect ; macrodiagonal more indistinct. Fracture conchoidal. H. = 8'5 ; G. = 3-68 3'8. Transparent or translucent. Lustre vitreous, sometimes resinous. Colour greenish- white, leek-green, olive-green, and green- ish-grey ; sometimes with a bluish opalescence, or beautiful dichroism. B.B. infusible alone; with borax slowly and with difficulty to a clear glass. Not affected by acids. Chem. com. 6 Ai or 80*25 alumina and 19*75 glucina. Alu- mina. Glu- cina. Silica. Iron prot. Titan, acid. Loss by heat. Total. 1 2 3 4 5 6 68-67 73-60 76-75 78-10 78-92 76-99 IfiflO 15-80 1779 17-94 18-02 18-88 6-00 400 4-73 3-38 4-49 4-47 3-12 4-136 2-67 1-00 ...a 0-67 0-40 0-48 98-74 98-18 99-51 100-51 10071 100-00 Seybert, Brazil. Do. Connecticut Thomson, Do. Awdejew, Brazil, G. = 3 7337. Do. Ural, G. = 3-689. Damour, Connecticut, (m. of 3.) (a) + 0-36 chrome oxide, and 0*29 copper and lead oxide ; (b) peroxide. Seybert first observed glucina in this mineral, whilst Thomson's and Awdejew's experiments prove the silica to be only incidental. The peroxide of iron replaces part of the alumina, the protoxide of the glucina. Occurs chiefly in loose grains in the sand of rivers with other gems in Brazil, Ceylon, and other parts of India. At Haddam in Connec- ticut, and Saratoga in New York, it is found in granite with tourma- line, garnet and beryl. Fine large crystals of a green colour, but hya- cinth-red in one direction, are found with emerald in mica slate on the Takowaja, 180 versts east of Katharinenburg. In this mineral Sir D. Brewster observed fluids in cavities so minute, that 30,000 were contained in a specimen one-seventh of an inch square. Chry- soberyl, when large and transparent, is used as a gem, the opalescent varieties, named cymophane (floating light), being most valued. Family.'] TOPAZ. 255 M M 165. TOPAZ, Phillips, Werner, Hauy ; Prismatic Topaz, Mohs, Jameson. Rhombic ; o>P (M) 124 19', 2Poo (w) 93, ooP2 (/) 93 8', and numerous other forms, among which P (o) generally occurs. The Fig. 150. character of the crystals is always prismatic (fig. 150), from the prevalence of the above prisms, which are bounded at the extremities by vari- ous forms, especially OP, P, f P2 0), or 2Poo . The crystals are often hemimorphic, being attached by one end singly or in druses. The prisms are finely striated. Also found massive, with indistinct crystalline structure, and disseminated in rounded fragments. Cleav- age, basal very perfect, traces in several other directions, especially along M and / in the Scottish varieties. Fracture conchoidal or un- even. H. = 8 ; G. = 3-4 3-6. Transparent to translucent on the edges. Lustre vitreous. Colourless, but coloured yellowish, reddish, or greenish- white, honey- yellow, hyacinth-red, violet-blue, and mountain or asparagus- green. Becomes electric from heat or friction. Strongly heated in the closed tube with salt of phosphorus, or in the open tube when fused with carbonate of soda, shows reaction for fluorine. B.B. infusible alone, but in a strong heat small blisters form on the surface. With borax melts slowly to a clear glass ; with cobalt solution the powder be- comes blue. Not affected by hydrochloric acid, but by long digestion in sulphuric acid, gives traces of fluorine. Chem. com., according to Rammelsberg, a combination of silico-fluoride of aluminium (Kiesel- fluoraluminium) with silicate of alumina, or 12 A! si + (2 Al F 3 -f- 3 Si F 2 ), which gives in 100 parts 35*26 silica, 54'93 alumina, and 17*14 fluorine (= 107*33) ; the overplus arising from the silicium and aluminium being considered as the earths. The latter member may be regarded as equivalent to jjj 2 si 3 , with the oxygen replaced by fluorine. Analyses, next page. Canton placed the chief electric poles of the topaz in the extremi- ties of the prism. Hankel found four weaker poles, two in the obtuse, and two in the acute side edges ; and Erman remarked that the electric axis did not coincide with that of the prism. P. Riess and G. Rose state that the two antilogue poles are situated in the obtuse side edges of the prism (o>P) ; whilst the two analogue poles unite in the middle of the diagonal joining these edges, or correspond to the 1 macrodiagonal chief section. Many topazes contain small ca- 256 TOPAZ, [Gems Silica. Alu- mina. Fluoric acid. Total. A B A B 1 2 34-24 34-01 57-45 58-38 7-75 7-79 14-99 15-06 99-44 100-18 106-68 107-45 Berzelius, Saxony. Do. Brazil (yellow). 3 4 34-36 5774 54-88 777 17-33 1502 16-50 99-87 107-12 Do. Finbo (Pyrophysalite). Forchhammer, Brazil. B 35-39 55-96 1735 16-86 108-70 108-21 Do. Trumbull, Connecticut. G 35-66 55-16 1779 17-84 108-61 108-66 Do. Finbo (Pyrophysalite). In Nos. 1-3, A is the fluoric acid given by Berzelius ; B as corrected from the new atomic numbers by Rammelsberg. InTsos. 4-6, A and B are fluorine, the latter estimated from the loss, when the topaz was heated to the temperature at which cast iron melts. vities filled with the peculiar fluids described by Sir D. Brewster. In others from Brazil he found a white, earthy substance, composed, according to Berzelius, of silica, alumina, lime, and water, and intu- mescing like zeolite before the blowpipe. Topaz occurs chiefly in granite, but also in gneiss, mica-slate, and clay-slate. It is generally crystallized in druses, often accompanied by rock-crystal, and not uncommonly the one enclosed in the other, as in a specimen of Siberian topaz in the Museum of Mines at St Petersburg!!, which contains a crystal of smoke-coloured rock-crystal, and weighs about thirty-two pounds. It is also frequently associated with tourmaline, beryl, and euclase, or with fluor-spar, lepidolite, and other minerals containing fluorine. The topaz -rock of Schneckenstein near Auerbach in Saxony, is a granular slaty mixture of quartz, schorl, and topaz, containing druses with crystals of quartz and topaz, with lithomarge. It is also found in several of the tin mines of Bohemia, Saxony, and Cornwall (St Michael's Mount), with crystals of quartz, lepidolite, tin, and fluor spar. The topazes of commerce come chiefly from Brazil and Siberia. In the former they are found in Minas Novas and Minas Geraes, near Villa Ricca in nests of quartz with euclase and lithomarge, also near Rio Janeiro in loose sand with diamonds. The principal Sibe- rian localities are Alabaschka near Mursinsk, the Hmen Mountains, and the mountains near Nertschinsk. Kamtschatka, Asia Minor, Ceylon, New Holland, Peru, Trumbull and Middleton in Connecticut, are other localities. Small crystals have been found in the Mourne Mountains in Ireland. Some of the finest crystals are from the Cairngoruin Mountains in Aberdeenshire, where one was found weigh- ing nineteen ounces. Some from this locality are sky-blue, except on the acute edges of the prism, which are pale-brown. The common or coarse columnar topaz is named Pyrophysalite ; and is found in granite veins in gneiss at Finbo, and in loose blocks Family.] PYCNITE LEUCOPHANE. 257 at Broddbo near Fahltra. One crystal from the latter place in the College of Mines at Stockholm weighs eighty pounds. Topaz is highly valued as an ornamental stone. The Brazilian are distinguished for deep yellow tints, but are changed by exposure to heat to pale-pink or red, like the Balas ruby, from which they are easily known by their electricity. In the Saxon topazes, pale wine- yellow prevails, but they become limpid from heat. The Mursinsk topaz has a peculiar bluish tinge. With these peculiarities of colour, others in crystalline form are associated. The purest from Brazil, named Goutte tfeau, when cut in facets like the diamond, closely re- semble it in lustre and brilliance. The topazion of the ancients seems to have been a different mineral 166. PYCNITE, Hauy ; Stangenstein ; Schorlite. Massive, with a parallel columnar structure, and oblique transverse divisions, or cleavage. H. = 7*5 ; G. = 3-49 3*54. Translucent ; lustre vitreous ; colours straw-yellow to yellowish and reddish-white. Chem. com. 2 A i 5 si 6 + (2 AI F 3 + 3Si F 2 ) or topaz with two atoms less of alumina. Analyses. 2 Silica. Alu- mina. Fluorine Total. 38-43 39-04 51-00 51-25 17'095a 18-48 106-525 10877 Berzelius, Altenberg Saxony. Forchhammer, Do. (a) Fluoric acid, Rammelsberg (8'84, Berzelius). In most physical characters this mineral agrees with topaz, of which it is usually considered a variety. But the above analyses show that it differs in composition ; and Forchhammer thinks its structure indi- cates a monoclinohedric crystallization. Hausmann, however, affirms that the oblique divisions are not true cleavage planes, that the angles of the prism do not differ from those in topaz, and that like this mi- neral it has a perfect cleavage perpendicular to the axis of the prism. It occurs in the tin mines at Altenberg in Saxony, and at Schlacken- wald, and Zinnwald in Bohemia, with quartz and lepidolite. 167. LEUCOPHANE, Esmark. Triclinohedric (?) ; but crystals rare. They are tabular, and seem formed by OP, oo'P', ooPoo , and ooPoo . Mostly massive and colum- nar. Cleavage in three directions, of which two intersect at 53 25, (in two directions intersecting at 80, Weibye). Very difficultly frangible. H. = 3'5 4 ; G. = 2-974. In thin splinters, translu- cent or transparent, and almost colourless, in thicker pieces wine- 258 EUCLASE. {Gems yellow or olive -green ; lustre vitreous or resinous. B.B. fuses to a pale violet-blue bead ; with borax to an amytliest-coloured bead from manganese. In the open tube with salt of phosphorus gives reaction for fluorine. Chem. com. 3 ca si + c'a 3 si 2 + Na F. Analysis by Erdmann, 47'82 silica, 25-00 lime, 11-51 glucina, 1-01 manganese protoxide, 7'59 sodium, 0'26 potassium, 6'] 7 fluorine (= 99 -36). Found imbedded in syenite on the Lambskjier near Brevig in Norway. 168. EUCLASE, Hauy y Phillips ; Euklas, Werner ; Prismatic emerald, Jameson, Mohs. Monoclinohedric ; C = 71 7', ooP 114 50', P 105 59', Poo 49 17'; the combinations are frequently very complex, with many prisms and hemipyramids, but generally consist essentially of ocP (S) . ( ooPoo ) (T) . P GO (fig. 151). Cleavage, clinodiagonal highly Fig. 151. perfect ; hemidomatic along Poo less so ; orthodiagonal in traces. Very brittle and fragile. Fracture conchoidal. H. = 7*5 ; G. = 3 3*1. Transparent ; lustre splendent vitreous. Colour pale moun- tain-green, passing into yellow, blue, or white. B.B. in a strong heat intumesces, becomes white, and melts in thin splinters to a white enamel. With borax forms a colourless glass. Not affected Jby acids. Chem. com. i 4 si 3 + 6 6 2 si, with 43-9 silica, 32-2 alu- mina, and 23-9 glucina. Analysis of a specimen from Brazil, by Berzelius : 43'22 silica, 30'56 alumina, 21-78 glucina, 2-22 iron per- oxide, 0'70 tin oxide (= 98-48). Euclase, named from its extreme frangibility, is a rare mineral. Family.'] EMERALD. 259 It was first brought from Peru, where it is said to occur in loose crystals, but has since been found in Brazil, at Boa Vista, and Capao do Lane, according to Eschwege, in druses of chlorite slate, with rock crystal, topaz, and lithomarge. More recently with the topaz at Trumbull, Connecticut ; and also, it is said, at Lake Baikal in Siberia. Euclase will take a fine polish, but its extreme fragility prevents its employment as an ornamental stone. 169. EMERALD, BERYL, Phillips, fyc. ; Emeraude, Hauy ; Schmaragd, Beryl, Werner, fyc. ; Dirhombohedral Emerald, Mo/is. Hexagonal ; P 59 58'. The more usual forms are o>P, OP, ooP2, P, and 2P2, and the most common combinations ooP . OP, and ooP . ooP2 Fig. 152. . OP (fig. 152). The crystals appear prismatic, and gene- rally with vertical striae. It is more rare in columnar ag- gregates. Cleavage, basal rather perfect ; prismatic along ooP imperfect. H. = 7'5 8 ; G. = 2-6 2'8. Tran- sparent or translucent. Lustre vitreous. Colourless or white, but generally coloured, of various green shades, sometimes very brilliant, also yellow, and smalt-blue. B.B. melts with difficulty on the edges to an obscure vesicular glass ; with borax forms a clear glass ; slowly soluble in salt of phosphorus without leaving silica ; and with fluor-spar forms a bead, colourless when hot, opaque and pale-green when cold. Not affected by acids. Chem. com. ji si 3 + 36 si, or 67*5 silica, 187 alumina, and 13 '8 glucina. Analyses. I Silica. Alu- mina. Glu- cina. Lime. Chrome oxide. Iron jerox. Tantalic acid. Total. ! 64-40 14-00 13-00 2-56 3-50 9756 Vauquelin, Peru. 2 68-50 15-75 1250 0-25 0-30 1-00 98-30 Klaproth, Do. 3 66-45 1675 15-50 0-60 99-30 Do. Siberia. 4 68-35 17-60 13-13 ... 072 072 100-52 Berzelius, Broddbo. 5 67-00 1964 12-56 0-'l8 0-53 99-91 Scheerer, Possum. 6 66-Hf) 18-41 12-54 2-00 99-81 Thomson, Siberia. 7 6970 16-83 13-39 0-24 ; 100-16 C. Gmelin, Broddbo. 8 67-54 17-63 13-51 * ( 9868 Do. Limoges. 9 67-36 16-46 12-75 I'-'sO > 28 98-35 Moberg, Somero, Finnland 10 <;<;< u 16-51 12-75 3-03 0-10 99-01 Do. Tamela, Do. 11 69-51 14-49 15-41a 1'646 ... 101-05 Schlieper, S. America. fa) With alumina ; (6) with magnesia. The rich deep-green varieties, coloured by chrome, Nos. 1 , 2, are named emerald ; the less brilliant or colourless, beryl. The Smarag- dus of the ancients probably included malachite and the plasma or green quartz. They are said to have procured this stone from the Zabarah mines in Upper Egypt, but these, when recently reopened, 260 PHENAKITE. [Gems yielded no emeralds of any value. The Beryllus of Pliny seems more certainly the modern stone of that name. It was in this mineral that Vauquelin in 1797 discovered glucina. Emerald occurs either imbedded or in druses in the crystalline rocks, especially granite, gneiss, mica, and talc slates. The noble emerald was first found in Peru in the Tunka valley near New Car- thage, in veins in clay slate, hornblende slate, and granite, along with calc-spar, quartz, and pyrites. Less beautiful varieties have been since procured from mica-slate in the Heubach valley in Salz- burg, and at Cangarjum in India, and more recently large crystals, but seldom wholly pure, along with phenakite and chrysoberyl on the Takowaya, east of Katharinenburg in Siberia. Allan mentions a crystal from Peru in the collection of the Duke of Devonshire above two inches long, weighing 8 oz. 18 dwts., and valued at 150 guineas, though containing numerous flaws ; a perfect hexagonal prism in his father's collection measured an inch in each direction ; and a cut crystal weighing six ounces in the possession of Mr Hope of London, which cost L.500, and was supposed to be the finest in Britain. The finest Beryls or Aquamarine are found near Mursinsk, and Slatoust, in the Ilmen Mountains, and near Nertschinsk in Siberia, chiefly in druses or veins in granite along with rock crystal or tour- maline and topaz. Some crystals exceed a foot in length. Large crystals also occur in the United States, and one from Ackworth in New Hampshire, measured four feet long, five and a half inches across the faces, and weighed 238 Ibs. Others smaller are found at Royal- ston in Massachusetts, Haddam in Connecticut, and many other lo- calities. Fine crystals occur in granite in the Mourne Mountains in Ireland, and, though rarely, in the Cairngorum Mountains in Aber- deenshire. Salzburg and Brazil also yield the precious beryl ; whilst Fahlun in Sweden, Fossnm in Norway, Limoges in France, the Rabenstein near Zwiesel in Bavaria, the Schlakenwald tin mines in Bohemia, and many other places, are known localities of the common variety. Emerald and Beryl are much valued as precious stones. Green glass is often substituted for it, as in the famous Reichenau emerald, and the so-called Holy Cup of Genoa. 170. PHENAKITE, Nordenskiold ; Rhombohedral emerald, Mohs. Rhombohedric ; R 116 40' (115 25' Nord.}, usual combinations R . ooP2, or <*P2 . P2 . R (fig. 153), but frequently with other subordinate forms. Macles with parallel axes and perfectly inter- secting, are also common. The crystals appear rhombohedric, or Family.'} Fig. 153. IOLITE. 261 short prismatic and pyramidal. Cleavage rhombohe- dric along R, and prismatic along coP2, not very dis- tinct. Fracture conchoidal ; H. = 7'5 8 ; G. = 2-97 3. Transparent or translucent ; lustre vitreous. Co- lourless, and white, but coloured wine-yellow or brown. B.B. infusible alone; with borax forms a clear glass ; with cobalt solution becomes dirty bluish-brown. Not affected cina. by acids. Analyses. Chem. com. o 2 , with 55 silica, and 45 glu- 1 2 Silica. Glucina. Mag- nesia. Total. 55-14 64-40 44-47 45-57 tracesa 0-106 99-61 10007 Hartwall, Ural. Bischof, Framont. (a) With alumina; (6) with lime. First found in the mica-slate on the Takowaja, 85 versts east of Katharinenburg, in crystals one or two inches long but generally of simple forms, along with emerald and chrysoberyl. Since near Fra- mont in Alsace in brown iron ore with quartz, and more recently in the Hmen Mountains, east of Miask, with topaz and green felspar in granite veins in miascite. The crystals from Framont are small, but with many faces, and remarkable for their peculiar hemihedric, hemi- morphic, and macled forms. The llmen crystals are also small, with many faces, but regular forms and no trace of macles or hemimor- phism. When polished, phenakite forms a very splendent orna- mental stone. 171. IOLITE, Werner, Jameson, Phillips; Cordierite, Hauy; Dichroite, Cordier, Hausmann ; Prismatic quartz, Mohs. Rhombic ; o>P 119 10' (Breithaupf), middle edges of P about 125. Fig. 154. Some of the more common combinations are ooP (T) . ooPoo (1) . OP(M), and this withooPoo (A), coP3 (d), Px> (w), and |P 0), or other forms (fig. 154). The crystals, often indistinctly formed, are short, prismatic, resembling hexagonal or twelve- sided prisms, and frequently exhibit a foliated structure along OP. Cleavage, brachydiagonal rather distinct, traces along Poo . Fracture con- choidal or uneven. H. = 77.5 ; G. = 2'5 2'7. Transparent or translucent ; lustre vitreous, in- clining to resinous ; colourless, but coloured in many shades of blue, green, brown, yellow, and 262 IOLITE. [Gems grey. Many varieties show a distinct pleochroism. B.B. fuses slowly to a clear glass ; slowly soluble in borax and salt of phosphorus ; with cobalt solution forms a blue or bluish-grey glass. Slightly affected by acids. Chem. com. Ai 2 si 3 + 2 M g si = 52 silica, 34-5 alumina, and 13-5 magnesia, but the latter partly replaced by protoxide of iron or manganese. Analyses. Silica. Alu- mina. Mag- n.esia. Iron protx. Mang. protx. Loss by heat. Total. 1 48-35 31-71 10-16 8-32 0-33 0-60 9940 Stromeyer, Bodenmais, Bavaria. 2 49-17 33-11 11-45 4-34 0-04 1-20 99-31 Do. Simiutak, Greenland. 3 48-54 31-37 11-31 5-69 0-70 1-69 9!C65 Do. Orrijerfvi, Finnland. 4 50-25 32-42 10-85 4-00 068a 1-66 9987 Do. Fahlun. 5 48-53 31-50 15-00 1-61 0-24 1-71 98-59 Thomson, Orrijerfvi. 6 49-62 2872 8-64 11-58 1-51 ... & 100-30 Do Connecticut. 7 48-6 30-5 8-2 107 o-i 15 c 100-8 Schiitz, Finspang, E. Gothland. 8 48-35 32-50 10-00 6-00 1-10 3-10 100-05 Jackson, Haddam, Connecticut. 9 48-15 32-50 10-14 792 0-28 0-50 99-49 Do. Unity, N. Hampshire. 10 50-44 32-95 1276 l-07 l-02d 99-36 Scheerer, Krageroe, Norway. (a) Peroxide; (6) +0-23 lime; (c) + 0-2 undecomposed ; (d) +1-12 lime. This mineral was first described by Cordier, who thought its crys- tallization hexagonal, and named it dichroite from the change of co- lours. It however presents three tints, or dark-blue along the chief axis, lighter blue in an oblique direction, and colourless, or greyish or brownish -yellow, at right angles. Haidinger distinguishes even six tints in different positions. Plates cut either parallel or at right angles to the axis polarize light like tourmaline. It was first found in granite at Cabo de Gata in Spain with quartz and garnet. After- wards in fine imbedded crystals or massive (Peliorn) at Bodenmais in Bavaria with magnetic pyrites, copper pyrites, zinc blende, and mica ; and at Orrijerfvi (the Steiriheilite) with copper pyrites. Also in quarz and gneiss near Tvedestrand and Brevig in Norway, and in several places in Sweden, whence it has been transported with the granite boulders to Northern Germany. Hard fahlunite is a red- dish-brown massive variety (No. 4) from Fahlun. It also occurs in Greenland, North America, and Siberia. Small rolled masses of an intense blue colour and transparent, found in Ceylon, are the sapphire d'eau or Luchssapphir of the jewellers, but are not highly valued. It is also said to occur in the trachyte of Lake Laach on the Rhine. The following minerals have been often considered distinct spe- cies, but seem to want the definite crystalline and chemical characters that would entitle them to this rank. Haidinger, Dana, and others consider them with more probability as mere pseudomorphs of iolite. They are essentially silicates of alumina, and another base, often iron Family.] IOLITE. 263 protoxide, but mixed with many other substances. In some the water seems incidental, absorbed during decomposition, when the iron also passes into the peroxide. (a) Bonsdorfite (Thomson, Min. p. 323), Hydrous lolite (Ib. p. 278), greenish -brown, or dark olive-green ; found near Abo with iolite, from which it only differs in containing 4 atoms of water. No. 1 is only an approximation, the exact numbers having been lost O iu a fire at Abo. (b) Esmarkite of Erdmann, Chlorophyllite of Jackson, occur in large 4, 6, 8, or 12 sided prisms, or in foliated masses of a green or brownish colour, contain less water, or only 2 atoms. The former is found at Brakke near Brevig in Norway (anal. No. 2) ; the latter at Unity in Maine (No. 3) ; and Haddam in Connecticut, where it sometimes contains the unaltered iolite in the interior. It shows mere traces of phosphoric acid. (c) Fahlunite of Hisinger, Triclasite of Hauy ; compact, green or brown, with a conchoidal or uneven fracture. H. = 2 a o 3 ; G-. _ 2-5 2*8. It occurs in the talc and chlorite slates at Fahlun, and a foliated variety with a threefold cleavage in the deepest part (190 fathoms) of the copper mines. Analyses Nos. 4, 5 (compact, brownish-green), 6 (black, foliated), 7 (crystallized). (d) Weissite, externally like fahlunite, but said to be monoclino- hedric ; occurs in kidney-shaped masses with indistinct cleavage, and ash-grey or brown colours, at Fahlun (No. 8), and in Lower Canada (No. 9). (e) Finite of Werner and Hauy, Giesechite ofSowerby ; crystallized Silica. Alu- mina. Mag- nesia. Iron prot. Mang. prot. Lime. ) Soda. Pot- ash. Watr. Total. 1 45 30 9 5 ... ... 11 100 Bonsdorff. 2 45-97 32-08 10-32 3-83 0-41 : 45a 5-49 98-55 Erdmann. 3 45-20 27-60 9-60 8-24 4-08 ... ... 3-60 98-32 Jackson. 4 46-79 26-73 2-97 5-01 0-43& .. ... 13-50 95-43 Hisinger. 5 43-51 25-81 6-53 6'35& 1-72 trace 4-45 0-94 11-66C 101-13 Trolle-Wachtmeis- 6 44-60 30-10 6-75 3-86 2-24 1-35 trace 1-98 9-35d 100-23 Do. [ter. 7 44-95 30-70 6-04 7-22 1-90 0-95 1-38 8-65d 101-79 Do. 8 59-69 2170 899 1-43 0-63 O'O'S 4-10 3-20 e 10072 Do. 9 55-05 22-60 570 12-60 trace l'-40 2-25 99-GO Tennant. 10 55-96 25-48 3-76 5-51& 0-39 7 : 89 1-41 slag from Blomfield Iron Works, Tipton. 174. CHONDRODITE, cTOhsson; Condrodite, Phillips, Hauy ; Maclu- rite, Seybert ; Brucite, Gibbs ; Heraiprismatic Chrysolite, Mohs. Monoclinohedric, according to Dana ; o>P 63, P 80, P 89 ; rarely in distinct crystals, chiefly in round imbedded grains or granu- lar aggregates. Cleavage indistinct ; fracture imperfect conchoidal ; H. = 6-5 ; G. = 3-15 3-25. Transparent or translucent. Lustre vitreous or resinous. Colour straw or orange-yellow, hyacinth-red, brown, green, and almost black. Streak white or yellowish. B.B. becomes opaque, milk-white or brownish, and fuses on very thin edges. With borax fuses slowly to a clear glass slightly tinged by iron. In open tube, with salt of phosphorus, shows traces of fluorine. Decomposed by acids. Chem. com. 3 M g 2 si + Mg F = 37'28 silica, 50'06 magnesia, 5*11 magnesium, 7'55 fluorine ; or, in analysis, 58-40 magnesia. Analyses. Silica. Mag- nesia. Iron protox. Potash. Fluo- rine. Watr. Total. 1 32-67 2 36-00 54-00 53-64 2-33 a 3-97 a 2-11 4-096 3-756 1-00 1-62 96-19 98-98 Seybert, New Jersey. Thomson, Eden, New York. 3 33-06 4 33-97 55-46 56-97 3-65 3-48 ... 7-60 7-44 ... 99-77 101-68 Kammelsberg, N. America (yellow). Do. Do. Do. 5 33-10 56-61 2-35 8-69 100-75 Do. Pargas, Do. 6 33-19 54-50 6'75 ... 9-69 104-13 Do. Do. (grey). (a) Peroxide ; (6) fluoric acid. Chondrodite occurs in granular limestone at Pargas in Finnland, Aker, and Gullsjo in Sweden. In a similar position in several parts of North America, as near Sparta in Sussex county in New Jersey, and in Orange county in New York. It has also been found in a bed of magnetic iron ore in gneiss, imbedded in dolomite or bitter- spar in the Taberg in Wermeland. Also in Saxony ; and with mag- netic and arsenical pyrites on Loch Ness in Scotland. The Humite of Bournon, from the ejected masses of Monte Somma, 272 LIEVHITE. [Metallic Stones is considered as chondrodite by Monticelli and Covelli, a view con- firmed by G. Eose, who finds fluorine in it, and considers its crystal- lization as monoclinohedric. It has a perfect cleavage in one direc- tion ; is transparent ; vitreous ; brown, yellow, or almost white ; scratches glass ; and B.B. infusible. Its composition is unknown ; and the crystallization both of it and chondrodite need further inves- tigation. XII. FAMILY. METALLIC STONES. 175. LIEVRITE, Werner, Jameson; Yenite, Phillips; Ilvaite, Hausmann ; Diprismatic Melan-ore, Mohs. Ehombic ; P, polar edges 138 26' and 117 34', ooP 111 12', Poo 112 40'; usual combinations ooP . P, ooP2. o>P . P . Poo, and Fig. 158. ooP2 0) . P (o) . Poo (d) (fig. 158). The crys- tals are generally long prismatic, vertically striated and attached. It also occurs in radiated columnar or fibrous masses, rarely granular. Cleavage, in several directions all imperfect ; fracture conchoidal or uneven ; brittle ; H. = 5'5 6 ; G. = 3'9 4-2. Opaque, resinous or imperfect metallic; colour brownish or greenish-black; streak black. B.B. fuses easily to a black magnetic globule ; with borax to a dark-green glass. Soluble in hydro- chloric acid, forming a yellow jelly. Chem. com. j-e 2 si + 3 Fe 2 si + c'a 3 si 2 , or 28-8 silica, 24-8 iron peroxide, 33*4 iron protoxide, and 13'0 lime. Silica. Iron perox. Iron prot. Mang. prot. Lime. Alu- mina. Watr. Total. 1 30-0 57'5 12-5 100-00 Vauquelin, Elba. 2 28 '0 55 '0 30 12-0 0-6 98-6 Collet-Descotils, Do. 3 4 5 6 29 '2 8 29-28 29-83 34-60 23 : 00 42 : 38 52-54 31-90 52 '68 15-78 1-59 1-59 1-51 0-28a 13-78 13-78 32-44 5-84 0-61 0-61 V 12 1-27 1-27 1-60 1-00 99-07 101-43 98-06 100-00 Stromeyer, Do. Do. cor. by v. Kobell, Do. Bammelsberg, Do. Wehrle, Hungary. (a) Peroxide. In other trials Kammelsberg found the Iron protoxide = 30'73 Iron peroxide = 24'58 33-074 22-800 niSINGERITE ANTHOSIDERITE. 273 Family.] and calculates the proportion as 33'06 to 24-56. He also found no alumina, and considered the water as merely hygroscopic. Lievrite occurs in beds among the crystalline strata along with tremolite, quartz, magnetic ironstone, copper pyrites, and other ores. It was first found in Elba in Monte Fico or Rio la Marina. Also near Fossum in Norway, Kupferberg in Silesia, Rhode Island in North America, and in Greenland. It was named Yenite in commemoration of the battle of Jena in 1806 ; Ilvaite from Elba, and Lievrite from its discoverer Le Lievre. Wehrlite, v. Kobell (No. 6) ; iron-black, with greenish-grey streak ; slightly magnetic, and B.B. difficultly fusible ; seems a variety of Lievrite. It is found near Szurrasko in Hungary, with brown iron ore, probably as a vein in greenstone. 176. HISINGERITE, Berzelius, Mohs ; Thraulite, v. Kobell. Massive and reniform, with rough surfaces ; or compact in concen- tric crusts. Fracture conchoidal ; brittle ; H. = 3'5 4 ; G. = 2'6 3. Opaque ; resinous ; colour brownish or bluish-black ; streak liver or yellowish-brown ; in the closed tube yields water. B.B. on charcoal fuses with difficulty to a steel-grey or black magnetic bead. Soluble in acids, leaving slimy silica. Chem. com. perhaps re si + 4 H, if the iron all the peroxide. Analyses. Silica. Alu- mina. Iron proto- perox. Mang. perox. Watr, Total. 1 2 27-50 36-30 5-50 51-50 44-39 0-77 11-75 20-70 97-00 101-39 Berzelius, Gillinge. Histnger,Riddarhyttan. 3 3177 49-87 20-00 101-64 Do. Bodenmais. 4 31-28 ... 49-12 ... 19-12 99-52 v. Kobell, Do. (a) Peroxide. Occurs in cavities of calc-spar in the iron mine of Gillinge in Suder- manland, and at Rydarhyttan in Sweden ; and with magnetic pyrites at Bodenmais in Bavaria (thraulite). The Polyhydritc of Breithaupt, from Breitenbrun Saxony, seems also this rather rare mineral. 177. ANTHOSIDERITE, Hausmann. Massive, in fine fibrous, flower-like aggregates ; very tough ; H. = 6-5 ; G. = 3. Opaque, or in thin fragments translucent ; silky lustre ; colour ochre-yellow to yellowish-brown. B.B. becomes reddish- brown, then black, and fuses with difficulty to a black magnetic slag. Soluble in hydrochloric acid. Chem. com. p e si 4 + H. Analyses, next page. 274 NONTRONITE PINGUITE CHLOROPAL. [Metallic StOTltS Silica. Iron perox. Watr. Total. 2 61-14 59-03 34-63 35-35 3-59 3-59 99-36 97-97 Schnedermann. Do. Occurs in beds of magnetic iron at Antonio Pereira in Minas Geraes, Brazil. 178. NONTRONITE, Berthier. Massive, or in nodules. Fracture uneven splintery. Soft ; G. = 2-08. Opaque, but in water becomes partially translucent, the air being evolved in globules. Lustre dull or glimmering. Streak resinous. Colour straw-yellow, yellowish-white, or siskin-green. B.B. decre- pitates, then becomes yellow, brown, and lastly black, and magnetic, but without fusing. Soluble ; and gelatinizes in warm acids. Chem. com. nearly PC si 3 + 5 H = 43 silica, 36 iron peroxide, and 21 water. Analyses. Silica. Alu- mina. Iron perox. Watr. Mag- nesia. Clay. Total. 1 2 3 4 440 40-68 41-31 41-10 3-6 3-96 3-31 29-0 3019 35-69 37-30 18-7 23-00 18-63 21-56 2-1 237 0-1 ... a o-i 97-5 100-20 100-03 99-96 Berthier, Nontron, Dordogne. Dufrenoy, Villefranche. Jacquelin, Montmort. Biewend, Autun. (a) + 0-19 lime, and 0-90 copper protoxide. 179. PINGUITE, Breithaupt. Massive ; fracture flat conchoidal, or uneven and splintery. Very sectile ; H. = 1 ; G. = 2-3 2-35. Opaque or semitranslucent. Glimmering resinous lustre. Colour siskin or dark oil-green. Streak lighter. Feels very greasy ; does not adhere to the tongue. In the closed tube yields much water. B.B. fuses only on the edges. With salt of phosphorus gives colour of iron, and leaves silica. Soluble in hydrochloric acid, depositing siliceous powder. Chem. com. 2 p4 si 2 + Fe si 2 + 14 H. The following is the analysis of a specimen from Wolkenstein, by Kersten : 36'90 silica, 29-50 iron peroxide, 610 iron protoxide, 0'45 magnesia, 1-80 alumina, 0-15 manganese perox- ide, 25-10 water (= 100). Occurs in veins of heavy spar in gneiss, at Wolkenstein and Geils- dorf in Saxony. Also found near Elbingerode in the Harz, in the basalt of the Pflasterkaute, at Tannhof near Zwickau, and at Suhl in the Thuringer Wald. 180. CHLOROPAL, Bucholz. Massive. Fracture conchoidal ; rather brittle. H. =25 3 ; Family.'] CKLOROPH^EITE THORITE. 275 G. = 2-1 2-2. Translucent on the edges ; lustre dull or glim- mering ; colour siskin or pistacio-green ; streak lighter and glisten- ing. B.B. infusible, but becomes first black, then brown, and shows reaction for iron with fluxes. Partially soluble in hydrochloric acid. Analyses. 1 2 3 Silica. Iron perox Mag- nesia. Alu- mina. Watr. Total. 46 45-00 41-10 33 32-00 37-30 2 2-00 1 075 18 20-00 21-56 100 9975 99-96 Brandes, Unghwar. Do. Do. Biewend, Andreasberg. Found in Hungary with semiopal, and in the Harz. It showed also traces of potash, and in No. 1 of manganese peroxide. From its action before the blow-pipe, the iron is probably the protoxide, and chem. com. Fe 2 si 3 + 4 H- 181. CHLOROPH^EITE, Macculloch, fyc. Massive and disseminated. Apparent cleavage in two directions. Fracture conchoidal, earthy. Very soft and sectile. G. = 2*02. When first exposed, translucent, and pistacio or olive-green ; but soon changes to brown or black, and becomes opaque. B.B. melts to a black glass. With borax gives colour from iron. Chem. com. (Fe , Mg) 3 si 4 4- 18 H. The following is the analysis of a specimen from Faroe, by Forchhammer : 32-85 silica, 22-08 iron protoxide, 3 '44 magnesia, and 41-63 water (= 100). Discovered by Dr Macculloch in the amygdaloidal trap of Scuir More in Rum. Since found at Qualboe on Suderoe in Faroe, and in Iceland. Also in Fife, and near Newcastle ; and in America at Gill in Massachusetts, and Southbury in Connecticut. 182. THORITE, Berzelius. Massive ; fracture conchoidal, hard and brittle. G. = 4 -63 4'8. Opaque, rarely translucent on the edges ; splendent vitreous ; red- dish-brown, or black clouded with red ; streak dark-brown. In the closed tube gives water, and becomes brownish-red. B.B. infusible; with salt of phosphorus leaves silica ; with soda on platina wire shows reaction for manganese. Gelatinizes with hydrochloric acid. Chem. com. essentially Th 2 8 + 2n = 73-4 thorina, 16'8 silica, and 9 '8 water, but combined with very many other silicates. Analysis by Berzelius, 18'98 silica, 57'91 thorina, 2*58 lime, 3-40 iron peroxide, 2-39 manganese peroxide, 0'36 magnesia, 1*61 uranium oxide, 0'80 276 EULYTINE GADOLINITE. [Metallic Stones lead oxide, O'Ol tin oxide, 0-] 4 potash, O'lO soda, 0'06 alumina, 9'50 water, and 1'70 undissolved mineral (= 99*54). In this mineral Berzelius discovered the metal thorium. It is found in the island Lowo near Brevig in Norway, imbedded in syenite or compact analcime, and invested with a brown crust. 183. EULYTINE, Breithaupt; Kieselwismuth, Naumann; Silicate of Bismuth, Thomson; Bismuth Blende, Dana; Dodecahedral Diamond Blende, Mohs. Tesseral and tetrahedral ; usual forms ?2? and ?P_ 2 with other 2 2 faces. The crystals (sometimes like fig. 12, p. 1 3) are very small, often with curved faces, and attached singly or united in small druses and spherical groups. Cleavage, dodecahedral very imperfect ; frac- ture conchoidal. H. = 4'5 5 ; G. = 5'9 6. Transparent and translucent ; adamantine ; clove or yellowish-brown, yellowish- grey or white. Streak white or grey. B.B. fuses readily with intumes- cence to a brown bead, leaving a yellow ring on the charcoal ; with soda gives metallic bismuth ; with salt of phosphorus leaves silica. Decomposed by hydrochloric acid, forming gelatinous silica. Chem. com. probably "m si 2 with some phosphate of iron. Analyses. Silica. Bism. perox Phos. acid. Iron perox Mang. perox Watr. Fluor, acid. Alu- mina. Total. 1 2 22-23 50-24 69-38 13-03 3-31 9-62 2-40 10-54C 0-30 trace 1-Ola 1-37& 14 ! 65 100 98-08 Kersten (m. of 2.) Schiiler. (a) With fluoric acid ; (6) with loss ; (c) protoxide. Found with quartz and bismuth at Schneeberg, and also at Brauns- dorf near Freiberg. No. 2 is the Hypochlorite of Schiller, or Green iron-earth, also from Schneeberg. It forms crypto-crystalline reni- form crusts, or very fine, almost compact, earthy aggregates, semi- translucent or opaque ; dull, and siskin or olive-green. H. = 6 ; G. = 2'9 3. B.B. infusible, but becomes blackish-brown ; and forms a yellow ring on the charcoal. Insoluble in acids. It seems a mixture of silicate of iron and bismuth, with phosphate of alumina. 184. GADOLINITE, Ekeberg, Phillips, Hauy ; Hemiprismatic Melan-ore, Mohs. Monoclinohedric ; according to Scheerer Poo 49, ceP 115, (2Poo) 70f nearly. The crystals, rare and indistinct, seem a combination of these forms, and appear prismatic from prevalence of ooP. Chiefly massive and disseminated. Cleavage very indistinct or impercepti- ble. Fracture conchoidal, or uneven and splintery. H. = 6'5 ; Family.] ALLAN1TE. 277 G. = 4'0 4'4. Opaque or translucent on the edges. Lustre vi- treous, often resinous. Colour pitch-black or greenish-black ; streak greenish-grey. Sometimes magnetic. B.B. the conchoidal (vitreous) varieties incandesce vividly, intumesce but do not fuse : the splintery- varieties form cauliflower-like ramifications, but do not incandesce. Some fuse difficultly on thin edges. Gelatinizes in hydrochloric acid. Chein. com. very uncertain, but generally R S si , in which R is yttria, protoxide of iron, protoxide of cerium, or glucina in various propor- tions. Analyses. Silica. Yttria Cerm. prot. Iron prot. Mag. nesia. Lime. Glu- cina. Watr. &c. Total. 1 25-80 45-00 16-69 10-26 ... ... 0-606 98-35 Berzelius, Finbo. 2 24-16 45 '93 16-90 11-34 0-606 98-93 Do. Broddbo. 3 29-18 47-30 3-40a 8'OOa l-30c 3-is 2 : 00 5-20 9953 Do. Kararfvet, Fah- 4 24-33 4533 4-33a 13'59a tracec 11-60 0-99 100-17 Thomson. flun. 5 24-65 45-20 4-60a 1455a ... 11-05 0-50 100-55 Richardson. 6 27-00 36-50 14-33a 14-50a 0*50 6-00 98-83 Connell. 7 25-59 44-96 6-'33d, 12-13 0-23 10-18 99-42 Scheerer, Hitteron. 8 24 65 49-60 7-64/ 1 ! 15-03 tracee 0-46 2-13 ... 99-51 Berlin, Ytterby. 9 24-65 51-38 7-99/14-69 129e trace 100-00 Do. Do. 10 24-86 48-32 7'41/j 14-80 0-67e : 67 3-50 ... 100-23 Do. Do. 11 24-85 51-46 5-24/ 13-01 1-lle 0-50 4-80 100-97 Do. Do. (G.-=4-22). (rt) Peroxide; (6) volatile matter; (c) manganese peroxide (d) Lanthanium oxide; (e) magnesia and protoxide of manganese; in 9 also with lime ; (/) peroxide of cerium and lan- thanium. There are several other analyses of this mineral. Of the Ytterby varieties, Nos. 8, 9, 10 intumesced B.B. with weak or no incandes- cence; No. 11 incandesced strongly. According to H. Rose, the incan- descence in gadolinite, and probably in other minerals, is caused by the liberation of specific heat, the quantity in the mineral before and after ignition being different. The crystallization of gadolinite has not been well ascertained. It is named from Gadolin, who, in 1794, found a new earth in it, named Yttria by Ekeberg in 1797. It occurs chiefly in granitic rocks in gneiss, as near Krageroe in Norway, both massive and crystallized (in the form described by Phillips, with oo P CM) 118 nearly, and oo P to P (M : b) 156). At Ytterby in flesh- red felspar with Yttrotantalite ; and at Finbo in granite veins with albite and quartz. It is also said to occur at Disko in Greenland, and in Ceylon. 185. ALLANITE, Thomson; Cerin, Hisinger ; Orthite, Berzelius; Tetartoprismatic, and Prismatoidal, Melau-Ore, Molis. Rhombic, according to G. Rose and Scheerer ; ooP 128, Poo 110, 2 Poo 70 ; distinct crystals rare (fig. 159), mostly in long needle- 278 ALLANITE. [Metallic Stones Fig. 159. shaped or columnar masses, intimately united and indis- tinctly formed ; or granular and compact. Cleavage (along ooP ?) imperfect ; fracture conchoidal or uneven. H. = 6 ; G. = 3-2 3'7. Opaque, or slightly trans- lucent in thin splinters. Lustre imperfect metallic, in- clining to vitreous or resinous. Colour, black inclining to green or brown ; streak greenish or brownish -grey. B.B. frothes, and melts easily to a black or brown scoria (glass, v. Kobell), often magnetic. Gelatinizes with hydrochloric acid. Chem. com. very variable, but, according to Scheerer, generally SR 3 s'i 2 + 2 B s"i, in which R includes the protoxides of cerium, lanthanium, iron, and manganese, with lime, yttria, and magnesia ; R chiefly alumina, with some peroxide of iron. Analyses. Silica. Alu- mina. Ce- rium prot. Lantha nium oxide. Iron prot. Mang. prot. Lime. Yttria Mag- nesia. Water &c. Total. 1 35-4 4-1 31-5 22-8 9-2 ... 4-00 107-0 Thomson. 2 33-02 15-23 21-60 ... 15-10 : 40 11-08 ... 3-00 99-43 Stromeyer. 3 35-15 16-23 13-34 5-80 15-55 0-98 12-02 0-78 0-50 100-35 Scheerer. 4 34 -00 16-40 13-73 ?80 15-51 11-75 0-56 99-75 Do. 5 30-17 11-31 28-19 B 20-72 9-12 ft ...a 100-38 Hisinger. 6 32-06 G'49 23-80 2-45 25-266 8-08 i : i"6 0-fiO 99-90 Scheerer. 7 36-25 14-00 17-39 11-42 T-36 489 3 : 80 870 97-81 Berzelius. 8 32-00 14-80 19-44 .. 12-44 3-40 7-84 3-44 ... 5-36 98'72 Do. 9 34-93 14-26 21-43C ^ 14-90 0-85 10-42 1-91 0-86 0-52 100-08 Scheerer. 10 32-77 14-32 17-70 2-31 14-76 1-12 11-18 0-35 0-50 2-51d 98-28 Do. 11 33-81 13-04 20-50 15-65<; 9-42 1-45 0-38 3'38/ 98-30 Do. 12 32-93 15-54 20-01(7 .. 4-21 : 39 6-76 0-59 215 17'55/z 100-13 Bahr. 13 33'05 15-29 20-5& ... 16-64 l-BBi 10'18 1-18 1-24/t 9971 Berlin. 14 27-59 16-14 n-75/7 ... 16-01 1-55 2-28 2-12 4 : 94 ll'4ft 100-55 Do. 15 35-49 18-21 10-85 6-54 13-03 2-376 9-25 ~ 2-06 2-00 9980 Hermann. (a) + 0'87 copper protoxide ; (b) peroxide; (c) with lanthanium; (d) +0-76 potash; (e) iron and manganese protoxide; (f) + 0*67 potash, and traces of zirconia and titanic acid; (<;) with lanthanium and didymium ; and other faces ; with ooP 140, and the brachydiagonal polar edges of P 152. Cleavage not observable ; fracture conchoidal ; H. = 5 6 ; G. = 5'0 5*15. Opaque, or in very fine splinters translucent yellowish-brown ; colour black ; streak greyish-brown. B.B. decrepitates violently, and when raised to a low red heat incan- desces, and assumes a greyish-brown colour, but is infusible ; with borax forms in the outer flame a yellow, in the inner a brown glass ; slowly and imperfectly soluble in warm hydrochloric acid, wholly in sulphuric acid. Scheerer found that it contains titanic and tantal- lic acids, zirconia, yttria, iron peroxide, uranium oxide, cerium prot- oxide, with a little alumina, traces of lime, magnesia, and perhaps an alkali ; but it is not quantitatively analysed. It differs from poly- mignite in containing tantalium and uranium, with no manganese, and very little lime. Found at Hittero in Norway. 194. PEROWSKITE, G. Rose. Tesseral; in many forms, especially ooOco , O, ooO, several tetrakis- hexahedrons andicositetrahedrons, but generally cubes. Crystals small. Cleavage hexahedral ; H. = 5*5 ; G. = 4. Opaque, or translucent on the edges (brown varieties) ; lustre adamantine ; colour greyish or iron- black, or dark reddish-brown. B.B. infusible ; with borax or salt of phosphorus shows reaction for titanic acid ; slightly affected by acids. Chem. com. da ii, with 58*9 titanic acid and 41-1 lime. Analyses. Titanic acid. Lime. Mag- nesia. Iron protox. with trace of manganese. Total. 1 2 58-96 59-00 39-20 36-76 trace 0-11 2-06 479 100-22 100-07 Jacobson (iron-black). Brooks (dark brown). Found in a bed of chlorite slate near Slatoust in the Ural. 195. AESCHYNITE, Berzelius ; Aechynite, Beudant. Rhombic ; ooP 127 19', 2Poo 73 44' ; usual combination ooP . 2Poo , to which also ooPoo , and sometimes P are joined. The crys- tals are long prismatic (fig. 160), generally very imperfectly formed, 284 MENGITE MONAZITE . [Metallic Stones vertically striated, and imbedded. Cleavage, macrodiagonal only in Fig. 160. traces ; fracture imperfect conchoidal ; H. = 5 5'5 ; G. 4-9 5-1. Opaque or dimly translucent on thin edges ; lustre submetallic or resinous ; iron black or brown ; streak yellowish-brown ; in the closed tube yields water, in the open tube traces of fluoric acid. B.B. swells, and becomes yellow or brown, but is infusible ; with borax and salt of phosphorus shows reaction for titanium, and in red. flame gives with tin a red bead-; not soluble in hydrochloric acid, partially in concentrated sulphuric acid. Analyses. Titan- ic acid Nio- bic acid. Zirco- nia. 1 Iron prof. Ce- rium prot. 15-Oa 2-48 15-59 Lantha- nium oxide. Yttria Lime. Watr. Total. 1 56-0 2 11-94 3 10-56 33-39 3505 20-0 17-52 17-58 2-6 a 17-65 4-32 ...6 4-76 11-13 9-35 4-62 3-8 2-40 1-56C l-66d 97-9 101 -or. 100-51 Hartwall. Hermann, Do. V G. = 4-95> (a) Peroxide; (6) + 0-5 tin oxide; (c) + traces of manganese, magnesia, tungstic acid, and fluorine; (d) with trace of fluorine. Hermann suspects that the titanic acid of Hartwall's analysis con- tained niobic acid, as Berzelius has shown that the mineral he exa- mined was undoubtedly the true aeschynite. The zirconia is of doubtful nature ; it is not thorina, but perhaps the norium earth of Svanberg. Aeschynite occurs near Mask in the Ural, in a granular mixture of felspar, albite, and mica, along with zircon. 196. MENGITE, G. Rose; Ilmenite, Brooke. Rhombic, P with polar edges 150 32' and 101 10', ooP 136 20' ; the crystals, formed by ooP. ooP3 . ooPoc . P, are small, prismatic, and imbedded. Cleavage not observable ; fracture uneven ; H. = 5 5-5 ; G. = 548. Opaque ; semi-metallic lustre ; colour iron-black ; streak chesnut brown. B.B. infusible, but becomes magnetic ; forms a clear glass with borax and salt of phosphorus. Almost wholly solu- ble in warm concentrated sulphuric acid ; scarcely affected by hydro- chloric acid. Not analyzed, but contains zirconia, peroxide of iron, and perhaps titanic acid. It is found in granitic veins in the mias- cite of the Ilmen mountains. It was first described by Mr Brooke, but his name, ilmenite, was already appropriated to another mineral. 197. MONAZITE, Breithaupt ; Mengite, Brooke ; Edwardsite, Eremite, Shepard. Monoclinohedric, C = 77, ooP 94 35' ; usual combination OP . ooP - ( ooPoo ) . Poo . Poo , in which OP : Poo = 129 6', OP : Poo Family.] SAMARSKITE. 285 Fig. 161. = 139 25' (fig. 161). Crystals thick, tabular, or very short prismatic ; singly imbedded. Cleavage basal im- perfect. H. = 5 5-5 ; G. = 5 5-25. Translucent on the edges ; lustre dull resinous ; colour flesh-red, hyacinth-red, and reddish-brown. B.B. infusible ; moistened with sulphuric acid, colours the flame green. Soluble in hydrochloric acid. Analyses. Phos- phoric acid. Ce- rium prot. Lan- TVl than ? ho " oxfde.| nna - Tin oxide. Mang. perox. Lime. Mag- nesia. Total. 1 28-50 2 28-05 3 17-94 26-OOa 37-36 40-35 23-40 1 17-95 27-411 ... 21-30 | ... 2-10 1-75 1-86 1-68 1-46 1-50 ...& 0-80c ...d 101-49 96-83 97-72 Kersten, Ural. Hermann, Do. Do. Do. (a) Peroxide; (6) + traces of potash and titanic acid ; (c) + traces of manganese andiron; (d) + 6-27 substance like tantalium, 1-36 water, with traces of magnesia and iron peroxide. Hermann's analysis chiefly differs from Kersten's in that he finds no thorina, which, however, both Wohler and Berzelius affirm occurs in this mineral, and that he considers the cerium as the protoxide. The loss arose from the pounded mineral having been ignited in the open ah*, when it lost moisture and absorbed oxygen. The monazite is found in a granitic rock in the Ilmen mountains ; the edwardsite, identified with it by G. Rose, along with sillimanite, at Norwich and Chester in Connecticut, and at Yorktown in New York. Shepard states that it contains thorina and lanthanium oxide, and regards the zirconia in his former analysis as arising in a mixture of zircon. No. 3 is the Monazitoid of Hermann, found with monazite, passing into it and crystallizing in the same forms, G. = 5*281, but distinguished by its brown colour. It is only partially soluble in acids, and B. B. incandesces strongly, but does not fuse. 198. SAMAKSKITE, H. Rose ; Uranotantalite, G. Rose ; Yttroilmenite, Hermann. Rhombic ; isomorphous with columbite (Hermann ?) mostly imbedded inflat, somewhat polygonal grains. Fracture conchoidal ; brittle. H.= 5-5 ; G. = 5'625 ; opaque ; strong semi-metallic lustre ; velvet-black ; streak dark reddish-brown. B.B. fuses on the edges to a black glass. Powder easily fused with borax in the inner flame to a yellow, in the outer to a yellowish-green glass, inclining to red when more of the flux is added. In the closed tube decrepitates, yields water, incan- desces, and becomes brown. Soluble in hydrochloric acid with diffi- culty, but wholly to a greenish fluid. Analyses, next page. Occurs in grains the size of a hazel nut or under in the miascite of the Ilmen mountains near Miask. It does not contain the tantalio 286 CALC-SPAR. [Calc-spar Me- tallic acid. Mag- nesia. Lime & mang. protox. Iron prot. Ura- nium aerox. Yttria 1 Titan, acid. rium prot.c Total.. ; 5638 56-00 55-91 57-81 0-80 075 0-75 0-50a 0-92 1-02 1-88 0-31 15-43 1590 1591 13-61 14-16 1670 16-77 1-876 9-15 11-04 8-36 18-30 5 : 90 2-27 96-84 j v. Perez. 101 -41 ! Do. 99-61 ! Do. 100-581 Hermann. (a) Lime; (&) protoxide ; (c) with lanthanium oxide. acid of the Finnland minerals, but niobic and tungstic acids, some- times with a trace of pelopium, and hence the original name was changed by H. Rose. In No. 1 some uranium was lost. Hermann once thought that No. 4 contained the acid of a new metal, which he named ilmenium, but the researches of H. Rose have shown that this is niobic, mixed with tungstic acid, and the mineral identical with samarskite. Hermann found a lower specific gravity, but this arose from employing the ignited mineral ; as H. Rose observed a specimen of yttroilmenite to fall from Gr. = 5 - 703 before, to 5-454 in powder after ignition, and another of samarskite from 5'617 before, to 5*37 5*485 after, also in powder. II. ORDER. SALINE STONES. I. FAMILY. CALC-SPAR. 199. CALC-SPAR ; Calcareous spar ; Carbonate of lime, Phillips, Jameson, fyc. ; Kalkspath, Kohlensaurer Kalk, Werner, fyc. ; Chaux carbonatee, Hauy ; Rhombohedral Lime Haloid, Mohs. Rhombohedral, R 105 3' to 105 18', the most common variety being 105 8'. The forms and combinations are exceedingly nume- rous. Among the more remarkable are the following, principally after Naumann. More than thirty rhombohedrons, among which especially R 135, R, |R 95, 2R 79, and 4R 66 prevail, along with OR and ooR as very common limiting forms. More than fifty distinct scalenohedrons, the most frequent being R 3 , R 2 , and ^R 3 . The se- cond hexagonal prism ooP2 is also common, whilst hexagonal pyra- mids are among the rarer forms. Some of the most usual combina- tions are o>R . R, like the simple form fig. 163 below ; or R . Family.} CALC-SPAR. 287 ooR, very frequent ; also cR . OR, or OR . ooR ; and likewise 2R . R ; R 3 . ooR ; R 3 . ooR . 2R ; R 3 . R 3 ; and many others, upwards of an hundred distinct combinations being known. Fig. 162 represents a more complex combination, or R 5 (y) . R 3 (r) . R (P) . 4R (m) . ooR (c). The faces of the crystals are generally straight, but sometimes curved ; OR being frequently drusy or rough ; R striated parallel to the clinodiagonal of its faces ; whilst the scaleno- hedrons (R n ), and R, and 4R appear. The rhombohedrons often have the faces more or less curved, and saddle-shaped ; more rarely they are lenticular or spheroi- dal. The crystals sometimes imbedded singly, generally combined in druses ; also in coarse or fine granular or compact masses, often eel- Family. ,] DOLOMITE. 291 lular and porous. Cleavage, rhombohedral along R ; the planes often curved. H. = 3-5 4-5 ; G. = 2 85 2'95. Translucent ; lustre vitreous, but often pearly or resinous; colourless or white, but fre- quently pale-red, yellow, or green. B.B. infusible, but becomes caus- tic, and often shows traces of iron and manganese. Fragments effer- vesce very slightly or not at all in hydrochloric acid ; the powder is partially soluble, or wholly when heated. According to v. Zehmen, the very fine powder ignited on platina-foil for a few minutes over a spirit-lamp continues pulverulent, but intumesces slightly during ig- nition. Chem. com. generally c a c' + Mg c, with 54*3 carbonate of lime and 45'7 carbonate of magnesia ; but other varieties give diffe- rent or even indeterminate proportions. Analyses. Carb. of lime Carb. ofmag. Carb. of iron pro. Carb. of man.prot. Total. 1 73 25 ...a 100-25 Klaproth, Taberg. 2 70-5 29-5 100 Do. Gurhof. 3 61-00 38-53 2-74 100-27 Rammelsberg, Kolozoruk. 4 5666 3860 3-3U 170 100-26 Meitzendorf, Zillerthal. 5 51-00 44-32 468 100 Pelletier, Traversella (?) (G. = 2'629.) 6 85.84 10-39 5-53 101-76 Kiihn, Kolozoruk, near Bilin. 7 61-30 8 77-63 32-20 18.77 6-27 3-67 ... 99-77 100-07 Do. Bohemia, upper layer. Do. Do. lower layer. 9 28-0 67-1 3'5 * 99-0 John, Meisner (Conite). 10 54-76 42-10 4-19 101-05 Kiihn (Tharandite). 11 55-62 42-40 0-56 98-58 Rammelsberg ? IJfeld (Rauhkalk). 12 75-87 24 '52 ... 100-39 Do. ? Rappenau, Silesia, granular limestone. 13 55-88 40-47 281 . 99-16 Scheerer, Gulbrandsdal, Norway. 14 55-36 15 46-40 41-30 26-95 25-40 ...& ...c 99-16 99-50 Laugier, La Spezzia. Schweitzer, Tinzen in Graubiindten. (a) + 2-25 iron peroxide ; (6) + 2'00 iron peroxide and 0'50 silica ; (c) + 0-75 remainder Nos. 1-10 are crystallized, 11-14 massive dolomites or magnesiaii limestones. The proportion of carbonate of lime to carbonate of mag- nesia is in Nos. 4, 10, 11, 13, 14 nearly as 1 : 1 ; in Nos. 3, 7 as 3 : 2 ; in Nos. 1, 2 as 2 : 1 ; in Nos. 8, 12 as 3 : 1 ; in No. 6 as 4 : 1 ; and in No. 9 as 1 : 3 ; but the proportions are not exact, and more pro- bably indefinite. No. 15, of a white colour, is remarkable for the amount of iron, and is rather an ankerite. In a crimson red variety from Przibram in Bohemia, G. = 2-921, Gibbs found, on a mean of two trials nearly agreeing, 31'79 lime, 17-00 magnesia, 4-70 oxide of cobalt, 1-26 protoxide of iron, and 45'25 carbonic acid (= 100). This, according to Rammelsberg, gives ca c + (Mg, co, Fe) c, and is the first instance of cobalt being found in this mineral, and the metal is in the state of a neutral carbonate, in which it is not known independently. The diversity of its forms and composition, and its external resem- blance in many cases to other species, has created considerable con- fusion in reference to this mineral, which has been increased by the 292 DOLOMITE. [Calc-spar several varieties being often limited to certain localities. The massive, granular, sometimes easily divisible variety, of a white colour, has been named dolomite ; a similar variety, but larger grained, or dis- tinctly crystallized and cleava-ble, often with colours inclining to green, is the rhomb or bitter-spar, the Rautenspath and Bitterspath of the Germans ; and a third, either in simple crystals or in imitative forms, of colours inclining to red or brown, and more distinct pearly lustre, is the brown-spar and pearl-spar of mineralogists. Many so-called brown-spars are, however, arragonite, other foliated, rose-red va- rieties, manganese-spar (diallogite), and others calc-spar. In ge- neral these minerals are most conveniently distinguished by the spe- cific gravity. Dolomite, or the massive varieties forming whole mountains, occurs especially in the Alps near St Gotthardt, on the Brenner in Tyrol, in Carinthia, near Baden in lower Austria, and in the Apennines. Crystallized specimens are common in Salzburg, Tyrol, and Swit- zerland. Rhombohedrons of considerable size, sometimes macled, are found with transparent quarz at Traversella in Piemont ; and fine transparent specimens also at St Gotthardt and at Gap in France. Pearl- spar, in fine varieties, in the lead mines of Alston in Cumber- land, in Derbyshire, and at Leadhills and Charlestown in Scotland. In North America, Roxbury in Vermont, Lockport near Niagara, and Rochester New York, furnish this mineral. A greenish macled variety is found at Mieino in Tuscany (Miemite), at Gliicksbrun in Thuringia, and Tharand in Saxony (Tharandite). Rhombohedrons with convex faces occur in basalt at Kolosoruk near Bilin, in Bo- hemia, and a remarkable massive variety of oil-green colour and double granular structure at Rakovitza in Syrmia. The Gurhofian (No. 2), from Gurhof in lower Austria, is white and compact like semiopal. The compact varieties or magnesian limestones are valued for mortar, being considered more durable than limestone. They often prove injurious when applied too soon after calcination to land. This rock is also valued as a building stone, the cathedral of Milan, York Minster, and the New Houses of Parliament being constructed of it. The Parian marble has been supposed to belong to this species from its specific gravity, and also the lona marble in the Hebrides. Many geologists consider that dolomite has been produced by a meta- morphic action of volcanic gases on common limestone; and the calcareous blocks ejected from Vesuvius are very similar in character. Other geologists have assigned a direct igneous origin to some masses of this rock ; whilst many magnesian limestones like those in the Family. .] BREUNNERITE MAGNESITE . 293 north of England are probably original deposits. The flexible lime- stone from near Sunderland is a magnesian rock. The Predazzite of Petzholdt, which forms whole mountain masses at Predazzo in Tyrol, has a coarse or fine granular structure, a white colour, and vitreous lustre on the cleavage planes ; H. = 3*5 ; G. = 2*623. Leonard! found 6'98 per cent, water, and in the remainder 68*7 carbonate of lime, 30*3 carbonate of magnesia, and TO silica, alu- mina, and iron peroxide (= 100). It is probably merely a dolomite, or, according to Damour, a limestone, or common carbonate of lime, mixed with 35 per cent, hydrate of magnesia and 1 per cent, silica and protoxide of iron. 201. BREUNNERITE, Haidinger, Phillips; Talkspath, Naumann; Giobertite, Beudant ; Brachytypous Lime-Haloid, Mohs. Rhombohedral ; R 107 10' 30' ; as yet only known in single imbedded crystals of the form R ; and in granular or columnar aggre- gates. Cleavage, along R very perfect, with straight faces ; H. = 4 4*5 ; G. = 2-9 3*1. Transparent or translucent on the edges. Lustre highly vitreous. Colourless, but often yellowish, brown, or blackish-grey. B.B. infusible, but generally becoming grey, or black and magnetic. With soda shows reaction for manganese. Soluble in acids, often only when pulverized and warmed. Chem. com. essentially carbonate of magnesia, M S c , with 51-7 carbonic acid, and 48'3 magnesia, but often mixed with carbonate of protoxide of iron or manganese. Analyses. 1 2 3 4 5 6 7 Carbo- nate of magnes. Carbon, iron prot. Carb. of manga, protox. Total. 8970 8778 86-05 84-79 84-36 82-91 82-89 8-02 10-54 13-15 13-82 10-02 15-59 1697 2-44a 0-90 P (M) . Poo (k), generally long prismatic ; ooPoo .

< ; but simple crystals are rare from the great tendency to form macles, conjoined by a face of ooP, and repeated with the planes of combination either parallel or inclined (figs. 166, 167). It occurs in crystals either imbedded singly, or united in druses ; also in columnar and fibrous aggregates, and in crusts, stalactites, and other forms. Cleav- age, brachydiagonal distinct, also prismatic along ccP, and brachydoma- tic along Poo imperfect. Fracture conchoidal or uneven ; H.= 3'5 4 ; G =2-9 3 (2-931 transparent crystals from Bohemia, massive varieties as low as 2-7). Transparent or translucent ; lustre vitreous ; colourless, but often coloured yellowish- white to wine-yellow, reddish- white to brick-red, also light-green, violet-blue, or grey. In the closed tube, before reaching a red heat, it swells and falls down into a white coarse powder, evolving a little water. A portion of this powder heated in the forceps, B. B., colours the flame carmine- red when strontia is present ; on charcoal it becomes caustic, and with fluxes acts like calc-spar. Chem. com. carbonate of lime c*a c, occasionally mixed with carbonate of strontia. Analyses. Carb. of Lime. Carb. of Strontia Water. Iron perox. Total. 2 97-10 97-98 2-46 1-09 0-41 0-26 99-97 99-33 Stromeyer, Kaiserstuhl (radiated). Do. Nertschinsk (columnar). 3 96-18 2-24 0-31 0'22a 98-75 Do. Eschwege (Do.) 4 5 98 '00 98-95 1-01 0-50 0-21 0-20 0-14a 0-14o 99-37 9979 Do. Aussig (fibrous). Do. Waltsch (Do.) 6 7 98-62 99-31 0-99 006 0-17 0-33 0-11 ...6 9989 99'89 Nentwich, Herrengrund (G.=2-93). Do. Retzbanya (G.=2'86). (a) Hydrated; (6) + 0-19 carbonate of copper. 296 ARRAGONITE. Kirwan first suspected the presence of strontia in this mineral, and Stromeyer found it in all the varieties he examined, and hence thought it the cause of the physical and geometrical differences between ar- ragonite and calc-spar. But Bucholz and Meissner discovered no strontia in arragonite from Neumark, Saalfield, Minden, Bastenne, and Limburg ; and Delesse also, none in that from Herrengrund. Repeated experiments have shown that carbonate of lime with no strontia, in certain circumstances, assumes the form of arragonite, in others of calc-spar. G. Rose has observed that a salt of lime, preci- pitated by an alkaline carbonate in the cold, appears under the mi- croscope rhombohedric like calc-spar ; precipitated at a boiling heat, prismatic like arragonite. Mitscherlich had previously remarked the partial conversion of arragonite crystals into calcareous spar from volcanic action. Breithaupt has also observed, in a mine at Stenn near Zwickau, which had lain forty years under water, a deposit of calc- sinter, formed of alternate layers of calc-spar and arragonite, in one mass repeated thirteen times. After heavy rains or snow much water passed through the mine, and the alternate deposition probably arose from the different temperature during summer and winter floods. This mineral never occurs forming rocks or entering into them as an essential constituent. It was first found in large macled crystals in gypsum at Molina and Valencia in Arragon in Spain. It is very common in amygdaloidal cavities and fissures in basalt and basaltic tufas, as at Bilin, Waltsch, and other parts of Bohemia ; and in mi- neral veins or beds as at Leogang in Salzburg, Herrengrund in Hun- gary, and other places. Thejlosferri or coralloid variety is common in the iron mines of Styria, and also in some limestone beds. The Satin spar, or fine fibrous silky variety, occurs at Dufton ; in stalac- titic masses in Galloway, Buckinghamshire, and Devonshire ; and of beautiful snowy whiteness at Leadhills in Lanarkshire. It is also found in serpentine in Pieniont, and in lava on Vesuvius, and in Iceland ; and is deposited as tufa by the Carlsbad and other hot springs. Arragonite is most readily distinguished from calc-spar by falling to pieces at a low temperature, which does not affect the latter, and also by its prismatic cleavage. The Tarnowitzite, from Tarnowitz in Upper Silesia, contains car- bonate of lead, in such abundance as to be shown by the blowpipe, proving its isomorphism with the carbonate of lime. Bottger found in it 95-94 carbonate of lime, 3*86 carbonate of lead, and O16 water (= 99*97). Kersten only 2'19 per cent, carbonate of lead. Family.] FLUOR SPAR. n. FAMILY. FLUOR SPAR. 205. FLUOR SPAR, Phillips ; Octahedral Fluor, Jameson ; Fluate of Lime, Phillips; Fluss, Werner; Flusspath ; Chaux Fluatee, Hauy ; Octahedral Fluor-Haloid, Mohs. Tesseral ; the most common form is the cube ccOoo , then the octahedron O, and the rhombic dodecahedron ooO (see figs. 1, 2, 3, p. 8). Many other forms occur in combinations, particularly various tetrakishexahedrons ooOw ; the ikositetrahedrons 2O2 and 3O3 ; and several hexakisoctahedrons, especially 4O2 (figs. 4, 6, 7, above). The crystals, often large and very regularly formed, are attached singly or collected in druses. Macles are common. Also found in coarse granular or columnar masses, or compact and earthy. Cleavage oc- tahedral perfect ; and hence the conchoidal fracture is rarely per- ceptible. Brittle ; H. = 4 ; G. = 3*1 3*2. Pellucid in all degrees ; lustre vitreous ; colourless, but generally coloured of very various, and beautiful shades of yellow, green, blue, and red ; the more common being violet-blue, wine or honey -yellow, and leek or emerald- green ; often two or more colours in one specimen. Many varieties phosphoresce when heated. B.B. decrepitates, often violently, phosphoresces and fuses in thin splinters to an opaque mass ; which, according to v. Kobell, in a stronger heat becomes infusible and alkaline, and colours the flame red, almost like strontia. Easily fusible with borax, salt of phospho- rus, or a little soda. With gypsum or heavy spar forms a transpa- rent bead, becoming opaque when cold. Slowly soluble in hydro- chloric or nitric acids ; readily in sulphuric acid with evolution of hydrofluoric acid. Chem. com. Ca F, or neutral fluoride of calcium, containing 48*14 fluorine, and 51*86 calcium (= 72*45 lime). In a compact grey variety from Gersdorf, Saxony, Klaproth found 67*75 (corrected 69*37) per cent, lime ; Davy, in a specimen from Derby- shire, 72*683 per cent. ; and Berzelius in that from Alston Moor 72*137, in that from Norberg, Sweden, 71*77 per cent. lime. In the Derbyshire variety Berzelius also found 0*5 per cent, phosphate of lime ; and Kersten affirms that several blue varieties from Marien- berg and Freiberg contain minute quantities of hydrochloric acid. Schaffhautl finds in the violet-blue fluor spar from Welserdorf in the Upper Palatinate, 0*02073 per cent, nitrogen, 0*00584 hydrogen, 0*0365 carbon, and 0'08692 chlorous acid (! !). Rammelsberg. Fluor spar occurs chiefly in veins, very rarely in beds as with magnetic iron or other ores, and never as a constituent of mountain rocks. It is a very common mineral in some countries, as in Eng- land, Saxony, and parts of the Harz ; in other countries it is very 298 TTTROCERITE. [Fluor Spar rare, as in Scotland, Ireland, Hungary, and Siebenburg. The lead mines of Alston Moor and Derbyshire furnish fine blue and green crystals, generally cubes, sometimes six or seven inches in the side. Octahedrons occur at Beeralston in Devonshire, and very many other forms in Cornwall. Octahedrons of an apple-green colour, are also found at Moldawa in the Banuat ; of rose- red near Mont Blanc, and of emerald-green in North America. In Saxony cubes are more common of violet-blue, or wine-yellow colours ; and the same form, sometimes above a foot in dimensions, has been found in primitive limestone in Jefferson County, New York, where it is usually green. Dark-blue cubes occur in greenstone near Gourock in Scotland, and fluor spar has also been found in granite at Monaltrie in Aberdeen- shire, on the Avon in Banffshire, and in Sutherland. Compactvarieties are common in Sweden, Cornwall, and near Stolberg in the Harz, forming large veins. Near Castleton in Derbyshire it occurs in large crystalline masses either with concentric colours or of a rich trans- lucent blue {Blue John), and is wrought into various ornamental articles. Fluor spar is also used for etching on glass, for which it was first employed by Henry Schwanhard of Nurnberg in 1670 ; and more extensively as a flux in reducing metallic ores, especially iron and copper. Its name is derived from the latter employment. The Chlorophane is a variety exhibiting a bright green phospho- rescent light when heated, and is found chiefly near Nertschinsk in Siberia, and also at Alston Moor in England. 206. YTTROCERITE, Berzelius, Phillips, Beudant ; Yttria Fluate'e, Dufrenoy ; Pyramidal Cerium Baryte, MoJis. Very similar to fluor spar. Occurs in granular, crystalline masses, or in crusts. Cleavage, imperfect parallel to a tetragonal prism ; H. = 4 5 ; G. 3'4 3'5. Translucent or opaque ; weak vi- treous lustre ; violet-blue to grey or white. B.B. the variety from Finbo yields water in the closed tube ; the dark ones become white when heated. Infusible on charcoal alone, but with gypsum forms an opaque bead. That from Broddbo becomes first milk-white, then brick-red, but does not melt with gypsum; in other respects acts like the Fluocerite. Soluble in hydrochloric acid, and evolve fluorine when heated with sulphuric acid. Analyses. 1 2 3 Lime. Cerium perox. Yttria Hydro- fluoric acid. Alu- mina. Silica. Total. 47-63 50-00 34-7 18-22 16-45 13'3a 9-11 8-10 15-5 25-05 25-45 19-46 6-5c l6 : 6P, very imperfect ; fracture uneven or con- choidal ; H. = 5 5-5 ; G. = 2*9 3. Transparent or translucent ; lustre vitre- ous, on the fracture resinous ; colourless or white, inclining to grey, green, yellow, and red. In closed tube yields water. B.B. intumesces, and melts easily to a clear glass, co- louring the flame green ; easily fusible in borax ; the powder gelati- nizes in hydrochloric acid ; the evaporated solution mixed with alcohol burns with a green flame. Chem. com. perhaps c a 2 si + "B si + H = 38-3 silica, 21-5 boracic acid, 34*6 lime, and 5'6 water; the boracic acid is considered as acting as a base, butBerzelius prefers regarding it as an acid, when the formula becomes ca 'B + c a si + H. Analyses, next page. At Arendal massive datholite forms veins in the hornblende rock and gneiss near the magnetic iron, and contains druses of the crystallized variety alone, or with calc-spar. It also occurs on Utoe in Soder- manland ; and at Andreasberg in the veins of silver ore. In Scotland Family.'} BARYTES. 307 Silica. Boracic acid. Lime. Watr. Total. 1 36-5 24-0 35-5 4-0 100-00 Klaproth, Arendal. a 37-65 21-24 35-40 5-70 100-00 Rammelsberg, Do. 3 37-52 21-38 35-40 5-70 100-00 Do. Do. 4 37'36 21-26 35-67 5-71 100-00 Stromeyer, Andreasberg. 5 8 38-51 38-48 21-34 2031 35-59 35-64 4-60 5-57 100-04 100-00 Du Menil, Do. Rammelsberg, Do. 7 6 36-09 36-39 1934 18-34 35-22 34-27 8-64 10-23a 99-28 100-00 Do. Arendal (Botryolite). Do. Do. Do. (a) from loss + 077 alumina and peroxide Of iron. it is found in the trap rocks of Salisbury Craigs, and in Glen Farg in Perthshire. Fine crystals occur in amygdaloids in Connecticut and New Jersey in North America. Levy named some complex crystals Humboldtite. They are found at Sonthofen in Bavaria, in veins of calc-spar in sandstone ; and on the Seisser Alpe, and at Theiss near Clausen in the Tyrol, in agate nodules with prehnite and zeolites. It has also been met with in the ejected blocks on Vesuvius. The Botryolite of Hausmann (Nos. 7, 8) seems almost a variety of datholite. It occurs massive or fine fibrous, forming small botryoidal or reniform crusts of a snow-white or hair-brown colour, investing calc-spar crystals. It agrees in physical and chemical characters with datholite, and has the same composition, but with two atoms water. It has only been found at Arendal in the magnetic iron ore with calc-spar, quartz, schorl, and pyrites. III. FAMILY. HEAVY SPAR. 219. BARYTES ; Heavy spar, Sulphate of Barytes, Phillips, Sfc. ; Schwerspath, Baryt, Schwefelsaurer Baryt, Werner, fyc. ; Ba- ryte sulfatee, Hauy ; Prismatic Hal -Baryt, Mohs. Rhombic, ooP (#) 101 40', Poo (/) 74 35', Poo (d) 102 17'; these three forms, with OP (c), predominate in most of the very nu- merous combinations (figs. 172, 173, 174). The character of the crystals is either tabular from the predominance of OP, or columnar from prismatic forms, usually the domes Poo , or i Poo , and hence the prisms are generally to be placed horizontally. The crystals occur either singly, or more often united in druses or groups. It also occurs in foliated, columnar, fibrous, granular or compact masses. Cleavage, basal perfect, prismatic along ooP rather less perfect, brachydiagonal in traces only. H. = 3 3*5 ; G. = 4'3 4'7. Transparent to 308 BARYTES. [Heavy Spar translucent ; lustre vitreous or resinous ; colourless and white, but generally coloured reddish-white, or flesh-red, yellow, grey, bluish, Fig. 172. Fig. 173. greenish, or brown. B.B. decrepitates violently, and fuses very diffi- cultly, or only on the edges, at the same time colouring the flame yellowish-green. In the reducing flame it forms sulphuret of barium, which, when dissolved in hydrochloric acid, evaporated, and mixed with alcohol, does not cause it to burn with a red colour. Not so- luble in acids. Chem com. Ba's' with 34-3 sulphuric acid, and 65' 7 baryta. Analyses. Sulnh. baryta. Sulph. of strontia. Silica. Watr. Iron. Total. 1 2 3 4 5 6 7 J)7'50 90 99 99-38 86-00 99-4 83-48 0-85 675 0-6c 15-12 0-8 10 575 o'tfW 07 0-07 a 0-37 0-25e trace. 0(56 99-35 100 99 99-50 98-87 100 99-74 Klaproth, Frieberg (foliated). Do. Peggau, Styria (granular). Do. New Leiningen (fibrous). Stromeyer, Nutfield, Surrey. Jordan, Klausthal (compact). Rammelsberg, Silbach. Do. Gorzing, Anhalt-Kothen. (a) With colouring matter; (b) hydrated peroxide; (c) sulphate of baryta, with traces of strontia ; (d) lime ; (e) earthy matter. No. 6 was a colourless crystal, with G. = 4-4864 ; No. 7 a brown- ish-yellow crystal from a pit of brown coal, with Gr. = 4 488. In a specimen from Nutfield (No. 4), Stromeyer formely found 33-87 sul- phate of baryta, and 65-81 sulphate of strontia. This is a very common mineral in rocks of all ages, though never forming one of their essential constituents. It occurs chiefly in veins, either alone as in porphyry, or accompanying ores. Its crystal forms are very numerous, Hauy describing 73, and Levy 42 combinations. Tabular crystals of a large size are found at Dufton, one weighing 42 Ibs. ; smaller ones in Bohemia, and of splendid colours at Felso- banya and Kremnitz in Hungary. Prismatic forms are common in Auvergne. Fine varieties also occur in many parts of the United Family.'] DREELITE WITHERITE. States. Columnar heavy-spar, the Stangenspath of Werner, in in- distinct prismatic pearly crystals, is very common at Freiberg. Thfe Bolognese stone is a radiated variety from near Bologna, which, after being heated and placed in the sun's rays, phosphoresces in the dark. The Cawk from Derbyshire and Staffordshire is a massive variety. Veins of this mineral are common in the felspar rocks of Scotland, aa in the Braid Hills near Edinburgh, the Pentlands, and Cheviots. It is used as a white pigment, alone or with white-lead, and mined for this purpose in the granite of Arran. When mixed with ores it is considered prejudicial ; and it is also a violent poison. The Lime barytes from Freiberg, Strontian, and Derbyshire, seems merely a mixture of this mineral with sulphate of lime. Its crystals, chiefly tabular, and combined in rosettes and other groups, agree in form with barytes ( ooP = 101 53', Breit.). G. = 4'0 4'3. The Hepatite, of a more or less dark-grey colour, from the Kongs- berg mines in Norway, seems a mere mixture of barytes with carbo- naceous matter. The Allomorphite of Breithaupt, found in scaly masses at Unterwirbach near Rudolstadt, agrees in essential cha- racters and chemical composition (98'05 sulphate of baryta, 1*90 sul- phate of lime, Gerngross) with barytes. 220. DREELITE, Dufrenoy. Rhombohedric ; R 93. The crystals occur attached to sandstone. Cleavage, rhombohedric along R imperfect ; H. = 3 4 ; G-. = 3 '2 3*4. Lustre, externally dull, on the cleavage faces pearly. Colour white. B.B. fuses to a white vesicular glass. Effervesces with hydrochloric acid, but only partially dissolves. Chem. com. c a s" + 3 Ba "s" according to Dufrenoy, who found on analysis, 61*73 sul- phate of baryta, 14-27 sulphate of lime, 8'05 carbonate of lime, 9'71 silica, 2-40 alumina, 1'52 lime, 2*31 water (= 100). It was found in the old lead mine of Nuissiere near Beaujeu in the Rhone depart- ment in France. 221. WITHERITE, Werner, Phillips ; Carbonate of Barytes, Baryte carbonatee, Hauy ; Diprismatic Hal-Baryt, Mohs. Rhombic ; c*P 118 30', 2Poo 68. In generalform the crystals ap- pear hexagonal, and with the macles resemble those of arragonite, but Fig. 175. ar e rather rare. Two of the more common combinations are ooP . . 2Poo (fig. 175), and this form with P. It is more common in spherical, botryoidal, or reniform masses, with a drusy surface, and radiated, columnar texture. Cleavage, ooP distinct, 2Pco and coPoo im- perfect. Fracture uneven ; H. = 3 3'5 ; G. = 4*2 4'3. Semitransparent or translucent, but the crys- 810 ALSTONITE BARYTO-CALCiTE. [Heavy Spar tals often covered by a dull, opaque crust. Lustre vitreous, or resinous on the fractured surface. Colourless, but generally yellowish or greyish. B.J3. fuses easily to a transparent globule, becoming opaque when cold. On charcoal after some time boils, becomes caustic, and sinks into the support. Soluble with effervescence in nitric or hydrochloric acids when not too much concentrated. Chem. com. Ba c , or 22*3 carbonic acid and 77'7 baryta; with which the analyses of Klaproth of a variety from Anglesark (22 carbonic >acid, 78 baryta), and of Withering (21 '4 carbonic acid, 78'6 baryta), closely agree. It is found abundantly in various parts of England, as in the lead mines of Alston Moor in Cumberland, in Northumber- land, and in Lancashire, where it is used for poisoning rats ; and in less amount at Peggau in Styria, Leogang in Salzburg, in Hungary, Sicily, Siberia, and Chili. The sulphato-carbonate of barytes described by Thomson, from a single specimen found at Brownley hill in Cumberland, is probably an accidental mixture. It contained 64-8 carbonate of baryta, and 34-3 sulphate of baryta, and formed broad hexagonal prisms, ending in an obtuse six-sided pyramid. 222. ALSTONITE, Breithaupt; Baryto-calcite, Johnston. Rhombic, ooP 118, Poo 108, usual combination P . 2P . 6 92-15 050 1'87/ 1-83 1-00 97-35 Brandes, Fassa Valley. 7 54-73 43-76 ..* l-42e 99-91 Madrell, Dornburg. 8 35-72 40-20 0-59a 2306 072 100-29 Thomson, Kingston. (a) Protoxide ; (6) + 0'05 alumina ; (c) hydrated ; (d) + 0'31 lime ; (e) lime; (/) sulphate. Nos. 1, 2 7 fibrous ; No. 3, foliated ; No. 4, decomposed ; and No. 5, radiated celestine. mon in the newer formations. The sulphur mines of Girgenti and other parts of Sicily furnish fine crystals. Large blue crystals come from Strontian island in Lake Erie ; and smaller ones from Herrengrund in Hungary, Bex in Switzerland, Aust Ferry near Bristol, the Calton Hill, Edinburgh, and many parts of North America. It is found in amygdaloidal rocks at Monte Viale near Verona, and at Tantallan in East Lothian in Scotland. It is also found in fissures in the chalk and flint of Meudon near Paris ; and in earthy nodules at Montmartre. It is very rare in mineral veins, as near Meissen. The Bary to -celestine of Thomson occurs in radiating columnar or foliated masses, of a bluish-white colour, very brittle and friable. H. = 2-5 ; G. = 3-92. B.B. difficultly fusible. Chem. com. nearly 2 Sr s" + Ba s", by analysis No- 8. It is found on Drummond Island in Lake Erie, and at Kingstown in Upper Canada. A celestine from Norten in Hanover, in which Gru'ner found 26, and Turner 20-4 per cent, of sulphate of baryta, seems a similar variety. 225. STRONTIANITE, Jameson; Stronthian, Werner; Strontites, Allan; Carbonate of Strontian, Phillips; Strontiane carbonatee, Hauy ; Peritomous Hal-Baryt, Mohs. Rhombic; ooP 117 19', 00 108 12'; the crystals and macles Fig. 178. similar to those of arragonite (fig. 178). Often acicular, pointed and in diverg- ing groups. It also occurs in broad col- umnar and fibrous masses. Cleavage, prismatic along ooP (-M), and brachy- domatic along 2Poo (P) (69 16') im- perfect ; H. =3-5; G. =3-6 3-8. Translucent or transparent ; lustre vitreous, or resinous on the frac- tured surfaces ; colourless, but often coloured light asparagus or apple-green, and more rarely greyish or yellowish. Streak white. Family.'] GYPSUM. 313 B.B. fuses in a strong heat only on very thin edges ; intumesces in cauliflower-like forms, shines brightly, and colours the flame red. Easily soluble with effervescence in acids. The solution in hydro- chloric acid, evaporated and then dissolved in alcohol, makes this burn with a carmine-red flame. Chem. com. s'r c with 30 carbonic acid and 70 strontia, but often contains carbonate of lime. Analyses. Strontia Carb. acid. Lime. Man*, perox. Watr. Total. 1 65-60 2 67-52 3 92-876 4 92-756 5 93-496 6 91-086 30-31 29-95 3-47 1-28 6-506 6-506 6-286 8-646 0-07a 0-09 ...c 0-08 0-07 0-25 025 99-53 9891 9962 99-86 9977 99-72 Stromeyer, Strontian. Do. Braunsdorf, Freiberg. Jordan, Clausthal 'white). Do. Do. (yellow). Thomson, Strontian (green). Do. Do. (brown). (a) With iron peroxide ; (6) carbonate of; (c) + 0'36 carbonate of iron protoxide. Strontianite was first found at Strontian in Argyllshire, forming veins in gneiss with barytes and galena. Large crystals occur at Leogang in Salzburg, but are rare. It is also found in Yorkshire in acute snow- white pyramids, at the Giant's Causeway in Ireland, at Braunsdorf in Saxony in hexagonal or acicular prisms, at Hamm in Westphalia, the Harz, at Schoharie and other parts of the United States, and it is said at Popayan, Peru. The Emmonite is a mere variety from North America, in which Thomson found 12'5 per cent, carbonate of lime. It is used to produce red fire in pyrotechnic exhibitions. The Stromnite or Barystrontianite of Traill from Stromness in Ork- ney, occurs in yellowish- white, semitranslucent masses, with a faint pearly lustre, and crystalline structure ; H. = 3 '5 ; G. = 3*7. It contains 68*6 carbonate of strontia, 27'5 sulphate of baryta, 2'6 car- bonate of lime, and O'l oxide of iron (== 98-8), Traill; but is per- haps only a mixture of strontianite and barytes. IV. FAMILY. GYPSUM. 226. GYPSUM, Jameson ; Sulphate of Lime, Phillips, Sfc. ; Gyps, Fraueneis, Werner ; Chaux Sulfatee, Hauy ; Gypse, Beudant ; Prismatoidal Euclase Haloid, Mohs. Monoclinohedric ; C. = 81 26'; the most common forms are ooP 111 14', P 138 44', P 143 28', and (ooPoo) ; several clino- prisms ( ooPwz) also occur. Two common combinations are ooP ("/) . ( ooPoo ) (P) . P (/) (fig 179), and this with P ; they appeal- partly short and thick, partly long and thin prismatic, partly also tabular. GYPSUM. [Gypsum Lenticular crystals often occur, formed essentially of P . P< Fig. 179. OP . oo P, with the faces more or less curved. Macles are frequent, either with the twin axis the chief axis (fig. 83 above), especially in prismatic crystals ; or with the twin axis the normal of Poo , the lenticular crystals especially being con- joined by this law. The crystals are either im- bedded singly or united in groups and druses. It is also found massive, in very coarse to very fine granular or compact aggregates ; in fibrous crusts and veins ; and in scaly or pulverulent masses. Cleavage, clinodiagonal very perfect, hemipyra- midal along P, much less perfect ; these two cleav- ages generally alternate, so that the planes, espe- cially the latter, appear fibrous or striated ; also orthodiagonal, but imperfect, and passing into the flat conchoidal fracture. Sectile, thin plates flexible (but not in all varieties) ; H. = 1-5 2 (lowest on P) ; G. =. 2-2 2-4. Transparent or translucent. Lustre vitreous, on the more perfect cleavage planes pearly, on the pyramidal silky. Colourless and snow-white, but often coloured red, grey, yellow, brown, and more rarely greenish or bluish. In the closed tube yields water B.B. becomes opaque and white ; exfoliates and fuses to a white enamel, which is alkaline. On char- coal in the inner flame forms an hepatic mass. With fluor spar melts to a clear globule, becoming white and opaque when cold. It is soluble in 400 to 500 parts of water, which then shows traces of lime and sulphuric acid. It is scarcely more soluble in acids. Wholly decomposed by boiling in a solution of carbonate of potash. Chem. com. neutral sulphate of lime with two atoms water, or c'a 's' + 2 H = 46-47 sulphuric acid, 32- 65 lime, and 20'88 water. The following varieties contained Sulphuric acid. Lime. Crystals, 44-8 ... 33'0 Fibrous, 44-13 ... 33'00 Compact, 44-25 ... 3375 Water. 21-0 = 98'8 Bucholz. 21-00 = 98-13 Do. 21-00 = 99-00 G. Rose. Gypsum is a very common mineral, especially in the more recent sedimentary formations, and is even now forming either as a deposit from water holding it in solution, or from the decomposition of py- rites or sulphuret of iron, when the sulphuric acid combines with lime, or from the action of sulphurous vapours in volcanic regions on calcareous rocks. It is often imbedded in nests or reniform masses in clay or marl, more rarely makes part of mineral veins, but seldom, Family.] ANHYDRITE, 315 if ever, forms veins by itself. The transparent crystals are named selenite, and fine specimens occur in the salt mines of Bex in Switzer- land, in those of the Tyrol, Salzburg, and Bohemia, in the sulphur mines of Sicily, at Lockport in 'New York, and other places in North America, in the clay of Shotover Hill near Oxford, at Chatley near Bath, and many other localities. Fibrous gypsum occurs of remark- able beauty at Ilfeld in the Harz, in the compact gypsum of northern Germany, and at Matlock in Derbyshire. Compact white gypsum or alabaster is found in great beauty at Volterra in Tuscany, and also in the Harz. Massive or compact gypsum forms whole beds in the trias and permian red sandstones of many parts of Germany, France, Italy, and England, and is often associated with rock salt. In Nova Scotia it occurs with similar beds in the lower carboniferous for- mations. The finer varieties are cut into various ornamental articles, as vases, and the so-called Roman pearls, chiefly distinguished from the true pearl by their specific gravity. Plaster of Paris, used for casts and other works of art, is formed by calcining the mineral and grinding it down to a fine powder, which forms a paste that soon hardens by absorbing the water driven off by the heat. It, however, loses this property when exposed to a temperature above 300 Fahrenheit, when it becomes similar to anhydrite. Gypsum is also used for glazing porcelain, in the manufacture of glass, as mortar and as manure, especially as a top-dressing for meadows. 227. ANHYDRITE, Jameson, Phillips ; Muriazit, Werner ; Karste- nite, Hausmann ; Chaux anhydro-sulfatee, Hauy ; Prismatic Orthoclase Haloid, Mohs. Rhombic ; ooP 100 8', Poo 74 ; combinations, OP . ooPoo . ooPoo . ooP, also OP . coPoo . ooPco , with subordinate faces of P and 2P2. The crystals thick . tabular, but on the whole very rare. It is chiefly found in coarse to fine granular, or almost compact ag- gregates, or with a columnar structure. Macles are rare. Cleavage, macrodiagonal and brachydiagonal both very perfect, basal perfect. H. = 3 3'5 ; G. = 2-8 3. Transparent or translucent. Lustre vitreous ; on ooPco pearly. Colourless or white ; but often coloured bluish-white to violet-blue, reddish-white to flesh-red, or smoke-grey. Streak greyish-white. In closed tube gives no water. B.B. fuses difficultly to a white enamel. In charcoal in a strong reducing flame yields an hepatic mass. Fusible in borax to a clear glass, becoming yellow when cold. With fluor spar fuses readily to a clear globule, which becomes opaque when cold, and, on continuation of the heat, 316 POLYHALITE. intumesces and becomes infusible. Very slightly soluble in water or acids. Chem. com. c a 's', with 58'75 sulphuric acid and 41'25 lime. Analyses. Lime. Sulph. acid. Iron perox. Silica. Watr. Total. j 1 43-06 59-78 o-io 0-25 103-19 Klaproth, Sulz (blue). 2 3 4 40-67 41-41 41-70 55-80 56-78 58-01 0-25 0-03 0-23 0-26 0-09 2-91a 0-94 0-07 100 99-42 99-87 Stromeyer, Ilfeld (fibrous;. Do. Vulpino (coarse scaly). Do. Do. (fine scaly). (a) + 0-09 carbonic acid and 0'04 bitumen. Anhydrite occurs chiefly with rock salt and gypsum, or in the clays associated with these deposits. It is also found in some beds or veins with metallic sulphurets and other ores. The crystalline varieties, or muriacite, occur in fine specimens in the salt mines of Bex in Switzerland, Hall in the Tyrol, and Aussee in Styria. Blue varieties are found at Sulz on the Neckar, and Bleiberg in Carinthia ; compact or columnar masses at Ischel in Upper Austria, Berchtesgaden in Bavaria, Eisleben, and various parts of the Harz. The granular variety, or Vulpinite (Nos. 3, 4), from near Bergamo, is polished for ornamental purposes. The con- torted species, or Gekrosstein, is chiefly found in clay in the salt mines of Wieliczka and Bochnia in Galicia. The blue varieties are occasionally used for ornamental purposes, but lose their colour by exposure to the sun. Many varieties much resemble gypsum, but are distinguished by their higher hardness and specific gravity, and the three rectangular cleavages. On exposure it attracts moisture, and is converted into gypsum, the change extending through whole rocks. In such cases the surface is often covered by small crystals of the latter mineral. 228. POLYHALITE, Stromeyer, Phillips, Sfc. ; Prismatic Brithyn- Salt, Mohs. Rhombic, ooP = 115 ; usual combination ooPoo . ooP . OP, in long broad prisms ; mostly combined in parallel columnar or fibrous aggregates. Cleavage, prismatic along ooP imperfect. H. = 3'5; G. = 2-7 2-8. Translucent; pearly or resinous; colourless, but generally coloured pale flesh or brick-red, seldom grey. Weak bit- ter, and slightly saline taste. Soluble in water, leaving gypsum. B.B. fuses on charcoal to an opaque reddish bead, becoming white when cold. Chem. com. 2 da "s" -f Mg "s* + K 's' + 2 H, the name (many-salts) being derived from the number of its constituents. Analyses, next page. Family.] GLAUBERITE. 317 Sulph. lime. Sulph. magnes. Sulph. potassa. Chloride sodium. Iron perox. Water. Total. 1 4474 2 45-43 20-03 20-59 2770 28-10 0-19 0-11 0-34 0-33 5-95 5 24 a 98-94 100 Stromeyer, Ischel. Rammelsberg, Aussee. (a) + 0-20 silica. Polyhallite occurs in the salt mines of Ischel in Austria, Aussee in Styria, and Berchtesgaden in Bavaria. No. 1 is the mean of several experiments, and No. 2 was a red variety. The similar grey and red minerals from Vic in Lorraine, analyzed by Berthier, were probably glauberite mixed with rock-salt, and the true polyhallite is not known from that locality. 229. GLAUBERITE, Brongniart, Phillips ; Brongniartin, von Leonhard; Hemi-prismatic Brithyn-salt, Mohs. Monoclinohedric, C = 68 16', ooP 83 20', P 116 20' (116 30', Duftenoy), OP : ooP = 104 15'. Usual combination OP . P, Fig. 180. sometimes with o>P (fig. 180). Crystals generally thick tabular, from predominance of OP. Cleavage, basal perfect, along ooP traces. H. = 2'5 3 ; G. = 2-75 2-85. Translucent ; lustre vitreous to resinous ; colourless, but yellowish or greyish-white. Taste slightly saline and bitter. B.B. decrepitates violently, and melts to a clear glass. On charcoal in the inner flame forms a hepatic mass. Decomposed by water, which removes the sul- phate of soda and leaves the sulphate of lime, and hence the crystals become opaque. In a large quantity of water it is almost entirely so- luble. Chem. com. N a 's* + ca *s", with 51 sulphate of soda and 49 sulphate of lime. Analyses. 1 2 3 Sulphate of soda. Sulphate of lime. Chloride of sodium. Clay, with iroYi. Total. 51 48-50 48-6 49 46-60 51-0 l'-20 270 : 100 9900 99-6 Brongniart, Villarubia. Dufrenoy, Vic, Lorraine. v. Kobell, Berchtesgaden. This rare salt occurs in salt and clay, especially at Villarubia near Ocana in Spain, at Vic, and Berchtesgaden. Also it is said in gyp- sum near Bragg in Aargau, and more doubtfully at Aussee and Ischel in Austria. In a variety from Tarapaca in Peru, Hayes found 67 '22 sulphuric acid, 21-32 soda, 20-68 lime, and 0-44 iron (= 99-66). Sir D. Brewster states that it has one axis of double refraction for violet, and two axes for red light. 318 PHARMACOLITE. [Gypsum 230. PHARMACOLITE, Hausmann, Phillips ; Arsenikbliithe, Werner, in part ; Chaux arseniatee, Hauy ; Hemiprismatic Euclase Haloid, Mohs. Monoclinohedric, C = 65 4', o>P 117 24', P 139 17' ; usual combination OP . ( ooPco ) . ccP . P. The crystals, prismatic and lengthened in the direction of the clinodiagonal, are small; often short acicular or capillary, and united in minute reniform groups or crusts, with a radiated fibrous texture. Cleavage, clinodiagonal very perfect. Sectile, and in thin laminae flexible. H. =2 2-5 ; G. = 2-6 2'8. Translucent ; lustre vitreous, on ( ooPoo ) pearly ; the fibrous masses silky. Colourless and white, but sometimes coloured rose-red or green. Yields water in the Closed tube ; B.B. fuses in the forceps in the outer flame to a white enamel ; in the inner flame on charcoal gives arsenic fumes, and fuses to a semitranslucent, sometimes bluish, grain, colouring the flame blue. Easily soluble in acids. Chem com. ca 2 AS" -f 6 H = 51 arsenic acid, 25 lime, and 24 water. Analyses. Arsenic acid. Lime. Mag- nesia. Cobalt oxide. Watr. Total. J 2 50-54 45-68 25-00 27-28 ... 24-46 23-8G 100 96-82 Klaproth, Wittichen. John, Andreasberg. a 79 -01 a ... 20-09 100 Turner, unknown. 4 51-58 23.59 1-43& 23-40 100 Rammelsberg, Glucksbrunn. 5 46-97 24.65 3-22 1-00 23-98 9982 Stromeyer, Riechelsdorf. (a) With lime ; (5) with peroxide of iron. This mineral much resembles the arsenious acid, but is distinguished by being insoluble in water. It is found with silver ores at Andreas- berg in the Harz ; at Glucksbrunn in Thuringia ; and Riechelsdorf and Biber in Hessia in cobalt veins in the kupferschiefer ; at Joa- chimsthal in Bohemia, and Markirchen in Alsace, in gneiss ; and at Wittichen in the Schwarzwald in veins in granite, along with arsenic and cobalt ores. It seems a recent formation, produced by the de- composition of ores of arsenic, the acid from which enters into union with lime. A singular proof of this is furnished by a specimen pos- sessed by Hausmann from Eiechelsdorf, in which the botryoidal concretions have formed on a human hair. In others from Joachims- thai, crystals of realgar are changed into pharmacolite. The Picropharmacolite of Stromeyer (No. 5) diifers chiefly in con- taining magnesia, and a rather smaller proportion of the arsenic acid, but can hardly be considered a distinct species. The Roselite of Levy, according to Haidinger, forms very small monoelinohedric macles (a prism = 47 12'), with a perfect cleavage in one direction. Lustre vitreous ; colour deep rose-red ; streak Family.'] HAIDINGERITE BERZELIITE ROCK SALT. 319 white. According to Children, it consists of arsenic acid, oxide of cobalt, lime, magnesia, and water. In the closed tube it yields water, and becomes black. B.B. with borax in the oxidating flame forms a deep blue glass. It is probably a distinct species, but still very im- perfectly known, only a few specimens having been found attached to compact quartz at Schneeberg in Saxony. 231. HAIDINGERITE, Turner. Jlhombic, ooP 100, P*> 127, P< 147, with cfcPoo and ooPoo , are the prevailing forms. The crystals are short prismatic, small, and united in drusy crusts. Cleavage, brachydiagqnal very perfect ; sectile, in thin plates flexible. H. = 2 25 ; G. = 2-8 29. Transparent or translucent; colourless and white. Che- mical characters and composition like pharmacolite, but with only 3 atoms water. Turner's analysis gave 85-68 arseniate of lime and 14-32 water. Only one specimen known, found with pharmacolite, probably at Joachimsthal in Bohemia. 232. BERZELIITE, Kiihn ; Magnesian Pharmacolite, Dana ; Chaux arse'niatee anhydre, Dufrenoy. Massive, with traces of cleavage in one direction. Brittle ; H. = 5'5 ; G. = 2-52. Translucent or only on the edges ; lustre resinous ; colour honey-yellow or yellowish-white. B.B. infusible, but becomes grey, and shows reaction for arsenic, and with soda for manganese. Soluble in nitric acid. Chem. com. ca 3 XV + Mg 3 AS but with part of the magnesia replaced by manganese protoxide. Analyses. E Arsenic acid. Lime. Mag- nesia. Mang. prot. Loss by heat Inso- luble. Total. 5851 66'46 23-22 20-96 1568 15-61 2-13 4-26 0-30 2-95 0-23 99-84 100-47 Ktihn. Do. It occurs at Longbanshytta in Sweden with hedyphane, which it much resembles. V. FAMILY. ROCK SALT. 233. ROCK SALT ; Chloride of Sodium ; Muriate of Soda, Phillips, -c. ; Steinsalz, Kochsalz, Werner, *c. ; Soude muriatee, Hauy ; Salmare, Beudant ; Selgemme, Dufrenoy ; Hexahe- dral Rock Salt, Mohs. Tesseral ; almost always ooOoo , rarely with faces of other forms. .Generally in granular and fibrous masses, the latter forming crusts 320 ROCK SALT. [Rock Salt or plates ; also disseminated. Cleavage, hexahedral very perfect. Fracture conchoidal ; rather brittle ; yields slightly when scratched with the nail ; H. = 2 ; G. = 2'1 2*2. Transparent or translu- cent ; lustre vitreous ; colourless or white, but often coloured red, yellow, grey, and rarely blue. Taste saline. In the closed tube de- crepitates, and yields a little water. B.B. on charcoal fuses and partly evaporates, partly sinks into the support. On platina wire with soda fuses to a clear mass, colouring the flame yellow. Added to a bead of salt of phosphorus with copper-oxide, colours the flame blue. Very soluble in water. Chem. com. Na Cl, with 60 chlorine and 40 sodium, but often with various impurities. In the Cheshire rock salt Henry found 98*32 chloride of sodium, 0*02 chloride of magnesium, 0'65 sulphate of lime, and O'Ol chloride of calcium, with TOO of insoluble matter. According to Mr W. Nicol, it also contains irregular cavities, full of a concentrated solution of chloride of magnesium, and a little chloride of calcium. Vogel, in the salt from Berchtesgaden and Hallein, found a little chloride of potassium ; in that from Hall and other salt springs chloride of ammonium. The red colour of rock salt is in general caused by peroxide of iron, but in that from Cardona arises, according to Marcel de Serres and Jolly, from enclosed infusoria. The decomposition of salt, by attracting moisture from the atmosphere, is caused by the mixture of chlorides of magnesium and calcium, as the rock salt which does not contain these substances, is not liable to deliquesce. Melloni found that polished plates of pure rock salt have a remarkable capa- city of transmitting radiated heat, 0'923 of the vertical rays passing through them unabsorbed. This important mineral is very widely disseminated, sometimes in thick beds or large masses, with clay, anhydrite, and gypsum in various formations, at other times as an efflorescence, covering ex- tensive tracts of country. The most celebrated European deposits occur at Wieliczka and other parts of Galicia, in Hungary, Sieben- burg, Moldavia, Styria, Salzburg (Hallein), in Tyrol (Hall), also in Bavaria, Wurtemberg, Switzerland (Bex), and Spain, especially at Cardona, where it forms a whole mountain. In England the chief deposits are in Cheshire, as at Northwich, where it occupies a basin- shaped hollow, and consists of orbicular masses with concentric coats, and is often so pure as to require no further preparation. As an efflorescence it is most abundant on the sandy plains on the Rio de S. Francisco, and Rio Paraguay in Brazil ; at the foot of the Atlas Mountains in Africa ; in Abyssinia, where the salt plain of Dalkali is said to extend for four days' journey ; in certain parts of Arabia, where it is used as a building material ; and in the Steppes round the Caspian Sea and Lake Aral. It is also found as a sublimation among Family.] ALUM. 321 the lavas of Vesuvius, and along with sulphur both in Switzerland and Sicily. Many springs and lakes contain salt in solution ; and in the water of the ocean it amounts to three or four per cent. Its various uses are too well known to require notice. (Compare, Kar- sten's Lehrbuche der Salinenkuude, Berlin, 1846.) A species of rock salt at Wieliczka decrepitates when dissolved in water. This arises from its containing vesicles full of compressed gases, which burst as the crust is dissolved. H. Rose found the gas to vary in amount, and also in composition, but in one case it con- sisted in 100 volumes of 24 hydrogen, 17 carbonic acid gas, and 59 carburretted hydrogen ; and Berzelius supposes some carbonic acid also to remain dissolved in the water. In other respects the mineral does not differ from common salt. The Martinsite of Karsten, found in boring for rock salt at Stassfurth in Prussian Saxony, also slightly decrepitates, and contains 90'98 chloride of sodium and 9'02 sulphate of magnesia, or in the proportion of 10 atoms of the former to one of the latter. Sylvin, or chloride of potassium, found according to Smithson as a sublimation on Vesuvius, and by Vogel in the rock salt of Hallein and Berchtesgaden, agrees in most characters with rock salt (G. = 1/9 2), and probably occurs with it in other places. It has also been found in sea water, and in iron furnaces either crystallized in cubes or compact. 234. ALUM, Phillips, $c. ; Alaun, Werner ; Alumine sulfate'e, Hauy ; Octahedral Alum-salt, Mohs. Tesseral; O, sometimes with ooOco and o>O. Generally occurs in crusts, with a parallel fibrous structure, or as an efflorescence. Macles rare, united by a face of O as in fig. 76 above. Cleavage, octahedral, imperfect. Fracture conchoidal. H. = 2 2-5; G. = 1-75 1-9. Translucent ; colourless and white. Taste sweetish astringent. Easily soluble in water. B.B. generally evolves sulphurous fumes, and the residue becomes blue with cobalt solution. Chem. com. ge- nerally R'S* + Ai's 3 + 24 H. There are several varieties, differing slightly in external and other characters, according as one isomorphic element is replaced by another. (a) Potash-alum (Kalialaun, v. Kobell ; Alun, Dufr&ioy), with R = K, and 33-52 sulphuric acid, 10-86 alumina, 9 -9ft potash, 'and 45 '66 water. In the closed tube it fuses, intumesces, and yields much water. It occurs in the alum slates of various formations, in deposits of brown coal, and near volcanic solfataras. Among its more remarkable localities may be mentioned the transition rocks of Sweden, Norway (at Christiana), and Scotland ; the coal formation, 322 ALUM, [Rock Salt as in the burning hill of Duttweiler near Saarbruck, and at Hurlet near Paisley, and Campsie, in Scotland ; in the lias near Whitby in Yorkshire ; in the brown-coals of Hessia and the Rhine ; in the vol- canic formations of the Lipari islands, Sicily, and the Azores. In many cases it is a recent produce of decomposing sulphurets, where alumina and potash are present. (ft) Ammonia-alum (Amoniakalaun, v. Kobell ; Alun ammoniacal, Dufrenoy), in which N H 3 's' replaces R "s", with about 4 per cent, am- monia and 48 water. In the closed tube it forms a sublimate of sulphate of ammonia ; and, heated with soda, yields ammoniacal odours. It occurs in thin layers in the brown coal of Tschermig in Bohemia. Analyses Nos. 1, 2, 3. (c) Soda-alum (Natrumalaun, v. Kobell ; Alun sodifere, Dufrenoy), with R = Na, and 7 soda and 48 water. It agrees in general with potash-alum, but is more easily soluble in water. It is found in St Juan near Mendoza in South America (No. 4), near the Solfatara at Naples, and in the island of Milo. No. 5 is another soda- alum, G. = 1-584, found in white or red fibrous masses in Southern Peru ; it is soluble in water, and corresponds to 2 Na's* 4- 3 A'I'S 2 + 10 H. (d) Magnesia-alum ( Talkerdealaun, v. Kobell ; Alun magnesien, Dufrenoy), in which R = M g , sometimes with MM. When newly ex- posed it is highly translucent and silky, but soon changes in the air. No. 6 is nearly a pure magnesia-alum, found about six inches thick covering the floor of a cave near Bosjesman's river in South Africa. No. 7 is the Pickeringite of Hayes, from Iquique in Peru, white, silky, and fibrous. No. 8, again, is a similar manganese-alum from Lagoa Bay in South Africa. (e) Iron-alum (Feather-alum ; Federalaun ; Alun de plume, Du - frenoy), with R = pe. To this belongs No. 9 from an unknown lo- cality, No. 10 from Hurlet near Paisley, and No. 11 from the quick- silver mines of Mbrsfeld in Rhenish Bavaria. No. 12, the Hversalt found on decomposing volcanic rocks at Krisuvig in Iceland, is re- markable for the alumina being partly replaced by iron peroxide. Some so-called rock-butter (Bergbutter) seem similar alums. (/) Voltaite, Sacchi, = 3 ( Fe , K, Na) "s + (pi, A!) 's' 3 + 12 H, occurs in octahedrons of a black colour, with greenish-grey streak, in the Solfatara of Pozzuoli ; and, according to Dufrenoy, also as a re- siduum of the distillation of sulphur. Though closely agreeing in external characters with the alums, it differs much from them in chem. com. (Nos. 13, 14), and should probably form a distinct spe- cies. It is also more difficultly soluble in water than alum. Analyses, next page. Family. J ALUNOGENE. 323 Sulph. acid. Alu- mina. Pot- ash. Soda. Am- mo- nia. Mag- nesia. Iron prot. Mang. prot. Watr. Total 1 36 00 12-14 ... 6-58 0-28 ... " 45-00 100 Pfaff. 2 38-58 12-34 ... ... 4-12 44-96 100 Lampadius. 3 36-06 11-60 3-72 : 12 48-39 99-89 Stromeyer. 4 37*85 12-04 ... 7 V 58 6 : 21 .. e 42-04 100 Thomson. 5 32-95 22-55 w 6-506 39-20 101-20 Do. 6 36-77 11-51 0.21 a 3 : 69 2 : 62 4574 100-09 Stromeyer. 7 36-32 12-13 ... 468 V 43c 45-45 99-74 Hayes. 8 32-79 10-65 1-086 7*33 48-15 100 Apjohn. 9 34-4 8-8 ... 0-8 12-0 44-0 100 Berthier. 10 30-9 5-2 20-7 43-2 100 Phillips. 11 36-03 12 35-16 10-91 11-22 0-43 ... 0-24 2-19 9-37 4-57 l-23d 43-02 45-63 100 100 Rammelsberg. Forchhammer. 13 45-67 3-27 5-4*7 ... 28-69 .../ 15-77 99-33 Dufre"noy. 14 48-32 2-20 4-04 0-25 ... ... 11-60 17'65'd 15-94 100 Abich. (a) Chloride of potassium; (6) sulphate; (c) with manganese protoxide + 0-13 lime and 0'60 hydrochloric acid; (d) peroxide; (e) -f- - 02 silica and 0-26 lime; (/) +0-46 remain- der. 235. ALUNOGENE, Beudant / Sulphate of Alumina, Phillips ; Alumine sulfate'e, Hauy ; Halotrichite, Glocker ; Haarsalz, Werner ; Hair salt, Feather alum, in part. Crystallization unknown ; occurs in capillary or acicular fibres forming crusts, botryoidal or reniform masses, or rarely in granular aggregates. H. = 1*5 2 ; G. = 1 4 6 1-7. Lustre silky ; colour white, inclin- ing to green or yellow. Tastes like alum. B.B. in closed tube in- tumesces, yields much water, and is infusible. With cobalt solution gives a pure blue, when it contains no iron. Easily soluble in water. When to the cold saturated solution a similar solution of sulphate of potash is added, crystals of alum are formed. Chem. com. L *s' 3 -f- 18 H, with 36-05 sulphuric acid, 15-40 alumina, 48-55 water. Analyses. Sulph. acid. Alu- mina. Watr. Iron prot- oxide. Mang. prot- oxide. Lime. Mag- nesia. Pot- ash. Silica. Total. 1 36-40 2 35-68 16-08 14-98 46-60 49-34 0-004 ... 0-002 0-004 ... 99-01 100 Boussingault. Do 3 29-0 15-0 51-8 l-2a ... (3-0)6 100 Mill. 4 40-31 14-98 40-94 0-85 0-26 l-13c 100 Hartwall. 5 36-97 14-63 44-64 2-58a . . ... 0-14 1-37 100-33 H. Rose. 6 35-82 7 37-38 15-57 14-87 48-61 45-16 246 o-i's ... 0-22 100 100-24 Rammelsberg. Do. 8 3571 12-78 47-02 0-67 1-02 0-64 0-27 0-32 98-43 Do. 9 35-64 11-23 48'85d 0-72 0-31 0-45 1-91 0-47 0-43 100 Do. 10 58-58 38-75 2-78P less so ; H. -= 2 ; G. = 1-8 1*9. Translucent, rarely transpa- rent ; lustre vitreous ; colour leek or mountain- green, often with a yellow coating on the sur- face ; streak white ; taste sweetish astringent ; very soluble in water. B. B. in closed tube melts in the water of crystallization, which then evaporates, and leaves a white anhydrous salt. Chem. com. Fe's'+ 7ik = 26*0 prot- oxide of iron, 28'8 sulphuric acid, and 45*2 water. This salt is a recent production from the decomposition of iron py- rites, and is manufactured by exposing this mineral to the atmosphere, 'and occasionally moistening it. Crystallized varieties have been found at Bodenmais in Bavaria, at Rammelsberg near Goslar in the Harz, and at Fahlun. Other localities are Schemnitz in Hungary, Bilin in Bohemia, and Hurlet near Paisley in Scotland. It is used in dyeing, in manufacturing ink, Prussian blue, and sulphuric acid. The residue of distillation in the last process, named the colcothar of iron, is used as a red pigment, and for polishing steel. 238. BOTRYOGENE, Haidinger, Phillips ; Red Vitriol ; Fer sulfate rouge, Dufrenoy ; Hemiprismatic Botryogen-salt, Mohs. Monoclinohedric ; ooP 119 56' ; the most frequent combination is oo P . (P, rather distinct. Sectile ; H. = 2 2-5 ; G. = 2 2- 1. Trans- lucent, vitreous lustre ; colour hyacinth-red, orange -yellow, and yel- lowish-brown ; streak ochre-yellow. Taste slightly astringent. Par- tially soluble in water, leaving a yellow ochre behind. B.B. intu- mesces and evolves water in the closed tube ; when ignited gives out sulphurous fumes, and then acts like peroxide of iron. Analyses. Sulph. of iron protox. Sulph. of iron proto- perox. Sulph. of mag- nesia. Sulph. of lime. Water & loss. Total. 1 6-77 35-85 26-88 2-22 28-28 100 Berzelius, Fahlun. 2 6-85 39-92 17-10 6-71 31-42 100 Do. Bo. 3 48-3 20-8 ... 30-9 100 Do. Do. Berzeiius considers the sulphates of lime and magnesia as not essen- tial, and proposes the formula p'e 3 's' 2 + Spe s' 2 + 36 H . It occurs with gypsum and epsomite at Fahlun in Sweden. 239. COPIAPITE, Haidinger ; Basisches schwefelsaures Eisenoxyd, Rammelsberg. (a) Foliated. Occurs in six-sided tables, but crystal-system un- certain, and also in granular masses. Cleavage, basal perfect. Trans- lucent ; lustre pearly ; colour yellow. Chem. com. pV 's' 5 + 18 H. Occurs at Copiapo in Coquimbo in Chili. Analysis No. 1. (b) Radiated. Occurs incrusting the former, in masses with a radiated fibrous texture. Colour dirty greenish -yellow. Chem. com. 2 re 's' 2 + 21 H . Analysis No. 2. Sulph. acid. Iron perox. Alu- mina. Lime. Mag- nesia. Silica. Watr. Total. 1 39 '60 2 3173 3 38-9 23-11 28-11 34-4 1-95 l'-91 2-64 0-59 1-37 1-43 29-67 36-56 36 '7 101-34 100-53 100 H. Rose. Do. 4 32-11 5 32-45 6 6-00 7 42-90 4674 49-63 80-73 53-30 = 064 7'88a 5-20& ::: 13-56 13-11 13-57 3-96 100-94 ICO '39 100-30 100-16 Rammelsberg. Scheerer (mean of 2). Do. Meillet. (a) Potesh; (b) Soda. Both substances are probably mixtures of several salts, as Berze- lius has intimated. To these may be added, Fibroferrite of Prideaux also from Chili, No. 3 a corrected analysis, the original having contained 10 per cent, sulphur, earthy matter, and Family.'] COQUIMBITE. 327 loss. It is partially soluble in warm water ; intumesces in hydro- chloric acid, becomes deep yellowish-red, and at length is dissolved, leaving the sulphur and earth. Gelbeisenerx (Yellow Iron-ore) of Breithaupt, No. 4, from the brown coal at Kolosoruk in Bohemia, and No. 5 a similar compound from Modum in Norway. They occur in reniform, or compact and earthy masses ; H. = 2-5 3 ; G. = 2-7 2-9. Opaque ; lustre weak ; colour ochre-yellow. In the closed tube they become red, and evolve first water, then sulphurous acids. Not soluble in water, with difficulty in hydrochloric acid. They are perhaps mixtures of various salts produced during decomposition. No. 6 is a dark-brown salt of iron also from Modum, and still more probably a mixture. Apatelite of Meillet, No. 7, occurs in small reniform earthy masses of a yellow colour in clay, at Auteuil near Paris. It is similar to the yellow iron ore, but has a different composition, = 2po a 's' 3 + 3 H. The Vitriol ochre of Berzelius occurs at Fahlun with botryogen, and is an earthy ochre-yellow substance. Its composition, according to Ber- zelius, is pe 2 "s"+ 6 H with 16 P 00 sulphuric acid, 62'46 iron peroxide, and 21-54 water. When heated it loses water, becomes brown-red, and when highly ignited evolves sulphurous fumes. A similar salt seems, to occur in some of the ochreous mixtures at Rammelsberg near Goslar in the Harz. At the latter place a mixture of the sul- phates of the protoxide and peroxide of iron, with sulphates of copper, zinc, and other metals, is named Misy. 240. COQUIMBITE, Breithaupt, Dana, Dufrenoy; Neutrales schwefelsaures Eisenoxyd, Rammelsberg. Hexagonal, P 58 ; the crystals are thick tabular or short prismatic combinations of OP with ooP and P. Usually in granular aggregates . Cleavage, prismatic along ooP imperfect ; H. = 2 2'5 ; G. = 2 2-1. Colourless, white, also brown, yellow, red, and blue ; taste astringent. B.B. in closed tube evolves water, and then sulphurous vapours, the remainder acting like iron peroxide. Chem. com. p *s* 3 + 9 H.with 28-5 iron peroxide, 43 '6 sulphuric acid, and 28'9 water. Analyses. 1 2 3 Sulph. acid. Iron perox. Alu- mina. Lime. Mag- nesia Silica. Watr. Total. 43-55 43-55 41-37 24-11 25-21 26-79 092 078 1-05 0'78 0-14 0-32 0-21 0-30 0-31 0-37 0-82 30-10 29-98 29-40 100-04 100-24 99-68 H. Rose. Do. J. H. Blake. This salt is found in beds or veins in felspar porphyry, or trachyte, in Chili near Copiapo, and in Bolivia near Calama, where it forms the chief part of a hill. No. 1 was crystallized ; No. 2 fine granular ; 328 TECTIZITE CYANOSE. [Rock Salt and No. 3, according to Blake, was a regular octahedron, in which case the mineral must be dimorphous. 241. TECTIZITE, Breithaupt; Braunsalz, Naumann. Rhombic, dimensions unknown. It forms small pyramidal and aci- cular crystals, sometimes in scopiform groups, or massive. Rather soft and friable ; H. = 1-5 2 ; Gk = 2 nearly. Lustre vitreous or re- sinous ; colour clove-brown. Easily soluble in water, and attracts moisture readily from the atmosphere. B.B. fuses in its water of crystallization. Seems to be a hydrous sulphate of peroxide of iron, but composition unknown. Found in Saxony at Graul near Schwarz- enberg, and at Braunsdorf in the Erzgebirge. 242. CYANOSE, Beudant; Blue Vitriol ; Sulphate of copper, Phillips; Kupfervitriol, Hausmann ; Cuivre sulfate, Hauy ; Tetarto- prismatic vitriol salt, Mohs. Triclinohedric ; the crystals are very unsymmetric, and in consi- derable variety, but oo'P . ooP' . P' forms the basis of most of the combinations, to which OP, ooPoo, and ooPco are very frequently added. The latter two faces (n : r) form an angle of 79 19' ; F (P) is inclined to ooP' (!T) 127 40', to ooPoo (n) 120 50', to ooPoo (r) 103 27', and ooP (T 7 ) to oo'P (M) 123 10' (fig. 183). It seldom occurs naturally in distinct crystals, but more often in stalactitic, Fig. 183. reniform, or other aggregates, and as an incrustation or pulverulent coating. Cleav- age, along ooP' and oo'P very imperfect. Fracture conchoidal ; H. = 2'5 ; G. = 2-2 2-3. Translucent ; lustre vitreous ; co- lour Berlin-blue to azure-blue ; taste very nauseous ; readily soluble in water, from which metallic copper is precipitated by iron. B.B. in the closed tube it evolves water, and becomes white ; and on charcoal, especially with soda, is easily reduced to metallic copper. Chem. com. cu 's* + 5 ii, with 32 protoxide of copper, 32 sulphuric acid, and 36 water. This salt is a secondary production, especially from copper pyrites, and is veiy abundant in solution in the water of some mines, as those of Rammelsberg near Goslar in the Harz, Schemnitz, Orawitza, and Neusohl in Hungary, Klausen in Tyrol, Fahlun, Rio Tinto in Spain, in Anglesea, Cornwall, and Wicklow in Ireland, and many other places. It also occurs among volcanic products, as on the lava of Family.'] GOSLARITE BIEBERITE. 329 Vesuvius. It is seldom found pure ; but, where in sufficient abundance, is used in the manufacture of blue vitriol. The larger part of this sub- stance employed in the arts is, however, formed artificially, either by the roasting and lixiviation of pyrites and other ores of copper. by treating these or the metal with sulphuric acid, or as a residuary pro- duct of metallurgic operations. It is used in dyeing, and in forming blue and green pigments. 243. GOSLARITE, Haidinger ; Sulphate of Zinc, Phillips; Zink- vitriol, Hausmann; Zinc sulfate, Hauy ; White vitriol, Dana; Prismatic vitriol salt, Mohs. Rhombic ; ooP 90 42', isomorphous with epsomite ; usual combi- nation ooP . ooPoo . P (fig. 184). The crystals are prismatic and Fig. 184. lengthened along the chief axis. It is mostly found in granular masses, or stalactitic, reniform, and encrusting. Cleavage, brachydiagonal perfect. H. = 2 2-5 ; G. = 2 2-1. Pellucid ; lustre vitreous ; colour white, inclining to grey, yellow, green, or red. Taste nauseous astringent. Very easily soluble in water. In the closed tube yields water, and, ignited with charcoal powder, sulphuric acid. Chem. com. when pure zn "5" + 7 H. Ana- Zinc Mang. oxide, perox. Sulph. acid. Watr. Total. 1 2 27-5 2174 0-5 6-52 22-0 71'74 50-0 HXH) 100-00 Klaproth, Goslar. Hausmann, Do. a 25-67 4-33 21-60 46-506 99-94 Schaub, Cornwall. (a) With water ; (6) + I'OO copper protoxide, O'i7 iron peroxide, and O'C/ quarz. This mineral seems a recent production from the decomposition of zinc-blende. It is found in the Rammelsberg mine near Goslar in the Harz, at Fahlun in Sweden, Schemnitz in Hungary, Holywell in Flintshire, in Cornwall, at Villefranche in France, and in great beauty near Guipuzcoa in Spain. The artificial salt is used in dyeing and medicine, and prepared either from blende or metallic zinc. 244. BIEBERITE, Haidinger; Sulphate of Cobalt, Phillips; Cobalt Sulfate", Dufrenoy ; Kobaltvitriol, Mohs. Monoclinohedric, similar to melauterite. Usually occurs stalac- titic, or as a flaky efflorescence. Colour pale rose-red. Taste astrin- gent. Soluble in water. In closed tube yields water, and, strongly 330 JOHANNITE NATRON. \_Rock Salt ignited, sulphurous fumes ; in other respects acts like cobalt oxide. Chem. com. (do Mg)'s + 7 H, according to No. 2. Analyses. 1 2 Sulph. acid. Cobalt oxide. Mag- nesia. 3-86 Watr. Total. 1974 29-05 3871 19-91 41-55 46-83 100 98-65 Kopn, Bieber near Hanau. Winkelblech, Do. Occurs in the old mines of Bieber, and also, it is said, at Leogang in Salzburg. 245. JOHANNITE, Phillips ; Uran-vitriol, John ; Hemiprismatic Euchlore-salt, Mohs. Monoclinohedric, C = 85 40', ooP 69. The crystals are similar to those of trona (fig. 186), but are very small, and combined in reniform masses. Cleavage, prismatic along ooP ; H. = 2 2-5 ; G- = 3-19. Semitransparent, vitreous ; colour bright grass -green, with paler streak. B.B. in closed tube yields water, becomes brown, and then acts with borax and salt of phosphorus like peroxide of uranium. Ac- cording to John's researches, it is a hydrous sulphate of the protoxide of uranium. In one variety Berzelius found copper oxide. It occurs very rarely at Joachimsthal and Johann-Georgenstadt. 246. NATRON, Beudant; Carbonate of Soda, Phillips; Soda, Haus- mann ; Naturliches Mineral- Alkali, Werner ; Soude carbo- nate'e, Hauy ; Hemiprismatic Natron Salt, Mohs. Monoclinohedric ; C = 57 40', usual combination of the artificial crystals ( ooPoo ) . ooP . P . ooPco , in acute rhomboidal tables with bevelled edges (fig. 185), and ooP (P) 79 41', P (M) 76 28'. The natural salt occurs in crystalline crusts or as a pulverulent efilorescence. Cleavage, orthodia- gonal distinct, and less so clinodiagonal ; H. = 1 1*5 ; G. = 1'4 1-5. Pellucid ; vitreous ; colourless or greyish-white. Easily soluble in water. B.B. evolves water, and melts easily in its water of crystal- lization, colouring the flame yellow ; fused with silica, effervesces. Chem. com, Na c + 10k, = 21 -8 soda, 15*4 carbonic acid, and 62*8 water. In a natural natron from Debreczin in Hungary, Wackenroder found 89'84 carbonate of soda, 4-34 chloride of so- dium, 1 '63 sulphate of soda, 1*46 phosphate of soda, 0*03 sulphate of potassa, 0'24 carbonate of magnesia, 0-24 carbonate of lime, 0*42 siliceous peroxide of iron, 1-61 silicate of soda, and 0'15 silica ('== 99'96). Fig. 185. Family.] THERMONATRITE. 331 Natron seems in most cases to originate in the decomposition of various rocks or soils. It occurs on many lavas, as those of Vesuvius, Etna, and Teneriffe ; and is common in the trap quarries on the Rhine with carbonate of potash, sulphate of potash, and chlo- ride of potassium. It often forms a pulverulent efflorescence on the ground, as in the plain of Debreczin in Hungary, where about 10,000 cwts. are collected annually ; and also in Bohemia, Spain, Egypt, Persia, Tartary, China, Mexico, and southern Peru. It occurs in solution in many mineral waters and salt lakes, especially those of Egypt. The purified salt is used in the manufacture of soap, and also in dyeing, bleaching, medicine, and for other purposes. 247. THERMONATRITE, Haidinger ; Soude carbonatee prismatique, Dufrenoy ; Prismatic Natron Salt, Mohs. Rhombic ; <*P2 = 107 50', Poo = 83 50' ; usual combination ccPoo . QO P2 . PQO , in rectangular tables with the sides bevelled (fig. 186). Cleavage, brachydiagonal per- fect; H. = 1-5 ; G. = 1-5 1-6. Co- lourless. B.B. acts like natron, but does not melt in its water of crystallization. Chem. com. Na c + H with 50'1 soda, 35'4 carbonic acid, and 14*5 water. Analyses, below. It occurs with natron at several places, and in the natron lakes at Lagunilla in Co- lombia, in the Macarius desert in lower Egypt, and in the Steppes between the Ural and Altai, and is deposited from their water in the warm season. According to Haidinger, a saturated solution of soda at a temperature of 77 to 99 Fahrenheit, and cooling slowly, forms crystals of thermonatrite ; whereas a less saturated solution at a lower temperature forms crystals of natron. Both varieties also occur in the soda of commerce. Haidinger gives 82-26 carbonate of soda and 17 - 74 water as the composition of the artificial salt, but when freed from the solution it agrees with the above formula. Fig. 186. Carb. acid. Soda. Watr. Sulph. acid. Sulph. of soda. Chloride of sodium. Earthy matter. Total. 1 35-1 50-2 14-7 trace 100 Beudant, Debreczin. 2 30-9 3 32-3 43-8 467 13-5 14-0 trace 7-3 3-1 2-7 1-4 5-3 100 101 Do. Egypt. Do. Vesuvius. 832 TRONA GAYLUSSITE BORAX. [Rock Salt 248 TRONA, Phillips, Hausmann, Dufrenoy; Urao, Beudant; Prismatoidal Trona Salt, Mohs. Monoclinohedric ; the crystals formed predominantly by OP and Fig. 187. Po0 ( 103 15 ') ( fi S- 187 >- Tt also forms columnar aggregates. Cleavage, orthodiagonal perfect ; H. = 2-5 3 ; G. = 2-1 2-2. Transparent to translucent ; colourless. Does not decompose in the air. Taste alkaline. B.B. like former species. Chem. com. Na 2 c 3 + 4 H = 87-93 soda, 40*24 carbonic acid, and 21-83 water. Analyses. | Soda. Carb. acid. Watr. Sulph. of soda. Total. 1 2 3 37-0 3862 41-22 38-0 40-13 39-00 22-5 21-24 18-80 2-5 100 99-99 99-02 Klaproth, Fezzan. Beudant, Barbary. Boussingault, Lagunilla. The trona of the Arabs occurs at Sukena near Fezzan, and in other parts of the African desert. The Urao at Lagunilla near Mer da in Columbia. 249. GAYLUSSITE, Boussingault, Phillips, Dufrenoy ; Hemiprismatic Kouphon Haloid, Mohs. Monoclinohedric ; C = 78 27', ooP 68 51', P 110 30' ; the crys- tals often prismatic and lengthened along P. Occur imbedded se- parately in clay. Cleavage, prismatic along ooP imperfect. Fracture conchoidal. H. = 2'5 ; G. = 1-9 1-95. Transparent; lustre vi- treous ; colourless. Slowly and partially soluble in water. In the closed tube decrepitates and becomes opaque. B.B. fuses readily to an opaque bead. Chem. com. Na c + ca c + 5 H, which agrees closely with a recent analysis by Boussingault, who found 34-5 carbonate of soda, 33-6 carbonate of lime, 30'4 water, 1-5 clay (= 100). It occurs at Lagunilla near Merida, in a bed of clay at the natron lakes, and from the form of its crystals is named Clavos (nails) by the natives. 250. BORAX, Beudant ; Tinkal, Hausmann ; Borate of Soda, Phillips ; Soude boratee, Hauy ; Prismatic Borax Salt, Mohs. Monoclinohedric ; C = 73 30', ooP 87, P 120 nearly ; usual combination ooP . ooPoo . ( ooPco ) . OP . P ; almost isomorphous with augite. Twin crystals are frequent, united by a face of ooPoo . Cleavage, orthodiagonal perfect, prismatic along o>P less distinct. Family.'] SASSOLINE. 333 Fracture conchoidal, rather brittle. H . = 2 2'5 ; G. = 1 -7 1-8. Pellucid ; lustre resinous ; colourless, but coloured yellowish, green- ish, and greyish-white. Taste feebly alkaline and sweetish. In the closed tube yields much water. B.B. intumesces greatly, becomes black, and finally melts to a transparent colourless bead, colouring the flame yellow, or, when moistened with sulphuric acid, green. So- luble in 12 parts of cold water. Chem. com. of the pure salt NE *B 2 + 10 H, with 16-37 soda, 36-53 boracic acid, and 47-10 water ; but it often contains many impurities ; and Fownes and Sullivan found in it 2-13 per cent, phosphoric acid. Hutstein states that it crystallizes from a hot solution, at temperatures from 167 to 212 Fahr., in very beau- tiful octahedrons with 6 atoms water ; at lower temperatures in ob- lique rectangular prisms with 10 atoms water. This mineral occurs in loose crystals in the clay on the shore oi some alpine lakes in Thibet and Nepal, along with rock salt. Also in South America near Potosi, and it is said in Ceylon. The pure borax is prepared from this mineral, and forms the most valuable re- agent for blowpipe experiments. It is also used in preparing fine glass, in medicine, and in South America as a flux in melting copper ores. 251. SASSOLINE, Jameson, fJausmann; Boracic acid, Phillips; Acide boracique, Hauy ; Prismatic Borax Acid, Mohs. Triclinohedric according to Miller ; OP : ooPco = 75 30' ; usually fine scaly, or fibrous. The thin crystals or scales are irregular six- sided tables with the edges replaced by oblique planes, or OP . ooP' . o> P . ooPoo . They occur free or combined in crusts, and stalactitic aggregates. Macles frequent, united by ooPoo. Cleavage, basal very perfect. Sectile and flexible ; H. = 1 ; G. = 1-4 1-5. Translucent ; lustre pearly ; generally coloured greyish or yellowish- white. Taste acidulous and slightly bitter. Feels greasy. Easily so- luble in boiling, less so in cold water. In the closed tube yields water. B.B. frothes up and melts easily to a hard, transparent glass, colour- ing the flame green. The solution in alcohol burns with a green flame. Chem. com. B" + 3 H, with 56*3 boracic acid and 43'7 water. Klaproth found in the variety from Tuscany 81*33 hydrous boracic acid, 10-50 sulphate of manganese protoxide, 2*83 sulphate of lime, : 33 iron peroxide, 0-66 alumina, 2-66 silica, and 1-66 carbonate of lime (= 99-97). In a specimen from the same country Wittstein finds 76-50 hydrous boracic acid, 6'56 water, 1-02 silica, 0'32 alumina, 0-29 chloride of ammonium, 1*32 sulphuric acid, with these sulphates, 8*50 of ammonia, 2'63 of magnesia, 0-91 of soda, 0'37 of potash, and 0-36 of iron peroxide (= 99-79). Tn the variety from Vulcano, Stro- 334 NITRE NIT RATI X E . [Hock Salt Fig. 188. M meyer found only a minute amount of sulphuric acid ; and Erdmann ammonia, in one case to 3*18 per cent. It occurs on Vulcano in the Lipari islands, in the hot springs of Sasso near Sienna, and in the lagoni of Tuscany, from which, in 1845, about 2,000,000 Ibs. avoirdupois were procured by evaporating the water. Also in the Andes of Atacamain South America. 252. NITRE, Jameson; Salpeter, Werner; Kalisalpeter, Rausmann ; Nitrate of Potash, Phillips ; Potasse Nitratee, Hauy ; Pris- matic Nitre Salt, Mohs. Rhombic ; ccP (M) 119, 2Poo (P) 71, Poo (*) 110, usual com" bination ooP . GO Poo (K) . 2Pco, the crystals (fig. 188) prismatic. Macles united by a face of ooP. All the forms are isomorphous with those of arragonite. Naturally it only occurs in acicular or capillary crystals, as < flaky or pulverulent coating, or in fine granulai crusts. Cleavage, brachydiagonal and prismatic along ooP indistinct. Fracture conchoidal ; H. = 2 ; G. = 1'9 2. Semitransparent ; vitreous, or silky when fibrous; colourless, white or grey. Taste saline and cooling. Easily soluble in wa- ter. Deflagrates when placed on hot charcoal ; and B.B. on platina wire melts very easily, colouring the flame violet. Chem. com. of the pure salt K '$' with 46'6 potash and 53'4 nitric acid. The natural salt is always more or less mixed with other substances, and, in a va- riety from Molfetta in Apulia, Klaproth found 42-75 nitrate of potash, 25-50 sulphate of lime, 0'20 chloride of potassium, and 30-20 lime- stone (= 98'85). It occurs there as an efflorescence from limestone in the so-called salpetre caves. Similar caves are found near Homburg, as Burkhard's cave, in the limestone rocks of Kentucky, in Brazil west of Tejuco, and in Ceylon. Nitre is also found in considerable amount in Hungary, Podolia, the Ukraine, in Spain, Italy, France, near Mount Sinai in Arabia, in Egypt, Persia, and near Agra in Bengal. In Malta it is formed by the action of the sea water on limestone. It is used for producing nitric acid, in glass-making, medicine, and more especially in the manufacture of gunpowder. 253. NITRATINE, Haidinger ; Natronsalpeter, Naumann ; Nitrate of Soda, Phillips ; Soude nitratee, Hauy ; Rhombohedral Nitre-salt, Mohs. Rhombohedric ; R = 106 30', isomorphous with dolomite. Occurs in crystals of the primary form, and in crystalline grains. Cleavage Family. ,] NITKOCALCITE NITROMAGNESITE. 335 along R rather perfect. H. = 1-5 2 ; G. = 2-1 22. Translu- cent or transparent, with veiy distinct double refraction. Lustre vitreous ; colourless, or greyish and yellowish-white. Taste saline and cooling. Easily soluble in water. Deflagrates on hot charcoal, but less violently than nitre. B.B. fuses on platina wire, colouring the flame yellow. Chem com. of pure salt Na'tf, with 36-6 soda and 63-4 nitric acid. The native salt is generally mixed with common salt and other substances. Analyses. Nitrate of Chloride of Sulph. of Iodide of Watr. Mix- Total. soda. sodium. soda. sodium. 1 9670 1-30 ... 2-00 ...a 1100 Le Canu, Atacama desert. 2 3 64-98 64-00 28-69 29-30 3-00 2-25 0-63 ...c 2-606 99-90 0-506 98-80 Hayes, Tarapaca. Blake, Do. 4 70-20 20-70 5-65 2-20 1-056 99-80 Do. Do. 5 94-29 1-99 ... 1-99 0-20dlOO Hofstetter, Do. (a) With traces of sulphates of alkalis and lime ; (6) shells and marl ; (c) + 2*75 sulphate of magnesia ; (d) sand, + 0'24 sulphate of potash, 0*43 nitrate of potash, and 0'86 nitrate of magnesia. This salt occurs in the district of Tarapaca on the northern fron- tier of Chili, where it forms beds averaging four feet thick, and ex- tending forty leagues in length. It rests on marl containing fragments of shells in a basin-like pampa, and is mixed with various other salts. It has been supposed left by the sea, but the chemical nature of the salt is against this opinion. In 1837, 150,000 quintals of the refined nitratine were shipped from Yqtiique. It is used in the arts as a sub- stitute for nitre ; but is unfit for manufacturing gunpowder from its deliquescing in the air. 254. NITROCALCITE, Shepard ; Nitrate of Lime, Phillips ; Kalk- saltpeter, Hausmann ; Chaux nitratee, Hauy. Occurs in fibrous or pulverulent efflorescences, of a white or grey colour. Translucent. Taste sharp and bitter. Readily soluble in water, and deliquesces in the air. Melts slowly on burning charcoal with slight detonation. Chem. com. 6a 'N* + H, or, by Shepard's analysis, 32-00 lime, 57'54 nitric acid, and 10'56 water (== 100). The specimen was from the limestone caves of Kentucky, where it is very abundant. It is frequent on old walls and limestone rocks, especially near decaying animal matter. 255. NITROMAGNESITE, Shepard; Nitrate of Magnesia, Phillips; Magnesie nitrate'e, Dufrenoy ; Magnesiasalpeter, Naumann. Occurs in the same places with nitrocalcite, with which it agrees in 336 SAL-AMMONIAC MASCAGNINE. [Rock Salt colour and other characters. Taste bitter. Chem. com. probably M g 'ff + H = 24 magnesia, 65 nitric acid, and 1 1 water. 256. SAL-AMMONIAC, Jameson; Muriate of Ammonia, Phillips; Salmiak, Werner ; Ammoniaque muriatee, Hauy ; Octahedral Ammoniac-salt, Mohs. Tesseral ; O, also combinations with ooOoo , cxO, and 202. Oc- curs in crusts, stalactites, and earthy or pulverulent masses. Cleavage, octahedral imperfect ; fracture conchoidal. H. = 1 -5 2 ; G. 1*5 1-6. Pellucid ; vitreous ; colourless, but inclining to grey or yel- low, sometimes to green, brown, or black. Taste saline and pungent. Easily soluble in water. B.B. volatilizes without fusing. With soda on platina wire gives out a strong smell of ammonia ; and on copper wire colours the flame bluish-green. Chem. com. of the pure salt, muriate of ammonia = N H 8 + H CI, with 32 per cent, ammonia ; or chloride of ammonium = N H 4 Cl, with 33'9 ammonium and 66'1 chlorine. In a white crystallized specimen from Vesuvius, Klaproth found only 0*5 per cent, of chloride of sodium ; and in a greyish- white massive sal-ammoniac from Tartary, 2 - 5 per cent, sulphate of ammo- nia. The yellow variety is coloured by chloride of iron or sulphur, with which it is often associated. This mineral chiefly occurs as a sublimate in cracks and fissures near active volcanos. It was found in great abundance in the crater of Vesuvius during the eruption of 1822 ; and is common on Etna, the Solfatara near Naples, the island Vulcano, and Iceland. It is also brought from Bucharia in Tartary. It is sometimes found near ignited coal seams, as at St Etienne in France, near Newcastle, and in Scotland. It is used in medicine, dyeing, and various metallurgic operations, but chiefly prepared by chemical processes. 257. MASCAGNINE, Reuss, Hausmann ; Sulphate of Ammonia, Phillips ; Ammoniaque sulfatee, Hauy ; Prismatic Ammoniac Salt, Mohs. Rhombic, o>P 107 40', Poo 121 16' ; usual combinations ooP . ooPco . P (fig. 189) ; but chiefly in crusts and stalactites. Cleavage, brachydiagonal rather perfect ; seetile ; H. = 2 2'5 ; G. = 1-7 Fig. 189. 1'8. Pellucid, vitreous ; colourless, white or yellowish ; taste pungent and bitter ; easily soluble in water, and attracts moisture from the atmosphere. B.B. when heated decrepitates, then melts, and at length wholly volatilizes. Chem. com. of the artificial salt N H 3 's + H, with 25*9 ammonia, 60*5 sulphuric acid, and 13 '6 water ; Berzelius gives 2 atoms or 23*9 per cent, water, Family.] ARCANTTE THENARDITE EPSOMITE. 337 with 22'8 ammonia and 53'3 sulphuric acid. Occurs, but rarer than sal-ammoniac, in fissures near volcanos, as on Etna, Vesuvius, the Solfatara, the Lipari Islands, and in the lagoni near Sienna in Tus- cany. It also forms in ignited coal beds, as at Bradley in Stafford- shire, with sal-ammoniac. 258. ARCANITE, Haidinger ; Sulphate of Potash, Phillips ; Kali- sulphat, Naumann ; Potasse sulfate'e, Hauy ; Aphthalose, Beudant; Prismatic Pycrochylin-Salt, iWofo. Rhombic in rather acute pyramids, with ooP 120 24', 2Pco 67 38', OP, and other forms. Mostly in crusts or pulverulent coatings. Cleavage, basal imperfect ; H. = 2'5 3 ; G. = 1'73. Pellucid ; vitreous or resinous ; colourless or white, inclining to yellow, exter- nally greenish or bluish ; taste saline, bitter ; soluble in water. B.B. decrepitates, fuses, and on cooling crystallizes (becomes hepatic, Rammelsberg). The solution is precipitated by acetic acid. Chem. com. K *s,'with 54*04 potash and 45'96 sulphuric acid. It is rather rare, but occurs in the lavas of Vesuvius and other volcanos, and in solution in the water of some salt springs. 259. THENARDITE, Casaseca, Phillips, Dufrenoy, Mohs. Rhombic, in rather acute pyramids P, with OP and ooP, combined in crusts and druses. Surface rough, and with little lustre. Cleav- age, basal rather perfect ; fracture uneven ; H. = 2-5 ; G. = 2'6 2-7. Pellucid, vitreous, white ; taste feebly saline 5 easily soluble in water, and acquires a white crust by attracting moisture from the air. B.B. colours the flame deep-yellow, fuses, and on charcoal is reduced to sulphuret of sodium. Chem. com. Na's* with 43-82 soda and 56*18 sulphuric acid. Casaseca found 99-78 sulphate of soda and 0-22 car- bonate of soda in a specimen from Salinas d'Espartinas near Aranjuez, five leagues from Madrid, where it is deposited by the water of the salt springs during the summer months. It is used for preparing soda. 260. EPSOMITE, Beudant ; Epsom-salt, Jameson ; Sulphate, of Magnesia, Phillips; Bittersalz, Werner; Magnetic sulfate'e, Hauy ; Prismatic Bitter-salt, Mohs. Rhombic ; the pyramid P mostly hemihedric, and formed as a rhombic sphenoid, ooP 90 38'. Usual combinations coP . P, and ooP (M) . oopoo (0) . P (7), in prismatic crystals (fig. 190). The natural Ff 338 EPSOMITE. [Rock Sail Fig. 190. M M salt forms granular, fibrous, or earthy aggregates or efflorescences. Cleavage, brachydiagonal per- fect ; H. = 2 2-5 ; G. = 1-7 1'8. Pellu- cid, vitreous, and colourless or white, sometimes pale rose-red ; taste saline, bitter ; easily solu- ble in water. In the closed tube it yields much water with no acid reaction, fuses and conti- nues unchanged. B.B. on charcoal again fuses, loses its acid, incandesces, and shows alcaline reaction. With solution of cobalt becomes pale rose-red. Chem. com. M g 's*+ 7 H, with 16-32 magnesia, 32-53 sulphuric acid, and 51'15 water. Analyses. Mag- nesia. Sulph. acid. Watr. Mang. perox. Iron prot. Total. 1 2 3 4 5 6 7 14-58 16-39 16-50 15-31 17-31 16-20 15-97 32-26 32-30 31-90 31-37 34-37 34-07 32-46 49-24 50-93 51-20 51-70 48-32 47-20 50-60 362 0-34 : 23 : 09a .! 6 ... c 9970 99-85 99-60 99-88 100 99'57 99-86 Stromeyer, Bosjesman River. Do. Idria (hair-salt). Do. Calatayud, Arragon. Do. Neusohl, Hungary (red). Bouis, Fitou, France. Dufre'noy, Do. Osersky, Caucasus. (a) +0-69 cobalt protoxide, and 0-38 copper protoxide; (6) + 2-10 lime; (c) + 0'47 soda and 0-36 mixtures. This salt forms as an efflorescence on various rocks containing magnesia and iron pyrites. It thus occurs in the old coal wastes or alum mines at Ilurlet near Paisley, in the quicksilver mines of Idria, in the gypsum of Montmartre, at Freiberg, and other places. At Neusohl in Hungary it occurs stalactitic (No. 4), and contains water in small cavities, which renders it moist when rubbed. It effloresces from the ground in many parts of Spain, and in great abundance in the Russian Steppes. It is contained in many mineral waters ; and much of that used in commerce is obtained from these, as at Epsom in Surrey (Epsom salts), Saidschiitz and Seidlitz in Bohemia, and other places. It is chiefly used in medicine and in preparing magne- sia. According to Haidinger and Mitscherlich, the crystals of epso- mite formed at a temperature below 60 Fahr. are rhombic; whilst those crystallizing between 77 and 87 are clinohedric. The Astrakanite of Rose occurs in white, transparent, prismatic crystals among the salts in the salt lakes east of the mouth of the Wolga. Its composition is Mg's' + Na's" + 4 H, or, by G. Rose's ana- lysis, 41'00 sulphate of soda, 35-18 sulphate of magnesia, 21-56 water, 0*33 chloride of magnesium, and 1-75 gypsum and sand. Family.'} SIDERITE. 339 The Reussin of Karsten, in white, six-sided, and pointed crystals forming radiating groups, from Seidlitz and Saidschiitz in Bohemia, is similar. Reuss found 66'04 sulphate of soda, 31-35 sulphate of mag- nesia, 2-19 chloride of calcium, and 0-42 sulphate of lime. It seems, however, only a mixture of these salts. m. ORDER. SALINE ORES. I. FAMILY. THE SPARRY IRON ORES. 261. SIDERITE, Haidinger ; Sparry Iron, Jameson ; Spathose Iron, Carbonate of Iron, Brown-spar, Phillips ; Spatheisenstein, Werner ; Spharosiderite, Hausmann ; Fer carbonate, Dufre- noy ; Brachytypous Parachrose Baryte, Mohs. Rhombohedric ; R 107. In the crystals R chiefly predominates, occasionally with OR, R, o>R, 2R, ooP2. The rhombohedrons are often curved, saddle-shaped, or lenticular. It frequently occurs massive, in fine or coarse granular aggregates, more rarely in small botryoidal or reniform shapes (Sphserosiderite) ; also mixed with clay in compact or fine granular masses. Cleavage, rhombohedral along R perfect ; H. = 3'5 4-5 ; G. = 37 3'9. Translucent in various degrees, becoming opaque when weathered. Lustre vi- treous or pearly ; colour rarely white, generally yellowish-grey or yellowish-brown, changing to red or blackish-brown on exposure, when it is converted into thehydrated peroxide. B.B. infusible, but becomes black and magnetic. With borax and salt of phosphorus shows reaction for iron ; with soda usually for manganese. In acids soluble with effervescence. Chem. com. Fe c or carbonate of iron, with 62'6 iron protoxide and 37-9 carbonic acid, but part of the protoxide of iron usually replaced by protoxide of manganese, by magnesia, or lime. Analyses, next page. These analyses, to which many might be added, show the varia- tions in composition of this important mineral. None of them are pure carbonate of iron, which seems never to occur alone, but always mixed with the protoxide of manganese (Nos. 7-13), or with mag- nesia (Nos. 14, 15). The purest is the fibrous variety (Nos. 1, 2) from Steinheim near Hanau, where it occurs in spheroidal masses in the 340 SIDERITE. [Sparry Iron Ore Iron protox Mang protox Lime Mag- nesia. Carb. acid. Vein- stone, &c. Total. 1 63-75 0-75 0-25 34-0 98-75 Klaproth, Steinheim, Hanau. 2 5963 1-89 0-20 38 04 99-91 Stromeyer, Do. Do. 3 53-0 0-6 5 : 4 41-0 100 Berthier, Baigorry, France. 4 53-0 0-8 1-0 4-5 387 2-0 100 Do. Pacho, St Fe de Bogota. 5 63'25 3-00 i-oo 30-00 ...a 99-00 Hisinger, Riddarhyttan. 9 57-91 7 53-5 1-51 6-5 0-59 trace 07 36-61 392 0-606 99-12 999 Karsten, Babkowsky, U. Silesia. Berthier, Rancid, Pyrenees. 8 46-3 9-1 ... 4-5 38-4 1 : 4 99-7 Do. Bendorff, Coblentz. 9 43-0 11-0 2-3 38-0 6-7 100 Do. Allevard, Isere. 10 50-41 7-51 2-35 38-64 0-32 99-23 Karsten, Hachenburg. 11 47-20 8-34 : 63 375 38-85 0-95 9972 Do. Siegen. 12 36-81 25-31 38-35 100-47 Magnus, Ehrenfriedersdorf. 13 43-59 17-87 : 08 6'24 38-22 100 Schnabel, Eisen, Siegen. 14 45 2 0-6 12-2 40-4 ... 98-4 Berthier, Autun, France. J5 42 8 ... 15-4 41-8 100 Do. Allevard, Isere. 16 53-6 ... 3-7 33-5 8-l'd 98-9 Dufr^noy, Poullaouen. 17 43-26 trace 1-89 30-SOc 20-78e 96-23 Phillips, Yorkshire. 18 49 38 ... 1-54 ... 32-48 13 -10/ 100 Dufrenoy, Dudley. 19 45-84 0-20 1-90 5-90 33-63 7 *83o 100-68 Colquhoun, Crossbasket, Glasgow. 20 47-33 0-13 2-00 2-20 33-10 6'63h 100-20 Do. Clyde Iron works. (a) + 175 water; (6) + 1-92 carbon; (c) with water: (d) silica; (e) silica and alumina ; (/ ) do. + 3-50 bitumen, water, and loss ; (g) silica + 2-53 alumina, 1 -86 carbon and bitumen, and 0-99 water; (h) silica, + 4-30 alumina, 1 '70 carbon and bitumen, 0-33 iron peroxide, 0-22 sulphur, and 2-26 water and loss. fine-grained greenstone or anamesite ; of which rock it also forms a constituent. Hausmann has remarked the strong tendency of the si- derite to assume a spherical form, as manifested in the curved faces of its rhombohedrons, and in the similar form which the carbonates of lime or magnesia, when mixed with a small proportion of the car- bonate of iron and manganese protoxide, often assume. This does not destroy its crystalline tendency, and the two structures are found combined. It is also curious that, whilst a small portion of clay destroys the tendency to crystallize, both in this mineral and in calc-spar, a much larger proportion of quartz does not interfere with it. Breithaupt has distinguished the varieties with more than 20 per cent, manganese protoxide (No. 12) as Oligon-spar. The siderite occurs in beds or masses, often of immense extent, especially in Styria and Carinthia. In the Erzberg near Eisenerz in Styria, it rests on gneiss, and is wrought as an open quarry. The Stahlberg and Momel near Schmalkald, the vicinity of Siegen, and Musen in Westphalia, show similar extensive masses ; whilst in An- halt and the Harz it forms large veins in greywacke, or Devonian limestone. Other very extensive deposits of this ore are found in the Pyrenees and the Basque provinces of Spain, as near Bilboa ; and at Pacho near Bogota in New Granada. Most of these localities yield fine crystals ; and these also occur in metallic veins at Joachims- Family.'} SIDERITE. 341 thai in Bohemia, Freiberg in Saxony, Klausthal in the Harz, Beer- alstone in Devonshire, Alston Moor in Cumberland, and in many of the tin mines of Cornwall, particularly the rare hexagonal prisms. The clay ironstone, of grey, blue, brown, or black colours, with G. = 2-8 3'5 ; H. 3*5 4'5, is an impure variety of this mineral. It occurs chiefly in slate-clay or marls, in layers or nodular masses, often containing fossil plants or other organic bodies, which seem to have attracted the carbonate of iron. In these nodules, crystals of siderite, calc-spar, celestine, barytes, quarz, pyrites, blende and ga- lena, often occur. This variety is found occasionally in the transition rocks, but especially in the coal formation of Britain, Belgium, and Silesia, in vast abundance. It is more rare in the oolite and chalk in Northern Germany and England ; and in the brown coal of Radnitz in Bohemia, and other places, frequently forms petrifactions of wood. Nos. 17-20 above are varieties, and the following is the composition of the celebrated black-band Nos. 1-5, and other argillaceous iron ores of Scotland and Wales (vide Mem. of Geol. Survey, vol. i. pp. 186, 187). Carbo- nate of iron. Carbo- naceous matter. Earthy matter. Metallic iron in carbon. 1 70-0 23-0 7'Oa 33-7 Black Band, Lanarkshire. 2 51-04 22-16 26-80 24-6 Cwan Avon bed, S. Wales. 3 63-9 4 79-9 10-0 6-6 26-1 13-5 30-7 36-5 Maesteg valley, Upper bed, Up. Div. Do. Do. Lower Division. 5 79-5 6 86-0 16-4 4-1 14-0 33-4 41-5 Beaufort, Pontypool, 4-inch band. Ystradgunlas, Upper vein. 7 72-4 8 75-4 ... 27-6 24-6 34-9 36-4 Ib. another bed. Pendaren, Red vein. 9 60-9 39-1 29-4 Aberfergwm, nodules. 10 55-5 44-5 26-6 Pendaren, Jack vein. (a) Includes silica, alumina, and trace of lime. The pure variety of this mineral is the ore used in forming the Sty- rian steel, and also in the French Pyrenees and northern Spain. It is either allowed partially to decompose by exposure tp the air, or is roasted, and then converted at once into bar iron or steel. From the clay iron-stone or impure varieties, again, most of the British iron is manufactured ; the carbonaceous matter in the black-band varieties aiding materially in their reduction. The amount of iron produced in Great Britain annually has been estimated at from 1 to 2 million tons, worth about nine millions sterling. In 1846, South Wales alone produced about half a million tons, and Scotland consi- derably above that quantity. The Junkerite of Dufrenoy (No. 10 of table, p. 340), which occurs at Poullaouen in Brittany in small quartz veins in greywacke, is a mere variety of siderite, with which, as Breithaupt has shown, it agrees in crystalline form. 342 ANKERITE DIALLOGITE . [Sparry Iron Ore 262. ANKERITE, Haidinger, Phillips ; Dolomie, Dufrenoy, in part ; Parafcomous Lime-Haloid, Mohs. Rhombohedric, R 106 12', mostly massive and granular. Cleav- age, along R perfect, the cleavage planes often curved ; H. = 3*5 4 ; G. = 2-95 3*1. Translucent or only on the edges ; vitreous, inclining to pearly ; colour yellowish-white or grey, becoming brown when weathered. B. B. becomes black and magnetic ; with soda shows reaction for manganese ; soluble with effervescence in nitric acid, the solution gives traces of lime and magnesia. Chem. com. carbonates of lime, magnesia, iron protoxide, and manganese protoxide in variable proportions. Analyses. Carbo- nate of lime. Carbo- nate of magnes. Carbon, of iron protox. Carb. of manga, protox. Total. 1 2 3 4 50-11 61 -1 50-9 50-5 11-85 25-7 29-0 32-4 35-31 20 '0 18-7 12-3 3-08- 3-0 0-5 ...a 100-35 99-8 99-1 99-5 Schrotter, Hone Wand, Styria. Berthier, Gollrath, Styria. Do. Corniglion, Vizille. Do. Miihlen Gr-aubundten. (a) + 4-3 veinstone and water. This mineral occurs at Rathhausberg in the Valley of Gastein in Salzburg, in beds in mica slate ; and more especially in connection with siderite in. Styria, as at Golrath, Eisenerz, and the Nieder Alp. Other varieties are found in the limestone mountains at Raiding near Vordernberg, on the Rothsol, the Veitsch Alp, and other places. It is valued by the Styrian miners as an ore of iron or flux, and named Rohwand, Rosszahn, and Wandstein. This mineral seems to pass on the one hand into breunnerite ; and on the other, into siderite, by the gradual substitution of isomorphous ele- ments. Nos. 3 and 4 are rather breunnerites, or transition varieties ; and No. 15 of dolomite, p. 291 above, a similar variety connecting this species with dolomite. The variety from the Erzberg in Styria, in which Sanders found 49*61 iron protoxide, 6'67 lime, 5-18 magne- sia, O'lO manganese protoxide, and38'44 carbonic acid (= 100), may indeed be considered a true siderite. 263. DIALLOGITE, Beudant; Manganese-spar; Red Manganese, Allan ; Carbonate of Manganese, Phillips ; Rother Braunstein Manganspath, Werner; Manganese carbonate, Hauy ; Ma- crotype Parachrose Baryte, Mohs. Rhombohedric; R 106 51' (Mohs), to 107 (Breithaupf). The more common forms are R and R, sometimes with OR and ooP2 ; other forms are rare. The crystals are often curved lenticular or saddle- shaped, and generally united in druses. It also forms 'Spherical, reniform, and columnar aggregates, or granular masses. Cleavage, Family.] MANGANOCALCITE. 343 rhombohedric along R, perfect ; H. 3'5 4-5 ; G. 3 -3 3-6. Translucent ; vitreous or pearly lustre ; colour rose-red to flesh-red ; streak white. B.B. usually decrepitates, and becomes greenish-grey or black, but is infusible. With fluxes shows reaction for manga- nese. The powder is slowly soluble in cold, quickly and with effer- vescence in warm hydrochloric acid. Chem. com. M O c with 62 manganese protoxide and 38 carbonic acid, but usually mixed with carbonates of lime, magnesia, or iron. Analyses. Carb. of Mang. prot. Carb. of iron prot. Carb. of Lime. Carb. of Mag- nesia. Water. Total. 1 1 82-2 1 2 7370 3 90-5 4 89-91 5 86-64 6 81-42 7 74-55 8 79-94 7-3 575 3 : i'o 15-01 11-04 8-9 13-08 9-5 6-05 10-58 10-31 trace 2-43 1-6 7-26 3-30 2-43 4-28 6-05 0*44 0-31 0-33 10-lla 6-22a 100 99-84 100 99-70 99-96 99-44 100 100 Berthier, Freiberg* Stromeyer, Do. Berthier, Kapnik. Stromeyer, Do. Do. Nagyag. Kersten, Voightsberg, G. 3-553. Kane, Glendree. Do. Do. (a) With organic matter, &c. + 0-33 (in No. 7)> and 0-37 (in No. 8), sand and clay. This mineral occurs in veins in gneiss and porphyry with ores of silver, galena, fahlore, and blende, at Freiberg, Schemnitz, Kapnik, and Nagyag; with red haematite at Elbingerode in the Harz and Gonzen near Sargansin Switzerland. At the latter a hydrated variety, fibrous, silky, and yellowish or reddish, occurs, and has been named Wiserite. A compact diallogite is found in a tertiary deposit with manganite in Reinhardswald in Hessia. Nos. 7, 8 are analyses of a compact yellowish-grey variety, which forms a layer two inches thick below a bog at Glendree in county Clare, Ireland. Lampadius ana- lyzed a compact diallogite from Kapnik. Mohs distinguished some crystals from Kapnik (R = 107), but on insufficient grounds. The Mangankalk of Hisinger from Langbans- hytta in Sweden contains, according to Beudant, 41-43 carbonic acid, 35-77 lime, and 22*80 protoxide of manganese. 264. MANGANOCALCITE, Breithaupt According to Breithaupt, this mineral forms rhombic crystals ex- actly like those of arragonite, and therefore bears the same relation to diallogite that arragonite does to calc-spar. Rammelsberg found in it 67*48 carbonate of manganese protoxide, 18'81 carbonate of lime, 9-97 carbonate of magnesia, and 3-22 carbonate of iron protoxide ( = 99-48). It occurs at Schemnitz. 344 LANTHANITE PARisiTE CALAMiNE. [Sparry Iron Ore 265. LANTHANITE, Haidinger ; Carbonate of Cerium, Phillips, Dana ; Cerium carbonate, Dufrenoy. Tetragonal ; in small tabular crystals. Usually fine granular or earthy. Cleavage basal ; H. = 2-5 3. Lustre dull or pearly ; colour white or yellowish. B.B. becomes brownish-yellow. Soluble in acids with effervescence. Chem. com. i" a 8 c + 8 H according to Hermann. Hisinger's analysis, corrected by Mosander, who showed that it contained lanthanium, and not cerium, gave 10*8 carbonic acid, 75'7 lanthanium oxide with traces of cerium oxide, and 13*5 water (= 100). It occurs at Bastnaes near Riddarhyttau in Sweden. 266. PARISITE, Bunsen. Hexagonal, P 164 58' ; occurs crystallized in the primary form. Cleavage, basal very perfect. H. = 4-5 ; G. = 4 - 35. Vitreous, on the cleavage planes pearly. Colour brownish-yellow inclining to red. In the closed tube yields water and carbonic acid, and becomes brown. B.B. infusible, and phosphoresces ; with borax forms a yellow glass, becoming colourless when cold. Chem. com. 8 (ce , ca ) c + 2 Ca F + ceri ; or, by Bunsen's analysis, 23-51 carbonic acid, 59*44 protox- ide of cerium, with protoxides of lanthanium and didymium, 3-17 lime, 11-51 fluoride of calcium, and 2-38 water. It Is found in the emerald mines of the Musso Valley in New Granada. 267. CALAMINE, Jameson; Smithsonite, Beudant; Carbonate of Zinc, Phillips ; Galmei, Werner ; Zinkspath, Naumann ; Zinc carbonate", Hauy ; Rhombohedral Zinc-baryte, Mohs. Rhombohedric, R 107 40' ; the more common forms are R, 4 Jft, and R 3 ; OR, |R, 2R, and ooP2, are also known. The crystals generally small or very small, obtuse-edged, and apparently rounded. Usually it occurs inreniform, botryoidal, stalactitic, and laminar ag- gregates, or fine granular and almost compact. Cleavage, rhombo- hedric along R perfect, the planes sometimes curved. Fracture uneven conchoidaL Brittle. H. = 5'0 ; G. = 4-1 4'5 (4-442 a yeUow crystal). Translucent or opaque ; lustre pearly or vitreous ; colour- less, but often coloured pale greyish-yellow, brown, or green. B.B. becomes white, loses its carbonic acid, and acts like zinc oxide. It sometimes forms in the reducing flame a dark-yellow or red ring on the charcoal from cadmium oxide. Soluble in acids with effervescence ; also in solution of potash. Chem. com. z n c , with 64'5 zinc oxide and 35'5 carbonate of lime, but seldom pure. Analyses, next page. Family.'] CALAMINE. Carbonate of Silicate of zinc. Total. Si /V -WJN '^S-tyVr ] RNIA. j> ^ ~~~~--^r Zinc oxide. Iron prot. Mang. prot. Lime. Mag- lies i a. Lead oxide. 1 96-00 2 60-35 3 55-89 4 84-92 2-03 32'21 36-46 1-58 4-02 3-47 6-80 1 : 90 2-27 1-58 0-14 2*84 1-12 2-49 0-41 1-85 99-15 101-11 98-50 99-57 v. Kobell, Nertschinsk. Monheim, Altenberg, G. 4-15. Do. Do. G. 4-04. Do. Do. G. 4-20. Smithson, in a variety from Somersetshire, found 64 -8 oxide of zinc and 35*2 carbonic acid ; in another from Derbyshire, 65*2 oxide of zinc and 34'8 carbonic acid. Berthier analyzed many varieties in which the carbonate of zinc varied from 30 to 90 per cent., the other components being carbonates of iron, manganese, lead, and lime. This mineral occurs in beds or veins in the crystalline and transi- tion rocks, and also in the carboniferous and oolite formations. It is most common in limestone, and is often associated with calc-spar, quartz, blende, and ores of iron and lead. Chessy near Lyons, the Altenberg near Aix-la-Chapelle, Brillon in Westphalia, Tarnowitz in Silesia, Carinthia, Hungary, Siberia, Jefferson county in Missouri N. America, are a few of its foreign localities. Mendip in Somerset- shire, Matlock in Derbyshire, Wanlockhead and Lead Hills in Scot- land, also yield this mineral. A compact, fibrous, pale-yellow variety occurs at Alston Moor. The zinc is obtained from this mineral chiefly by distillation, and it was formerly used for manufacturing brass. In Silesia cadmium is also obtained from it. The Kapnite of Breithaupt includes the varieties with more than 15 per cent, of iron protoxide. They have often a brownish-yellow colour, lower specific gravity than the others, and more resemblance to siderite. The Zinc-bloom (Zinkbluthe), distinguished from calamine by Smith- son, seems a mere produce of its decomposition. It occurs in reni- form earthy masses, of a pale-yellow colour, and shining streak. A specimen from Bleiberg contained 71'4 zinc oxide, 13-5 carbonic acid, and 15-1 water (Smithson) ; corresponding to z n 3 c + 3 H, or, as Eammelsberg thinks, a hydrous carbonate of zinc mixed with hydrate of zinc oxide. It yields water in the closed tube, but otherwise agrees with calamine. It is found at Bleiberg and Raibel in Carinthia. The Herreiite of Del Rio, from Albarradon in Mexico, is said to be rhombohedric, but is only found massive, with curved cleavage planes. H. = 4 5 ; G. = -4-3. Translucent ; pearly or vitreous ; and pistacio, emerald, or grass-green. B.B. on charcoal becomes grey, fumes, and stains the charcoal white. In the closed tube it yields white fumes, condensing in transparent drops. It consists > 346 GALMEI. [Sparry Iron Ore according to Del Eio, of carbonates of zinc oxide and nickel oxide ; according to Herrera, of tellurium, with carbonate of nickel oxide ; but is probably a mere mixture. 268. GALMEI, Werner; Electric Calamine, Jameson; Siliceous oxide of Zinc, Phillips ; Zinksilicat, Nauman n; Zinc oxide" silicifere, Hauy ; Prismatic Zinc-Baryte, Mohs. Rhombic, and hemimorphic ; P (P) with polar edges 101 9' and 132 9'; ooP2 (d) 103 53', 00 (o) 116 40', Pao (I) 128 26'. The more common combinations are ooPco (s) . ooP2 . ^Poo , and ooPoo . o>P2 . Poo (fig. 191). The crystals are small, and either long and tabular, or short and broad prismatic. They are frequently bounded at the lower end by the pyramid P. They occur attached and in druses, or combined in diverging spheroidal or reniform groups. It also occurs in fine columnar and fibrous aggregates of similar forms, or granular, compact, and earthy. Cleav- age, prismatic along o>P2 very perfect, brachydo- matic along Poo perfect. H. = 5 ; G. = 8-3 3'5. Transparent to translucent ; lustre vitreous, and on ooPoo pearly ; colourless or white, but often vari- ous light tints of grey, and also of yellow, green, brown, and blue ; becomes electric by heat, the upper end of the crystal in the figure being the analogue, the lower the antilogue pole. Where two such crystals are united in the direction of their axes, the ana- logue poles are at the ends, the antilogue in the middle. In the closed tube it yields water. B.B. decrepitates slightly, but is infusible, or melts with great difficulty only on the edges. With so- lution of cobalt becomes blue on the fused edges, otherwise green. Readily soluble in acids, when the silica gelatinizes. Chem. com. 3 zn 2 si + 4 H, with 25-1 silica, 65'2 zinc oxide, and 9'7 water ; but No. 7 gives the simpler formula zn 2 si + ii, with 25'7 silica, 66'8 zinc oxide, and 7 '5 water. Analyses, next page. Occurs with calamine in most localities, especially at Raibel and Bleiberg in Carinthia, Aix-la-Chapelle, Iserlohn, Taraowitz, and Nertschinsk. In concentric botryoidal groups in the Mendip Hills, and at Wanlockhead, and in various pseudomorphs after calc-spar in Derbyshire. It is used as an ore of zinc, and in the manufacture of brass. Family^} WILLIAMITE TRIPLITE. 347 Silica. Zinc oxide. Watr. Lead oxide. Total. 1 2 3 4 5 6 25-0 25-0 25-5 23-2 25-38 25-96 24-89 68-3 66-0 64-5 66-8 62-85 65-66 66-84 4-4 9-0 10-0 10-8 9-07 8-38 7-46 270 : 27 97-4 100 100 100-8 100 100 99-92 Smithson, Retzbanya. Berthier, Limburg. Do. Breisgau. Thomson, Leadhills. Hermann, Nertschinsk (G.= 3-871). Do. Do. (G.-3-435). Berzelius, Limburg. (a) With tin oxide + 0-54 carbonic acid. 269. WILLIAMITE, Levy ; Brachytype Zinc-Baryte, Mohs. Rhombohedric ; R 128 3CX ; usual combinations o>R . R, the crys- tals small, often very small. It also occurs massive and reniform. Cleavage, basal rather perfect, prismatic along ooR imperfect ; brittle ; H. = 4-5 ; G. = 4-1 4-2. Translucent or transparent ; lustre dull resinous ; colour white, yellowish, or brown. B.B. in closed tube yields much, water, otherwise acts like galmei. Chem. com. zn 2 si = 72'47 zinc oxide and 27*53 silica. Analyses. \i Silica. Zinc oxide. Mang. perox. Iron perox. Alu- mina. Watr. Total. 25-00 26-97 27-34 71-33 68-77 70-82 2-66 0-67 1-48 1-816 : 66a 1-25 99-66 99-91 99-97 Vanuxem, New Jersey. Thomson. Rosengarten, Uppel Silesia la} + 0*78 alumina with zinc and iron ; (6) protoxide. Found with galmei at Aix-la-Chapelle, Liege, and Raibel, and at Franklin in NeW Jersey. 270. TRIPLITE, Hausmann ; Phosphate of Manganese, Jameson, Phillips; Eisenpecherz, Werner; Manganese phosphate" fer- rifere, Hauy ; Prismatic Retin-Baryte, Mohs. Rhombic, but dimensions unknown, having only been found massive and coarse granular. Cleavage in three directions at right angles to each other, one rather perfect, the second less distinct, the third im- perfect. Fracture flat conchoidal or uneven ; H. = 5 5*5 ; G. = 3-6 3-8 j translucent or opaque ; lustre resinous ; colour chesnut- brown or blackish-brown ; streak yellowish-grey. In the open tube (or with sulphuric acid, Gmelin) shows traces of fluorine. B.B. on charcoal fuses easily, with strong intumescence, to a black metallic, highly magnetic globule ; with soda on platina wire forms a green glass ; with borax in the outer flame a glass coloured by manganese, in the inner by iron. Soluble in hydrochloric acid. Chem. com., accord- ing to Berzelius, M n 4 'P' *p'*= 34 iron protoxide, 33 manganese protoxide, and 33 phosphoric acid. Analyses, next page. 348 ZWIESELITE TRIPHYLINE. [Sparry Iron Ore 1 2 Iron. Manga- nese. Phospho- ric acid. Phosphate of lime. Total. 31 a 31 -9& 42 a 32-66 27 82-8 3-2 100 IVauquelin, Limoges 100-5 JBerzelius, Do. (a) Peroxide; (&) protoxide. It occurs with beryl in a quartz vein in granite at Limoges in France. 271. ZWIESELITE, Breithaupt; Eisenapatit, Fuchs, Dufrenoy. Rhombic, but hitherto only massive. Cleavage in three directions, basal rather perfect, brachydiagonal less perfect, prismatic along o>P 129 veiy imperfect. Fracture conchoidal or uneven ; H. = 4*5 5 ; Gr. = 3*95 4. Translucent on the edges ; lustre resinous ; co- lour brown ; streak yellow. B-B. decrepitates and fuses easily to a bluish-black magnetic globule. With fluxes acts like triplite. Easily soluble in warm sulphuric acid, showing traces of fluorine. Chem. com. 2 Fe 3 *p* + Mn 3 *P* + Fe F, or, by Fuch's analysis, 35*60 phos- phoric acid, 35*44 iron protoxide, 20*34 manganese protoxide, 4*76 iron, 3*18 fluorine, 0*68 silica (= 100.) It occurs at Zwiesel in Bava- ria ; and externally is very like triplite, but its chemical composition is analogous to that of apatite. 272. TRIPHYLINE, Fuchs, frc. Rhombic, but dimensions unknown ; chiefly found in coarse granu- lar, crystalline masses. Cleavage, basal perfect, prismatic along o>P 132, and brachydiagonal imperfect. H. = 4 6 ; G. = 3*5 3*6. Translucent on the edges ; lustre resinous ; colour greenish- grey with blue spots, but when weathered becomes brown and opaque ; yields water in the closed tube. B.B. fuses very easily to a dark steel-grey magnetic bead, colouring the flame pale bluish-green or red, the green more distinct when it is moistened with sulphuric acid. With borax shows reaction for iron, with soda for manganese. Easily soluble in hydrochloric acid, the residue after evaporation imparting a purple- red colour to the flame of alcohol. Chem. com. 6 (p e 3 , Mn 3 ) P" + Li 3 'P* with 42*64 phosphoric acid, 49*16 iron protoxide, 4*75 man- ganese protoxide, and 3*45 lithia. Phospho- ric acid. Iron prot. Mang. prot. Lithia Silica. Mag- nesia. Watr. Total. 1 41-47 2 35-70 3 42-6 4857 48-17 38-6 4-70 8'94 12-1 3-40 8-2 0-53 1-40 17 0-68 5-30 9935 99-51 103-2 Fuchs, Bodenmais (fresh), Do. Do. (weathered,, Berzelius, Keiti. Family.] HUREAULITE HETEROZITE. 349 Triphyline occurs at Rabenstein near Bodenmais in Bavaria in granite. No. 3 is Tetraphyline or Perowskine from Keiti in Tammela parish in Finnland. The latter agrees in general character with the triphyline, but is yellow when fresh, and black when weathered. The last three minerals are closely allied to each other, and also to the following two species. 273. HURBAULITE, Alludud, Dufrenoy ; Huraulite, Phillips, Mohs. Monoclinohedric ; C = 68, ooP 62 30', P 88 ; usual combina- tion ooP . OP . P, the faces of the prism vertically striated, and the crystals small. Also in rounded masses, with a columnar or granular texture, and drusy surface. Cleavage unknown ; fracture conchoidal or uneven. H. = 3 -5 ; G. = 2-27. Translucent ; lustre resinous ; colour reddish-yellow or brown. Yields water in the closed tube. B.B. fuses easily to a black metallic-looking globule. Soluble in acids. Chem. com. 3 Mn 5 * 2 + Fe 5 ''i>' 2 + 32 H, or R 5 * 2 + 8 H. An analysis by Dufrenoy gave 38-00 phosphoric acid, 11-10 iron prot- oxide, 32-85 manganese protoxide, 18'00 water (= 99-95). It is found in geodes and small veins in granite at Hureaux near Limoges in France. Beraunile of Breithaupt occurs in small foliated and radiated masses, with one distinct and one indistinct cleavage at right angles. H. = 2 ; G. = 2-87. Lustre vitreous or pearly on the cleavage faces ; colour hyacinth-red or reddish-brown ; streak reddish ochre-yellow. According to Plattner, it consists of phosphate of iron peroxide and water. In the closed tube yields water. B.B. in forceps melts and colours the flame bluish-green. Soluble in hydrochloric acid. It is found with other phosphates of iron in the limonite at St Benign a near Beraun in Bohemia. Some analyses of kakoxene (see wavellite) are similar. 274. HETEROZITE, Alluaud, Dufrenoy, Mohs ; Heteposite, Phillips, Naumann. Rhombic or monoclinohedric, but only found massive. Cleavage, prismatic along ooP 100, and macrodiagonal ; fracture uneven. Rather easily frangible. H. *= 4*5 5-5 ; G. = 3-39 3'6 (when fresh 3-524, Dufrenoy). Opaque, or when light coloured, translucent on the edges ; lustre vitreous or resinous ; colour dark-violet or la- vender-blue, to greenish-grey. Streak violet-blue or crimson-red. B.B. fuses to a dark-brown or black globule, with semimetallic lustre. Soluble in hydrochloric acid. Chem. com. 2 pe 5 'i>' 2 + Mn 5 '* + 6 H, or a 5 * 2 + 2 ft. Dufrenoy's analysis gave 41-77 phosphoric acid, 350 ALLUAUDITE PITTICITE. [Sparry Iron Ore 34-89 iron protoxide, 17*57 manganese protoxide, 4-40 water, and 0-22 silica (=98 -85). Occurs in granite at Bureaux near Limoges in France. Fuchs considers it a weathered triphyline, which it much resembles. 275. AIXUAUDITE, Damour. Rhombic probably ; with cleavage in three directions at right angles to each other, one very easily obtained, the second less so, the third imperfect. Occurs massive. Fracture scaly and shining. H. above 4 ; G. = 3-468. Translucent on the edges, or opaque ; lustre dull ; colour clove-brown ; streak yellowish-brown. In the closed tube it decrepitates and yields a little water. B.B. on platina wire fuses to a black magnetic globule ; in the outer flame soluble in salt of phos- phorus, with reaction for manganese. In hydrochloric acid, when cold, forms a black solution, which, when heated, becomes yellowish- brown. Difficultly soluble by long digestion in warm nitric acid. Chem. com. (M D , Na) 8 *' + re ** + H, according to Damour, who found, on a mean of several analyses, 41-25 phosphoric acid, 25'62 peroxide of iron, 23-08 manganese protoxide, 1-06 manganese perox- ide, 5-47 soda, 2-65 water, and 0'60 silica (= 99 -73). It occurs in the pegmatite of Chanteloube near Limoges in the Haute-Vienne in France, along with vivianite and dufre'nite. The alluaudite analyzed by Vauquelin was a variety of the latter. 276. PITTICITE, Hausmann Eisenpecherz, Karsten ; Pitchy iron ore, Phillips ; Eisensinter, Werner ; Iron Sinter, Allan ; Ar- seneisensinter, Naumann ; Fer oxide resinite, Hauy ; Uncleav- able Retin-Allophane, Mohs. Amorphous, reniform, and stalactitic. Brittle ; fracture conchoi- dal. H. = 2 3; G. 2-3 2-5. Semitransparent or translucent on the edges. Lustre resinous, inclining to vitreous ; colour yellow- ish, reddish, or blackish-brown, sometimes in spots or stripes. Streak light ochre-yellow or yellowish-white. In the closed tube yields much water, with acid reaction. On ignition emits sulphurous odours. B.B. on charcoal fuses easily, with effervescence and strong arsenical fumes, to a black magnetic globule. Easily soluble in hydrochloric acid to a yellow fluid. Chem. com. according to Stromeyer's analysis, re AS + re s" + 15 H = 35 iron peroxide, 26 arsenic acid, 9 sul- phuric acid, and 30 water. Analyses, next page. This mineral occurs in many old mines, especially those near Frei- berg, and also at Schneeberg in Saxony, Pless in Silesia, and Bleistadt in Bohemia. It is evidently a recent product, probably from the de- composition of mispickel. According to Freiesleben, it is first fluid, Family.'] DIADOCHITE. 351 Iron perox. Mang. perox. Arsenic acid. Sulph. acid. Watr. Total. 9. 33-10 35 0-64 trace 26-06 10-04 14 29-26 30 99-10 99 Stromeyer, Freiberg. Laugier, Do. 3 40-45 30-25 28-50 99-20 Kersten, Do. 4 5 54-66 58-00 ".'. 24-67 28-45 5-20 4-36 15-47 12-59 100 100 Rammelsberg, Gastein. Do. Do. and gradually separates in a solid form. Nos. 3 and 4 seem mixtures of various metallic salts. It agrees in all external characters with the diadochite. 277. DIADOCHITE, Breilhaupt. Reniform and stalactitic, with a curved lamellar structure. Frac- ture conchoidal ; veiy easily frangible ; H. = 3 ; G. = 2-035. Trans- lucent or opaque ; lustre resinous, inclining to vitreous ; yellow or yellowish-brown ; streak white. In the closed tube it yields water. B.B. colours the flame green, intumesces slightly, and fuses on the edges to a black magnetic enamel ; with fluxes shows reaction for iron. Chem. com. p'e *p 2 + 4 p'e 's'+ 32 H, according to L. Gmelin, from Plattner's analysis No. 1. 1 2 3 Iron perox. Phospho- ric acid. Sulphu- ric acid. Watr. Total. 36-69 34-20 36-62 14-81 16-04 16-57 15-15 30-35 49-76 46-81 100 100 100 Plattner. Dumont. Do. Diadochite is a recent formation found in the alum-slate mine near Grafenthal and Saalfeld in Thuringia. The Ddvauxine of Dumont, Nos. 2, 3, is an allied but probably distinct species from Vise" in Belgium. It is redddish (No. 2) or blackish (No. 3) brown, or yellow. H. = 2-5 ; G. = 1-85. B.B. decrepitates, and fuses to a grey magnetic bead. In hydrochloric acid forms a brown solution. In the original analyses from 9 11 per cent, of carbonate of lime, and 3 '6 4-4 per cent, silica were found. A mineral named delvauxine was twice analyzed by Mr Sandall, who found 52-37 iron peroxide, 40'19 water, 3-95 silica, 2-62 phosphoric acid, and 0-87 lime (= 100). This substance is evidently distinct, and probably a mixture. The Karphosiderite of Breithaupt, reniform, opaque, resinous, and straw-yellow, with a greasy feel, is closely related. H. = 4'5 ; G. = 2-5. B.B. becomes red and fuses to a black magnetic bead. It is found in fissures of mica slate on the coast of Labrador ; and, accord- ing to Harkort, consists of hydrous phosphate of iron with a little oxide of zinc. 352 DIOPTASE CHRYSOCOLLA. [Copper-Salts II. FAMILY. COPPER-SALTS. 278. DIOPTASE, Hauy ; Kupfer-Smaragd, Werner; Emerald Copper, Phillips ; Rhombohedral Emerald Malachite, Mohs. Rhombohedric (probably hexagonal and tetartohedral) ; R 126 17', 2R95 48', most common combinations ooP2 (s) . 2R (r) (fig. 192). Fig. 192. The crystals generally short prismatic, and at- tached or united in druses. Cleavage, rhom- bohedral along R, perfect ; Brittle ; H. = 5 : G. = 3 '2 3-3. Transparent or translucent ; lustre vitreous ; colour emerald-green, some- times verdigris -green or blackish-green ; streak green. In closed tube yields water. B B. in the outer flame becomes black, in the inner red, but is infusible ; colours the flame green. On charcoal with soda forms a dark glass, en- closing a grain of copper. Soluble, and gela- tinizes in hydrochloric or sulphuric acid, and also in ammonia. Chem. com. c u si + H = 38-7 silica, 50 copper protoxide, and 11*3 water. Analyses. Silica. Copper prot. Watr. Iron prot. Alu- mina. Lime. Mag- nesia. Total. 1 36-60 48 '89 12-29 2-00 ... 99-78 Hess. 2 3 36-85 36-47 45-10 50-10 11-52 11-40 0'42a 2-36 339 0-356 0-22 99-43 9874 Do. Damour. (a (Peroxide; (6) carbonate. This mineral has only been found in numerous small veins and druses along with calc-spar in a bed of compact limestone in the clayslate of the low hills of Altyn-tubeh, in the middle Kirghis Steppe, about 100 versts from Kar-Karaly. It was first brought to Europe by Bueharian merchants, and sold as emerald. 279. CHRYSOCOLLA, /amesora; Kupfergriin, Copper-green, Werner; Kieselmalachit, Hausmann; Cuivre hydrosilicieux, Hauy; Euchromatic Opaline-Allophane, Mohs. Botryoidal, reniform, or investing ; also massive and disseminated, or rarely forming pseudomorphs after azurite. Brittle ; fracture con- ehoidal and fine splintery ; H. = 2 3 ; G. = 2-0 2-3. Trans- lucent on the edges, or semitransparent ; lustre weak resinous, or Family.'] AZURITE. 353 dull ; colour verdigris to emerald-green or azure-blue ; streak greenish- white. B.B. and with acids acts like dioptase. Chem. com. du si + 2 H = 34-83 silica, 44'94 copper protoxide, and 20-23 water. Analyses. Silica. Copper protox. Iron perox. Watr. Carb. acid. Vein- stone. Total. 1 40 40 12 8 100 Ullmann, Siegen. 2 36-54 40-00 1-00 20-20 2-10 99-84 v. Kobell, Bogoslowsk. 3 35-0 39-9 3-00 21-0 1-1 100-00 Berthier, Do. 4 26-0 41-8 2-5 23-5 37 2-5 100 Do. Canaveilles. 5 35-4 35-1 28-5 1-0 100 Do. Somerville, N. J. 6 37-25 45-17 17-00 99-42 Bowen, Do. 7 35-14 43-07 l-09a 20-36 99-66 Scheerer, Satersdal, Norway. 8 40-0 9 9-66 42-6 13-00 1-4 59-00 16-0 18-00 100-00 99-66 Beck, Franklin, N. J. v. Kobell, Turjinsk, Ural. (a) With alumina, lime, and potash. No. 7, dried at 212, had G. = 3'317 ; No. 9, of a brown colour, is a mixture with limonite, and some of the others were probably also impure. It seems a secondary production from the decomposition of copper ores, which it usually accompanies at the above localities, and also in Cornwall, Hungary, the Tyrol, Moldawa in the Bannat, in Spain, the Harz, Mexico, and Chili. Fine pseudomorphs occur at Bogoslowsk in the Ural, and the crystals mentioned by Hauy (right rhombic prisms of 103 20') were probably of this nature. The Malachitkiesel, Siliceous-malachite of Zincken, from Lauter- berg in the Hartz, seems only a variety of chrysocolla. The Kup- ferblau of Breithaupt, from the Schappachthal in Baden, also agrees with it, except in its somewhat greater hardness (=4 5) and higher specific gravity (= 2'56). Plattner finds in it 36'3 per cent, copper, = 45'5 of copper protoxide. The Kupferblau of G. Kose, from Tur- jinsk in the Ural, light azure-blue, with bluish- white streak, is per- haps distinct. In warm hydrochloric acid the copper is dissolved with violent effervescence, leaving the silica in the form of the assay. 280. AZURITE, Beudant ; Blue Copper, Jameson ; Blue Carbonate of Copper, Phillips ; Kupfeiiasur, Werner ; Cuivre carbonate bleu, Hauy ; Hemiprismatic Lasur-Malachite, Mohs. Monoclinohedric ; C = 87 39', ooP (M} 99 32', P (#) 106 14'. The greater number of crystals consist essentially of OP . ooP . ooPco . P, or A, jfcf, s, k', in fig. 193 of a common form from Chessy as drawn by Mohs, who places the crystals in a different position from that here assumed after Naumann and G. Rose, who make If the ver- tical prism ocP. Many still more complex forms also occur. The crystals are usually short prismatic or thick tabular, but occasionally 354 MALACHITE. [Copper-Salt* Fig. 193. lengthened along the orthodiagonal. Single crystals are rare, more commonly they are combined in druses or groups. It also occurs massive, and disseminated in ra- diated or compact and earthy varie- ties. Cleavage clinodomatic along (Poo ) (P) 59 14', rather perfect. Fracture conchoidal, or uneven and splintery ; H. = 3'5 4 ; Gr. = 3-7 3-8. Translucent or opaque ; lustre vitreous ; colour azure-blue, the earthy varieties (and streak) smalt-blue. In the closed tube it gives out water and becomes black. B.B. on charcoal fuses and yields a grain of copper. Soluble with effervescence in acids, and also in ammonia. Chem. com. c'u 3 c 2 + H, with 69 '09 protoxide of copper, 25*66 carbonic acid, and 5'22 water. Analyses. Copper oxide. Carb. acid. Watr. Total. 1 70 24 6 100 Klaproth, Turjinsk, Ural. 2 8 69-08 68-5 25-46 25-0 5-46 6-5 100 100 Phillips, Chessy, Lyons. Vauquelin, Do. Do. The azurite occurs in beds or veins, chiefly with malachite and other ores of copper. The finest crystals are found at Chessy near Lyons in France, in a great variety of forms, and very brilliant colours. Kolywan and Nischne-Ta-gilsk in Siberia also furnish fine specimens ; and those from Moldawa in the Bannat, though small, are very dis- tinct. It has also been occasionally found near Redruth in Cornwall, at Alston moor, and Wanlockhead. Massive varieties occur in Corn- wall, and earthy in Thuringia, the Harz, and Hessia, and in great abundance in the Permian rocks on the west side of the Ural. Where in sufficient quantities, it is valued as an ore of copper. 281. MALACHITE, Werner; Green Carbonate of Copper, Phillips; Cuivre carbonate vert, Hauy ; Hemiprismatic Habroneme- Malachite, Mohs. Monoclinohedric, C = 61 49', ooP 103 42'; but distinct crystals are rare, the most common being the prismatic combination ooP (AT) . ooPoo (s) . OP (P), again united in macles by a face of ooPoo (fig. 194). In general, it occurs acicular and capillary, thin tabular, and scaly, or in botryoidal, reniform, stalactitic aggregates, with a curved la- mellar or radiated fibrous structure, often becoming compact. Also massive, disseminated, and encrusting, or as a pseudomorph after azuilte or cuprite (red-copper-ore). Cleavage, basal and clinodia- Family. ,] Fig. 194. MALACHITE. 355 gonal very perfect. The massive varieties have partly a diverging and radiated fibrous, or very fine splintery fracture. H. = 3'5 4 ; G. = 3'6 4. Transpa- rent or translucent only on the edges ; lustre adaman- tine or vitreous in the crystals ; silky or dull in the aggregates ; colour emerald and other shades of green ; streak apple-green. B.B., and with acids, acts like azurite. Chem. com. cu c + H, with 71*8 copper protoxide, 20 car- bonic acid, and 8-2 water. Analyses. M 1 2 3 Copper oxide. Carbon, acid. Watr. Total. 70-5 70-10 72-2 18-0 21-25 18-5 11-5 875 9-3 100 100-10 100 Klaproth, Turjinsk (compact). Vauquelin, Chessy (fibrous). Phillips, Do. Do. Malachite seems in many cases a recent production, caused by the action of the water and carbonic acid of the atmosphere on other cop- per ores. It is slightly soluble in water, containing carbonic acid, and hence its stalactitic forms and wide dissemination in rocks may be explained. The foliated, fibrous, compact, and earthy malachites have been distinguished, but they all appear together, and pass into each other. The foliated or crystalline varieties are rare, but occurred at Rheinbreitenbach on the Rhine, and Zellerfeld in the Harz . Beau- tiful specimens of the fibrous variety are found at Chessy in France, at Saalfeld in Thuringia, Moldawa in the Bannat, in the old mine at Sandlodge in Zetland, and in several places in North America and Australia. The compact variety is found chiefly at Falkenstein near Schwatz in the Tyrol, but also in Cornwall, Wales, and Ireland. The copper mines of Siberia and the Ural furnish the finest specimens of malachite, often in masses of immense size. One mass at Nischne Tagilsk was estimated to weigh 15,000 pouds, or half a million pounds. It is a valuable ore of copper, and the finer varieties are prized for ornamental purposes, from their brilliant colours and high polish. The Lime- Malachite, KalkmalacMte of Zinken, occurs microcrys- talline, in reniform, and botryoidal masses, with a radiated fibrous or foliated structure. Brittle ; H. = 2 -5. Lustre silky ; colour verdigris- green. In the closed tube it yields water, and becomes black. B.B. becomes black and fuses to a black slag, which with soda gives copper. Soluble in hydrochloric acid, leaving gelatinous gypsum (Zinken). It seems a hydrous carbonate of copper and carbonate of lime, with sul- phate of lime and some iron. It occurs at Lauterberg in the Harz, but is perhaps only an impure malachite. The Mysorine of Thomson from Mysore in the East Indies, compact, blackish -brown, and soft, with G. = 2*62, seems a mixture of a carbonate of copper with iron peroxide. 356 AURICHALCITE CHALCOPHYLLITE. \Copper-SdtlS 282. AUKICHALCITE, Botlger. Occurs in acicular crystals, H. == 2. Translucent, pearly, and ver- digris-green. In the closed tube yields water, and becomes black. B.B. on charcoal in the inner flame forms a deposition of zinc oxide, and with fluxes gives reaction for copper. Soluble with effervescence in hydrochloric acid. Chem. com. nearly zn 3 c + Cu 2 c + 3 H , with 29-2 copper protoxide, 447 zinc oxide, 16-2 carbonic acid, and 9 *9 water. Analyses. Copper protox. Zinc oxide. Lime. Carbonic acid. Watr. Total. 1 28-19 2 28-36 45-84 45-62 ... 16.05 16-08 9-95 9'93 100-05 99-99 Bottger, Loktewsk. Do. I>o. 3 32-5 4 29-46 5 29-00 427 32-02 41-19 8 : 62 2-16 27 21-45 19-88 5 8-45 7-62 102-7 100 99-85 Connell, Matlock. Delesse, Loktewsk. Do. Chessy, G. = 3.32. The Aurichalcite occurs at Loktewsk and other places in the Altai, with calcspar. No. 3 seems identical in composition, but the quantity analyzed was only 316 grains, and it contained also traces of magne- sia and lime. Buratite of Delesse, Nos. 4 and 5, is azure-blue, and in most cha- racters agrees with aurichalcite, but differs slightly in composition, being perhaps (cu 2 , zn 2 , Ca 2 ) c + H ; or a malachite, with part of the copper protoxide replaced by zinc protoxide and lime. It ac- companies galmei at Loktewsk ; and, according to Delesse, similar substances are found in the maremma of Volterra in Tuscany, at Framont in Tyrol, and in Siberia. 283. CHALCOPHYLLITE, Breithaupt ; COPPER-MICA, Jameson ; Kupfer- Glimmer, Werner; Rhomboidal Arseniate of Copper, Phillips ; Rhombohedral Euchlore-Malachite, Mohs. Rhombohedral, R 68 45' (Brooke). The crystals are always ta- bular from the predominance of OR (o), bounded on the sides by Fig. 195. faces of R (fig. 195). It occurs in small druses and foliated masses. Cleavage, basal very perfect. Sectile. H. = 2 ; G. = 2 -4 2-6. Translucent or trans- parent; lustre pearly on OR, on other faces vitreous inclining to adamantine ; colour emerald to grass or verdigris-green ; streak light- green. In closed tube decrepitates violently and yields much water. B.B. on charcoal in powder emits arsenical vapours, andfuses to a grey metallic grain, which, fused with soda, yields pure copper. Easily soluble in acids and ammonia. Analyses, next page. Family.-] TIROLITE. 357 Arsenic acid. Copper protox. Iron protox. Watr, Alu- mina. Phos- phoric acid. Total. 1 21 2 43 58 39 21 17 ... 100 99 Chevenix. Vauquelin. 3 17-51 4 19-35 5 21-27 44-45 52-92 52 30 2-92 31-19 2394 22-58 3-93 1-80 1 1-29 2-13 1-56 100 99-30 99-84 Hermann (G. = 2-435). Damour (G. =2-659). Do. (Do.) The above analyses are all of specimens from Cornwall. Hermann rejects the phosphoric acid and alumina as impurities, and adds the protoxide of iron to the copper, which gives the formula c'u 8 AS + 23 H, with 49-61 copper protoxide, 18 02 arsenic acid, and 32-37 water. Damour again rejects the alumina and adds the phosphoric to the arsenic acid, and gives du 6 A'S + 12 H, with 51 '6 copper protox- ide, 25 arsenic acid, and 23 '4 water. These formulae do not, how- ever, well express the analyses, which again differ widely from each other. It is also remarkable that Nos. 3, 4, 5 all contain phosphoric acid and alumina, which thus seem essential constituents. This mineral has been chiefly found with other copper ores in veins in killas in Cornwall, especially in Tingtang, Wheal Gorland, and Wheal Unity mines near Redruth. Also, it is said, near Saida in Saxony, and at Moldawa in the Bannat. 284. TIROLITE, Haidinger ; Kupferschaum, Werner, Allan, Phillips ; Copper Froth, Dana ; Prismatic Euchlore Malachite, Mohs. Crystallization unknown (rhombic, Hausmanri). Only found in reniform, or small, massive aggregates with a radiating foliated texture and drusy surface. Cleavage in one direction very perfect ; sectile. Thin laminaa flexible ; H. = 1-5 2 ; G. = 3 3*1. Translucent ; lustre pearly colour verdigris-green to azure-blue ; streak similar but paler. B.B. decrepitates violently and fuses to a steel-grey bead. On charcoal yields arsenical odours. Soluble in acids, evolving carbonic acid ; and in ammonia leaves carbonate of lime. Chem. com. perhaps hydrated arseniate of copper with carbo- nate of lime, or (c u 5 A'S + 10 H) + da c, or by von KobelFs ana- lysis of a variety from Falkenstein, 43*88 copper oxide, 25'01 arsenic acid, 17-46 water, and 13'65 carbonate of lime (= 100). But the water is nearer 9 atoms, and the carbonate of lime perhaps accidental. It occurs in beds and veins with other copper ores, especially at Falken- stein and other parts of the Tyrol. Also at Libethen in Hungary, Reichelsdorf in Hessia, Saalfeld in Thuringia, Schneeberg in the Erzgebirge, Campiglia near Piombino in Italy, in Asturia and at 358 ERIN ITE LIROCONITE . [Copper -Salts Linares in the Sierra Morena in Spain, and at Matlock in Der- byshire. 285. ERINITE, Haidinger, Phillips ; Monotomous Dystome- Malaehite, Mohs. Porodine and amorphous (Breithaupt) in reniform masses with con- centric foliated structure, rough surface, and conchoidal fracture ; H. 4-5 5 ; G. = 4 4-1. Translucent on the edges ; dull resinous lustre ; colour emerald or grass- green ; streak similar. Chem. com. c'u 5 i's* + 2 H, or by an approximative analysis by Turner, 59'44 copper protoxide, 33*78 arsenic acid, 5 -01 water, 1-77 alumina (== 100). It occurs at Limerick in Ireland with olivenite and other copper ores. According to Haidinger, erinite has a crystalline or relatively symmetrical structure, with scarcely perceptible traces of cleavage in one direction. The same name is applied to the chal- cophyllite (especially Nos. 3, 4, 5 above) ; and Thomson has also given it to a wholly distinct mineral (compare p. 221 above). 286. LIROCONITE, Beudant ; Linsenerz, Werner ; Octahedral Ar- seniate of Copper, Phillips; Chalcophacite, Glocker ; Pris- matic Lirocon-Malachite, Mohs.^ Rhombic ; usual combination P = 119 45', Poo = 71 50'. The crystals Fig. 196. (fig- 196) are small and combined in druses. Cleav- age, prismatic along Poo imperfect, and along Poo still less perfect ; II. = 2 2'5 ; G. = 2-8 3"0. Trans- lucent ; lustre vitreous, or resinous on fracture ; colour azure-blue to verdigris-green ; streak paler. In the closed tube does not decrepitate, yields much water, and becomes green ; then begins to ignite, and appears brown. B.B. on charcoal emits arsenical vapours, and fuses with intumescence to a mass containing grains of copper. Soluble in acids and in ammonia. Chem. com. c'u 8 'As + A! "Is + 24 H, with 36'6 copper protoxide, 11'9 alumina, 26'6 arsenic acid, and 24*9 water. Analyses. 1 2 3 4 5 Copper protox. Alu- mina. Iron perox. Arse- nic acid. Phos- phoric acid. Water. Total. 35-19 3773 36-38 37-18 37-40 8-03 8-61 10-85 9-68 10-09 3-41 3-66 0-98 2079 22-29 23-05 22-22 22-40 3-61 3-87 3-73 3-49 3-24 22-21a 23-84 25-01 25-49 25-44 100-26 100 100 98-06 98-47 Trolle-Wachtmeister. Do. corrected. Hermann (G. = 2-985). Damour (G. = 2-9C4). Do. Do. (a) + 4-04 silica and 2-95 veinstone (omitted in No. 2). Family^ OLIVENITE. 359 These analyses are of varieties from Cornwall, where this mineral has been chiefly found, as in Wheal Unity and other mines near Red- ruth in veins with quartz and ores of copper and iron. It is also found in small crystals at Herrengrund in Hungary and Ullers- reuth in the Voightland. Breithaupt describes this mineral as mono- clinohedric, and Damour says the azure-blue crystals he analyzed belonged to the same system. 287. OLIVENITE, Jameson ; Olivenerz, Werner ; Right Prismatic Arseniate of Copper, Phillips ; Pharmakochalcit, Hausmann ; Prismatic Oliven-Malachite, Mohs. Rhombic ; ocP 92 30', Poo 110 50', usual combination ooP (r) . Fig. 197. p^ tals are short or long prismatic, or acicular ; and either attached singly or united in druses. It also occurs in spherical and reniform ag- gregates with a fine columnar or fibrous tex- ture. Cleavage, prismatic (along r), and brachydomatic (along Z), very imperfect , H. = 3 ; G. = 4-2 4-6. Pellucid in all degrees ; lustre vitreous, resinous, or silky ; colour leek, olive, or blackish-green, also yellow and brown ; streak olive-green or brown. In the closed tube yields water and becomes first green, then greyish-black. B.B. in the forceps fuses easily to a dark-brown, adamantine bead covered with radiating pris- matic crystals. On charcoal, detonates, emits arsenical vapours, and is reduced to copper. Soluble in acids and ammonia. Chem. com. c'u* (is*, 'P') + H, with 56'5 copper protoxide, 39 '5 arsenic acid, and 4 water. Analyses. 1 2 3 4 5 6 7 Copper oxide. Arse- nic acid. Phos- phoric acid. Watr. Total. 56-43 56-2 56-65 56-38 56-86 54-98 51-03 3671 399 39-80 33-50 34-87 40-61 40-50 3-36 5 : 96 3-43 i : oo 3-50 3-9 3-55 4-16 3-72 4-41 3-83a 100 100 100 100 98-88 100 100 v. Kobell, massive. Richardson, do. Do. acicular Hermann, (G. = 4-135). Damour (G. = 4-378). Thomson, fibrous. Hermann, fibrous (G. = 3 - 913.) (a) + 3 64 protoxide of iron. The specimens were from Cornwall, where this mineral has been chiefly found in veins with other arseniates of copper, especially in the mines of Carrarach, Tin Croft, Gwennap, and St Day. It also 360 EUCHROITE KLINOCLASE. [Copper -Salts occurs in less beauty at Alston Moor ; at Kamsdorf and Saalfeld in Thuringia ; at Schwatz in the Tyrol, in the Bannat, at Nischne- Tagilsk in Siberia, in Asturia, Chili, and several other places. Like the other arseniates of copper, it seems a recent formation from the decomposition of fahlore containing arsenic. 288. EUCHROITE, Breithaupt, Phillips ; Prismatic Emerald Malachite, Molis. Rhombic, o>P 117 20', Poo 87 52' ; usual combination ooP ( M ) . o>P2 (7) . OP (P) . Poo (n) (fig. 198). Crystals short prismatic, smaU, and vertically striated. Cleavage, prismatic and brachydomatic im- perfect ; rather brittle ; H. = 3 '5 4 ; G. = 3 '35 3*45; transparent or translucent ; lustre vitreous ; colour emerald or leek-green ; streak verdigris-green. In the closed tube yields water without decrepitating, but becomes yel- lowish-green, and friable. B.B. in forceps fuses, and on cooling forms a greenish-brown crystallized mass ; on charcoal detonates and fuses with arsenical odours, leaving a grain of copper. Ignited with charcoal powder in the open tube it yields a sub- limate of arsenic and arsenious acid. Easily soluble in nitric acid.. Chem. com. c u 4 iv + 7 H = 47'1 copper protoxide, 34-2 arsenic acid, and 18*7 water. Analyses. Copper oxide. Arsenic acid. Lime. Watr. Total. 1 2 3 4 47-85 46-97 46-99 48 '09 33-02 34-42 32-42 33-22 1-12 18-80 19-31 19-31 18-39 99-67 100-70 99-84 99-70 Turner. Kuhn. Do. Wohler. Wohler also found traces of iron, nickel, and phosphoric acid. This mineral has hitherto occurred only at Libethen near Neusohl in Hun- gary in a quartzose mica slate. 289. KLINOCLASE, Brdthaupt; Strahlerz, Werner, Allan ; Oblique prismatic Arseniate of Copper, Phillips ; Aphanese, Beudant ; Abichite, Haidinger; Diatomous Habroneme-Malachite, Mohs. Monoclinohedric, C = 85, o>P 56, usual combination o>P . Poo . Poo , in which the two hemidomes form a horizontal edge of 100 42'. Crystals prismatic in the direction of ooP. It also forms wedge- shaped and hemispherical aggregates, with a radiated columnar tex- ture. Cleavage, basal highly perfect, the cleavage planes in the ag- Family.] BHOSPHOROCHALCITE. 361 gregates curved. H. = 2'5 3 ; G. = 4'2 4-4. Translucent or opaque ; lustre vitreous ; pearly on the cleavage planes ; colour exter- nally blackish-green, internally dark verdigris-green inclining to sky- blue ; streak bluish-green. B.B. becomes black when heated, and on charcoal leaves a grain of malleable copper. It is soluble in acids and in ammonia. Chem. com. cu 6 A'S + 3 H, or cu 2 AS* + 3 cu k, analogous to the phosphorochalcite, with 62'6 copper protoxide, 3O3 arsenic acid, and 7-1 water. Analyses. Arse- Phos- Cop- 1 | nic phoric per Watr.l * ron Lime. : Silica. Total. acid. acid. prot. jperox. 1 29-71 2 27-08 0-64 1-50 60-00 62-80 7-64 7-57 0-39 0-49 0-50 1-12 100-0 99-44 Rammelsberg (G.= 4-258). Damour (G.= 4-312). Found chiefly with other copper ores in veins in Cornwall (Nos. 1 and 2), and also. near Saida in the Erzgebirge. The specific gravity of No. 1 in powder was 4*359. 290. PHOSPHOROCHALCITE, v. Kobell ; Hydrous Phosphate of Copper, Phillips ; Cuivre phosphate, Hauy ; Pseudomalachite, Hausmann ; Hemiprismatic Dystome Malachite, Mohs. Monoclinohedric \ the most common forms are ( ooP2) (f^ 38 56', P (P) 117 49', united with the almost horizontal basis OP (a) and coPoo (e), combined in short prismatic crystals (fig. 199) ; usually Fig. 199. small and indistinct. It is more common in spherical, reniform, or botryoidal masses, with a radiated, fibrous texture, and drusy surface. Cleavage, orthodiagonal imperfect. Fracture uneven and splintery. .H. = 5 ; G. = 4-1 4-3. Translucent, but in gene- ral only on the edges. Lustre adamantine or resinous ; colour blackish, emerald, or ver- digris-green. B.B. decrepitates when heat- ed quickly, when slowly blackens and fuses to a black globule containing a grain of copper. When this globule is fused with an equal volume of lead, a coat of phosphate of lead, crystallizing when cold, forms round the copper granule. Moistened with hydrochloric acid it colours the flame blue. Easily soluble in nitric acid or ammonia. Chem. com. according to Kiihn, cu 6 "p + 3 H, with 70-8 copper protoxide, 21'2 phosphoric acid, and 8 water ; according to Arfvedson and Hermann, cu 5 "p + 2 H, with 68*9 cop- per protoxide, 24'8 phosphoric acid, and 6-2 water. Analyses, next page. Hh 362 THROMBOLITE LIBETHENITE. [Copper-Salts Copper oxide. Phosphoric acid. Water. Total. 1 68-13 30-95 99-08 Klaproth, Rheinbreitenbach. 2 62-85 21 09 15-45 99-99 Lynn, Do. 3 68-20 24-70 5-97 98 '87 Arfvedson, Do. 4 68-74 21-52 8-64 9890 Kuhn, Do. (mean of 3). 5 67-25 24-55 8-20 K'O Hermann, Do. (G. = 4-4j. 6 68-75 23-75 7-50 100 Do. Nischne-Tagilsk (G. = 4-25). 7 67-73 23-47 8-80 100 Do. Do. iG. =.4-00). 8 68-21 25-30 6-49 100 Do. Do. (Dihydrite) jG. 4'4). .9 71-73 10 69-61 20-87 24-13 7-40 6-26 100 100 Kuhn, Hirschberg, Voightland. Do. Libethen, Hungary. 11 67-00 24-22 8-78 100 Do. Do. This mineral occurs in beds in greywacke, with quartz and various ores of copper, on the Virneberg near Rheinbreitenbach in Rhenish Prussia ; and also at Nischne-Tagilsk in the UraL Hermann names No. 8 Dihydrite, as it contains about a fifth less water, but in other respects it agrees with phosphorochalcite, and is probably not distinct. Nos. 10 and 11 are a fibrous variety, with a concentric foliated struc- ture, which Ktihn names Copperdiaspore, because when ignited it is thrown about violently without decrepitating. No. 11 nearly agrees with Ehlite. There is still much uncertainty regarding the composi- tion of this and the other phosphates of copper. 291- THROMBOLITE, Breithaupt, Dana. Porodine, with conchoidal fracture ; rather brittle. II. = 3 4 ; G, = 3'38 3 -40. Opaque ; lustre vitreous ; colour emerald, leek, or dark-green. In closed tube yields much water and becomes black. B.B. colours the flame blue and then green ; on charcoal fuses to a black globule, which spreads out and shows grains of copper. With boracic acid and iron wire, it gives reaction for phosphoric acid. Chem. com. cu 3 p' 2 4- 6 H, orbyPlattner's approximate analysis, 41-0 phos- phoric acid, 39-2 copper protoxide, and 16'8 water (== 97'0). It is found with malachite on limestone at Retzbanya in Hungary. 292 LIBETHENITE, Breithaupt ; Phosphate of copper, Phillips ; Olivenerz, Werner, in part ; Diprismatic Oliven-Malachite, Mohs. Rhombic, most common combination o>P . Poo . P, forming short 1 2 3 4 Copper protox. ric acid. Wate, Total. 63-9 64-8 66-94 65-89 28-7 22-8 29-44 28-61 7-4 9-Oa 4-05 5'50 100 99-2 100-43 100 Berthier, Libethen, crystallized. Do. Do. compact. Kuhn, Do. crystallized. Hermann, Tagilsk. (a) +1-0 carbonic acid and 1-6 iron peroxide. Family.'] TAGILITE EHLITE. 363 Fig. 200. prismatic crystals (fig. 200) with ooP (w) = 95, and Poo (o) = 112 (according to Rose, 92 and 109). The crystals are small, and attached singly or in druses. Cleavage, brachydiagonal and macrodiagonal imperfect. H. = 4 ; G. = 3-6 3'8. Translucent on the edges ; lustre resinous ; colour leek, olive, or blackish-green ; streak olive-green. B.B. and with acids acts like the phosphorochalcite. Chem. com. c'u 4 '' + H, with 66*37 copper protoxide, 29-86 phosphoric acid, and 3'77 water. Analyses, foot of page 362. The above formula is that given by Kiihn's analysis, No. 3, from which No. 4 only differs in containing rather more water. Ber- thier's analysis, No. 1, contains twice the water, or 2 H , and agrees with that by Rhodius of ehlite below, which is probably the same mineral under a different name. . It occurs at Libethen in Hungary with quartz, euchroite, and cop- per pyrites in mica slate. It is also found at Tagilsk in the Ural, and in small quantity near Gunnislake in Cornwall. It is isomorphous with olivenite, whence G. Rose conjectured it should have a similar chemical composition, which is now confirmed by analysis. 293. TAGILITE, Hermann. Forms fungoid, warty, or botryoidal masses, with a rough, earthy surface, and radiating fibrous or earthy fracture. H. = 3 ; G. = 3*5. Colour emerald-green, or when weathered mountain-green. Chem. com. Cu 4 * + 3 H, or, according to Hermann's analysis, 62-38 cop- per protoxide, 26-91 phosphoric acid, and 10-71 water (== 100). The original was mixed with about 2 per cent, of hydrated peroxide of iron. It occurs at Nischne-Tagilsk on limonite. 294. EHLITE, Breithaupt. Botryoidal or reniform masses with a radiating foliated texture, and smooth shining surface. Also compact and disseminated. Cleav- age, in one direction perfect. H. = 1-5 2 (even 4 (?) Hermann) ; G. = 3-8 4-27. Translucent on the edges ; lustre pearly on the cleavage faces ; verdigris-green in the interior, on the surface almost emerald-green. Streak pale verdigris-green. B.B. when heated it breaks into small fragments, which are thrown about violently, other- wise it acts like phosphorochalcite. Chem. com. Cu 5 ** + 3 H, with 66-84 copper protoxide, 24-06 phosphoric acid, and 9-10 water. Ana- lyses, next page. 364 ATACAMITE. [Copper-Salts 25? Phospho- ric acid. Water. Total. 1 65-99 24-93 9-06 99-98 Bergemann, Ehl. 2 6574 8-56 ... Do. Do. 64-85 ... 8-93 Do. Do. 4 5 66-86 63-1 23-14 28-9 10-00 7-3 100- 993 Hermann, Nischne-Tagilsk. Rhodius, Ehl, (G. = 4-27.) Occurs at Ehl near Rheinbreitenbach, at Nischne-Tagilsk in the Ural, and at Libethen. Hermann includes in this species Klihn's cop- per-diaspore (No. 10 of phosphorochalcite above), on account of its similar action before the blowpipe. No. 5 seems distinct. Compare Libethenite, No. 292 above. 295. ATACAMITE, Jameson; Muriate of Copper, Phillips; Salz- kupfererz, Werner; Cuivre chlorure, Dufrenoy ; Prismatoidal Habroneme -Malachite, Mohs. Rhombic, ooP 112 45', Poo 107 10', the most frequent combination is ooP . ooPoo . POD (fig. 201 ), in small prismatic crystals, usually com- Fig. 201. bined in aggregates. It also occurs reniform and massive, with a columnar or granular structure. Cleavage, brachydiagonal perfect. H. = 3 3'5 ; G-. = 4 4'3 (3'7, Breiihaupf). Semitransparent or translucent on the edges ; lustre vitreous ; co- lour olive, grass or emerald-green; streak apple - green. B.B. colours the flame bluish-green, fuses, and leaves a grain of copper. In the closed tube yields water with acid reaction, and with a stronger heat a green sublimate ; easily soluble in acids. Chem. com. Cu Cl + 3 c u + 3n, with 55'85 copper protoxide, 14*86 copper, 16'61 chlorine, and 12-68 water; or, in analysis, 74-46 copper protoxide and 17-09 hydrochloric acid. Analyses. Copper protox. Muria- tic acid. Watr. Total. 1 2 72-0 76-5 16-3 10-5 117 12-5 100 100 Klaproth, compact (cor. by Ram. ) Proust, Do. 3 70-5 11-5 18-0 100 Do. sandy. 4 73-0 16-2 10-8 100 J. Davy, crystallized. 5 50-OOa 14-92& 2175 100 Berthier, from Cobija. (a) + 13-33 copper ; (6) chlorine. This mineral occurs at Remolinos, Santa Rosa, and other places in Chili, in veins in the older rocks with quartz, limonite, malachite, and other copper ores. At Tarapaca in Bolivia it is found in veins with ores of silver. It is also said to occur with the iron ore at Family.~\ VOLBORTIIITE ARSENIOSIDERITE. 365 Schwarzenberg in Saxony. The compact variety forms a crust on some lavas, as on Etna, and especially on those of Vesuvius of A. D. 97, of 1804, 1820, and 1822. This salt often appears on copper long exposed to the atmosphere or sea water, and is the aerugo nobilis seen on antique bronzes. On some of these from Egypt Haidinger observed it crystalline. In South America it is used as an ore of copper, and sent as such to England. 296. VOLBORTHITE, G. Rose. Hexagonal ; in small tabular crystals, OP . ocP, either single or united in spherical groups or foliated masses. H. = 3 ; G. = 3 '55. Colour olive- green ; streak almost yellow. In the closed tube yields water, and becomes black. B.B. on charcoal fuses easily, and in a stronger heat forms a graphite-like slag, containing grains of copper. With soda is reduced to metallic copper ; on platina wire with salt of phosphorus, in the inner flame, forms a green, in the outer flame a yellow glass. Soluble in hydrochloric or nitric acids. Chem. com. probably a vanadiate of copper oxide. Found at Syssersk and Nischne-Tagilsk in Siberia, and on haus- mannite at Friedericksrode in Thuringia, as a secondary production. 297. ARSENIOSIDERITE, Dufrenoy. Macrocrystalline, in spherical aggregates composed of easily sepa- rable fibres. Friable, and leaves a mark on paper. H. = 1 2 ; G. = 3 '88 (Rammelsberg), 3 '52 {Dufrenoy). Opaque ; lustre metallic pearly. Colour ochre-brown, becoming darker in the air. Streak brownish-yellow. B.B. fuses easily, with reaction for iron and ar- senic. Chem. com. c a 5 A'S + 3 re 3 A'S -+ 11 H, with 39 '0 arsenic acid, 40*7 iron peroxide, 11-9 lime, and 8*4 water. Analyses. Arsenic acid. Iron perox. Mang. perox. Lime- Potash. Silica. Water. Total. 1 34-26 2 39-16 41-31 40-00 1-29 8'43 12-18 0-76 4-04 8-75 8-66 98-84 100 Dufre'noy. Rammelsberg. Rammelsberg found that it contains no silica, but a minute portion of manganese in the iron. It occurs in the deposits of manganese ore at Romane>che near Ma^on in France. 298. PHARMAKOSIDERITE, Hausmann; Arseniate of Iron, Phillips ; Fer arseniate, Hauy, Wurfelerz, Werner; Cube ore, Jame- son ; Hexahedral Lirikon-Malachite, Mohs. Tesseral, and tetrahedral-semitesseral. The crystals usually con- sist of the cube ooOoo , with J , or with ooO ; also a trigonal dode- 366 PHARMAKOSIDERITE SCORODITE. [Copper-Salts cahedron approaching very near to the cube. They are mostly very small and collected in druses. Cleavage, tesseral very imperfect. Rather brittle. H. = 2 '5 ; G. = 2'9 3. Semitransparent to trans- lucent on the edges ; lustre adamantine or resinous ; colour olive- green, pistacio to emerald-green, honey -yellow, and brown ; streak straw-yellow. Pyro-electric. In closed tube yields water, becomes red, and intumesces slightly. B.B. on charcoal fuses easily with strong arsenical odours to a steel-grey magnetic slag. Easily soluble in acids. Chem. com. according to Berzelius, Fe 3 X's + re 3 X's 2 + 18 H, with 40'4 arsenic acid, 28*1 'iron peroxide, 12-6 iron protoxide, and 18'9 water. His analysis gave 40-20 arsenic acid, 2*53 phospho- ric acid, 37'82 iron peroxide, 0*65 copper protoxide, 18'61 water, 1-76 veinstone (=101-57). The older analyses of Vauquelin and Chevenix are imperfect. It is rather rare, but occurs in great beauty with other copper ores at Wheal Gorland, Wheal Unity, and Carharrak in Cornwall, coating cavities in quartz. Also at St Leonard in the Haute- Vienne in France ; Langeborn in the Spessart ; Lobenstein in Reuss ; Graul near Schwar- zenberg in Saxony ; and in some parts of North America. Levy distinguished a variety from Horhausen in Nassau under the name Beudantile, but it agrees in crystallization, and so far as known also in composition with phar makosiderite. 299. SCORODITE, Breithaupt, Phillips, Dufrenoy ; Peritomous Fluor-Haloid, Mohs. Rhombic ; the rather acute fundamental form (P), with polar edges 115 and 102 generally predominates in the combinations, along with ooPoo and ooPco (r) ; sometimes also with OP (k) ooP2 (d) Fig. 202. 119, and 2Poo (m) 48 (fig. 202). The crystals are small, pyramidal, and grouped in druses. It also occurs in fine colum- nar, fibrous, and compact aggregates. Cleavage, prismatic along ooP2 imper- fect ; rather brittle ; H. = 3'5 4 ; G. = 3-1 3-2. Translucent; lustre vitreous ; colour leek-green to greenish- black, also indigo-blue, red, and brown. In closed tube yields water and becomes yellow. B.B. on charcoal fuses easily, emitting arsenic vapours, to a grey metallic and magnetic slag. Easily soluble in hy- drochloric (not in nitric) acid, forming a brown solution. Chem. com. Family.] SYMPLESITE BROCHANTITE. 367 Fe AS" "t~ ^ HI with 49'8 arsenic acid, 34'6 iron peroxide, and 15'6 water. Analyses. Arsenic acid. Iron perox. Water. Total. 1 50-78 34-85 l.V55a 101-85 Berzelius, Antonio Pereira, Brazil. 9 49.6 34-3 16-96 101-2 Boussingault, Loaysa, Popayan. 3 4 8 6 50-95. 51-06 52-16 50-96 31-89 32-74 33-00 33-20 15-64 15-68 15-58 15-70 98-48 99-48 100-74 90-86 Damour, Vaulry (G. =-3 - ll) ; green crystals. Do. Cornwall, bluish crystals. Do. Schwarzenberg, Saxony. Do. Brazil (G. = 3 -18 1. 7 48-05 36-41 15-54 100 Hermann, Nertschinsk. (at + 0-67 phosphoric acid, and trace of copper protoxide ; (b) + 0-4 protoxide of lead. Count Bournon named this mineral Cupreous arseniate of iron, Chevenix having found in it 22*5 per cent, of copper protoxide, pro- bably an impurity, as R. Phillips showed that it contained no copper. No. 1 was named Neoctese by Beudant, but agrees in form and com- position with the others. Nos. 2 and 7 are amorphous varieties, the latter named an iron-sinter. Scorodite is probably a secondary production, from the decompo- sition of ores containing arsenic and iron. At St Austle in Cornwall, Vaulry in France, Schlackenwald and Schonfeldin Bohemia, it occurs in veins of tin ore ; at Antonio Pereira, in great beauty, in cavities and fissures in gotheite or brown iron ore ; and at Loaysa near Marmato in veins with gold. 300. SYMPLESITE, Breithaupt. Monoclinohedric, like gypsum, but dimensions unknown. It occurs in very fine prismatic crystals, often almost microscopic ; and also in scopiform groups or masses. Cleavage in one direction very per- fect. Rather sectile ; H. = 2-5 ; G. = 2 957. Transparent or trans- lucent ; lustre vitreous, but pearly on the cleavage planes ; colour pale indigo to celadine-green, with bluish-white streak. In the closed tube it yields water (25 per cent.), then arsenic acid, and becomes brown. B.B. on charcoal emits strong arsenic odours, becomes black and magnetic, but does not fuse. With fluxes shows reaction for iron and trace of manganese. Chem. com. according to Plattner, arseniate of iron protoxide with water, and also a little sulphuric acid and prot- oxide of manganese. It occurs with siderite at Klein-Friesa near Lobenstein in Reuss. 301. BROCHANTITE, Levy, Phillips ; Prismatic Dystome Malachite, Mohs. Rhombic, Poo . JP oo , with other forms, are short prismatic, and vertically striated. 368 VIVIANITE. [Copper- Salts It also occurs reniforra with a fine columnar structure. Cleavage imperfect. H.=3'5 4; G. = 3'75 3'9. Transparent or trans- lucent; lustre vitreous, but pearly on the cleavage planes; colour emerald or blackish-green ; streak bright-green. In the open tube yields water and sulphurous acid. B.B. on charcoal fuses, leaving a grain of copper. Easily soluble in acids. Chem. com. c'u '' + 3 c'u H = 70-28 copper protoxide, 17-76 sulphuric acid, and 11-96 water. Analyses. Copper protox. Sulphu- ric acid. Water. Tin oxide. Lead oxide. Total. 1 2 3 4 5 6 62-63 66-94 68-34 69-52 66-2 67-75 17-13 17-43 18-69 18-10 16-6 18-83 11-89 11-92 12-97 12-38 17-2 12.81 8-18 3-15 0-03 1'05 99-86 100.49 100 100 100 100 Magnus, Hezbanya. Do. Do. No. 1 corrected, Do. No. 2 do. Do. Berthier, Mexico. Forchhammer, Iceland. This mineral occurs in small distinct crystals on malachite at Kez- banyain Hungary, at Katharinenburg in Siberia, and at Eoughtonhill in Cumberland. The oxide of tin seems accidental, and is omitted in the corrected analyses. No. 5, a sulphate of copper from Mexico, and No. 6, the Krisuvigite of Forchhammer, a green mineral, forming considerable beds at Krisuvig in Iceland, seem chemically identical. Konigine of Levy, said to be rhombic, with o>P 105 ; and forming short prismatic crystals, of the combination ooP . OP . ooPoo . wPoo (n being a large number) ; cleavage, basal perfect ; H. = 2 ; trans- lucent ; lustre vitreous ; colour emerald or blackish-green ; consists, according to Wollaston, of copper protoxide and sulphuric acid, per- haps with water. It occurs in the Werchoturie Mountains in Siberia, and is probably identical with brochantite. 302. VIVIANITE, AUan, Dufrenoy ; Phosphate of Iron, Phillips: Blaueisenerde, Werner ; Blue Iron, Jameson j Eisenblau, Hausmann Fer phosphate, Hauy ; Dichromatic Euclase-Ha- loid, Mohs. Monoclinohedric, o>P 111 6', P 119 4', Poo 54 13'. The most common combination is ( aoPoo ). ccPoo . Poo , in prismatic crystals (fig. 203), but mostly small, and attached singly or in groups. Other crys- tals are like those of gypsum or fig. 205, p. 372. It also forms spherical Fig. 203. reniform masses, with a radiated columnar or fibrous tex- ture, or occurs massive, disseminated, and earthy. Cleav- age, clinodiagonal very perfect ; sectile, and in thin laminaa flexible; H. = 2 ; G. = 2*6 2-7. Translucent or in thin plates transparent ; lustre vitreous, cleavage faces bright pearly ; colour indigo-blue to blackish- green j by trans- Family. ,] VIVIANITE. 369 mitted light, olive-green along the axis andorthodiagonal, dark Berlin- blue along the clinodiagonal; streak bluish-white, but soon becomes blue on exposure ; the earthy variety is white in the beds but also changes to blue in the air ; the dry crashed powder is liver-brown. In the closed tube yields much water, intumesces, and becomes spot- ted with grey and red ; B.B. on charcoal becomes red, and then fuses to a grey, shining, magnetic granule. Easily soluble in hydrochloric or nitric acid ; becomes black in warm solution of potash. Analyses. Phospho- ric acid. Iron prot. Iron perox. Watr. Total. 1 26-4 41-0 31-0 98-4 Vogel, Bodenmais. 2 31-18 41-23 ... 27-48 99-88 Stromeyer, St Agnes, Cornwall. 3 26-90 42-10 28-50 97-50 Dufre'noy, Isle of France. 4 32-0 47-5 20-0 99-5 Klaproth, Eckartsberga. 5 6 30-32 23-1 43-77 43-0 25-OOa 32-46 99-82 99-4 Brandes, Hillentrup, Lippe. Berthier, Alleyras. 7 27-3 56-0 16-5 99-8 Do. Anglar. 8 26-06 46-31 27-14 99-51 Thomson, New Jersey. 9 24-95 48-79 26-26 100 Segeth, Kertsch, Crimea. 10 28-40 33-91 12 : 06 Rammelsberg, New Jersey. 11 . _, 33-98 12-06 27-49 Do. Do. 12 29-01 35-(>5 11-60 Do. Bodenmais. 13 28-60 34-52 11-91 27-49 102-52 MeanofNos. 10, 11, 12. 'a) + 0-70 alumina, 0-03 silica ; (&) + 0'6 alumina, 0-3 manganese peroxide. The earlier analyses are imperfect, from the uncertain methods of separating the iron from the phosphoric acid, and from not distin- guishing the two oxides of iron. Nos. 1, 2, 3 are the crystallized vivianite ; 4, 5, 6, the earthy or blue iron. No. 7 is the anglarite from the Haute Vienne, 9 per cent, peroxide of manganese being re- jected as accidental. No. 8 is the Mullicite from the Mullica Hills, 7 - 9 per cent, quartz being also rejected. In a mineral from the same locality, Vanuxem found nearly the same proportions as above. Nos. 10, 11 are also the mullicite, and No. 12 a crystallized variety from Bodenmais. According to Kammelsberg, the original colourless vivianite is a hy- drous phosphate of iron protoxide (isomorphous with erythrine), or Fe 3 *j>" + 8 H = 42 iron protoxide, 29 phosphoric acid, and 29 water. But on exposure 2 atoms of this salt exchange half the water for 3 atoms oxygen, when it acquires a blue colour, with the composition 6 (Fe 3 ''+ 8 H) + (re 3 * 2 + 8 H), with 29 '10 phosphoric acid, 33-00 iron protoxide, 12-22 iron peroxide, and 25-68 water. Transparent, indigo-coloured, crystals, sometimes an inch in dia- meter and two inches long, occur with iron and copper pyrites in the tin and copper veins at St Agnes in Cornwall ; other fine varieties at Bodenmais in beds of iron ore in gneiss ; in the auriferous veins at Vorospatak in Siebenburg, where it was first found, and at Allentown 370 DUFRENITE. [Copper-Salts and Imleytown in new Jersey. At Kertsch in the Crimea and in New Jersey, the fibrous variety fills the interior of fossil shells. In the Isle of France it occurs in lava, and also in the volcanic rocks of Sicily and Auvergne. The earthy varieties are very common, as in Cornwall, Styria, North America, Greenland, and New Zealand. It is often imbedded in clay, and in Northern Germany, Sweden, Nor- way, and the Zetland Isles, in peat mosses with iron ore, sometimes forming a blue crust on the dried peats, which in East Friesland are then thought of better quality. At Ballagh in the Isle of Man it incrust- ed fossil horns of the elk and deer, and it also occurred on the head of the rhinoceros preserved in the ice near the Wilui River in Siberia. It seems frequently a recent formation from putrid animal matter, large quantities having been found under some old slaughter houses at the foot of the Castle Eock in Edinburgh. It is sometimes used as a pigment. 303. DUFRENITE, Brougniart ; Griineisenstein, Mohs ; Green Iron Earth, Allan. Macrocrystalline, but probably rhombic with ooP == 123. Sphe- rical, botryoidal, reniform masses, with a radiated fibrous texture and drusy surface. Cleavage probably brachy diagonal ; very brittle. H. =3 3*5 ; G. = 3*3 3 '4. Translucent on the edges, or opaque ; shining or dull ; colour dirty or dark leek-green, pistacio or blackish- green. Streak siskin-green. Yields water in the closed tube. B.B. fuses readily to a porous, black, non-magnetic globule. Soluble in hydrochloric acid. Chem. com. 2 p'e 2 *P' + 5 H, or 63 iron perox- ide, 28 phosphoric acid, and 9 water. Analyses. ! 1 Phosphoric , 1 acid. Iron perox. Manganese perox. Water. Total. ! 1 2772 , 2 | 27-85 63-45 56-20 676 8-56 9-29 9973 100 Karsten, Siegen. Vauquelin, Haute Vienne. Green iron ores are found in many mines, as fibrous varieties in the Westerwald, at Hirschberg in Reuss, and Limoges in France ; the earthy in veins in the older rocks, and with limonite ores, as at Elbingerode in the Harz, in Saxony, Bavaria, and Hungary. Many of them seem merely mixtures, often of limonite, the earthy varieties of which frequently contain phosphoric acid. In No. 2 part of the iron is replaced by manganese peroxide, and it has been named alluaudite, but is not distinct. Family.] URANITE CHALCOLITE. 371 304. URANITE, Jameson, Phillips; Lime Uranite, Naumann ; Uran-mica, Uranglimmer, Werner ; Urane oxyde", Hauy ; Pyramidal Euchlore Malachite, Mohs. Tetragonal ; P 143. The crystals almost always tabular, through predominance of OP, and bounded on the sides by coP, P (fig 204) Fig. 204. or occasionally by other forms, are attached singly or united in small druses. Cleavage, basal very perfect; sectile; H. = 1 2 ; G. = 3 3'2. Translucent ; pearly on OP ; colour siskin-green to sulphur-yellow. Streak yellow. In the closed tube yields water and becomes yellow ; B.B. on charcoal fuses to a black mass with semi- crystalline surface ; with soda forms a yellow infusible slag. In nitric acid forms a yellow solution. Chem. com. essentially c'a 2 T + ir 4 "i" + 16 H, with 15 -5 phosphoric acid, 62'6 uranium peroxide, 6'21ime, and 15'7 water. Analyses. Phosph. acid. Uran. per ox. Lime. Ba- ryta. Tin oxide. Watr. Total. 2 15-20 14-5 6173 55-0 5-88 46 1-57 0-06a ...b 15-48 21-0 100-12 98-1 Berzelius, Autun. Laugier, Do. (a) + 0-20 magnesia and manganese protoxide ; (6) + 3'0 silica and iron peroxide. Uranite occurs, though rarely, in veins and beds with various ores, as at Johann-Georgeiistadt, and Eibenstock in Saxony, and of great beauty in granite at St Symphorien near Autun, and St Yrieux near Limoges in France. Also at Chesterfield in Massachusetts, and on Wolf island in lake Onega. 305. CHALCOLITE, Werner, Phillips ; Copperuranite, Kupfeniranite, Naumann. Tetragonal and isomorphous with uranite ; but the crystals are more acute in the edges. Cleavage, basal very perfect. Kather brittle ; H. = 2 2*5 ; Gr. = 3'5 3'6. Translucent ; pearly on OP. Colour grass to emerald or verdigris -green. Streak apple-green. B.B. acts like uranite ; but on charcoal with soda yields a grain of copper, and with salt of phosphorus and a little tin also shows re- action for copper. Moistened with hydrochloric acid, it colours the flame blue. In nitric acid forms a yellowish-green solution. Boiled in solution of soda it becomes brown. Chem. com. cu z T + ir' 4 *" -4- 16 H = 15-2 phosphoric acid, 61'1 uranium peroxide, 8'4 copper protoxide, and 15'3 water. Analyses, next page. In chemical composition this mineral only differs from uranite in containing copper protoxide instead of lime. If we consider these as S72 ERYTHRINE. [Copper -Salts Phos- phoric acid. Ura- nium, perox. Copper protox. Watr. Total. 1 2 74-1 16-0 1 60-0 8-3 9-0 15-4 14-5 97-8 99-5 Gregor, Cornwall. R. Phillips, Do. 3 15-57 61-39 8-44 15-05 100-45 Berzelius, Do. isomorphous with the uranium peroxide, the formula for both mine- rals may be given as [c a (cu) + u 2 ] 'P' + 8 H. Chalcolite occurs in veins in the crystalline schists or in granite, as at Johann-Georgenstadt, Eibenstock, and Schneeberg in Saxony ; Mi- chaelsberg in Bohemia ; Bodenmais in Bavaria ; near Baltimore in North America ; and in fine varieties near Redruth and St Austle in Cornwall. 306. ERYTHRINE, Beudant ; COBALT-BLOOM, Phillips ; Kobalt- bliithe, Hausmann ; Rother Erdkobold, Werner ; Cobalt ar- seniate, Hauy ; Diatomous Euclase-Haloid, Mohs. Monoclinohedric ; usual combination (ooPoo) (P) . ooPco (T) . Poo (Jf), forming rectangular prisms, terminated by an oblique plane (M) (like fig. 203 above, with M : T = 55 9') ; o>P3 (A) = 130 10', and P (7) 118 23', are often added (fig. 205). Cleavage, Fig. 205. clinodiagonal (P) very perfect. Eather sectile, in thin lamina} slightly flexible. H. = 2-5 ; G. = 2'9 3. Translucent ; lustre vitreous, but pearly on the cleavage planes ; colour crimson, or peach- blossom red, rarely pearl-grey, or dirty-green when decomposed. In the closed tube it yields water and becomes blue ; or, when it contains iron, green and brown. B.B. on charcoal in the inner flame fuses, emitting arsenical fumes, to a grey globule of arsenite of cobalt ; colours borax blue. It is easily soluble in acids ; and when digest- ed in solution of potash becomes black. Chem. com. according to Kersten, do 3 As' + 86, with 24 water, 38*5 ar- senic acid, and 37-5 cobalt protoxide, part of the latter being often replaced by lime or the protoxides of iron and nickel. Analyses, next page. Erythrine occurs in veins or beds with other cobalt ores, the crys- tallized or foliated variety especially at Schneeberg and Annaberg in. the Erzgebirge. The earthy is more common at the above and other places in Saxony, in Bohemia, Thuringia, the Harz, St Jean in the Family.'] NICKELINE. 373 Arsenic acid. Cobalt protox. Nickel protox. Iron prot. Lime. Water. Arse- nious acid. Total. 1 37 39 22 98 Bucholz, Riechelsdorf. 2 40-0 3 38-43 4 38-30 20-5 36-52 33-42 9-2 trace 6\a 1-01 4-01 24-5 24-10 24-08 !!! 100-3 100-6 99-81 Laugier, Allemont. Kersten, Schneeberg. Do. Do. G. = 2.912. 5 38-10 29-19 8-00 23-90 99-19 Do. Do. 6 19-10 16-60 trace 2-10 trace 11-90 51-00 100-70 Do. Do. 7 20-00 18-30 trace trace 12-13 48-10 93-53 Do. Annaberg. (a) Peroxide. Pyrenees, and Modum in Norway. It is also found in Cornwall, in the lead mines of Alston in Cumberland, at Alva in Stirlingshire, and Tyndrum in Perthshire in Scotland. It is used in preparing blue colours. The Kobalfbeschlag, or Earthy-encrasting-cobalt, which forms peach-blossom or rose-red reniform or spheroidal masses, is, according to Kersten (Nos. 6, 7), a mixture of erythrine with arsenious acid, which is extracted by hot water. Lavendulan of Breithaupt, forms thin reniform crusts of a lavender- blue colour, translucent, and resinous or vitreous. H. = 2-5 3 ; G. = 2'95 3*1. In the closed tube it yields water. B.B. fuses very easily, colouring the outer flame blue ; on charcoal emits odours of arsenic. According to Plattner, it consists of arsenic acid, prot- oxides of cobalt, nickel and copper, and water. It occurs very rarely in one of the mines at Annaberg. 307, NICKELINE, Beudant ; Nickel-ochre, Phillips ; Nickel-green, Dana ; Nickelbliithe, Hausmann ; Nikkelokker, Werner ; Nickel arseniate, Hauy. Microcvystalline (triclinohedric ? Hausmann) ; it occurs in short capillary crystals and flaky efflorescences ; also massive and disse- minated. Texture earthy, rather sectile ; H. = 2 2*5 ; G. = 3 8'1. Lustre dull or glistening. Colour apple-green or greenish- white ; streak greenish-white and shining. In closed tube yields water. B.B. on charcoal emits arsenical vapours, and fuses with reaction for nickel. Easily soluble in acids. Chem. com. NJ 8 As' + 8 H, with 38'4 arsenic acid, 37'6 nickel protoxide, and 24 water. Analyses, next page. This mineral seems a recent production arising in the decomposi- tion of various ores containing arsenic and nickel. It is found in many mines, as at Andreasberg in the Harz, Annaberg in Saxony, Saalfeld in Thuringia, Joachimsthal in Bohemia, and the Leadhills 374 CERUSSITE. {Lead-Salts 1 2 3 4 5 Ar- senic acid. Sul- phuric acid. Nickel oxide. Co- balt oxide. Iron prot oxide. Watr. Total. 36-97 36-8 38.30 38-90 37-21 0-23 : 52c 37'35a 36-2 36-20 35-00 36-10 2 : 5 1-53 trace 1-136 trace 2-21 1-10 24-32 25-5 23-91 24-02 23-92 100 100 9994 100-13 98-85 Stromeyer, Riechelsdorf. Berthier, Allemont, Dauphind. Kersten, Schneeberg. Do. Do. Do. Do. (a) With cobalt protoxide; (6) peroxide; (c) arsenious acid. in Scotland. At Riechelsdorf in Hessia it is used in preparing blue colours. III. FAMILY. LEAD-SALTS. 308. CERUSSITE, Haidinger ; Cerusse, Beudant ; Carbonate of Lead, Phillips ; Lead Spar, Jameson ; Weissbleierz, Werner ; Plomb carbonate, Hauy ; Diprismatic Lead Baryte, Mohs. Rhombic ; isomorphous with arragonite and nitre ; o>P (M) 117 14', Poo (P) 108 13', 2Poo (w) 69 18'. Other important simple forms are OP, P 0), P> 0), 4Poo , ooPoo (7), oo P3 (e) and some of the most common combinations P . 2P , P . ooPoo . coP, Poo . 2Pco . 4 POO . ooPoo . P . oo P (figs. 206, 207). The second figure, from Mohs, is placed in an opposite position from that adopted above after Naumann. The crystals appear partly pyramidal, partly horizontal, Fig. 206. Fig. 207. Fig. 208. or seldom vertical, prismatic, partly tabular, the brachydoms (w) ho- rizontally striated. Macles are very common combined by a plane of ooP, and either merely in -contact or intersecting. Sometimes three Family.'] CERUSSITE. 375 crystals are combined in a stellated group (fig. 208). The crystals are attached singly or united in druses, or form diverging and plu- mose groups. It also occurs fine granular or earthy. Cleavage, prismatic along ooP, also brachvdomatlc along 2P , both rather distinct. Fracture conchoidal ; brittle and easily frangible ; H. = 3 3'5 ; G. = 6'4 6*6 (earthy varieties only 5 - 4). Transparent or translucent ; lustre adamantine or resinous ; colourless and often white, but also grey, yellow, brown, black, rarely green, blue, or red. Streak white. B.B. decrepitates violently, becomes yellow, loses its carbonic acid, and acts like protoxide of lead. Wholly soluble with effervescence in nitric acid ; and also in solution of potash. Chem. com. pb c , with 83*6 protoxide of lead and 16*4 carbonic acid. Analyses. Lead prot. Carb. acid. Alumina and iron peroxide. Carbon. Total. 2 3 4 5 82 79 83-51 84-5 73-50 ]6 18 16-49 15-5 15-00 2 2 : 66 2" 8 : 00a 100 99 100 100 99-16 Klaproth, Leadhills. Lampadius (dark variety, Bleischwartze). Bergemann, Griesberg, Eifel. John, Nertschinsk (transparent). Do. Do. (translucent). (a) = silica. Thomson found the cerussite from Leadhills to be pure carbonate of lead with a mere trace of water. A variety from Monte Poni near Iglesias in Sardinia, with Gr. = 5*9, examined by Kersten, contained 92'10 carbonate of lead and 7*02 carbonate of zinc oxide. In another from the Charente department, Berthier found ^ per cent, car- bonate of silver ; and some Harz specimens also contain silver. The red earthy lead ore (Bleierde) from Kail in the Eifel seems a mere mixture ; and contains according to Bergemann 94*23 carbonate of lead, 2'57 water, 1-07 quartz, 2-2 peroxide of iron and alumina. Cerussite is a very common ore of lead occurring especially in beds or veins with galena. It is most abundant in the higher parts of the reins where the galena has begun to decompose, and is probably pro- duced, as Ilausmann suggests, by the sulphuric acid, then set free, act- ing on calc-spar, whose carbonic acid combines with the protoxide of lead. The more remarkable varieties occur at Przibram, Mies, and Bleistadt in Bohemia, Bleiberg in Carinthia, Rezbanya in Hungary, Zschopau and Johanngeorgenstadt in Saxony, Zellerfeld, Tanne, Andreasberg and Klausthal in the Harz ; in England in Devonshire and Cornwall, especially at the St Minver's mine in snow-white crys- tals of such extreme delicacy as almost to preclude the possibility of transport ; also at Alston Moor and Keswick ; in Scotland at Lead- 376 ANGLESITE. ^Lead-Salts hills and Wanlockhead, where stalactitic and stellated varieties are common. Fine varieties likewise occur in France, Tyrol, Siberia (Nertschinsk), the United States (Wythe County in Virginia, David- son's County in N. Carolina), and other places. The earthy lead- spar, as it is called, is common in most of the above localities, and also in Poland and Silesia ; and opaque pseudomorphs in the form of sulphate of lead occur at Leadhills. Where abundant this mineral is used as an ore of lead. 309. ANGLESITE, Beudant ; Sulphate of Lead, Phillips ; Plomb sulphate, Hauy ; Bleivitriol, Hausmann ; Vitriolbleieiz, Wer- ner ; Prismatic Lead Baryte, Mohs. Rhombic, P, Poo . ooP, too . OP, with others in which P and f P| more or less prevail. The crystals (fig. 209) sometimes short prismatic, at other times pyramidal, or tabular from OP, are Fig. 209. usua lly small, and attached singly or combined in druses. Cleavage, prismatic along o>P and basal, but neither very perfect. Fracture conchoidal ; very brittle ; H. = 3 ; GL == 6 -2 6 '3. Transparent or translucent ; lustre adamantine or resinous ; colourless and white, but occa- sionally coloured yellow, grey, brown, or blue ; streak white. B.B. in the closed tube decrepitates ; on charcoal fuses in the oxidating flame to a clear bead, which becomes milk- white when cold ; in the reducing flame yields lead ; with soda and silica shows the reaction for sulphur ; very difficultly soluble in acids, but wholly in solution of potash. Chem. com. pb'sY with 78*7 lead protoxide and 26 -3 sulphuric acid. Analyses. Lead protox Sulph. acid. Iron perox. Mang. perox. Watr. Total. ! j 1 2 3 71-0 70-50 72-47 24-8 25-75 26-09 1-0 : 09a ... i 2-0 ... ! 2-25 0-676 j 0-12 98-8 98-50 99-35 Klaproth, Anglesea. Do. Wanlockhead. , Stromeyef , Zellerfeld. j (a) Hydrous peroxide; (6) with trace of alumina + 0-51 silica. This mineral occurs with other lead ores principally in the older rocks. Fine varieties are found at Pary's Mine in Anglesea and in Cornwall, also at Zellerfeld, Clausthal, and Tanne in the Harz, at Ba- denweiler in Baden, in Siegen, Silesia, and other parts of Germany ; Southampton in Massachusets, Rossie in New York, and the Missouri mines in North America, also furnish good specimens. At Leadhills Family.] LEADHILLITE. 377 and Wanlockhead transparent tabular crystals some inches in diame- ter are common, and it also occurs in the interior or on the surface of cubical crystals of galena, from whose decomposition it is probably derived. Thomson, in a specimen from Wanlockhead, found only the pure sulphate of lesfd with a trace of water. The compact varie- ties or Bleiglas of the Germans are common at Alston Moor in Cum- berland, in Andalusia in Spain, and in Siberia. John found a blue variety from Linares in, Spain, coloured by copper ; and 100 Ibs. of that from Zellerfeld in the Harz yielded on cupellation f ounce (loth), and the same quantity of English anglesite ^ ounce of silver. 310. LEADHILLITE, Beudant ; Sulphato-tri-carbonate of Lead, Brooke, Phillips ; Bleisulphotricarbonat, Rammelsberg ; Axo- tomous Lead Baryte, Mohs. Monoclinohedric, C = 89 31', ooP 59 40', P 72 10', P 72 36', 2P (inclined to OP at 111 11'), 2Poo (toOP112 0'), and many other forms. The simplest combinations are OP . ooP . ooPoo (fig. 210), and OP . P . P . ooP . Poo . ooPoo ; but others far more com- F'ff 210 P^ ex occur ' an ^ often resemble hexagonal forms. The ' ' crystals are mostly tabular ; macles, especially of three Pr -rn crystals, occur united by a face of ooP3. These three- ^ * fold macles closely resemble a rhombohedric combination, but may be distinguished by their base being divided into three planes inclined to each other at 179 10'. It also forms foliated ag- gregates. Cleavage, basal very perfect. Slightly brittle. H. = 2-5; G. = 6'2 6'4 (6'0, Thomson). Transparent or translucent ; lustre resinous, or adamantine-pearly on OP ; colour yellowish-white, in- clining to grey, green, yellow, or brown. B.B. on charcoal intumesces, and becomes yellow, but again white when cold, and is easily reduced to metallic lead. Soluble with effervescence in nitric acid, leaving sulphate of lead. Chem. com. 3 pb c + Pb 's' t with 72'6 of the car- bonate and 27'4 of the sulphate of lead. Analyses. Sulphate Carbonate of lead. of lead. 1. 27'5 72-5 = 100 Brooke, Leadhills. 2. 28-7 71-0 = 99-7 Berzelius, Do. 3. 27-3 72-7 = 100 Stromeyer, Do. 4. 27-43 72.57 = 100 Thomson, Do. This mineral occurs at Leadhills in Scotland, in crystals an inch or less in diameter. The pearly lustre on OP is one of its most cha- racteristic marks. It is also said to occur in Grenada in Spain, and on the Greek island of Serpho in a bed of limonite in mica slate. li 578 LANARKITE CALEDONITE. [Lead-Salts 811. LANARKITE, Beudant; Sulphate-carbonate of Lead, Phillips ; Bleisulphocarbonat, Rammelsberg ; Prismatoidal Lead Baryte, Mohs. Monoclinohedric ; usual combination OP . Poo . ooP (with OP : Poo" 120 45') ; the crystals, lengthened prismatically along the or- thodiagonal, are indistinct. Cleavage, basal very perfect, hemido- matic along Poo imperfect ; sectile, and in thin laminae flexible. Very easily frangible (Breithaupt). H. = 2 2-5 ; G. =* 6-8 7 (Brooke), (6'3197, Thomson). Transparent ; lustre resinous or adamantine, on OP pearly ; colour greenish or yellowish-white, in- clining to grey. Streak white. B.B. on charcoal fuses to a white globule containing some metallic lead. Partially soluble in nitric acid with effervescence. Chem. com. pb *s* + pb c , vdth 53*15 sulphate and 46*85 carbonate of lead. Brooke found 53-1 sulphate, 46 '9 car- bonate ; Thomson, 53'96 sulphate and 46'04 carbonate of lead. The only certain locality is the Leadhills in Scotland. A compact variety is said to occur in Siberia ; and both this and the former species are reported to occur at Giepenbach near Tanne in the Harz. 312. CALEDONITE, Beudant; Cupreous Sulphato-Carbonate of Lead, Brooke, Phillips ; Paratomous Lead-Baryte, Mohs. Rhombic Poo 95, ooP 109, usual combination ooPoo , ooPoo. Poo (fig. 211) ; the crystals long prismatic, large and distinct ; also acicular, and grouped in radiating tufts. Cleavage, domatic along Fig. 211. Poo , brachydiagonal and macrodiagonal all imperfect ; H. = 2*5 3 ; G. = 6'4. Transparent or translucent ; lustre resinous ; colour verdigris to mountain -green ; streak greenish -white. B.B. on charcoal easily reduced to lead. Soluble in nitric acid, leaving sulphate of lead. The solution is greenish, and shows reaction for lead and copper. Chem. com., according to von Kobell, 3 pb "s" + 2 pb c + cu c, but Thomson thinks that the copper does not form a carbonate. Analyses. 1 Sulph. of lead. 1 55'8 2 j 52-88 Carbon, of lead. Copper protox. Watr, &c. Total. 32-8 31-91 11 -4a 13-37 1 : 84 100 100 Brooke, Leadhills (G. = 6'4 nearly). Thomson, Do. (G. = 5'0). (a) Carbonate. Found at Leadhills, though veiy rarely, and at first taken for ma- lachite. It is also said to occur near Tanne in the Harz with lanarkite and leadhillite. Family.] LINARITE P HOSGENITE. 379 313. LINARITE, Brooke ; Cupreous Sulphate of Lead, Phillips ; Bleilasur, Breilhaupt ; Diplogene Lasur-Malachite, Mohs. Monoclinohedric, ooP 61 0', Poo 77 15', Poo 74 25', C = 84 15'. The crystals, generally prismatic in the direction of the ortho- diagonal, are formed predominantly by ooPoo . OP, and the above or other hemidomes, and bounded by ( coPoo ) and oeP. Macles united by ooPoo . Cleavage, orthodiagonal very perfect, and hemidomatic along Poo less so. Fracture conchoidal. H. = 2-5 3 ; G. = 5'3 5 '45. Translucent ; lustre adamantine ; colour azure -blue ; streak pale-blue. Chem. com. pb s'+ cu H = 75-7 sulphate of lead, 19*8 copper protoxide, and 4 '5 water. Analyses. Sulph. of lead. Copper protox. Watr. Total. 1 2 75-4 74-8 18'0 19-7 4-7 5-5 98-1 100 Brooke, Wanlockhead. Thomson, Do. (G.= 5'2137). This mineral occurs in cavities with some of the previous species at Leadhills, but is rare. It is also said to occur at Linares in Spain, and perhaps in Cumberland. 314. PHOSGENITE, Breithaupt; Corneous Lead, Jameson; Murio- carbonate of Lead, Phillips ; Plomb chloro-carbonate", Dufre- noy ; Hornblei, Hausmann ; Orthotomous Lead Baryte, Mohs. Tetragonal, P 94 38'. The crystals usually formed of coP, OP, with oo Poo , and subordinate faces of P or 2Poo , are prismatic and small. Cleavage, prismatic along ooP rather perfect. Fracture conchoidal. H. = 2 -5 3 ; G. 6 6-2. Transparent or translu- cent ; lustre resinous adamantine ; colour white, yellowish, greenish, or greyish-white, to wine-yellow, asparagus-green, or grey. B.B. fuses easily in the outer flame to an opaque yellow globule, becoming citron-yellow or white with a crystalline surface on cooling. In the inner flame evolves acid vapours, and is reduced to lead. Soluble with effervescence in nitric acid. Chem. com. Pb Cl -f- pb c , with 51 chloride and 49 carbonate of lead, or 79-22 protoxide of lead, 12-93 hydrochloric acid, and 7-85 carbonic acid. Klaproth found in a specimen from Matlock, 85-5 protoxide of lead, 6'0 carbonic acid, and 8-5 muriatic acid (= 100) ; but, as Berzelius observed, the ana- lysis was wrong calculated, and the muriatic acid should be 14-0 (total 105-5) (Rammelsberg). This is a very rare mineral, being chiefly found at Matlock in Derbyshire, with cerussite and heavy spar. Badenweiler in Baden, Southampton in Massachusets, and Vesuvius, are other localities where it is reported to occur. 380 MENDIPITE COTUNNITE. [Lead- Salts 315. MENDIPITE, Breithaupt ; Muriate of Lead, Phillips ; Plomb chlorure, Dufrenoy ; Berzelite, Levy ; Cerasite, Dana ; Pe- ritomous Lead-Baryte, Mohs. Rhombic, but chiefly massive in crystalline or thin-columnar ag- gregates. Cleavage, prismatic along ooP 102 27', highly perfect. Fracture conchoidal or uneven. H. = 2*5 3 ; G. = 7'0 7-1. Translucent ; lustre adamantine-pearly on the cleavage faces ; colour yellowish-white to straw-yellow and pale red ; streak white. B.B. decrepitates, fuses easily, and becomes more yellow. On charcoal yields lead and acid vapours. With salt of phosphorus and copper oxide colours the flame blue. Easily soluble in nitric acid. Chem. com. Pb Cl + 2 pb, or 40 chloride and 60 protoxide of lead = 85*8 lead, 9 '78 chlorine, and 4-42 oxygen. Analyses. 1 2 3 4 5 Lead protox. Muriatic acid. Carbonic acid. Water. Silica. Total. 90-20 90-13 76'93 6-54 6-84 8-46a 2-63 1-03 15-90& 0-63 0-54 0-63 1 : 46 100 100 101-82 100 100 Berzelius, Churchill. Do. No. 1 corrected, Rammelsberg. No. 1 by Rammelsberg. Schnabel, Brilon. Lead. Chlorine. Oxygen. 85-53 85-69 10-15 9-87 4-32 4-44 (a) Chlorine ; (&) carbonate of lead. No. 3 is corrected according to the new atomic numbers, the lead being somewhat deficient from the method of its determination. It is found at Churchill in the Mendip hills in Somersetshire, on black earthy manganese, and in the Kunibert mine near Brilon in Westphalia. This rare mineral is said also to occur in Cornwall, at Caldbeck near Keswick, and on the lava of Vesuvius ; but the spe- cimens from the latter place* are very indistinct. 316. COTUNNITE, von Kobell; Cotunnia, Monticetti. Rhombic, ooP 118, in small acicular crystals and semifused masses. Transparent, lustre adamantine, colour white. Easily scratched with the knife. G. = 5*238. In closed tube fuses and then sublimes, the fused mass being yellow when warm. B.B. on charcoal fuses easily, colours the flame blue, volatilizes as a white vapour, forms a white ring, and leaves a very little metallic lead. Soluble in a large amount of water. Chem. com. Pb Cl, with 74 lead and 26 chlorine. Observed by Monticelli and Covelli in the crater of Vesuvius after the eruption of 1822. Family.'] PTROMORPHITE. 381 317. PYROMORPHITE, Hausmann ; Phosphate of lead, Phillips ; Griin and Braunbleierz, Werner in part ; Plomb phosphate, ffauy ; Rhombohedric Lead-baryte, Mohs. Hexagonal, P 80 44'. Usual combination, ooP. OP, often with Fig. 212. ooP2, rarely with P or other pyramids (fig. 212), forming prismatic crystals occasionally thicker in the middle, or spindle-shaped. The basis, OP, is often rough or hollow. The crystals are generally united in druses, or it forms reniform, botryoidal, and massive aggregates. Cleavage, pyramidal along P very imperfect ; prismatic along ooP in traces. Fracture conchoidal or uneven. H. = 3'5 4 ; G. = 6*9 7. Translucent ; lustre resinous or partly vitreous ; co- lourless, but generally coloured grass, pistacio, olive, or siskin-green, and clove or hair-brown. B.B. fuses easily, and on cooling forms, with a transitory ignition, a polyhedric crystalline granule. With boracic acid and iron wire, forms phosphate of iron and lead, the latter remaining fluid after the former has become solid. Yields lead with soda. Soluble in nitric acid and in solution of potash. Chem. com. 3p b 3 V + Pb Cl, with 89-7 phosphate of protoxide of lead and 10*3 chloride of lead, but the phosphoric acid is often partly replaced by arsenic acid, the protoxide of lead by lime, and the chloride of lead by fluoride of calcium. Analyses. Phos- phate of lead. Chlo- ride of lead. Arseni- ate of lead. Phos- phate of lime. Fluor- ide of calcium Iron prot- oxide. Total. 1 89-94 10-05 99-99 Wohler, Zschopau, green. 2 80 '37 10-09 9-01 ( 99-47 Do. Do. white. 3 88-16 9-91 trace 98-07 Do. Leadhills, orange-red. 4 77-02 10-84 11-05 1*09 100 Kersten, Freiberg, brown. 5 81-65 10-64 7-46 0-25 100 Do. Mies, botryoidal. 6 89-27 966 0-85 0-22 100 Do. Do. crystallized. 7 89-17 9-92 0-77 0-14 100 Do. Bleistadt, do. 8 89-11 10-07 0-68 0-13 ... 99-99 Do. England, do. 9 89-91 10-09 100 Do. Poullaouen, do. 10 89-93 10-07 100 Do. Do. massive. 11 88'42 10-25 1*33 100 Thomson, Leadhills. 12 92-55 13 87*38 7-45 10-23 : 86 : 07 077 100 99-31 Bergemann, Eifel, green. Lerch,Bleist. brown,G.6'843. 14 88-42 9-57 1-58 0-20 0'50a 100-27 Do. Do. do. do. (a) Phosphate. Pyromorphite generally occurs in veins, and almost constantly as- sociated with galena, and also with other lead ores, especially the ce- russite. It is most abundant in the upper parts of the veins, and, in some cases, seems a recent produce from the galena. In some veins, the latter forms the centre, followed by the pyromorphite, and this by crocoisite on the exterior. The finest varieties are found in the Bohemian mines of Przibram, 382 MIMETESITE. [Lead-Salts (green and yellow) ; Mies (green and brown) ; and Bleistadt (white and brown) ; and at Zschopau in Saxony ; less beautiful in the Breisgau, Clausthal in the Harz, Poullaouen in Brittany, and other parts of France, Beresow in Siberia, in Mexico, and other countries. It also occurs in Cornwall and various parts of England, at Wicklow in Ireland, and at the Leadhills in Scotland. At the latter it is found in hexagonal prisms, or more often in rosettes and cauliflower-like groups or crusts. No. 11 is a mean of analyses of five specimens, with G. = 6*5781 6-70016, none of them containing any phos- phate of lime. A light greenish-yellow specimen, with slaty texture, and G. = 5-366, contained 15 per cent, phosphate of lime ; another dark-green and botryoidal, G.. = 5*970, yielded 9 per cent. A va- riety of a beautiful orange- colour with no red in it, is also abundant at Wanlockhead, and contains 2 per cent, chromate of lead, but other- wise agrees with the green varieties, Thomson. In the yellowish- green pyromorphite from Beresow, G. Kose also found chrome both as the acid and oxide. Miesite and Polysphaerite of Breithaupt, Nos. 4, 5, are brown, reni- form or botryoidal varieties, containing more lime, and with a lower specific gravity (miesite, 6*4 ; polysphaerite, 5*9 6'1). The Nus- sierite, from Nussiere, near Beaujeu, is a yellowish, greenish, or white mineral, G. = 5'04, very like the pyromorphite, and con- taining the same elements in somewhat different proportions. Bar- ruel's analysis gave 46*50 lead protoxide, 19 '80 phosphoric acid, 4*06 arsenic acid, 7*65 chloride of lead, 12'30 lime, 2-44 iron protoxide 7*20 silica (= 99*55). 318. MIMETESITE, Breithaupt; Arseniate of Lead,- Phillips ; Mi- metene, Dana; Griinbleierz, Werner; Plomb arseniate', Hauy; Brachytype Lead-Baryte, Mohs. Hexagonal ; P 83 47' ; usual combination coP . OP . P, or P . OP, sometimes also with o>P2, 2P, P. The crystals are short prismatic, tabular, or pyramidal, forming rosettes and other groups. Cleavage, pyramidal along P, rather distinct, prismatic along ooP, veiy imper- fect. Fracture conchoidal or uneven ; H. = 3*5 4*0 ; G. = 7*19 7*25. Translucent ; colourless, but usually coloured honey or wax-yellow, yellowish-green, or grey. B.B. on charcoal fusible, but less easily than pyromorphite, and yields a grain of lead with strong arsenious vapours. Fused in the forceps, it crystallizes on cooling. With the fluxes acts like lead protoxide. Soluble in nitric acid and solution of potash. Chem. com. 3 p'b 3 'A S + Pb Cl, with 90*7 arse- niate and 9*3 chloride of lime; but part of the arsenic acid occasion- ally replaced by phosphoric acid. Family.'] BLELNIEIUTE. 383 Kather rare, but occurs especially at Johann-Georgenstadt ; also at Zinnwald, Badenweiler, St Prix in France, Nertschinsk in Siberia, and massive and botryoidal in Mexico. Fine crystals are found in Wheal Alfred and WheaL Unity mines near Redruth in Cornwall, at Caldbeckfell in Cumberland, and Beeralston in Devonshire. The Kampylite of Breithaupt, forming orange-yellow, hexagonal prisms expanded in the middle, with G. = 6'8 6*9, has essentially the same composition with mimetesite, but contains phosphate of lime and traces of chromate of lead. It occurs at Alston in Cum- berland and at Badenweiler. HEDYPHANE of Breithaupt occurs in small crystalline masses with an imperfect cleavage along an hexagonal pyramid. Fracture con- choidal ; H. = 3'5 4 ; G. = 54 5*5. Translucent ; lustre resinous adamantine ; colour white. B.B. when the arseniate of lead predominates, the phosphate is not wholly reduced, but remains as a fused crystalline bead ; the occurrence of arsenic may be known from its odour when heated. Chem. com. (analysis No. 2) similar to the mimetesite, but a large part of the protoxide of lead replaced by lime. It occurs at Langbanshytta in Sweden. Analyses. Arse- niate of lead. Phos- phate of lead. Chlo- ride of lead. Arse- niate of lime. 'Phos- phate of lime. Total. 1 8274 2 60-10 7-50 9-60 10-29 12-98 15-51 99-84 98-88 Wohler, Johann-Georgenstadt. Kersten, Langbanshytta. No. 1 is mimetesite, No. 2 hedyphane ; in a variety of the former from Wheal Unity, Gregor found 69*76 lead protoxide, 2640 arsenic acid, and 1*58 muriatic acid. Pyromorphite and mimetesite may, in a more general point of view, be regarded as one species, and Weiss conjoins them under the name of Buntbleierz. Mohs formerly also united them, but in the last edition of the Anfangsgrunde they are again separated. 319. BLEINIERITE, N. ; Bleiniere, Hausmann ; Arseniate de plomb terreux, Beudant. Amorphous, in reniform spheroidal masses, often with a curved lamellar division; also occurs earthy, disseminated, or encrusting. H. = 4, G. = 3-933 (Karsten), 4'60 476 (Hermann). Opaque ; lustre dull resinous, or earthy ; colour grey or brown to brownish- red, yellow or yellowish-white, sometimes veined or clouded. Streak greyish or yellowish-white. In the closed tube it yields water and becomes darker. B.B. on charcoal is reduced to a grain of metal, which when ignited gives out antimony fumes and leaves lead. Some varieties evolve arsenious odours. Chem. com. pb 3 "s'b + 4n by 384 VAJSTADINITE. [Lead-Salts Hermann's analysis, which gave 61'83 protoxide of lead, 81*71 an- timonic acid, and 6-46 water (= 100). It was formerly analyzed by Bindheim, who overlooked the antimony, and by Pfaff, who found 33-10 protoxide of lead, 43-96 antimonious acid, 16-42 arsenic acid, 3*24 copper protoxide, 0'24 iron peroxide, 2-34 silica, 062 sulphuric acid, and 3 "32 of iron, manganese, and some unknown substance (= 103-23). This was evidently a mere mixture of various decom- posed ores. Hausmann finds that many bleinierites contain arsenic as well as antimonic acid, as is shown by their action B.B. This mineral seems a product of the decomposition of other lead ores. Its only certain locality is Nertschinsk in Siberia. 320. VANADINITE, v. Kobell; Vanadiate of Lead, Phillips : Vanadinbleierz, Mohs. Hexagonal, hitherto only ooP . OP, prismatic, small. Cleavage, not distinctly perceptible. H. = 3 ; G. = 6'8 7 -2. Opaque ; lustre resinous, but dull ; colour yellow and brown ; streak white. B.B. decrepitates violently, and on charcoal fuses to a globule, which emits sparks and is reduced to lead, colouring the support yellow. With salt of phosphorus it forms in the oxidating flame a glass reddish-yellow when warm, yellowish-green when cold ; in the reducing flame, a beautiful chrome-green glass (variety from Beresow, G. Rose). That from Wanlockhead fuses in the forceps, and retains its yellow colour when cold. On charcoal yields odour of arsenic (Johnston). Easily solu- luble in nitric acid. Chem. com. perhaps 3 pb 3 "v -I- Pb Cl. Ana- lyses. Lead oxide. Lead. Vana- dic acid. Chlo- rine. Zinc oxide. Cop- per prot. Watr. Iron perox. silica. Total. 1 2 66-33 63-73 7-06 6-62 23-43 1586 2-45a 2-27 6 : 35 2 : 96 3 : 80 0-16 99-44 101-58 B. D. Thomson. Damour. (a) Muriatic acid. In vanadinite from Zimapan in Mexico, Berzelius found 74*00 basal vanadiate of lead, 25'33 basal chloride of lead, 0'67 hydrous peroxide of iron, and a trace of arseniate of lead. No. 1 was said to have been found in Wicklow in Ireland, but Thomson thinks was more probably from Wanlockhead, where it occurs in light brownish-yellow hexa- gonal prisms. Other crystals of an orange colour seem to have rather a different composition. At Beresow near Katharinenburg in Siberia, it is found in the auriferous veins along with the pyromor- phite. The locality of No. 2 is unknown. It also occurs at Matlock in Derbyshire. Family.'] WULFENITE. 385 321. WULFENITE, Haidinger; Molybdate of Load, Phillips; Gelb- bleierz, Warner; Plomb molybdate', Hauy; Pyramidal Lead- Baryte, Molis. Tetragonal, P 131 35' (*31 30' 132, Brat.) ; the most common forms are OP (a), ^P (, P, P, ooP, |Poo , and Poo ; the crystals partly tabular (fig. 213), partly short prismatic or pyramidal, usually col- lected in druses. Cleavage, pyramidal along P rather perfect, basal imperfect. Fracture conchoidal to uneven ; rather brittle ; H = 3 ; Fig. 213. G. = 6-3 6*9. Semitraus- parent to translucent on the edges ; lustre resinous or ada- mantine ; colourless, but gene- rally coloured yellowish-grey, wax, honey, or orange-yellow. B.B. decrepitates violently ; on charcoal fuses and sinks into the support, leaving lead behind. Easily reduced with soda; readily soluble in salt of phosphorus, forming a glass of a green, or, with more assay, of a black colour. The powder is decomposed by warm nitric acid, throwing down yellowish -white nitrate of molybdena. In con- centrated hydrochloric acid forms a yellow solution, from which chlo- ride of lead separates. Also soluble in sulphuric acid and in solution of potash. Chem. com. p'b MO, with 60*9 protoxide of lead and 39*1 molybdic acid. Analyses. 2 3 4 5 6 Lead prot. Molvbd. acid. Iron perox. Lime. Silica. Total.| I 59-23 58-40 59-0 61-90 43-0 73-8 34-25 37-00 40-5 40-29 422 10-0 3-08 8*-5 1-7 6-3 : 28 37a 93-48 Klaproth, Bleistadt (cor. by Bam.) 9876. Hatchett, Do. 99-5 JGobell, Do. 102-19; Melling, Do. 100-0 Domeyko, Chili. 98-1 1 lioussingault, Paramo-Rico. (a) + 2-9 carbonic acid, 1-3 muriatic acid, 1-3 phosphoric acid, 1-2 chromic acid, and 2-2 In some varieties Rammelsberg observed vanadium, perhaps from a mixture of vanadiate of lead. The red crystals from Rezbanya contain, according to G. Rose, only a small amount of chrome, and in other respects agree with the Bleiberg variety. In No. 5 the iron peroxide is perhaps only a mixture, though the specimen was crystallized, and the lime may replace part of the lead protoxide. The variations in specific gravity and angular dimen- sions noticed by Breithaupt are probably also caused by lime. No. 6, which occurs in small yellowish -green concretions, G. 6'0, in a decayed syenite near Pamplona in South America, has been consider- ed a basal molybdate of lead, pb 3 MO ; but seems a mere mixture. Kk 386 SCIIEELITINE PLOMGOMME. [Lead-Salts It occurs in beds and veins in limestone at Bleiberg and other places in Carinthia, in Austria, the Tyrol, and Hungary. Also in Baden, Saxony, Dauphine", and in small amount in Massachusets and Phila- delphia, and at Zimapan, Mexico. 322. SCHEELITINE, Beudant ; Tungstate of lead, Phillips; Scheel- bleierz, Naumann ; Stolzit, Haidinger ; Dystomous Lead-Ba- ryt, Mohs. Tetragonal and pyramidal-hemihedric ; P 131 30'. It generally forms very acute pyramidal, almost spindle-shaped, crystals of the combination 2P . P . ooP ; rarely they are short prismatic. Most frequently they are small, indistinct, and combined in bud-like or spherical groups. Cleavage along P imperfect. H. = 3 ; G. = 7-9 8-1. Semitransparent or translucent ; lustre resinous ; coloured grey, brown, yellow, or green. B.B. fuses, stains the charcoal with oxide of lead, and on cooling forms a dark crystalline grain ; with salt of phosphorus in the oxidating flame gives a colourless, in the reducing flame a blue glass ; with soda yields beads of lead. Soluble in nitric acid, with a precipitate of yellow tungstic acid. Chem. com. p b w = 51-54 tungstic acid, and 48*46 protoxide of lead. Lampa- dius found 51*75 tungstic acid, and 48'25 lead protoxide. It is only found in druses with quartz and mica in the tin mines at Zinnwald in Bohemia ; and perhaps also at Bleiberg in Carinthia. The simi- larity of its crystallization to that of scheelite confirms the isomorphism of lime and protoxide of lead when in union with the same acid. 323. PLOMBGOMME, Laumont, Allan ; Hydrous Aluminate of Lead, Phillips; Plomb hydro-alumineux, Hauy ; Bleigum- mi, Mohs, fyc. Botryoidal, reniform, or stalactitic masses, with an apparent pris- matic cleavage (?). Fracture conch oidal and splintery. H. = 4 4-5 ; G. = 6*3 6 '4. Translucent ; lustre vitreous, inclining to resinous ; colour yellowish or greenish-white, to reddish-brown, often in stripes. In the closed tube yields water and decrepitates violently. B.B. on charcoal becomes opaque and white, intumesces, and partially fuses ; with soda it is reduced to lead, and with solution of cobalt becomes blue. Soluble in nitric acid. Chem. com. i>b 3 *i>* + 6 AI H 3 , by Damour's analysis, neglecting the chloride of lead, and adding the lime to the protoxide of lead, the iron peroxide to the alumina. Analyses, next page. In the older analyses the phosphoric acid was overlooked. It oc- curs with galena and other lead ores at Poullaouen in Brittany, and at NussieVe near Beaujeu. In general aspect it much resembles Family. J CROCOISITE. 387 Lead prot. Phosph. of Lead. Phos- phoric acid. Alu- mina. Watr. Mix- tures. Total. 9 ;; 4 40-14 37-51 35-10 10-0 7 ! 92 8-06 25-5 c 374)0 34-23 34-32 23-0 18-80 16-13 1870 38-Od 2-60 2-lla 2-27b 3-0 e 98-54 9777 9975 99-5 Berzelius, Huelgoet, G. 6'4. Dufre"noy, Nussie"re, G. 4-88. Damour, Huelgoet. Berthier, Carmeaux. (a) Silica ; (b) chloride of lead + 0-80 lime, 0-20 iron peroxide, and 0-30 sulphuric acid (c) with trace of arsenic acid ; (d) with organic matter ; (e) copper protoxide. gnm- arable. No. 4 is a recent sinter found in the mines near Car- meaux with arseniate of copper ; and, as Berzelius states, is essentially a hydrous phosphate of alumina, Jvi 4 'p' 3 , mixed with phosphate of lead, pb 3 ''p''. 324. CROCOISITE, v. Kobell; Krokoit, Breithaupt ; Chromate of lead, Phillips; Red-lead spar, Jameson; Rothbleierz, Werner; Plomb chi-ornate", Hauy; Hemiprismatic Lead-baryte, Mohs. Monoclinohedric ; C = 78, 3 , part of the lime being replaced by protoxides of manganese and iron. Damour's analysis gave 79-31 antimonious acid, 16'67 lime, 2'60 manganese protoxide, 1'20 iron protoxide, and 0*64 silica (= 100-42). It has been found in the manganese mines at St Marcel in Piedmont, and is named in honour of the celebrated crystallographer Rome de L'Isle. 334. SCHEELITE, v. Leonhard, Beudant; Tungsten, Scheele, Jame- son ; Tungstate of Lime, Phillips ; Scheelin calcaire, Hauy ; Schwerstein, Werner ; Pyramidal Scheel-Baryte, Mohs. Tetragonal and pyramidal-hemihedric, P 112 1', often alone. The usual combinations are P (P) . 2Poo (g) ; 2Poo . P . OP ; OP . P. The character of the crystals is mostly pyramidal (fig. 216), rarely ta- Fig. 216. bular, like fig. 213 above ; and they are at- tached singly or in groups and druses. Cleav- age, pyramidal along 2Pco 129 2' rather per- fect, along P and OP less perfect. Fracture conchoidal and uneven ; H.= 4 4'5 ; G.= 5-9 _ 6-2. Translucent ; lustre vitreous, in- clining to resinous on the fracture, to ada- mantine on the crystal faces and cleavage ; co- lourless, but usually coloured grey, yellow, or brown, rarely orange-yellow or green ; streak white. B.B. fuses difficultly to a translucent glass. With borax to a clear colourless bead, which, if not fully saturated, remains clear when cold, but if again slowly heated, be- Family.} SCHEELITE. 393 comes opaque and enamel-like ; if fully saturated it becomes milk- white, and crystalline immediately on cooling. With salt of phos- phorus forms a glass, which, in the oxidating flame, is clear and co- lourless, in the reducing ffame green when warm, blue when cold. Decomposed in hydrochloric or nitric acid, leaving tungstic acid; also in solution of potash, with precipitate of lime. Chem. com. when pure, ca w, with 80 '6 tungstic acid and 19'4 lime, but it generally con- tains silica and iron peroxide, or rarely copper protoxide when the mineral is green. Analyses. Lime. T 3" c Silica. Iron perox. Mang. perox. Total. 1 17-60 7775 3-00 98-35 Klaproth, Schlackenwald. 2 1870 75-25 1-50 1 : 25 0.75 97-45 Do. Pengilly, Cornwall. 3 19-40 80-42 ... 99-82 Berzelius, Westmanland. 4 19-06 78'00 2-00 ** ... 99-06 Brandes and Bucholz, Schlackenwald. 5 16-60 76-50 2-94 1-50 ...a 98-54 Do. and Do. Zinnwald. 6 19-36 76-05 2-54 1-03 0-31 99-29 Bowen, Huntington, Connecticut. 7 18-05 75-75 0*75 ...& 97-85 Domeyko, Coquimbo, Chili. 8 21-56 78-64 ... ... JIOO'20 Rammelsberg, Neudorf (G. = 6'03). & 18-88 78'41 ... ... * 97*94 Choubine, Katherinenburg (G. = 6'071 ). (a) + 1-10 alumina and lime; (6) -f 3-30 copper protoxide; (c) + 0-65 magnesia. In the tungsten (hystatic), G. = 5'97 5'99, from Zinnwald, Brei- thaupt finds hydrochloric and fluoric acids ; in that from Schlacken- wald (macrotype, G. = 6*2), from 2 3 per cent, of fluoric acid. This mineral occurs with wolfram, especially in veins of tin ore, sometimes in beds with gold or magnetic iron, also with galena and quartz. The finest crystals have been found in quartz at Caldbeck- fell near Keswick : at Zinnwald and Schlackenwald in Bohemia, and the above localities. It is also found in the gold mines of Schellga- den in Salzburg, and of Posing in Hungary ; in the copper mines of Llamuco in Chili (No. 7), of a green colour; and at Katherinenburg in Siberia. At the Monroe mines in Connecticut it has been used in preparing tungstic acid, which forms a very fine yellow pigment, su- perior to chrome-yellow ; but the mineral is too rare to be generally used. 394 MAGNETITE. [Oxidized Iron Ore TV. ORDER. OXIDIZED ORES. I. FAMILY. OXIDIZED IRON ORES. 335. MAGNETITE, Haidinger; Magnetic Iron, Allan; Oxidulated Iron, Phillips ; Magneteisenerz, Naumann ; Magneteisen, v. Leonhard; Fer Oxydule", Hauy ; Octahedral Iron ore, Mohs. Tesseral ; O and ooO are the most frequent and predominant forms ; also ooOco , 2O2, 2O, and others. Macles are common, united by a plane of O (fig. 217). The crystals occur imbedded or in druses. Generally it is found massive in granular or almost compact aggre- Fig. 217. gates ; often also in loose grains, forming magnetic sand. Cleavage, octahedral sometimes perfect, at other times in mere traces. Fracture conchoidal or uneven ; brittle ; H. = 5-5 6'5 ; G. = 4-9 5-2. Opaque ; lustre metallic, sometimes im- perfect ; colour iron-black, occasionally inclining to brown or grey ; highly mag- netic. B. B. becomes brown and non- magnetic, and fuses with extreme diffi- culty : powder soluble in hydrochloric acid. Chem. com. p e Pe, with 31-03 of the protoxide and 68*77 of the peroxide of iron, or 72-40 iron and 27-60 oxygen. Analyses. Iron perox. Iron prot. Mang. prot. Vein- stone. Total. 1 69 31 100 Berzelius, Sweden. 2 74-96 3 73-84 25-04 21-48 2-00 2 : 68a 100 100 v. Kobell, crystallized, Schwarzenstein. Do. foliated, Arendal. 4 69-95 29-53 0-256 0-15 99-88 Karsten, crystallized, Dannemora. 5 66-23 27-65 5-95 99-83 Do. massive, Thorsaker, Sweden. 6 69-40 28-25 l-85c 99-50 Do. granular, Gellivara, Lapland. 7 68-03 29-25 2-45 99-73 Do. massive, Arendal. 8 67-95 29-92 1-86 99-73 Do. cryst, Berggeishiibel, Saxony. 9 67-56 28-66 3-31& 99-53 Do. cryst., Tyrol. 10 68-40 30-88 99-28 Fuchs, crystallized. (a) Silica; (6) titanic iron; (c) specular iron. From his analyses of iron ore from Schwarzenstein in the Ziller- thal (No. 2 above, mean of three), v. Kobell deduces the formula Fe 3 FeS which gives 25-19 of the protoxide and 74-81 of the perox- ide. Hence there are either more than one variety of this ore, or, as Family.'] MAGNETITE. 395 is more probable, it is occasionally mixed with specular iron ore. Breithaupt regards the varieties with the formula Fe 3 p'e 4 , as distinct from the others, and says that they possess greater hardness and higher specific gravity. Some highly-magnetic varieties, especially from Siberia and the Harz, form natural magnets, possessing distinct polarity. Others only become polar after contact with magnets of sufficient power ; and some require to be touched before they will even attract iron filings. Magnetic iron occurs especially in igneous or metamorphic rocks, either in distinct crystals, or, as in many basalts, disseminated through the mass, when it frequently imparts magnetic properties to the rocks, especially to granite, serpentine, or basalt. It also forms beds in gneiss, in chlorite, mica, hornblende, and clay slates, in mar- ble, greenstone, and other rocks, but seldom appears in veins. The largest known masses occur in the northern parts of the globe, in Scandinavia, Lapland, Siberia, and North America. In Norway, Arendal is the most important locality ; in Sweden, Dannemora, Utoe, Norberg, Taberg ; in Lapland, Kurunavara and Gellivara ; in the Ural, Wissokaja Gora near Nischne-Tagilsk ; Blagodat near Kuschwinsk, and the Kaschkanar near Nischne-Turjinsk. Less ex- tensive masses occur in the Harz, in Saxony, Bohemia, Silesia, and Styria; and in Southern Europe, in Elba and Spain. It is also found in Mexico and Brazil. Beds of magnetic iron ore are known in several parts of Scotland ; but, from the distance from fuel and the abundance of other ores, have attracted little notice. Magnetite is the most important ore of iron in Norway, Sweden, and Russia. The quality of the iron is much affected by the asso- ciated minerals, of which pyrites and apatite are especially prejudicial. The Dannemora mines, wrought in an open quarry 150 feet broad and 500deep, furnish thefine Oeregrundiron, largely imported into England for the manufacture of steel. The fine quality is ascribed to the ores being mixed with calc-spar, which, with garnet, thallite, augite, and hornblende, is considered highly advantageous for their reduction, and the granular ores often require no other flux. The compact varieties, especially when mixed with quartz, are on the contrary very diffi- cultly fusible. This mineral often changes slowly into the oxyhydrate of iron. The fine octahedral crystals of specular iron, found in Brazil and the Ural, show that it may also, in certain circumstances, be converted into the peroxide. It is, on the other hand, sometimes formed during smelt- ing processes, especially where atmospheric air or aqueous vapour have come in contact with the hot iron. The latter seems particu- larly favourable to the formation of crystals. 396 CHROMITE FRANKLINITE. [Oxidized Iron Ore 336. CHROMITE, Haidinger ; Chromate of Iron, Phillips, Allan ; Chrom-Eisenstein, Werner; Fer chromate, Hauy ; Octahe- dral Chrome Ore, Mohs. Tesseral ; only in octahedrons. It generally occurs massive and granular. Cleavage, octahedral imperfect ; fracture imperfect con- choidal or uneven. H. = 5*5; G. = 4*4 4-5. Opaque; lustre semi-metallic or resinous ; colour iron or brownish-black ; streak yellowish to reddish-brown. Sometimes magnetic ; weak electric conductor. B.B. infusible alone, and remains unchanged, except that the non-magnetic varieties when ignited in the reducing flame become magnetic. In borax it is slowly soluble, forming a bead emerald- green when cold. Fused with nitre it forms a yellow solution in water, which shows reaction for chromic acid. Scarcely affected by acids. Chem. com. (p e , Mg) (cr, Ai)- Analyses. Iron | Chrome prot. I perox. Alu- mina. Mag- nesia. Silica. Total. i 1 2 3 37-0 36-0 25-66 54-08 36-00 1 39-01 21-5 9-02 13-00 5 : 36 5-0 483 10-60 99-5 98-95 99-11 Berthier, St Domingo, v. Kobell, Roraas, Norway. Seybert, Baltimore. 4 35-14! 51-56 972 ...a 2-90 99-32 Do. Chester, Pennsyl. a 20-13 ! 60-04 11-85 7-45 ... 99-47 Abich, Baltimore, cryst. 6 18-97 i 44-91 13-85 9-96 0-83 98-25 Do. Do. massive. (a) Trace of protoxide of manganese. Chromite occurs generally in serpentine, or in crystalline limestone near this rock, either in veins, nests, or disseminated. It is found in Saxony, Silesia, Bohemia, and Styria (Kraubat) ; at Gassin in the Var department in France, where it was .first discovered ; in Norway at Kbraas ; in the Ural in large masses near Katherinenburg, and in the gold washings in grains ; in many parts of the United States, as the Barehills near Baltimore, Chester in Massachusetts, and Hoboken in New Jersey.. In Scotland it has been found in great abundance in Unst and Fetlar in the Zetlands, and also at Portsoy in Banff and other places. It is used in the preparation of various pigments, the chromate of potash being first produced, and then converted into chrome peroxide (chrome-green) or chromate of lead (chrome-yel- low). 337. FRANKLINITE, Berlhier, Phillips ; Dodecahedral Iron ore, Mohs. Tesseral ; and O . ooO being the most usual forms. The crys- tals, often rounded on the edges and angles, occur imbedded or united in druses ; it also forms granular masses. Cleavage, octahedral, but in general very imperfect. Fracture conchoidal or uneven ; brittle. Family.'] ELEMATJTE. 397 H. = 6 6'5 ; G. = 5*0 5*3. Opaque ; imperfect metallic lustre ; colour iron-black ; streak dark reddish-brown. B.B. infusible, but shines brightly and gives out sparks when strongly heated in the for- ceps. On charcoal, especially with soda in the reducing flame, forms a deposition of zinc ; with borax in the outer flame fuses to a red glass, which becomes brown when cold. Soluble in hydrochloric acid. Chem. com. probably (FC, zn, Mn) (re, ) Analyses. Iron JMang. perox. perox. Zinc oxide. Alu- mina. Silica. Water. Total. 1 2 8 4 66 66-10 68-88 41-93 16 14-96 18-17 7'60a 17 17-43 10-81 16-80 6*73 30-49 0*-20 0-40 2-97 0-56 0-40 99 99-25 98-99 100-19 Berthier. Thomson. Abich. Thomson. (a) Protoxide. Occurs with red oxide of zinc, calc-spar, and garnet at Franklin in New Jersey, and at Sterling in a vein with troostite ; and, according to Allan, also in the Altenberg mines near Aix-la-Chapelle. The Dysluite of Thomson, No. 4, also from Sterling, N, J., opaque, dark or yellowish-brown, with vitreous lustre, and G. = 4-5, seems this species with a large part of the peroxides of iron and manganese replaced by alumina. According to Rammelsberg, the iron is partly the protoxide = 12-55, partly the peroxide = 27*96. Breithaupt's Isophane, or isophane iron ore, crystallizing in octahedrons, iron- black, with brown streak, and G. = 5'01, seems also franklinite. 338. HAEMATITE, Hausmann ; Specular iron, Phillips ; Blutstein, Eisenglanz, Rotheisenstein, Werner ; Fer oligiste, Hauy ; Oligiste, Beudant; Rhombohedral iron ore, Mohs. Rhombohedral ; R 86, usual forms, R, OR, |R 143 , R, 2R, *P2 and ccP2, the general aspect of the crystals being rhombo- hedric when R, prismatic when |P2, or tabular when OR predomi- nates. The more common combinations are R . OR, OR . R (fig. 218), R . R . ooP2, R . |P2 . OR, P2 . R . R, (or w, P, s) (fig. 219). Fig. 218. Fig. 219. 398 HAEMATITE. [Oxidized Iron Ore The crystals are imbedded, or oftener attached and united in groups and druses. Macles occur with parallel axes, and mostly intersecting. It also appears in granular, foliated, and scaly masses, or botryoidal, reniform, columnar, or fibrous. Cleavage, rhombohedral along R, and basal, but seldom distinct, sometimes scarcely perceptible, and the basal often rather a foliated structure. Fracture conchoidal or uneven ; brittle, H. = 5*5 6'5 ; G. = 5*1 5-3. Opaque, or in very thin laminae translucent and deep blood-red. Lustre metallic ; colour iron-black to steel-grey, but often tarnished ; also various shades of red ; streak cherry-red or reddish-brown. Usually weak magnetic. B.B. in the reducing flame it becomes black and magnetic, and acts like iron peroxide. Slowly soluble in acids. Chem. com. p4, with 70-03 iron and 29'97 oxygen, but sometimes contains oxide of titanium, chrome, or silica, which then affect its action B.B. In a variety from St Gotthardt, v. Kobell found 85'33 iron peroxide, 5-01 iron protoxide, and 9*66 titanic acid; and in another from Swit- zerland, 94*82 iron peroxide, 3'57 titanic acid, and 1-61 manganese peroxide. According to H. Eose, the titanium in this mineral occurs as the acid. Some authors divide this species into two, the proper specular iron ore, with crystalline structure and high metallic lustre ; and the red haematite or more compact varieties. There is a gradual transition from the one to the other, and the difference is chiefly in the size of the individual parts. Some varieties have received particular names, as the micaceous specular iron (Eisenglimmer), with thin lamellar structure, which, when still finer or scaly, passes into the red iron froth (Eisenrahm). The red haematite or red iron, generally with inferior lustre, lower specific gravity (= 4'5 4'9) and hardness (= 3 5), and deeper blood-red or brownish-red colours, comprises the Fibrous red iron, (Rother Glaskopf, Werner ; Fer oligiste concretion^ Hauy), reniform, botryoidal, and stalactitic masses, often with an irregular concentric structure ; the compact and ochrey iron ores, similar masses with a more earthy or minute texture ; the reddle or red chalk, still more earthy, and used as a drawing material; and thejaspery, columnar, and lenticular clay iron, mere impure varieties with no essential dis- tinction. The magnetic property does not arise, as is often asserted, from a mixture of the protoxide of iron, for the pure peroxide can acquire magnetism and polarity often in a high degree. The experiments of Hausmann, Henrici, H. Rose, and others, show that it depends chiefly on the state of aggregation, the more crystalline and compact varie- ties being also the more highly magnetic, and more easily receiving Family.'} IRITE. 399 magnetism by contact. Von Kobell has named these Eisenrose, or Basanomelan, but they are not distinct. Haematite is one of the most abundant ores of iron. The specular variety occurs chiefly in the" older crystalline rocks, in large beds or veins. The mines of Elba, celebrated from antiquity, still furnish the finest crystals, which occur in druses of the massive variety along with pyrites and quartz. St Gotthardt, Framont in the Vosges mountains, Arendal, Langbanshytta in Sweden, Tilkerode in the Harz, Altenberg in Saxony, Capas in Brazil, Katherinenburg and Mschne-Tagilsk in the Ural, also produce fine crystals. Beautiful specimens of the micaceous variety occur at Zorge and other parts of the Harz, at Tincroft in Cornwall, Tavistock in Devonshire, in Wales, Cumberland, and Perthshire. At St Just in Cornwall, and various localities in Germany, it forms a constituent of granite ; and the Ita- birite of Brazil is a schistote or granular mixture of this mineral with quartz. It also occurs in volcanic rocks, as in Auvergne, on Vesu- vius, j33tna, and the Lipari islands, especially Stromboli, where some fine crystals, three inches broad and four long, have been procured. The red haematite is very common in the Harz and other places in Germany, and in fine reniform masses near Ulverstone in Lancashire, and in many other parts of Britain. The haematite is not very liable to decomposition, and the beauti- ful tarnish colours, like those on polished steel, arise less from a change of the surface than from a thin covering of some foreign mat- ter, such as the hydrated peroxide of iron. The haematite is occa- sionally produced from a gradual change of pyrites or of siderite, and sometimes appears in pseudomorphs, with the form of these mine- rals. At Lostwithiel in Cornwall, fine red crystals of pure iron per- oxide, with the exact dimensions of the gotheite, occur, which Hai- dinger considers pseudomorphs of the latter. The octahedral crystals from Brazil, named Martite by Breithaupt, are a similar formation after the magnetite. The ignition of coal mines has also produced it from the siderite ; and that found in volcanos, as Vesuvius and Stromboli, according to Covelli, is a result of the action of aqueous va- pours on chloride of iron. Mitscherlich has seen crystals of haematite formed in a similar manner in a potter's oven at Oranienburg. 339. IRITE, Hermann. Occurs in fine iron black scales with strong metallic lustre, which mark paper, either filling cavities in the larger pieces of native platina, or in more abundance mixed with the ferruginous platina sand of the Ural. G. = 6*506. Strongly magnetic. B.B. fused with nitre gives out the odour of osmium. Insoluble in acids. Chem. com. perhaps (ir, 6s, FC) ('ii, os? Or): or, by an analysis of Hermann, 62 '86 per- 400 LIMONITE. [Oxidized Iron Ore oxide of iridium, 10'30 osmium protoxide, 12-50 iron protoxide, 13'7 chrome oxide with traces of manganese (= 99 '36). It has recently been stated to contain also the new metal ruthenium. 340. LIMONITE, Beudant ; Brown Hematite, Phillips; Brown Iron ore, Allan ,- Brauneisenstein, Werner ; Fer oxide, Hauy, in part ; Prismatic Habroneme ore, Mohs. Crystallization unknown (but perhaps rhombic). It has only been found fine fibrous, in spherical, reniform, and stalactitic masses, often with a radiating texture, and dividing into curved concentric laminae with smooth or rough surfaces. Compact and earthy varieties also occur in various states of aggregation. Fracture fine fibrous, com- pact, or earthy. H. = 5 5'5 ; G. = 3'4 3 '95. Opaque ; lustre weak silky, glimmering, or dull ; colour brown, especially yellowish, clove, hair, and blackish-brown, also yellow and green ; streak yel- lowish-brown. In the closed tube yields water, and the powder be- comes red. B.B. in the outer flame also becomes red on ignition ; in the inner flame thin splinters fuse to a black magnetic glass ; with fluxes acts like iron peroxide. Chcm. com. essentially 2 pe + 3 H with 85'6 peroxide of iron (= 60 iron), and 14-4 water. Analyses. Iron perox. Watr. Mang. perox. Silica. Alu- mina. Phos. acid. Total. 1 82-0 2 62-93 3 80-76 4 83-38 5 82-24 82-87 7 8677 8 81-41 14-0 10-41 12-71 15-01 13-26 13-46 13-23 17-96 2-0 trace traced 1-0 22-20 4-58 1-61 4-50 0-67 6 : \7 1*84 2-63 1-33 ...a s'-oo ...c 99-0 98-71 101-60 100 100 100 100 KIO D'Aubuisson, Vicdessos. Kersten, Willsdruff. Rammelsberg, Carlshutte, Brunswick, v. Kobell, Kamensk, Perm. Do. Minden, Prussia. Do. Siegen. Amelung, Riibeland, Harz. Murray, Hiittenrode. (a) + 0'92 lime ; (6) with copper and lime ; (c) + 0-46 carbon. Three varieties, ihQjftbrous (brauner Glaskopf}. the compact, and the ochrey, are distinguished, but they are usually found together, and differ only in their state of aggregation. An uncertainty in regard to the composition of limonite arises from its mixture with other hydrated oxides of iron. In many cases it has been produced from the decom- position of other iron ores ; and is often formed by water, containing carbonic acid, extracting from rocks the carbonate of the protoxide of iron, which, on exposure to the atmosphere, loses the carbonic acid, and is deposited as a hydrated peroxide of iron. A similar change often takes place on the carbonate of iron contained in some rocks, which then assume a brown hue ; and the hydrated peroxide of man- ganese, often mixed with the limonite, has had a similar origin, but has a great tendency to separate in dendritic forms. Iron rust is a similar product, the hydrated peroxide being frequently united with Family.'] LIMONITE. 401 the carbonate of the protoxide. Iron rust absorbs ammonia from the atmosphere, and this alkali has been observed in many limonites. Like other ores of iron, it also contains a small proportion of arsenic, in general too minute for ordinary methods of detection. Limonite occurs in beds, veins, and nests, in rocks of all ages and formations, often forming the upper portion, whilst the lower consists of unchanged siderite. It is frequently associated with heavy spar, or with calc spar, fluor spar, and quartz, the last often forming sta- lactitic masses of bluish calcedouy. It is a valuable ore of iron, and is wrought as such in many parts of the Harz, near Schmalkald and Camsdorf in Thuringia, at Siegen near Bonn, in Naussau, Styria, and Carinthia. The Pyrenees and Basque Provinces possess it in great abundance, and also Siberia, Brazil, and the United States. In Bri- tain it is found in Cornwall, at Clifton near Bristol, Sandlodge in Zet- land, and in many other places. The metal it yields varies much in quality, according to the substances mixed with the ore, but is usually good, uniting hardness with tenacity. Limonite frequently occurs mixed with other mineral substances, and has then received distinct names, especially from the German miners. Their Braunerz or Mine douce is limonite with carbonates of lime or magnesia, amounting, in a variety from Styria analyzed by Karsten, to about 5 per cent. each. Some are similar mixtures with clay. The Kupferbraun or Ferruginous red oxide of Copper of Phillips, sometimes with 22 per cent, suboxide of copper, is reddish or yellowish-brown, with a yellowish-brown streak, and generally occurs near copper mines. The Kupferpecherz or Pechkupfer of Hausmann is a similar combination of peroxide of iron with copper protoxide (12 per cent.), silica (18), and water, from Siberia. The Umber ( Umbra, Hausmann, Terre d 'ombre, Hauy) from Cyprus, analyzed by Klaproth, contained 48 per cent, peroxide of iron, 20 peroxide of manganese, 13 silica, 5 alumina, and 14 water ; but other umbers vary much in composition, and that from Cologne is merely brown coal finely pulverized. The Stilpnosiderite and Lepidokrokite of Ull- mann seem partly limonite, partly gotheite. Hausmann considers the Yellow ochre (Gelbeisenstein) as a distinct species, with chem. com. 4 + 2 H , or 81*6 peroxide of iron and 18'4 water. In a specimen from Artana in Valencia, Proust found 78'57 peroxide of iron and 21-53 water ; and many varieties contain sulphate of iron and other substances, proving it to be a mere product of decomposition. Some varieties are used as a yellow, or when burnt as a reddish-brown pigment. Bunsen has shown that the pure sub- stance is a valuable antidote to the poison of arsenic. Bog iron ore (Raseneisenstein, Morasterz, Wiesenerz) is also an Ll 402 GOTHEITE. Oxidized Iron Ore hydrated oxide of iron with no definite composition, and often con- taining thirty to fifty per cent, of impurities. Phosphoric acid is a very frequent constituent, sometimes to 11 per cent. ; and also organic acids from plants ; Wiegmann in one case finding as much as 14 per cent, of humic acid (?). Bog iron ore occurs chiefly in bogs, meadows, and lakes, especially in the level districts of northern Germany and Sweden. The peroxide is derived from the decomposition of the iron ores, which either form beds or are mixed with the rocks. That found in great abundance in the Smoland lakes has probably been produced from the iron pyrites of the greenstone in the vicinity, as Svanberg observed that it usually contains sulphuric acid, whilst the other elements are such as the decomposed hornblende could furnish. In Britain it is most abundant in the northern and western islands of Scotland. It is easily fused, and serves well for castings, but, from the mixture of phosphoric acid, is unfit for sheet or plate iron, being what is technically termed cold short. 341. GOTHEITE, Beudant; Brown iron ore, Hydrous oxide of Iron, Phillips ; Pyrrhosiderit, Hausmann ; Nadeleisenerz, Naumann ; Prismatoidal Habroneme Ore, Mohs. Rhombic; P with polar edges 121 5' and 126 18', ooP 94 53', ooP2 130 40', Poo 117 30'. The usual combination is Pao . ooP . OP . 2P~oo . ooPoo ; and the crystals are generally thick tabular, or broad prismatic (fig. 227), from predominance Fig. 227 f t ^ ie bra-chypinakoid, which is strongly marked with vertical striae. The macles are united by 2Poo , and the chief axes are inclined at 59 20' to each other. It also occurs massive and foliated or granular. Cleavage, bra- chydiagonal very distinct, macrodiagonal less so, and basal imperfect. H. = 6 ; G. = 5'4 6-4 (G. = 5'469 M m 410 COLUMBITE. [Tin- Ore 5-708 in American varieties ; 5*976 6'390 in Bavarian). Opaque ; lustre metallic adamantine ; colour brownish or iron-black ; streak reddish-brown or black. B.B. infusible alone ; with borax forms a dark blackish- green glass. Not affected by acids until after fusion with potash, or better with the bisulphate of potash. Chem. com. protoxide of iron and protoxide of manganese (re, in) with a metallic acid, partly niobic, partly tantalic or some similar acid in indefinite proportions. Analyses. Niob. acid. Iron prot. Mang. prot. Tin ICopr. oxide.! prot. Lime. Total. 1 73-90 15-65 8-00 ... i .. ...a 97-90 Thomson, Middletown, (G.4'8038.) 2 78-83 16-66 471 0-29 0-07 0-456 101-23 Schlieper, Do. (G. 5-469 5-495). 3| 79-62 1637 4-44 0-47 0-06 trace 100-96 H. Rose, N. America (G. 5'708 in pow- 4 77-30 13-00 9-50 0-50 M ...c 100-30 Marignac, Do. [derK 3 79 65 14-00 j 7-55 0-50 ... ...d ldl'75 Thomson, Bodenmais (G. 6-038). 6 81-07 14-30 1 3-85 0-45 0-13 trace 99-80 H. Rose, Do. (G. 6-39). 71 81-34 13-89 3-77 0-19 o-io trace 99-29 Do. Do. 81 79-68 15'JO 4-65 0-12 0-12 trace 99-67 Do. Do. (G. 5-7.) 9 80-64 15-33 4-65 0-lOc 0-21 100-93 Awdejew, Do. (G. 6 -021). o 79-73 14-77 4-77 0-10 1-51 ... 100-88 Jacobson, Do. (G. 5-976)- 111 80-47 8-50 6-09 100 Hermann, I Imen, M. G. 5-43 573). 12 7860 12-76 4-48g 0-004 075 100-17 Bromeis, Do. (G. 5-461). ia) + 0-35 water ; (&) + 0-22 nickel oxide; (c) + trace of yttria; (d) + 0-05 water; (e) with copper ; (/) + 2-44 magnesia, 2-00 yttria, and 0-50 uranium protoxide; (g) with yttria, + 3-01 magnesia and 0-56 uranium peroxide. The streak in Nos. 1, 2, 3, 8, 10 was dark reddish-brown -, in No. 9 rather darker ; and in Nos. 5, 6, 7 black. The specific gravity of No. 9 was 6-078 in powder. Hatchett first recognised the peculiar nature of the metallic acid in this mineral in a specimen said to come from Neatneague in North America, but probably from one of the localities mentioned below. This acid was considered identical with that in tantalite till the la- borious researches of H. Rose showed its diversity, and that it con- sisted of two acids resembling the tantalic, but distinct. One is the oxide of a new metal Niobium, but the true character of these substances is still uncertain. The specific gravity of the acid varies with that of the mineral from which it is extracted, being 6 -542 from No. 6, 6-13 from No. 9, 5'452 from No. 3, and 4/37 from No. 7, in which H. Rose says it is almost pure niobic acid with traces of pe- lopic and tungstic acids. This mineral was first described as monoclinohedric, a view still .maintained by Haidinger ; but Dana, from whom the above angles are taken, makes it rhombic. The finest crystals occur in a felspar quarry at Middletown in Connecticut, where one was found weighing fourteen pounds. Haddam in Connecticut, and Chesterfield in Massa- chusets, are other American localities. In Bavaria, it occurs in the granite of the Rabenstein at Zwiesel, near Bodenmais. Thomson distinguished No. 1 under the name of Torrelite. Family.'] TANTALITE. 411 347. TANTALITE, Ekeberg, Phillips; Ferro-tantalite, Thomson, Dana; Kimito-tantalite, Prismatic Tantalium ore, Mohs. Rhombic ; primitive form, according to Nordenskib'ld, a rhombic pyramid of 126, 112 307 and 91 42'. The crystals prismatic, and lengthened along the chief axis. It also occurs massive in imbedded grains. Cleavage, macrodiagonal, brachydiagonal, and basal, but veiy indistinct. Fracture conchoidal or uneven. H. = 6 6'5 ; G- = 7'1 8. Opaque; lustre semimetallic, inclining to adaman- tine or resinous. Colour iron-black ; streak cinnamon or coffee- brown. B.B. infusible alone, but with borax forms a transparent glass, becoming opaque by flaming. Scarcely affected by acids. Chem. com. protoxides of iron and manganese with tantalic acid. Analyses. Tan- talic acid. Iron prot. Mang. prot. Tin oxide. Copper protox. impure. Lime. Total. 1 83-2 7-2 7-4 0-6 98.4 Berzelius, Kimito, G.7'30. 2 85-85 12-97 1-61 0-80 ... 0-s'o'a 102-51 Do. Do. 3 83-44 1375 1-12 trace 9831 Nordenskiold, Tammela. 4 84-15 14-68 0-90 0-32 1*81 0-07 101-93 .Jacobson, Do. G. 7'197. 5 8470 14-29 1-78 0-50 0-04 101-81 Brooks, Do. 6 82 98 14-62 trace 1-00 ... .'.'.'& 99-23 iDamour, Limoges, G. 7'64 765. 7 77-83 8-47 4-88 6-81 0-24 0-50 98-73 Wornum. Tammela, G. 7'187. 8 6699 6-89 7-16 1675 2-40 100-19 (Berzelius, Finbo. 9 66-34 10-50 5-90 8-40 l-50c 98-76 Do. Broddbo. 10 68-22 8-60 1 6-43 8-26 l-19d 98-89 Do. Do. (a) + 0-72 silica ; (b) + 0-42 silica ; (c) + 6-12 tungstic acid ; (d) 6-19 do. In No. 1, the streak was coffee-brown ; in No. 2, cinnamon-brown. ; and, according to Berzelius, it contained tantalium oxide, not the acid. Nos. 4, 5 were massive, with dark reddish-brown streak. No. 7 was crystallized, with G. = 7'112 7'155 in powder. Ano- ther specimen, also from Tammela, had G. = 7'476, and in powder, 7'51, whilst Ekeberg raises it to 7'936. This mineral has been found in seven localities inFinnland, usually in a granite containing oligoclase or albite, and generally with eme- rald 'or turmaline. The finest crystals are procured at Harkasaari, in the parish of Tammela, where it is associated with gigantolite. A massive bluish black variety, with greyish-black streak (No. 6), is found in the pegmatite near Chanteloube in France. The Cassiterotantalite of Hausmann includes the varieties containing tin oxide in considerable amount. They have a lower specific gra- vity, = 6'2 6'5. B.B. with borax easily fusible to a transparent yellow glass, and with soda in the reducing flame yield tin. They are found at Finbo and Broddbo, near Fahlun, with cassiterite, and seem often a mere mixture .of this mineral with tantalite. 412 YTTROTANTALITE EUXENITE. [Tin Ore 348. YTTROTANTALITE, Ekeberg, Phillips, Dufrenoy ; Yttro- columbite, Dana. Crystallization unknown, but appears in indistinct rectangular, or oblique four-sided, or irregular six-sided prisms ; also in imbedded grains, lamellae, and minute crystalline portions. Cleavage in one direction. Fracture conchoidal or uneven. H. = 5 5'5 ; G. = 5*39 5'88. Opaque, or in thin splinters translucent. Berzelius distinguishes (a) Black Yttrotantalite, iron-black, with semimetallic lustre, and greenish-grey streak, G. = 5*395 ; (b) Dark or Brown Yttrotantalite, brownish-black, with bright brown streak, and vi- treous or resinous lustre ; (c) Yellow Yttrotantalite, colour yellowish- grey or brown, often stripped or spotted, streak white, lustre resinous or vitreous, G. = 5'88. B.B. infusible alone, but become brown or yellow ; and with borax form a transparent yellow glass. Not affected by acids. Chem. com. according to Berzelius, tantalic acid and yttria, but the former partly replaced by tungstic acid, the latter by lime. Analyses. Tantalic acid. Tungstic aad. Yttria. Lime. Uranium peroxide. Iron perox. Total. 1 2 57-00 51-82 8-25 2-59 20-25 38-52 6-25 3-26 0-50 1-11 3-50 0-55 95-75 97-85 Berzelius (black), Ytterby. Do. (brownish), Do. 3 4 60-12 59-50 1-04 1-25 2978 29-90 0-50 3-29 6-62 3-23 1-16 2-72 99-22 .99-89 Do. (yellow), Do. Do. (do.) Do. In Nbs. 2, 3, the tungstic acid contained tin ; by ignition the black variety lost 5-74 per cent, water ; the yellow 4"85 per cent., and of the brown some that retained then* colour 2-72, others which became yellow 6-06 per cent. It was first found near Ytterby in Sweden, in flesh-red felspar with gadolinite ; and since in the granite veins at Finbo and Kararfvet near Fahlun. Hermann's yttrotantalite (yttro- ilmenite) from the Ural is the samarskite, see p. 286. 349. EUXENITE, Scheerer. Rhombic probably, the crystals formed by the macropinakoid, two prisms, and two brachydomes. Also occurs compact, with no trace of cleavage. Fracture imperfect conchoidal. H. = 6-5 ; G. = 4*6. Opaque, or iji thin splinters translucent and reddish-brown ; lustre metallic vitreous ; colour brownish-black ; streak reddish-brown. B.B. infusible alone ; with borax in the outer flame forms a yellow glass, inclining to brown, and retaining its colour when cold. Not affected by acids. Chem. com. uncertain. Scheerer found 49-66 tantalic (with some titanic) acid, 7 '94 titanic acid, 25'09 yttria, 6'34 protoxide of uranium, 2-18 protoxide of ce- rium, 0-96 lanthamum oxide, 2*47 lime, 0-29 magnesia, and 3-97 wa- Family.'] FERGUSOKITE SPHENE. 413 ter = 98.90 ; but from the small amount of the fossil, and imperfect means of separating the various constituents, these numbers are mere approximations. The specimen was from Jb'lster in Northern Ber- genhuus in Norway ; but it has since been found at Arendal, in rough crystals with lenticular faces. Scheerer now says that it contains no tantalic but niobic acid, and hence is nearer the columbite than the yttrotantalite. 350. FERGUSONITE, Haidinger, Phillips, Dufrenoy; Pyramidal Melan ore, Mohs. Tetragonal^ and pyramidal-hemihedric ; P = 128 27'. The usual combination is P . o>P3 OP, sometimes also with the half ditetra- gonal pyramid 3P3 predominating very distinctly (fig. 228). Fig. 228. Cleavage, in indistinct traces along P ; fracture imper- fect conchoidal ; brittle. H. = 5'5 6 ; G. = 5*8 5'9. Translucent in thin splinters ; lustre semimetallic ; colour brownish-black ; streak pale-brown. B.B. infu- sible ; with borax forms a glass yellow when hot. Chem. com. R S ia , where R is chiefly yttria with a little protoxide of cerium and zirconia ; or, by HartwalPs analysis, 47'75 tantalic acid, 41*91 yttria, 4'68 cerium protoxide, S'02 zirconia, TOO tin oxide, 0'95 uranium peroxide, and 0'34 iron peroxide (= 99 -65). It was found by Giesecke imbedded in quartz near Cape Farewell in Greenland, and named after the late K. Ferguson of Raith. 351. SPHENE, Hauy, Phillips, Hausmcmn ; Titanite, Klaproth ; Menak- Erz, Werner; Prismatic Titanium ore, Mohs. Monoclinohedric ; C = 85 6' ; ooP (/) 133 54', |Poo (x) 52 21', Poo (y) 34 27', OP (P), ( ooPoo ) (?), ( oo P3) (M) ; and the hemi- pyramids (P2) (n) 136 6', are in general the predominant forms. The combinations vary extremely, and their apparent diversity is in- creased by various abnormal formations. The usual aspect of the crystals is either horizontal prismatic when the above or other hemi- domes predominate along with OP; or tabular when Poo or OP predominate ; very often oblique prismatic, from the prevalence of (f P2) ; rarely vertical prismatic from ooP and ooPoo (figs. 229, 230). Twin crystals are frequent, united by the basis (P), and either in contact or intersecting. It also occurs imbedded, in granu- lar or foliated masses. Cleavage, in many varieties prismatic along ooP; in others, clinodomatic along (Poo) (r) 113 30', imperfect. H. = 5 5'5 ; G. = 3'4 3'6. Semitransparent or opaque ; lustre adamantine, or often resinous ; colour brown, yellow, or green, and 414 SPHENE. [Tin Ore sometimes varying on the same crystal. B.B. slightly intumesces, Fig. 229. Fig. 230. M and fuses on the edges to a dark glass. With borax forms a trans- parent yellow glass ; with salt of phosphorus in the reducing flame, especially with tin, shows the reaction for titanic acid. Imperfectly soluble in hydrochloric, wholly in sulphuric acid, which dissolves the titanic acid, and forms sulphate of lime. Chem. com., according to H. Rose, ca 2 si + fi 2 si, with 31-8 silica, 40'4 titanic acid, and 28'3 lime, part of the last being replaced by iron protoxide in the brown varieties. Berzelius, on the other hand, considers that the whole silica will combine with lime as the far stronger base, and hence gives the formula 2 da 'si + ca Ti 3 . Analyses. 2 3 4 5 6 7 Silica. Titan, acid. Lime. Iron prot. Mang. prot. Total. 32-52 32-29 30-63 31-20 29-8 30-4 32-26 43-21 41-58 42-56 40-92 43-0 42-0 38-57 24-18 26-61 25-00 22-25 S3-6 24-3 27-65 0-96 3-93 5-06 trace trace 0-76a 2 : 9 3-6 076a 99-91 101 '44 102-12 9943 99-3 1003 100 Fuchs, Schwarzenstein, G. 3'44, yellow H. Rose, Zillerthal, G. 3'535, greenish Brooks, Passau. brown. Rosales, Arendal, Do. Delesse, St Marcel, greenovite. Do. Do. Do. Marignac, Do. Do. (a) Peroxide. Sphene occurs chiefly disseminated in the crystalline strata, and in igneous rocks of all ages, but especially in some sj^enites. It is also found in beds with magnetite, copper pyrites, and other ores ; and in veins with rock crystal, adularia, albite, asbestus, talc, and chlorite, the last often covering or penetrating the crystals. Fine specimens of sphene are found in many parts of the Alps, as in Dau- phine near Mont Blanc, on St Gotthardt, at Dissentis in Graubtindten, at Schwarzenstein, and other parts of Tyrol. In the Ural it occurs near Slatoust. Common sphene is found in granitic or hornblendic rocks in the iron mines at Arendal, where one yellow tabular crystal was 6 inches long and 5 broad ; also in various parts of Sweden, in Saxony near Dresden, in Moravia and Thuringia, all in syenite. Small crys- Family.] BROOKITE RUTILE. 415 tals are occasionally met with in syenite at Criffel and near Strontian in Scotland. It occurs in clinkstone at Aussig and Teplitz ; in basalt near Wessel in Bohemia ; and at Lake Laach in ejected blocks with glassy felspar. It is also common on Vesuvius, and in France, Greece, Brazil, the United States, and Greenland. The Greenovite from St Marcel in Piedmont is merely sphene with part of the lime replaced by protoxide of manganese, giving it a flesh- red colour, and reddish streak. Dufre'noy makes it a distinct species, and says that it differs in crystallization, but the variation is very small, and scarcely essential. 352. BROOKITE, Levy. Rhombic ; P with polar edges 135 46' and 101 37', ooP 100*. The usual combination is ooPoo . ooP . P (fig. 231). More complex Fig. 231. crystals occur, but the brachypinakoid always greatly predominates, giving them a tabular aspect. Cleavage, macrodiagonal. H. = 5'5 6 ; G. = 4-128 4-167. Opaque or translucent ; lustre metallic adamantine ; co- lour yellowish, reddish, or hair-brown ; streak yellowish- white. B.B. infusible ; with salt of phosphorus forms a brownish-yellow glass. Chem. com., according to H. Rose, xi or titanic acid, with, at most, 1*4 per cent, peroxide of iron. Brookite was long considered a variety of rutile, with which, and anatase, it agrees in chemical composition, but differs from it in its lower specific gravity, and also in crystallization. The gravity, how- ever, increases on ignition, having risen to 4-197 in some crystals heated for 45 minutes over a spirit lamp. It was first found with anatase at Bourg d'Oisans in Dauphine', and since at T6te-Noire near Chamouni, and in the Steinthal nearAmstag in the Canton Uri. The finest crystals, sometimes half an inch in diameter, occur with albite and quartz on Snowdon and near Tremaddoc in North Wales. 353. RUTILE ; Rutil, Nigrine, Werner; Peritomous Titanium ore, Mohs. Tetragonal ; P 84 40', Poo 65 34' ; the usual combinations are Fig. 232. P osP 00 - P) and ooP3 . P. The crystals (fig. 232) always prismatic, often acicular or capillary, occur at- tached or imbedded. Macles are very common (like fig. 225, p. 407 above), united by a face of Poo , and hence with their chief axes inclined at 114 26'. These are often repeat- ed, forming a reticulated mass of acicular and capillary crystals (Sagentte). It is also found massive and im- bedded in crystalline or granular aggregates. Cleavage, 416 ANATASE. [Tin Ore prismatic along ooP, and ocPoo perfect ; fracture conchoidal or un- even ; II. = 6 6'5 ; G. = 4-2 4'3 Translucent or opaque ; lustre metallic adamantine ; colour reddish-brown to dark blood-red and cochineal-red, also yellowish-brown to ochre-yellow and black (Nigrine) ; streak yellowish-brown. Acquires negative electricity by friction. B.B. unchanged alone ; with borax in the oxidating flame forms a greenish, in the reducing flame a dirty violet- coloured glass. Not affected by acids. Chem. com. titanic acid, xi , with 60'3 titanium and 39'7 oxygen, sometimes with 1'5 per cent, peroxide of iron (H. Hose and Damour). In a black variety from Freiberg, be- coming blood-red by ignition, Kersten found 2-4 per cent, of peroxide of iron and magnetic iron, the latter separable from the pulverized mineral by a magnet. Kersten conjectures that the black colour may be caused by peroxide of titanium. In rutile from Karing-Bricka in Westmanland, Ekeberg and Vauquelin found chrome. Eutile occurs chiefly in mica and chlorite slates, in gneiss and granite. It shows a strong tendency to associate with silica ; its long acicular prisms often investing the surface of rock crystal, or penetrating it in every direction. Fine crystals occur in many parts of the Alps ; at Buitrago in Spain, St Yrieux near Limoges, Rosenau in Hungary ; also in the Ural, Brazil, and North America. It occurs in gneiss near Brevig, and it has been said in the magnetic iron ore at Arendal, but probably erroneously. It is common in many parts of the Scottish Highlands, and fine large prisms are found on Crian- larich in Perthshire. It is used in painting porcelain to produce a yellow colour. Nigrine is merely the black variety, sometimes mixed with per- oxide of iron or manganese. It occurs in many igneous rocks, or in the sands derived from them, as in the gold washings of Ohlapian in Siebenburg. Warwickite of Shepard, dark hair-brown or iron-grey, G. = 3 3 '29, and said to crystallize in oblique rhombic prisms, contains 64'71 titanium, 7'14 iron, O80 yttrium, 27 '33 fluorine with .race of aluminium ( 99'98), Shepard. Berzelius considered it an impure rutile mixed with titanite, and Mr Hunt finds that it contains no fluorine, but is a silicate and titanate of iron, magnesia and alu- mina, with 7 per cent, water. It is found near Edenville in New York. 354. ANATASE, Hauy ; Octaedrite, Saussure, Werner ; Pyramidal Titanium ore, Mohs. Tetragonal ; P 136 47' (Phillips). The crystals usually formed of P, P . OP (fig. 233), or P . fP, are attached singly, or loose. Cleavage, basal and pyramidal along P, both perfect. Brittle ; H. = 5*5 6 ; Family.'} PECHURANE. 417 G- = 3-83 3'93. Semitransparent or opaque ; lustre metallic-ada- Fig. 233. mantine ; colour indigo-blue, sometimes almost black, hyacinth-red, honey-yellow or brown, rarely colourless ; streak white. *" Becomes negative electric by friction. B.B, infusible, but when heated shows a sudden gleam of reddish-yellow light (Brewster) ; with borax it forms a glass which in the reducing flame is yellow, but at length becomes violet-blue ; only soluble in warm con- centrated sulphuric acid. Chem. com. titanic acid with a little per- oxide of iron, or rarely tin oxide (Vauquelin and H. Rose). In a spe- cimen from Brazil Damour found 98*36 titanic acid, I'll peroxide of iron, and 0-20 tin oxide (= 99'67). Crystals from Brazil, with a specific gravity of 3 -927 and 3-917, after 45 minutes' exposure to a red heat, had G. = 4'117 and 4-125 ; and after three hours in a strong red heat, G. = 4-166 and 4-161, or when thoroughly freed from extraneous matter, 4-233 and 4-251. Thus anatase first attains the gravity of brookite, and then both that of rutile, so that these three minerals are only distinguished per- manently by their very distinct crystallization. Anatase is also remarkable for its electric properties, which first led Hauy to suspect its metallic nature. Hausmann and Henrici, in a blue crystal with yellow middle from Dauphine", observed a com- plete and immediate discharge of the electricity with sparks on con- tact with the conducting wire \ in a yellow transparent crystal from Brazil there was almost no discharge, even after a considerable in- terval, and no sparks. In two other crystals, partly of a blue colour, the discharge was immediate, with a strong spark. In rutile the dis- charge was very imperfect. Anatase occurs in granite, diorite, chlorite slate, mica slate, and transition strata, in druses or small irregular veins, often with quartz, felspar, albite, axinite, garnet, and chlorite. The finest crystals are from the Alps, as near St Cristophe in Dauphine, the Maggia valley in the canton Tessin, in the Valois and Salzburg. It is found in the Fichtelgebirge, in Spain, at Slidre in Norway (not at Arendal), and in the Ural. Fine crystals occur in Brazil in Minas Geraes in the sand of a brook near Itabiro de Matto Dentro, with diamonds, for which they have sometimes been mistaken. It also occurs in Corn- wall in granite. 354. PECHURANE, Hausmann; Uranpecherz, Werner; Pitch- Blende, Phillips ; Uranium ore, Allan ; Uncleavable Uranium ore, Mohs. Amorphous. Generally massive and disseminated, also reniform 418 PLATTNERITE. [Tin Ore with a columnar or curved lamellar structure. Fracture conchoidal or uneven and polished. H. = 5-5 ; G. = 6'468 or sometimes 7*9 8. Opaque ; lustre imperfect metallic or resinous ; colour greyish, green- ish, or brownish-black ; streak greenish-black. B.B. infusible alone ; with borax and salt of phosphorus it forms in the oxidating flame a yellow, in the reducing flame a green glass. Not affected by hydro- chloric acid, but is easily soluble in warm nitric or nitro-chloric acid. Chem. com. proto -peroxide of uranium, oru \j"i with 84 -78 uranium and 15'22 oxygen, but with many impurities. Analyses. InSE.!^ Iron. Man- ganese Lime. Mag- nesia. Silica. Watr. Arse- nic. Total. 1 72-OOai ... 2 79'lScj 6-20 3 \75-94g \ 4-22 3-03 3-106 0'05a V 826 6-00 2-81 5-24 0-46 2'07 4-26 5-3(1 3-48 1475 0-36 1-85 traced M3e 8-60/ 99-36 99-09 100-89 (a) Peroxide; (6) protoxide; (c) proto-peroxide ; (d) + 2-30 phosphoric acid, with trace of fluoric acid; (e) + 0-65 bismuth, with lead and copper; (/) + 0-60 sulphur, 0-25 soda, and 3-32 carbonic acid ; (, with 86*2 lead and 13'8 oxygen, but with a trace of sulphuric acid. Probably from the Leadhills in Scotland. Family.'] PYROLUSITE. 419 HI. FAMILT. MANGANESE ORES. 356. PYROLUSITE, Hai&nger, Allan; Grauer Braunstein, Werner, in part ; Manganese oxide, Hauy, in part ; Prismatic Man- ganese ore, Mohs. Rhombic ; ooP 93 40' (also 99 36', Breithaupt}. The crystals are usually short prismatic, and either bounded on the ends by flat domes, or divided into numerous points (fig. 234). Other crystals are thin tabular. Generally it occurs massive and disseminated, or in botry- Fig. 234. oidal, reniform masses, with a radiating columnar or fi- brous structure ; or in confused fibrous, earthy, or compact varieties. Cleavage, prismatic along ooP, and brachydia- gonal ; rather brittle or friable ; H. = 2 2*5 (lower when fibrous or earthy) ; G. = 4*7 5. Opaque ; lustre semimetallic, or silky when fibrous ; colour dark steel-grey, bluish, or iron-black ; streak black and soiling. B.B. infusible, but, strongly ignited on charcoal, it loses 12 per cent, oxygen, and is con- verted into the brown protoperoxide, With borax and salt of phos- phorus it shows reaction for manganese. Soluble in hydrochloric acid, with large evolution of chlorine. Chem. com. Mn, with 63 '6 manganese and 36-4 oxygen. Analyses. 1 2 3 4 Mang. proto- perox. Oxy- gen. Baryta. Watr. Silica, &c. Total. 8356 84-OG 85-62 87-0 14-58 1178 11-60 11-6 6-53 0-66 1-2 1-86 1-12 1-57 5-8 : 51 0-55 0-8a 100 100 100 108-3 Arfvedson, Undenaes. Turner, Elgersburg. Do. Ihlefeld ? Scheffler, Ilmenau. (a) + 1-3 iron peroxide, 0'3 lime, and 0-3 alumina. Pyrolusite was formerly confounded with manganite, but differs in crystallization, and in containing no water. It is best distinguished by the colour of the streak, and its softness, often so great as to soil the fingers. It occurs chiefly in beds in gneiss, clayslate, porphyry, and the older rocks, or in veins often with calc-spar, heavy spar, and ores of iron and manganese. It sometimes has been produced by the decomposition of the latter ; and crystals of manganite are found only partially converted into pyrolusite. It is also a common pseudomorph after calc-spar. This ore is extensively wrought in many places, as at Ilmenau and Elgersburg in Thuringia, at Vorderehrensdorf in Moravia, and in do- lomite near Giessen. Fine crystals are obtained at Ihlefeld, and near Goslar in the Harz, and at Johann-Georgestadt in Saxony. It also 420 POLIANITE. [Manganese Ore occurs in various parts of Westphalia, Bohemia, France, Hungary, and Siebenburg, and in Brazil near Villa Ricca. In Britain it Ls found in Cornwall and Devon. Pyrolusite gives off 10 or 11 per cent, oxygen at a red heat, and hence is employed to remove the brown and green tints in glass, arising from carbonaceous matter or protoxide of iron. This property has given occasion to its name, and the French, for the same reason, fancifully term it le savon des verriers. It is also used for producing oxygen, chlorine, and chloride of lime, in painting glass and enamel work, for glazing brown pottery, and colouring certain of the finer varieties, its softness and want of cohesion proving advantageous for many of these purposes. Like other ores of manganese, it is thought beneficial when mixed -with iron ores, both counteracting the bad effects of the heavy spar they 'may contain, and improving the quality of the iron and steel. Varvacite of R. Phillips, found in Warwickshire, seems a result of the tendency of mariganite to exchange the water for oxygen, and is intermediate between it and pyrolusite. Phillips found in it 63*3 manganese, 31 '7 oxygen, and 5 water. It chiefly occurs in pseudo- morphs after scalenohedrons, R 3 , of calc-spar ; but also in crystals with ooP = 99 36', according to Breithaupt, or in columnar and fibrous masses. H. = 2'5 3 ; G. s= 4'5 4-6. Colour iron-black to steel -grey, with black streak, and semimetallic lustre. Turner ana- lyzed a similar mineral from Ihlefeld in the Harz. 357. POLIANITE, Breithaupt. Rhombic ; ooP 92 52', Poo 1 1 8. The crystals of these forms with OP, ooP< , ooPoo , and two macroprisms, are generally short prismatic and vertically striated. It also forms granular masses. Cleavage, brachydiagonal perfect. H. = 6'5 7 ; G. = 4'84 4*88. Opaque ; lustre weak metallic ; colour light steel-grey. B.B. acts like pure hy- peroxide of manganese. Chem. com Mn, or identical with pyrolusite. In a specimen from Maria-Theresa Zeche near Platten in Bohemia, Plattner found 87'27 protoperoxide of manganese, 12-11 oxygen, 0'17 iron peroxide and alumina, - 13 quartz, and 0'32 water (= 100). This gives 99'38 per cent, hyperoxide of manganese, and Rammels- berg has confirmed its accuracy. Hence Breithaupt is probably cor- rect in considering this as the original hyperoxide of manganese, whilst pyrolusite is a mere product of the decomposition (oxidation^) of other ores mixed with water and various impurities. Other loca- lities of polianite are Schneeberg, Geyer, and Johann-Georgenstadt in Saxony, and the Eisernen Haardt in Siegen. Family.'] MANGANITE HAU8MANNITE . 421 358. MANGANITE, Haidinger ; Grauer Braunstein, Werner in part ; Grey Oxide of Manganese, Phillips; Grey Manganese, Allan ; Prismatoidal Manganese ore, Mohs. Rhombic, sometimes hemihedric ; cP (M) 99 40' ; ooP 2 (/) 118 42', OD | 103 23', Poo (d) 114 19'. The crystals always pris- matic, from the predominance of many prisms, are generally bounded at the ends by Poo, P3 (#), or OP (fig. 235), with ooP2 (r), 2P (m), Fig. 235. and 2P2 (n). They are marked by strong ver- tical stria3, and verj r often grouped in bundles (a kind of made), or united in druses. It also forms radiating, columnar, or fibrous, and more rarely granular aggregates. Cleavage, brachydiagonal veiy perfect, basal and prismatic along o>P less M i perfect. Rather brittle. H. =3 "5 4 ; G. = 4'3 4-4. Opaque ; lustre imperfect metallic ; colour dark steel-grey to iron-black, or often brownish-black and tarnished ; streak brown. B.B. acts like manganese peroxide, and is infu- sible ; with borax in small quantity forms a violet- blue glass. Soluble in warm concentrated hydrochloric acid, and slightly in concentrated sulphuric acid, which acquires a red tinge from the powder in a few days. Chem. com. Mn + H, with 89'9 manganese peroxide and 101 water, closely agreeing with the ana- lyses : Manganese. Oxygen. Water. 1. 89-92 10-08 = 100, Arfvedson, Undenaes. 2. 62-86 27-64 9'50 = 100, L. Gmelin, Ihlefeld. 3. 62-72 27-18 10-10 = 100, Turner, Do. (m. of 2). Manganite occurs abundantly in veins in porphyry with calcspar and barytes at Ihlefeld in the Harz ; also in several parts of Thu- ringia. In irregular veins in gneiss at Granan near Aberdeen, Chris- tiansand in Norway, Undenaes in Sweden ; in France, Nova Scotia, and other places. It is used for the same purposes as the pyrolusite, but is less valuable from giving off less oxygen. When changing to pyrolusite, the sp. gr. of manganite rises to 4'5 4'8 ; and the streak becomes black. 359. HAUSMANNITE, Haidinger; Glanzbraunstein, Hausmann; Pyramidal Manganese ore, Mohs. Tetragonal : P 117 54', Poo 99 11'. The usual forms are P and P . P, and the crystals, always pyramidal, are grouped in druses. 422 BRAUNITE. [Manganese Ores Macles are common, united by a face of P (fig. 81, p. 41 above), and often symmetrically repeated on all the four polar edges of a central crystal. It also forms granular aggregates. Cleavage, basal rather perfect ; less distinct along P and Poo . Fracture uneven. H. = 5'5 ; G. = 4*7 4 '8. Opaque ; lustre strong metallic ; co- lour iron-black ; streak brown. B.B. acts like peroxide of manga- nese. Soluble in hydrochloric acid with escape of chlorine. The powder colours concentrated sulphuric acid bright-red in a short time. Chem. com. Mn + fan? with 31 protoxide and 69 peroxide of man- ganese, or 72-4 manganese and 27'6 oxygen. Analyses. Manga- bxy- nese.* gen. Baryta. Silica. Watr. Total. 1 98-90 10-22 2 92-49 |7'00 o-Ji 0-15 0-34 0-43 100 99-64 Turner, Ihlefeld, Harz. Rammelsberg, Oehrenstock near Ilmenau. * In (1) protoperoxide ; in (2) protoxide. Hausmannite is rather rare, but occurs with other manganese ores at the above localities, and, it is said, at Leisa near Marburg and Schneeberg in the Erzgebirge. Allan adds Framont in Alsace, and Dana, Lebanon in Pennsylvania. 360. BRAUNITE, Haidinger, Phillips ; Hartbraunstein, Hausmann ; Brachytype Manganese Ore, Mohs. Tetragonal; P 108 39', consequently almost an octahedron. The usual forms are P and P . OP. The crystals often very small, arid united in druses or granular aggregates. Cleavage, pyramidal along P rather perfect. Fracture uneven ; brittle. H. = 6 6'5 ; G- = 4-818. Opaque ; lustre imperfect metallic ; colour and streak dark brownish-black. B.B. infusible alone ; with fluxes shows reaction for manganese. Soluble in hydrochloric acid, evolving chlorine. Chem. com. peroxide of manganese nin, with 70 manganese and 30 oxygen ; or by Turner's analysis of a variety from Elgersburg, 67 '44 manganese, 29'35 oxygen, 2'62 baryta, 0*95 water, and trace of silica (= 100). It occurs at Elgersburg, Oehrenstock, and Friedrichsroda in Thu- ringia in quartzose porphyry ; and also near Ihlefeld, Schmalkald, Leimbach in Mansfeld, and Neuenkirchen in Westphalia. Marceline of Beudant from St Marcel was considered distinct, but Descloiseaux has found its crystallization to agree with braunite. The Heterocline of Breithaupt, from the same locality, said to form monoclinohedric pyramids with faces meeting at 109 36', is very si- milar. It is iron-black, with brownish -black streak. G-. = 4'652 ; H. =- 5. The following are analyses of these minerals. Family,'] PSILOMELANE. 423 Mang. perox. Iron perox. Silica. Lime. Magnesia, &c. Total. 1 2 3 68-fi3a 85-87 75-80 11-49 3-39 4 14 10-24 10-16 15-17 1-14 0-61. 0-26 0-44 b 2-80 c 98'9ti 100-47 97-91 Damour, Marceline, G. 475. Ewreinoff, Heterocline. Berzelius, Do. (a) Protoxide + 7'20 oxygen ; (b) potash ; (c) alumina. Berzelius gives Mn 3 si for the substance lie analyzed ; but they seem rather impure mixtures of braunite ; compare Rhodonite, p. 211 361. PSILOMELANE, Haidiuger, Phillips; Schwarzeisenstein, Werner ; Uucleavable Manganese Ore, Mohs. Cryptocrystalline or amorphous. It forms botryoidal, reniform, or stalactitic masses, with smooth, rough, or granular surfaces, and rarely showing traces of a fibrous texture, more often only a foliated structure. It also occurs massive and disseminated. Fracture con- choidal or uneven. H. = 5'5 6 ; Gr. = 4*1 4-2. Opaque ; lustre dull or glimmering ; colour iron-black or bluish-black ; streak brown- ish black and glistening. In the closed tube yields water. B.B. infusible alone ; with fluxes acts like peroxide of manganese. The powder colours concentrated sulphuric acid red ; and the varieties containing barytes furnish a copious white deposit. Analyses. [ Mang. proto- perox. Oxy- gen. Ba- ryta. Pot- ash. Copper protox. Silica. Watr. Total. 1 69-80 2 70-97 3 81-8 4 81-36 5 70'60a 6 77'23a 7 83-3 8 70'l7a 7-36 7-26 9-5 9-18 14-18 15-82 98 15-16 lfi-3!) 16-69 6*55 0-12 5-8 808 4*5 3-04 4-05 5-29 2-62 096 040 ! 30 0-26 0-95 0-54 0-60 C-52 0-90 6-22 4-13 4-2 3-396 l-67c ... d 4-3 e 1-43/ 100 100 100 100-61 99-47 100-29 99-1 1UO Turner, Schneeberg. Do. Roroaneche. Fuehs, Baireuth. Rammelsberg, Horhausen. Ebelmen, Gy, Haute-Saone. Clausbruch, Ilmenau. Scheffler, Do. Rammelsberg, Heidelberg. (a) Protoxide ; (b) + 1-43 iron peroxide, 0-38 lime, and 0-32 soda and magnesia ; (c) + 1-05 magnesia and 077 iron peroxide ; (d) + 0-91 lime ; (e) + 1'8 lime, 2-1 alumina, and 0-3 iron peroxide ; (/) + 0'60 lime, 0'21 magnesia, and 0'54 cobalt protoxide. Turner considered psilomelane as a compound of peroxide of man- ganese and baryta, the hyperoxide of manganese arising in a mixture of pyrolusite. Rammelsberg again gives the general formula M Q Mn + k or 3 ii, with part of the protoxide replaced by potash or baryta (so that potash and baryta psilomelanes might be distinguished), or by magnesia and protoxides of copper or cobalt. On this view a great part of the hyperoxide is merely mixed. Thus, in 424 CREDNERITE CUPREOUS MANGANESE. [Manganese Ores Manganese Manganese-hyperoxide protoxide. combined. mixed. No. 1 ... 10-53 ... 44-21 ... 22-41 No. 4 ... 9-50 ... 32-72 ... 48'30 No. 6 ... 6-87 ... 30-24 ... 56'55 No. 8 ... 4-68 ... 30-02 ... 50'17 It seems thus rather a mixture than a simple mineral. Besides the above localities, psilomelane occurs in Devonshire, Cornwall, Ver- mont in North America, and many other places, generally with ores of manganese. 362. CREDNERITE, JV. ; Mangankupferoxyd, Hausmann. Monoclinohedric ; dimensions unknown. Occurs in crystalline granular, foliated aggregates ; sometimes in concentric layers with pyrolusite and hausinannite. Cleavage, basal very distinct, pris- matic, along the sides of a clmorhombic prism imperfect ; H. = 4-5 5 ; G. = 4-89 5'07. Opaque ; lustre metallic ; colour iron- black ; streak brownish-black. In the closed tube gives no water. B.B. infusible, but exfoliates ; with soda yields copper ; with borax in the inner flame forms a glass first green, then copper-red and enamel-like, and at length, especially with tin, colourless and trans- parent. Nitric acid dissolves the copper protoxide. In nitrochloric acid it forms easily a green solution. Chem. com. nearly 3 c u + Mn Mni or, by Credner's analysis, 43-85 copper protoxide, and 55*73 protoperoxide of manganese (= 99-58). It occurs at Friedrichsroda in Thuringia with ores of manganese, the volborthite and earthy ma- lachite. 363. CUPREOUS MANGANESE, Phillips ; Kupfermanganerz, Brei- thaupt; Uncleavable Brithyne-Allophane, Mohs. Amorphous ; botryoidal, stalactitic, or encrusting. Fracture con- choidal or earthy ; rather brittle or friable ; H. = 3-5 or less ; G. = 3-1 3"2. Opaque; vitreous lustre; colour black, inclining to brown or blue ; streak similar. Give off much water in the closed tube. B.B. fusible, and yield copper ; with fluxes show reaction for copper and manganese. Analyses. Cheni. -com. (MH cu) Mn 2 + 2 k, Ratnmelsberg. Mang. perox. Oxy- gen. Copper protox. Iron perox. Ba- ryta. Lime. Watr. Silica. Po- tash. Total. 1 7410 2 49-99& 3 532-2b 4 30-05 8 : 91 9-14 4-80 14-67 1685 11-51 0-12 4-70 1-88 28-29 1-64 1-69 2-25 2-85 20-10 14-46 16-94 29-45 0-30 274 ...a 0-52c 0-64d 100-47 101-06 103-34 100 Kersten. Rammelsberg. Bottler. Du Menil. (o) + T05 gypsum; (6; protoxide; (c) + 0-19 magnesia and 0'49 protoxides of cobalt and nickel ; (d) + 0-14 protoxide of cobalt and nickel. Family.'] EARTHY-COBALT WAD. 425 No. 1 is from Schlackenwald ; Nos. 2, 8 from Camsdorf near Saal- feld ; No. 4 the Black Copper of Phillips (Kupferschwarze, Werner) from Lauterberg in the Harz. They are evidently very impure mix- tures, and are rather the results of decomposition than distinct species. Similar substances are common in many of the copper mines in Corn- wall, the Harz, Silesia, and Siberia. 364. EARTHY-COBALT, Phillips; Schwarzer Erdkobalt, Werner; Uncleavable Psylomelane-Graphite, Mohs. Amorphous, reniform, stalactitic, or investing, also massive and dis- seminated. Fracture conchoidal or uneven ; sectile; H. = 1 1*5; G. = 2*1 2 -2. Opaque ; lustre dull or glimmering ; bluish or brownish-black ; streak black, shining, and leaves a mark. It gives out water in the closed tube. B.B. infusible alone, but colours borax glass violet in the outer, smalt-blue in the inner flame. Chem. com. (CQ, cu) Mn 2 + 4 H according to Rammelsberg, who found 40*05 manganese protoxide, 9'47 oxygen, 19*45 cobalt protoxide, 4*35 copper protoxide, 4-56 iron peroxide, 0*50 baryta, 0*37 potash, and 21*24 water (= 99*94) in a very pure variety from Camsdorf near Saalfeld. He considers the iron peroxide with 0*52 water as a mix- ture of limonite. The analyses of Klaproth and Dobreiner were imperfect, and the mineral seems rarely pure, being probably a mere product of decom- position. It occurs also at Glucksbrun in Thuringia, Riechelsdorf in Hessia, in the Lauzitz ; the Ural ; and at Alderley Edge in Cheshire in sandstone, with lead and copper. It is only used in the prepara- tion of smalt. The Horncobalt from Siegen seems a mixture of this mineral with quarz. 365. WAD, Karsten, Allan ; Earthy Manganese, Phillips ; Mangan- schaum, Hausmann ; Schaumartiger Wad-Graphit, Mohs. Massive ; and forming reniform, stalactitic, or arborescent froth-like crusts, or masses sometimes with curved laminar divisions. Fracture conchoidal or even, with a fine, scaly, earthy, or compact surface ; very soft and sectile, but some varieties brittle, with H. = 3 ; G. = 2*3 3'7 ; but from its loose porous texture feels very light, and even swims on water. Opaque ; lustre semimetallic, and shining or dull ; colour and streak brown or black. It gives out water in the closed tube. B.B. acts like peroxide of manganese. Almost wholly soluble in hydrochloric acid. Chem. com. veiy uncertain, but on the whole Mn (ca, Ba, K) Mn 3 + 3 H, mixed with M n , Rammehberg. Analyses, next page. 426 COBALT-OCHRE. {Ochres. Mang. prot. Oxy- gen. Watr. Bary- tes. Lime. Iron perox. Silica, &c. Total. 1 2 3 4 5 6 7 79-12a 38-596 62-4 68-9 66-5 67-50 82-516 8-82 12-8 l]-7 12-1 13-48 10-66 10-29 15-8 12-4 9-8 10-30 5-58 1-40 5-40 s'-'i 03f> 4-22 1-91 52-34 6-0 l"6 1-01 0-77 2-74c 3-0 d 7*0 d 2-5 0-47<; 1-43/ 100 109-36 100 100 100 100 99-19 Turner, Upton Pyne, Devon. Do. Derbyshire Berthier, Groroi. Do. Vicdessos. Scheffler, Ilmenau. Rammelsberg, Harz. IgeJstrom, Westgothland. (a) Protoperoxide; ( b) peroxide; (c) earthy matter; (d) alumina; (e) + 3-65 potash ; (/) + 6'30 alumina and 0'69 magnesia. Wad is often a result of the decomposition of carbonate of iron or other ores, and is a very common mineral, though rarely occurring in large masses. It is found in beds, veins, and fissures, or colouring the surface, and forming dendritic delineations on rocks of various kinds. Some of its chief localities are Elbingerode and Iberg in the Harz ; Kemlas andArzberg in Franconia ; Siegen, Nassau, Piedmont, and Vicdessos and other places in France. The ochrey variety occurs near Exeter in Devonshire and in Cornwall. The variety from Groroi in Mayenne is the Groroilite of Berthier, but is not a distinct species. Wad is used chiefly as a coarse pigment in oil painting ; also for colouring and glazing pottery, and in the manufacture of glass. When mixed with linseed oU, the ochrey variety often takes fire spontaneously. Newkirkite of Thomson, found in small four-sided acicular crystals on a fibrous red haematite from Neukirchen in Alsace, seems a con- nected mineral, but is still imperfectly known. It has a brilliant black colour ; splendent metallic lustre ; H. = 3 8*5 ; G. = 3'824 ; and consists, according to Muir's analysis, of 56 '30 binoxide of mangan- ese, 40-35 peroxide of iron, and 6-40 water (= 103'35). OCHRES. The following substances, chiefly products of decomposition, may be described here as an appendix to the foregoing families of oxidized ores. 366. COBALT-OCHRE, N.; Earthy cobalt, Phillips; Erdkobalt, Hausmann. Amorphous, encrusting, or disseminated. Fracture earthy. H.=l Ochres.'] MOLYBDENA, BISMUTH, AND ANTIMONY OCHRES. 427 2 ; G.= 2 2-65. Colour yellowish -grey or brown to liver-brown ; streak brown or yellowish-grey and shining. In the closed tube yields water. B.B. emits odour of arsenic, and fuses to a black magnetic slag ; with borax forms a smalt-blue glass. According to Ramnielsberg, it is a mixture of hydrous arseniate of iron protoxide, cobalt peroxide, lime, and a little antimony. It is a product of decomposed smaltine ; and occurs at Camsdorf and Saalfeld in Thuringia, Riechelsdorf In Hessia, Allemont in Dauphine, and other localities. 367. MOLYBDENA- OCHRE ; Molybdanocher, Karsten ; Oxide of Molybdena, Phillips. Fine earthy and friable ; incrusting or disseminated. Opaque, dull ; straw, sulphur, or orange-yellow. B.B. on charcoal fuses and smokes ; with soda is reduced to a grey metallic powder ; with borax acts like molybdic acid. Soluble in hydrochloric acid, the solu T tion being coloured blue by iron. It is essentially MO, or molyb- dic acid with 66'6 molybdena and 33'4 oxygen (or, according to the recent investigations of Svanberg and Struve, 65-71 molybdena and 34-29 oxygen). It seems a product of molybdanite, with which it oc- curs in granite or gneiss, as at Linnas in Smoland, Bispberg in Swe- den, Numraedal in Norway, in the Pfalzer Thai in the Tyrol, and on Corybuy near Loch Creran in Scotland. 368. BISMUTH-OCHRE, Allan; Wismuthocher, Werner; Oxide of Bismuth, Phillips ; Bismuth oxide, Hauy. Occurs massive and disseminated, or earthy and pulverulent. Very soft and friable. G. *= 4'36 4*7. Opaque ; dull or glimmering ; straw-yellow to light-grey or green. B.B. acts like bismuth peroxide ; on charcoal is easily reduced ; easily soluble in nitric acid. Chem. com. BI , or peroxide of bismuth, with 89-87 bismuth and 10*13 oxy- gen, but sometimes mixed with a little iron, copper, or arsenic. It arises generally from the oxidation of bismuth with which it occurs at Sclmeeberg and other localities in the Erzgebirge, in Siberia, and St Agnes in Cornwall. In an earthy steatitic mineral from the last locality, Macgregor found 28'8 bismuth oxide, 51 '3 carbonic acid, 2-1 iron peroxide, 7'5 alumina, 6'7 silica, and 3'6 water. It seems evidently a mere mixture. 369. ANTIMONY-OCHRE; Antirnonial ochre, Phillips; Antimoine oxide, Hauy; Spiess-glanzocher, Hausmann, Mohs. Occurs massive, disseminated, and as a pulverulent crust ; also in pseudomorphs after antimonite. Fracture uneven and earthy. Soft and friable. G. = 3'7 3-8. Opaque ; dull or glimmering, with 428 TUNGSTEN-OCHRE URANIUM -OCHRE MINIUM. [Ochres. glistening streak ; colour straw, sulphur, or ochre -yellow, yellowish- grey or white. In the closed tube yields water. B.B. is not reduced, but forms a stain on the charcoal. Easily reduced with soda. Chem. com., probably antimonious acid, {, , with water. It occurs with an- timonite at Wolfsberg in the Harz, Kremnitz in Hungary, in Saxony, France, Spain, and at Padstow in England. 370. TUNGSTEN-OCHRB ; Wolframocher, Hausmann ; Scheelsaure, Naumann. Occurs earthy and disseminated, or forms pulverulent incrustations. Soft. Opaque, dull, yellow or yellowish-green. B.B. on charcoal in the reducing flame, becomes first blackish-blue and then black ; with fluxes acts like tungstic acid. Wholly soluble in caustic ammonia. Chem. com. tungstic acid w, with 80 tungsten and 20 oxygen. It is found with wolfram in a quartz vein at Huntington in North Ame- rica. 371. URANIUM-OCHRE ; Uran ochre, Phillips, Werner ; Urane oxide terreux, Hauy Occurs massive, disseminated or incrusting. Fine earthy or fibrous. Sectile, soft, and friable. Opaque, dull, or glimmering. Straw, sul- phur, or orange-yellow. In the closed tube yields water, and be- comes red. B.B. in the reducing flame becomes green, but does not fuse ; with salt of phosphorus forms in the oxidating flame a yellow, in the reducing flame a fine green glass. Easily soluble in acids. Chem. com. probably u', with water in uncertain amount. It occurs with pechurane at Joachimsthal in Bohemia, Johann-Georgenstadt in Saxony, and at St Symphorien in France in granite. 372. MINIUM (Native), Phillips ; Mennige, Hausmann ; Plomb oxide' rouge, Hauy. Occurs massive, disseminated, or investing ; also as a pseudomorph after cerussite and galena. Fracture even or flat, conchoidal and earthy ; H. = 2 3 ; G. = 4'6. Opaque, dull or weak resinous inclining to pearly. Colour aurora-red, streak orange-yellow. B.B. heated gently it becomes darker, and on ignition yellow, and fuses easily, being reduced to lead on charcoal. In hydrochloric acid loses its colour, and is changed into chloride of lead ; soluble in nitric acid, which leaves the brown hyperoxide. Chem. com. probably that of the artificial minium, or pb + 2 pb, with 90*7 lead and 9-3 oxygen. Minium is often a produce of the decomposition of other lead ores, sometimes, as at the Schlangenberg in Siberia, from the action of fire. It also occurs at Badenweiler, Bleialf in the Eifel, in Anglesea Ochres.'] LEAD-OCHRE CHROME-OCHRE TELLURITE. 429 in veins in clay slate, and at Grassington moor and Weirdale in Yorkshire. It is a not uncommon product of metallurgic processes, and many so-called native miniums have been formed in this manner. ^.. 373. LEAD-OCHRE ; Plumbic ochre, Dana ; Bleiglatte, Hausmann ; Giatte, Naumann. Massive ; G. = 8*0. Opaque, dull, sulphur or lemon-yellow. In other respects similar to the artificial yellow oxide of lead, or p'b with 92-8 lead, and 7*2 oxygen. According to von Geralt, it occurs among the volcanic products of Popocatepetl in Mexico. John examined another supposed natural lead-ochre from Eschweiler, which con- tained 93*27 lead protoxide, 3*85 carbonic acid, 0*48 peroxide of iron and lime, 2-40 silica, with iron peroxide and a trace of copper protoxide (= 99 -90). 374. CHROME-OCHRE, Hausmann ; Oxide of Chrome, Phillips. Occurs in loose earthy masses, disseminated or investing. Frac- ture earthy. Opaque or translucent on the edges ; dull ; colour grass-green to siskin or yellowish-green. B.B. infusible ; with borax forms an emerald-green glass. Soluble to a green fluid in solution of potash. Chem. com. perhaps cr or oxide of chrome, with 68*65 chromium, and 31-35 oxygen, but rarely pure. It occurs in fissures of chromite on Unst in Zetland. In general the chrome oxide is so mixed with the rock as only to be separable by chemical means, when it is sometimes named chrome-stone. In such a mixture from Creuzat in France, Drappiez found 13 per cent, chrome oxide, with 52 silica, 27 alumina, 4*5 lime, and 2 iron peroxide ; Zellner, in a variety fromWaldenburg in Silesia, only 2 per cent, chrome oxide ; and Hisinger, in a clay from Mortenberg in Sweden, 10 per cent, protoxide of chrome. The chrome-ochre from the porphyry of Halle is a product of its decomposition, and is on the whole merely a kaolin, with part of the alumina replaced by chrome oxide. Wolff" found, on a mean of two analyses, 46*11 silica, 30*53 alumina, 3*15 iron peroxide, 4*28 chrome oxide, 3*44 potash, 0*46 soda, and 12*52 water (= 100-49). It has G. = 2*701, and is scarcely affected by hydrochloric, but de- composed by sulphuric acid. Wolchonskoite, an emerald or blackish-green massive mineral from Okhansk in Perm, is a similar mixture, with more chrome oxide ; Berthier having found 34 per cent., Kersteu 17*93, and Ilimoff 31*24 per cent, of chrome oxide. 375. TELLURITE ; Tellurium -ochre, Petz. Occurs in very small spherical masses with a radiated fibrous 430 CUPRITE CHALCOTRICHITE. [Red Copper Ore structure. Colour yellowish or greyish -white. B.B. on charcoal and in the open tube acts like telluric acid f e . It occurs very rarely at Facebay and Zalathna in Siebenbiirg. IV. FAMILY. THE RED COPPER ORES. 376. CUPRITE, Haidinger ; Red Copper Ore, Allan , Red oxide of copper, Oxydulated Copper, Phillips ; Rothkupfererz, Wer- ner; Cuivre oxidule, Hauy; Octahedral Copper Ore, Mohs. Tessera! ; the most common forms are O, ocO, and ccO ; faces of 2O, 2O2, and other forms, more rarely appear. The crystals are seldom imbedded, usually attached and combined in druses. It also occurs in granular or compact aggregates. Cleavage, octahedral rather perfect. Brittle. H. = 3-5 4 ; G. = 5-7 6. Translu- cent or opaque ; lustre metallic-adamantine ; colour cochineal and other shades of red, sometimes with a lead-grey tarnish ; occasionally crimson in transmitted light. Streak brownish-red and shining. B.B. on charcoal becomes black, fuses quietly, and forms a grain of copper. In the forceps colours the flame pale-green, and, moistened with hydrochloric acid, a fine blue. Soluble in hydrochloric or nitric acid, and in ammonia. Chem. com. cm with 88-9 copper and 11 -1 oxygen. Klaproth, in a foliated variety from Turjinsk, Siberia, found 91 copper and 9 oxygen, probably by an error ; Chevenix, in that from Cornwall, 88'5 copper and 11-5 oxygen. Cuprite occurs in beds or veins, especially in granite, the crystal- line schist and transition rocks, along with other ores of copper, and galena, blende, and pyrites. It occurs in great abundance, and in fine crystals, in Siberia, the Bannat, and Cornwall in the Wheal Gor- land, Wheal Muttrel, Carvath, and United mines. Fine crystals also occur at Chessy near Lyons, Linares in Spain, in Cuba, and in several places both in North and South America. It has also been found encrusting some slags ejected by Vesuvius. 377. CHALCOTRICHITE, Glocker ; Capillary Red oxide of Copper, Phillips; Kupferbliithe, Hausmann. Rhombohedric, R 99 15' ; usual form ooR . OR. It occurs in fine capillary crystals, grouped in bundles or reticulated. Cleavage, rhombohedric along R perfect. G. = 5'8. Colour cochineal and crimson red. In chemical and other characters agrees with cuprite. Occurs at Rheinbreitenbach, Moldawa, and at Wheal Goiiand, Car- harrack, and St Day in Cornwall. Family.'] TENORITE ZINCITE. 431 Snckow first pointed out the distinct crystallization of this mineral. Kersten found selenium in a specimen from Rheinbreitenbach ; but v. Kobell and others have sought for this substance without success. It seems, therefore, like cuprjte, the simple suboxide of copper, which is consequently dimorphous. The Tile ore (Ziegelerz, Werner, Kupferbraun, Hausmann) is red- dish-brown, or brick-red and earthy. It consists of suboxide of cop- per, mixed with much peroxide of iron and other substances, and is found ir the Bannat, Thuringia, Cornwall, and on Llanymynech hill in Shropshire. 378. TENORITE, Semmola. Hexagonal, forming thin tabular crystals from | to 5 lines in dia- meter attached by the edge. It is also found fine scaly or earthy. In thin folia?, translucent and brown ; lustre metallic ; colour dark steel-grey or black. It is a natural protoxide of copper, c'u = 79 '83 copper and 20 '17 oxygen ; and occurs in fissures of lava in one of the smaller craters on Vesuvius. 379. ZINCITE, Haidinger ; Zinc oxide ferrifere, Hauy ; Red Oxide of Zinc, Phillips ; Red Zinc, Jameson ; Zinkoxyd, Hausmann ; Prismatic Zinc Ore, Mohs. Hexagonal ; but only found disseminated in crystalline, granular, or foliated aggregates. Cleavage, basal and prismatic along coP both very perfect ; also a laminar structure parallel to the basis. H. = 4 4*5 ; G. = 5'4 5 '5. Translucent on the edges ; lustre adaman- tine ; colour blood or hyacinth-red ; streak orange -yellow. B.B. in- fusible, but phosphoresces, and on charcoal, especially with soda, forms a coating of zinc. With borax and salt of phosphorus shows reaction for manganese. Chem. com. probably zn, with 80'26 zinc and 19 '74 oxygen. Bruce found 8 per cent, peroxide of manganese and iron ; Berthier 12 per cent, protoperoxide of manganese ; Whit- ney, in one variety, 94 45 zinc oxide, with trace of manganese, and 4-49 of mixture of franklinite ; in another, 96'] 9 zinc oxide, 3 '70 man- ganese peroxide, and 10 magnetic iron ; Hayes, 93'5 zinc oxide, 5 '5 manganese protoxide, and 0-4 peroxide of iron. It occurs with franklinite and calc-spar at Franklin and Sterling in New Jersey, and is a good ore of zinc. Minute hexagonal prisms, terminated by pyramids, of this mineral, have been observed in the zinc furnaces near Liege, and in many iron furnaces, as those of Konigshiitte in Silesia. 432 VALE NTINITE ARSENiTE. [ White Antimony Ore V. FAMILY. THE WHITE ANTIMONY ORES. 380. VALENTINITE, Haidinger ; White Antimony, Jameson ; Oxide of Antimony, Phillips; Weiss -Spiessgiaserz, Werner; Anti- monbliithe, v. Leonhard ; Prismatic Antimony-Baryte, Mohs. Rhombic ; ooP 137, Poo 7;:i. - ''% 390- AMALGAM ; Native amalgam, Phillips ; Mercure argental, Hauy ; Dodecahedral Mercury, Mohs. Tesseral; sometimes very beautifully crystallized, especially the rhombic dodecahedron o>O, variously combined with 202, O, ooOoo, 3O|, and ooO3. It is also found compact, disseminated, or forming crusts and plates. Cleavage, sometimes in traces along ooO, but in general only the conchoidal fracture visible. Rather brittle. H. = 3 3*5 ; G. = 13'7 14*1. Colour silver-white, and gives the same colour to copper when rubbed upon it. In the closed tube yields mercury and leaves silver. Easily soluble in nitric acid. Chem. com. sometimes Ag Hg 2 , with 35 per cent ; sometimes Ag Hg 3 , with 26'5 per cent, silver. Analyses. Silver. Mercury I Total. 1 2 3 4 25-00 36-00 27-60 86-49 7330 98-30 64-00 100 72 50 100 13-51 100 Heyer, Moschellandsberg. Klaproth, Do. Cornier, Allemont ? Domeyko, Arqueros, Chile* 442 ANTIMONY ARSENIC -ANTIMONY ARSENIC. [Native Amalgam occurs chiefly in the quicKsilver mines at Morsfeld and Moschellandsberg in Rhenish Bavaria, and at Szlana in Hungary ; also, it is said, at Salberg in Sweden, Allemont in Dauphine, and Almaden in Spain. No. 4, the arquerite of Domeyko, forais the chief ore in the rich silver mines of Arqueros near Coquimbo. It occurs in small octahedral crystals, and arborescent forms, is ductile and mal- leable ; H. = 2 2-5 ; G. =- 10 8. Its chem. com. is Ag 6 Hg, and B.B. it acts like amalgam. 391. ANTIMONY ; Native A., Phillips ; Gediegen Spiesglass, Wer- ner; Antimon, Naumann; Antimoine natif, Hauy ; Rhom- bohedral Antimony, Mdhs. Rhombohedric, R 117 15', but very rarely occurs crystallized, ge- nerally massive and disseminated ; sometimes in spherical, botry- oidal, and reniform aggregates, with a granular texture. Cleavage, basal highly perfect, rhombohedral along R perfect, and along 2R imperfect. Fracture not perceptible. Rather brittle and somewhat sectile. H. = 3 3'5 ; G. = 6-6 6-8. Tin-white, with a grey- ish or yellowish tarnish. B.B. easily fusible, and on cooling crystal- lizes in rhombohedrons ; on charcoal burns with a weak flame, and volatilizes, forming a white deposit. In the closed tube yields a white sublimate. Chem. com. antimony, usually with a small amount of silver, iron, or arsenic. In a specimen from Andreasberg, Klaproth found 98 antimony, 1 silver, and 0-25 iron. This mine is its principal European locality, but it also occurs at Przibram in Bohemia, and formerly at Sala in Sweden, and Allemont in Dauphine. It is also known in Mexico and Borneo. 392. ARSENIC-ANTIMONY ; Arsenical antimony, Phillips ; Antimon- arsen, Naumann ; Arsenikspiessglanz, Molts. Rhombohedric ; in spherical or reniform masses, with a curved lamellar structure, and a granular or almost compact texture. H. = 3'5 ; G. = 6*1 6*2. Colour tin-white, approaching to lead-grey, and more or less tarnished with brownish-black. B B. gives out a strong smell of arsenic. Chem. com. Sb As 3 , according to Ram- melsberg's analysis of the variety from Allemont, 37'85 antimony and 62*15 arsenic. But the two elements are isomorphous, and form no definite compound, as Steinmann and others have shown. Its chief locality was formerly Allemont in Dauphine ; also Przibram in Bo- hemia, Schladming in Styria, and Andreasberg in the Harz. 393. ARSENIC ; Native Ar., Phillips ; Arsen, Naumann ; Arsenic natif, Hauy ; Rhombohedral Arsenic, Molis. Rhombohedric ; R 114 26'. The forms known are OR, R, 2R Metals."] TELLURIUM. 443 Fig. 239. 85 26' (fig. 239), but seldom distinctly crystallized. It usually occurs in fine granular, almost compact, or rarely columnar aggregates, or botryoidal, reniform, or spherical, With a curved lamellar structure ; also mas- sive and disseminated. Cleavage, basal perfect, rhombohedric along K and 2R imperfect. Fracture uneven and fine granular. Brittle. H. = 3-5 ; G. = 57 5-8. Whitish lead-grey on the fresh fracture, but in a few hours acquires a greyish-black tarnish. When broken or heated, gives out arsenical odours. B.B. easily fusible, but on charcoal gives off dense white vapours, and may be wholly volatilized without fusing. In the closed tube forms a metallic sublimate. With nitric acid changes into arsenious acid. Chem. com. arsenic, with some antimony, and traces of iron, silver, or gold. In specimens from Joachimsthal, John found 2 3 per cent, antimony, with 1 per cent, of iron peroxide and water. Arsenic occurs chiefly in veins in the crystalline and transition strata, with ores of antimony, silver, and lead ; as at Andreasberg in the Harz ; Annaberg, Schneeberg, Marienberg, and Freiberg in Saxony ; Joachimsthal in Bohemia ; Eapnik in Siebenburg ; Orawitza in the Bannat ; Allemont in Dauphine ; St Marie aux Mines in Alsace ; and Kongsberg in Norway. Also at Zmeoff in the Altai ; in New Hampshire in North America, and in Chili. In a damp atmosphere arsenic soon tarnishes, and in a few days is covered with a dark coat of the suboxide. Pulverized and moistened, it undergoes spontaneous combustion. It has also a strong tendency to combine with other metals. At Kongsberg it combines thus with silver, and at Andreasberg with antimony and silver ; both compounds being named Arsenic-silver. Breithaupt's Arsenic- glance, from Palmbaum near Marienberg, contains, according to Kersten, 97 arsenic acid and 3 bismuth, and is probably a similar mixture. It has a columnar structure, with a perfect cleavage in one direction. H. = 2 ; G. 5'36 5'39. Colour dark lead- grey. It takes fire at the flame of a candle, and burns. Arsenic is used in various pharmaceutical pre- parations and metallurgic processes, but is usually injurious when mixed with ores. It is almost constantly found in iron ores and iron, and Schaf ha'utl considers its presence as one cause of the excellence of the Danemora iron, contrary, however, to the common opinion. 394. TELLURIUM; Gediegen Silvan, Werner; Rhombohedral Tellurium, Mohs. Hexagonal ; P 115 12'. It is rarely crystallized, in the form ooP . OP . P ; usually found massive or disseminated, and fine gra- nular. Cleavage, prismatic along ooP perfect, basal imperfect ; 444 LEAD TIN. [Native slightly sectile. H. = 2 2-5 ; G. = 6'1 6'3. Tin-white. B.B. very easily fusible ; burns with a greenish flame and much smoke, which forms a white ring with a reddish margin on charcoal. In the open tube burns with a greenish-blue flame, and forms a white subli- mate, which can be fused to clear colourless drops. The vapour has often a smell of raddish from selenium. Soluble in nitric acid with evolution of nitrous vapours ; and in concentrated sulphuric acid forms a bluish-red solution. Chem. com. tellurium, with a little gold or iron. Analyses. v 2 ' Tellu- rium. Gold. Iron. Sulphur. Total. 92-55 97-22 0-25 2-78 7-20 trace trace 100 100 Klaproth. Petz. Occurs along with quartz, iron pyrites, and gold, at Facebay near Salathna in Siebenburg, where it is melted for the gold it contains. It has also been quoted, but probably erroneously, from Norway and Connecticut. 395. LEAD; Native L., Phillips; Blei, Naumann ; Plomb natif volcanique, Hauy. Tesseral, but not observed crystallized ; only capillary, filiform, or branched, and in thin plates or disseminated. Ductile and malleable. H. = 1-5 ; G. = 11-3 11-4. Colour bluish-grey with a blackish tarnish. B.B. very easily fusible ; on charcoal volatilizes and forms a sulphur-yellow coating. Soluble in nitric acid. Chem. com. lead. 'Found in considerable abundance by Rathke in vesicular cavities of lava on the island of Madeira. The specimens found by Launoy in the deserted mines of Carthagena in Spain are more doubtful. It is also said to occur in galena on the Anglaise river in Ohio. Allan observed it in globules in galena at Alston Moor, but seems doubt- ful of its genuineness. It is also noticed from the carboniferous lime- stone near Bristol, and at Kenmare in Ireland. 396. TIN. This metal has not certainly been found native, though quoted by Rom4 de ITsle from Cornwall, and by other authors from France and Hindostan. The fused metal crystallizes in regular octahedrons. Frankenheim obtained it in tesseral forms when reduced at low tempe- ratures ; Breithaupt from the Cornwall furnaces in hexagonal prisms ; whilst Miller describes that formed by galvanic action as tetragonal. Metals.'] BISMUTH COPPER. 44$ 397. BISMUTH; Native B., Phillips ; Gediegen Wismtith, Werner; Bismuth natif, Hauy ; Octahedral Bismuth, Mohs. Tesseral ; O, ocO, 40 ; the crystals are often mis-shapen, or ren- dered indistinct by their union in groups. It also occurs arborescent, feathery, or reticulated ; rarely filiform or in plates ; often massive or disseminated and granular. Cleavage, octahedral perfect. Not malleable. Very sectile. H. = 2-5 ; G. = 9'6 9*8. Colour red- dish silver-white, often with a yellow, red, brown, or parti-colour tarnish. B.B. very easily fusible, even in the flame of a candle. On charcoal volatilizes, leaving a citron-yellow coating. Soluble in ni- tric acid ; much water throws down a white precipitate from the so- lution. Chem. com. bismuth ; sometimes with a little arsenic. Bismuth is found in granite and the crystalline slates ; in the tran- sition strata, and in the Kupferschiefer, chiefly with ores of cobalt and of silver. Its most important localities are the Saxon Erzgebirge at Schneeberg, Annaberg, Marienberg, Johann- Georgenstadt, and Al- tenberg ; Joachimsthal in Bohemia ; Bieber in Hanau ; Friedrichs- roda in Thuringia ; and Wittichen in the Schwarzwald. Also at Modum in Norway ; Fahlun in Sweden ; St Collumfy Bottallach, and Wheal Sparnon near Kedruth in Cornwall ; Carrack Fell in Cum- berland; and formerly at Alva in Stirlingshire. Lane's mine in Connecticut is its only locality in the United States. 398. COPPER ; Native C., Phillips ; Kupfer, Naumann^ Cuivre natif, Hauy; Octahedral Copper, Mohs. Tesseral ; O, ooOco , ooO, ooO2, alone or combined. The crys- tals are small, and generally irregular, deformed, and grown together. Macles united by a face of O. Often occurs filiform, moss-like, and arborescent ; or in plates and laminae ; also investing, massive, and disseminated ; rarely in loose grains or lumps. Cleavage, not per- ceptible. Fracture hackly. Malleable and ductile ; H. = 2'5 3 ; G. = 8'5 8' 9. Colour copper-red, with yellow or brown tarnish. B.B. rather easily fusible, colouring the flame green. Readily soluble in nitric acid ; and in ammonia with the access of air forms a blue solution. Chem. com. copper, rarely with a little iron or other metals. Copper occurs in beds and veins, or disseminated in granite, ser- pentine, and the crystalline schists, in the transition and secondary strata. Its chief localities are Cornwall, as at Wheal Unity, Mullion, Camborne, St Just, Poldory, and the Lizard ; at Chessy near Lyons, the Bannat and Hungary in Europe. Siberia, China, Japan in Asia ; in Canada, the United States, Mexico, Cuba, Brazil, and Chili. Some fine crystals occur with fibrous mesotype in amygdaloidal trap 446 IRON. [Native in Nalsoe, one of the Faroe islands. A large mass found near Lake Superior measured 4| feet long by 4 feet broad, and weighed from 3000 to 4000 Ibs., and another from the same locality 1630 Ibs. Na- tive silver adheres to both masses. A rolled mass found at Cachoeira in Bahia, now in the museum at Lisbon, weighed about 2600 Ibs. Fused copper in favourable circumstances crystallizes in regular oc- tahedrons. Seebeck states that it also forms rhombohedrons, but according to G. Rose this is not the case. It seems sometimes to be deposited in mines from water containing the sulphate, and especially on pieces of wood. 899. IRON ; Native I., Phillips ; Gediegen Eisen, Werner ; Fer natif, Hauy ; Octahedral Iron, Mohs. Tesseral ; chiefly the regular octahedron. Cleavage, probably hexahedral or also octahedral, but only in indistinct traces. Fracture hackly. Malleable and ductile ; H. = 4*5 ; G. = 7 7'8. Colour steel-grey or iron-black, often Avith a blackish tarnish. Very mag- netic. B.B. infusible, or only in thin plates with a strong heat. Soluble in hydrochloric acid. Two varieties are usually distinguished, telluric and meteoric iron. (a) TELLURIC IRON occurs in small grains and plates, or massive and disseminated. It is almost pure iron, but contains carbon, gra- phite, or occasionally some other metal, but not nickel. Klaproth analyzed a specimen of native iron from Gross Camsdorf in Thurmgia, which contained 92-5 iron, 6 lead, and 1'5 copper. It weighed 12 ounces, and part is now in the museum at Berlin, part at Gottiugen, and both Kersten and Hausmann regard it as genuine. It has a foliated structure and crystalline granular texture. Schreiber found native iron in a vein at Oule near Allemont in Dauphine. At Ca- naan in Connecticut, a vein of native iron two inches broad was ob- served in mica-slate. It contained carbon or graphite between the laminae (91'Siron and 7'0 carbon, SheparcT). Another specimen from Penn Yan in New York, found in sandstone, contains a little carbon, but no nickel or cobalt. The iron discovered near Burlington in New York seems to be meteoric. Proust found iron in some sulphurets from South America ; and Eschwege observed it in thin, very flexible laminae in an ironstone conglomerate near Itabira do Matto Dentro in Brazil. John states that it is mixed with theplatina grains from South America. Very recently M. Molnar affirms, that he has found native iron in the gold sands at Olahpian. These sands consist chiefly of garnet, nigrine, ilmenite, and zircon, and the iron is mixed with grains of platina, the two being often attached. It also contains nickel, hitherto believed to occur only in meteoric iron. These very inte- Metals.'} IKON. 447 resting statements still require confirmation. It is also stated that native iron, with six per cent, silica and a little sulphur, has been found with galena in the veins at Leadhills. G. Rose states that the iron said to occur in tke platina sands of the Ural is derived from the tools used in washing the sand. The specimens from Kyrburg arid from Sweden, are also thought artificial. Mossier has found volcanic iron in lava at Graveneire in Auvergne, probably a natural product. It has a steel-grey or silver-white colour, foliated texture, and hackly fracture. These instances seem to prove that this metal does occasionally occur native. (6) METEORIC IRON contains nickel, along with cobalt and other metals. It is light steel-grey or silver-white, and occurs rarely crys- tallized in octahedrons, more commonly in large irregular, often cel- lular masses, or imbedded in meteoric stones. When polished and etched with acids, it exhibits linear and angular markings, or Wid- mannstatt's figures as they have been named, from which an impres- sion may be printed on paper. A great number of undoubted me- teorites have been described and analyzed. The following are a few analyses of meteoric iron. Iron. 1 93-78 2 88-04 3 88-23 4 89-78 5 85-61 6 90-88 7 66-56 8 90-24 9 83-57 10 92-58 11 W 8 Nickl. Co- balt. Cop- per. Man- gan. Magne sium. Sul- phur. Chlo- rine. Insoluble matter. Total. 3-81 1073 8-52 8-89 12-27 845 24-71 12-67 5-71 11-9 0-21 0'46 0-76 0-67 0-89 0-67 0-07a : *13 trace 0-05 0-28 trace trace ... 2-20 0-48 2-21 100 100 100 99-34 98-77 100 99-B9 100 99-54 99-69 100 Berzelius. Do. Do. Wehrle. Do. Do. Jackson. Morren. Hayes. Silliman. Stromeyer. 140 0-002 ,% 4 : UO 1 : 48 : 91 c ft traced 0-2 ... indet. 5-1 'a) With tin -f 0'04 carbon ; (b) with chromium ; is by Fig. 238. [f ], [15TJ ~- and far the most common form, then O, (9g. 238), ako others. The combinations are very nu- merous (fig. 239), and inacles are also fre- quent (fig. 240), being very characteristic- The crystals often occur imbedded singly, also united in druses and various groups, or in spheroidal, reriifonn, botryoidal, and other aggregates. Most frequently it is massive and disseminated. Clea- vage, hexahedral or octahedral, but both often very imperfect, or scarcely perceptible. Fracture conchoidal or uneven. Brittle ; H. = 6 6'5 ; G. = 4-9 5*1. Colour a peculiar bronze-yellow, pp 450 PYRITE. [Pyrites sometimes inclining to gold-yellow, at other times with a brown or Fig. 239. rig. 240. rarely variegated tarnish. Streak brownish-black. When broken, emits a smell of sulphur. Yields sulphur in the closed tube. B.B. on charcoal burns with a bluish flame, and a strong smell of sulphur. In the reducing flame fuses to a blackish magnetic bead. Soluble in nitric acid with deposition of sulphur ; scarcely affected by hydro- chloric acid. Chem com. p e " with 46*7 iron, and 53*3 sulphur. Hat- chett found 47'3 iron, and 52'7 sulphur ; Berzelius, 46*08 iron, and 53'92 sulphur. It very often contains gold, silver, or silicium, the gold occasionally in visible grains, at other times so minute as pos- sibly to be a chemical compound. Pyrite seems to be produced either by igneous action as in volcanos and certain artificial processes ; or more commonly from aqueous solution, as in mineral waters, sea water, and moors, especially under the influence of organic matter. It is also very liable to decomposi- tion. Sometimes the sulphur separates, and the iron is changed into the hydrated peroxide ; a process that occasionally takes place even in the interior of rocks, probably from the access of water, when the sulphur escapes as sulphuretted hydrogen. At other times it is con- verted into sulphate of iron and free sulphuric acid, probably from the influence of moist air. This change is more rapid than the former, but is less frequently seen in this species, being more com- mon in the following or marcasite. Pyrite is one of the most common minerals in rocks of all ages and classes. The following are a few localities remarkable for fine va- rieties : Elba, pentagonal dodecahedrons three or four inches in dia- meter ; Cornwall, cubes of gigantic dimensions, and other forms ; Persberg in Sweden, large, very perfect octahedrons ; Traversella in Piedmont, well defined, brilliant crystals. Peru, Freiberg, Schemnitz, Dillenbnrg, Kongsberg, Arcndal, Fahlun, Beresow, Alston Moor, and Derbyshire, also famish interesting specimens. Fine varieties Family.'} MARCASITE. 451 occur in the clay at Gross-almerode in Hessia, in the Kenper marls near Rinteln on the Weser, in the chalk at Lewis and Dover, and in the lava of Vesuvius. The auriferous pyrites or Goldkies is found abundantly at Beresow in Siberia, at Marmato in Popayan, in seve- ral places in Mexico, at Aedelfors in Sweden, and in small amount in some parts of the Scottish Highlands. It was formerly used as an ornamental stone ; and in some countries for the manufacture of sulphur, sulphuric acid, and alum. It Is con- sidered injurious when mixed with iron ores, or with the coal used in their reduction, rendering the metal brittle. 401. MARCASITE, Haidinger ; White Iron Pyrites, Phillips ; Strahlkies, Kamkies, Leberkies, Werner ; Wasserkies, Haus- mann ; Fer sulfure blanc, Hauy; Prismatic Iron Pyrites, Mohs. Rhombic; ooP 106 36', ^Poo 136 40', Poo 98 13', Poo 64 30'. The combinations are very various, and besides the above forms show also P and OP. The crystals like fig. 197 p. 359, and fig. 165, p. 295, appear either tabular, or thin prismatic, or pyramidal. Macles are frequent, sometimes united by a face of ooP, at others by a face of Poo . It also forms cockscomb-like groups or spherical, botryoidal, reniform, and stalactitic aggregates, with a radiated columnar, fibrous, or compact texture. It is common in pseudomorphs, or massive and disseminated. Cleavage, prismatic along ooP indistinct, along Poo traces. Fracture uneven. Brittle ; H. = 6 6-5 ; G. = 4- 65 4'9. Colour pale, or greyish bronze-yellow, sometimes almost greenish- grey. Streak dark greenish -grey, or brownish-black. B.B. and with acids acts like pyrite. Chem. com. also identical. Hatchett found 46'4 iron and 53'6 sulphur in one, and 45*66 iron with 54'34 sulphur in another variety. Berzelius, 45'07 iron, 53 % 35 sulphur, 0-70 manganese, and 0'80 silica (= 99'92). This mineral is still more liable to decomposition than pyrite, though in the same manner, and most frequently changes to sulphate of iron. In both minerals this has been ascribed to a mixture of FC' ; but the above analyses all show a surplus of sulphur, which, though small, would rather indicate a mixture of free sulphur as the cause. It, however, has been observed in pure sulphuret of iron, and seems rather to depend on some peculiarity in the state of aggregation. Marcasite agrees in its mode of formation and occurrence with pyrite, though rather less abundant and in smaller masses, and more common in veins than in beds. The following varieties are occa- sionally distinguished. Radiated pyrites or Strahlkies, in radiated masses of various external forms, common in the Harz, Tyrol, Der- 452 PYRRHOTINE. byshire, and other places ; Spear pyrites or Speerkies, a variety of made found very fine at Littmitz, Altsattel, Teplitz, and Przibram in Bohemia, Schemnitz in Hungary, and Freiberg in Saxony ; Hepatic pyrites, or Leberkies, named from its liver-brown colour, is generally a pseudomorphous or decomposing variety, common in the Harz, Saxony, Sweden, Derbyshire, and Cornwall ; Cockscomb pyrites or Kammkies, compound, comb-like crystals, often of greenish colour, or with a brown tarnish, very common in Derbyshire, with galena and fluor-spar ; also at Zellerfeld and Andreasberg in the Harz. Breithaupt and Glocker distinguish a species under the names of Weicheisenkies B. or Wasserkies G., which resembles hepatic pyrites, but contains water in chemical union. Its H. = 3 4 ; and G- = 3.33 3 -50. It occurs in various parts of Moravia and Upper Silesia. Breithaupt's Kyrosite from the Briccius mine near Annaberg is only a variety with part of the iron replaced by copper, and of the sulphur by arsenic, as in Scheidhauer's analysis, 45'60 iron, 53'05 sulphur, 1-41 copper, and O93 arsenic (= 100 99). A variety of the Weiss- hupfererz of Werner from Chili contains, according to Plattner, 12'9 per cent, copper, along with iron and sulphur, but no arsenic. It occurs massive, of a whitish bronze-yellow colour, and may be ranged here, at least till better known. 402. PYRRHOTINE, Breithaupt; Magnetic Iron Pyrites, Phillips; Magnetkies, Werner; Fer sulphure magnetique, Hauy ; Rhoui- bohedral Iron Pyrites, Mohs. Hexagonal ; P 127. The crystals usually of OP . ooP, or this with P (fig. 241) are tabular or short prismatic, but rare. It commonly occurs massive and disseminated, in lamellar, granular, or compact Fig. 241. aggregates. Cleavage, basal perfect, prismatic along ocP imperfect ; brittle. H. = 3*5 4'5 ; G. =4-4 4*7. Colour between bronze-yellow and copper-red, with a pinchbeck-brown tarnish ; streak greyish-black ; more or less magnetic. It remains unaltered in the closed tube, but in the open tube yields sul- phurous fumes, but no sublimation. B.B. on charcoal in the reducing flame fuses to a black strongly-magnetic globule. Soluble in hydro- chloric acid, evolving sulphuretted hydrogen, and depositing sulphur. Analyses, next page. The composition of this mineral is still rather uncertain. It was generally considered to be F 'e, with 63*65 iron and 36'35 sulphur, corresponding nearly to Hatchett's analysis. Stromeyer's experi- ments, however, gave a different result. G. Rose has shown, that Family ] LEUCOPYRITE. 453 Iron. Sul- phur. Nickl. Cop- per. Total. 1 63-5 36'5 100 Hatchett, Cornwall. 2 3 59-85 56-37 40-15 43-63 ... 100 Hill Stromeyer, Treseburg, Harz. Do. Bareges. 4 60-52 38-78 ...a 100-12 H. Rose, Bodenmais. 5 59-64 40-43 ... 100-07 Plattner, Conghonas, Brazil. i 5.9-72 40-22 . 99-94 Do. Fahlun. 7 8 60-59 61 39-41 39 100 100 Scliaffgotsch, Bodenmais (m. of 2). Berthier, Sitten in Valais. 9 56-03 40-46 2-80 0-40 99-69 Scheerer, Moclum, Norway. 10 57-64 38-09 305 0-456 100 Berzelius, Klafva, Smaland, G. =4'674. (a) + 0-82 silica ; (6) + 0-09 cobalt, 0'22 manganese ; 0-46 garnet-powder. it always contains an excess of sulphur above the simple sulphuret, which is not a mere mixture ; that it is always magnetic, which is not true of the simple sulphuret ; and that its specific gravity is al- ways lower than that of the sesquisulphuret, which should not be the case if it were merely a lower sulphuret. He, therefore, adopts the formula 5F'e + Fe'"> w ^ tn 60'44 iron and 39 '56 sulphur. Count Scliaffgotsch gives the same formula for JSTos. 2, 5, 6 of the above analyses, but says there are two other compounds differing in hard- ness and specific gravity, and corresponding to certain copper ores. The one is p'e + Fe'"> wit ^ 43'3 sulphur, like JSTo. 3 ; the other 9 p'e + Fe'"> with 38'4 sulphur, like Nos. 4 and 7. Naumann takes the same composition with G. Rose, but states it as Fe 7 S 8 , or 6 p'e + Fe". It occurs chiefly in the igneous and crystalline or older stratified rocks in veins with various ores. The above are some of its chief localities to which may be added Kongsberg in Norwary, Andreas- berg in the Harz, Moel Elion and Llanrwst in Caernarvonshire, Appin in Argyleshire, and the lavas of Vesuvius. It is also found in some meteoric stones in which, it is said, but inaccurately, to be not magnetic. 403. LEUCOPYKITE, Dana; Arsenicr.l Pyrites, Phillips; Arseni- kalkies, Karsten ; Lolingite, Haidinger ; Axotomous Arsenic Pyrites, Mohs. Rhombic ; coP 122 26', Poo 51 20', Poo 86 10'. The usual Fig. 242. combination is ocP . Poo (fig. 242). It generally occurs massive or disseminated, with a granular or columnar structure. Cleavage, basal rather perfect brachydomatic along Poo imperfect. Fracture un- even. Brittle. H. = 5 5 5 ; G. = 7'1 7 4 (6'9 - 7-1, Breithaupt). Colour silver-white to steel-grey, with a darker tarnish. Streak greyish black. In the 454 MISPICKEL. \_Pyrites closed tube it gives a sublimation of metallic arsenic. B.B. on char- coal emits a strong smell of arsenic, and fuses to a black magnetic globule, which colours borax glass bottle green. Chem. com. Fe As, with 26 5 iron and 73-5 arsenic, or, according to Scheerer, Fe 4 As 3 = 32'5 iron and 67'5 arsenic, but it always contains sulphur, and sometimes nickel and cobalt. Analyses. Iron. Nickel. Cobalt. Arsenic. Sulphur. Serpen- tine. Total. 1 2 3 4 6 6 32-35 30-24 28-06 1349 27-39 28-14 13-37 5*-ib 65-88 63-14 6599 6041 70-09 70-22 1-77 1-63 1-94 5-20 1-33 1-28 3-55 2-17 100-00 98-56 98 -1 97-57 9881 9064 Karsten, Reichenstein. Meyer, Do. Hoffmann, Do. Do. Schladming. Scheerer, Possum. Do. Do. This mineral occurs in serpentine at Reichenstein in Silesia ; in beds with copper nickel, at Schladming in Styria ; with sparry iron at Loling near Hiittenberg in Carinthia ; and in veins in clay-slate with various ores at Andreasberg in the Harz. The variety (Nos. 5, 6) from Fossum in Norway, with G. = 7*09 (7-223, Brett.), agrees with the first formula, and is considered by Scheerer a distinct species. This mineral is used at Reichenstein for the manufacture of arsenious acid, and a small amount of gold was formerly extracted from it. 404. MISPICKEL; Diprismatic Arsenical Iron, Phillips; Arsenik- kies, Werner; Fer arsenical, Hatty; Prismatic Arsenic-Py- rites, Mohs. Rhombic ; o>P 111 53',iPoo 145 26', Poo 80 8', Poo 59 22'. The most common combinations are coP . |Poo , and this with Poo . The maclcs are of two kinds. The crystals are generally short prismatic or tabular, imbedded singly or attached and combined in druses. It is also found massive, granular, or columnar, and disse- minated. Cleavage, prismatic along ccP rather distinct. Fracture uneven. Brittle. H. = 5*5 6 ; G. = 6 6'2. Colour silver- white or almost steel-grey, with a greyish or yellowish tarnish ; streak black. In the closed tube yields first a red then a brown sub- limate of sulphuret of arsenic, and then metallic arsenic. B-.B. on charcoal fuses to a black magnetic globule, which acts like pyrrhotine, and sometimes shows traces of cobalt, colouring borax glass blue. It is soluble in nitric or nitro-chloric acids, with a residue of sulphur and ar&enious acid. Chein. com. Fe S 2 + Fe As, with 19-9 sulphur, Family.'] COBALTINE. 455 46*6 arsenic, and 33 '5 iron, but some varieties contain silver or gold, in others part of the iron is replaced by cobalt. Analyses. Iron. Arsenic.] Sulphur^ Cobalt. Total. 1 3604 42-88 21 -U8 ... 100 Stromeyer, Freiberg. 2 3.5-62 43-73 2065 100 Karsten, Do. 3 33-98 45-74 19-60 99-32 Thomson, Sweden. 4 34-46 4546 2007 99-99 Plattner (the Plinian). 5 26-54 47-55 17-57 8*31 99-97 Scheerer, Skutterud. 6 26-36 46-76 17-34 9-01 100-47 Do. Do. 7 26-97 46-01 18-06 8-38 99-42 Do. Do. 8 30-91 47-45 17-48 4-75 100-59 Wohler, Do. 9 32-94 41-44 17-84 6-45 a 99-68 Hayes (the Danaite). 10 36-44 55-00 8-34 ... b 99-79 Jordan, Andreasberg. (a) + 1-01 impurities ; (6) + O'Oll silver. Mispickel occurs chiefly in igneous rocks, or the cryst alline and transition strata. It is common in Saxony in veins at Freiberg, in beds at Breitenbrunn and Raschau ; in Bohemia in the tin mines of Joachimsthal, Zinnwald, and Schlackenwald ; in Silesia, Hungary, in the veins of silver ores at Andreasberg, and with copper ores at Rammelsberg in the Harz ; in Sweden at Sala, Nora, and Tunaberg ; in various parts of North America, aiid in Cornwall in Wheal Mawdlin, Unanimity, and other tin mines. The cobalt-mispickel, Nos. 5-8, is chiefly from Skutterud near Modum in Norway. The Danaite, No. 9, from Franconia in New Hampshire, North America, seems the same mineral. The Plinian of Breithaupt, No. 4, with G. = 6 -272 6 "467, agrees in composition, but the crystals are monoclinohedric, so that this compound must be dimorphous. It occurs at St Gotthardt, Ehrenfriedersdorf, and Zinnwald. The Weisserz of Werner were the varieties containing silver, like No. 10, which, however, differs in composition. Mispickel is used as an ore of arsenic, and occasionally of silver. 405. COBALTIXE, Beudanl; Bright white Cobalt, Phillips; Glanz cobalt, Werner ; Cobalt gris, Hauy ; Hexahedral Cobalt Py- rites, Mohs. Tesseral and dodecahedral-semitesseral. The usual forms and com- binations resemble those of pyrite above. The crystals are chiefly imbedded, and it also occurs massive, granular, or disseminated. Cleavage, hexahedral perfect. Brittle. H. = 5*5 ; G. = 6'0 6'1 ( 6 '35 Hammanri). Colour silver- white, inclining to red ; often with a greyish or yellowish tarnish. Streak greyish-black ; lustre brilliant. In the open tube, in a strong heat, yields arsenious acid and sulphurous fumes. B.B. on charcoal fuses with strong smell of arsenic to a grey, weak magnetic globule. After roasting shows reaction for 456 SMALTINE. [Pyrites cobalt with borax. Soluble in warm nitric acid, depositing arsenious acid. Chem. com. Co S 2 + Co As, with 35'5 cobalt partly replaced by iron, 45*2 arsenic, and 19*3 sulphur. Analyses. Co- balt. Iron. Arse- nic. Sul- phur. Total. 1 33-10 3-23 43-46 20-08 99-87 Stromeyer, Skutterud. V 3 2977 30>37 638 575 44-75 44-13 19-10 19-75 100 10D Schnabel, Siegen. Hubert, "Orawitza. 4 32-02 4-56 43-63 19-78 99-99 Patera, Do. Found chiefly in the crystalline slates in beds, especially at Skut- terud in Norway, Tunaberg in Sweden, in large resplendent crystals ; Querbach in Silesia, and St Just in Cornwall. The variety from Ora- witza is mixed mechanically with native bismuth (18'40 per cent, in No, 3), and traces of gold. The mixture had G. = 7*4 7*5. 406. SMALTINE, Beudant; Tin-white Cobalt, Phillips; Grey Co- balt, Allan ; Speiskobalt, Werner ; Cobalt arsenical, Hauy ; Octahedral Cobalt-Pyrites, Mohs. Tesseral ; chiefly the cube and octahedron, more rarely also ooO and 2O2. The most common combination is ooOoo . O ; the faces of the cube being often somewhat convex. The crystals sometimes appear cracked ; and are generally combined in druses. It also occurs reti- culated, reniform, or botryoidal ; or shows accidental' specular faces ; or is massive and disseminated, with a granular, compact, or rarely fine columnar texture. Cleavage, only in traces along ooOco , and O. Fracture uneven. Brittle. H. = 5'5 ; G. = 6*4 7'3. Colour tin-white or steel-grey ; with a dark grey or iridescent tarnish. Streak greyish-black. Lustre seldom very brilliant. Gives out an odour of arsenic when broken. In the open tube yields a crystalline sublimate of arsenious acid ; in the closed tube gives no sublimate of arsenic. B.B. on charcoal fuses easily with a strong smell of arsenic to a white or grey magnetic globule, which, with borax, shows reac- tion for cobalt. Easily decomposed by nitric acid, and the solution when heated becomes red with a residue of arsenious acid. Chem. com. Co As, with 71*8 arsenic and 28*2 cobalt, but part of the latter often replaced by iron or nickel. Analyses. Co- balt. Iron. Nic- kel. Cop- per. ! Bis- muth. Arse- nic. Sul- phur. Total. i 20-31 23-44 13-9.5 3-42 4-95 11-71 179 0-16 1 : 39 o'oi 74-22 69-46 70-37 0-89 0-90 0-66 99-00 98-75 99-88 Stromeyer, Biechelsdorf. Varrentrapp, Tunaberg. Hoffmann, Schneeberg. 4 9 44 18-48 trace 1-00 71-08 trace 100-00 v. Kobell, Do. 5 1 9-88 4-77 Ml 1-30 3'8 77-96 1-02 99-92 Kersten, Do, Family.'] MOBUMITE LINNEITE. 457 Smaltine occurs in veins in granite, in the crystalline, transition, and secondary strata, with ores of silver and cobalt. Its chief loca- lities are Schneeberg, Marienberg, and Annaberg, in Saxony ; Joa- chimsthal in Bohemia ; Kieehelsdorf in Hessia in the Kupferschiefer ; Andreasberg in the Harz ; Allemont in Dauphind ; Tunaberg in Sweden ; Chatham in Connecticut ; Wheal Sparnon, Doalcoath, and Kedruth in Cornwall. The varieties with much iron, named from then' colour grey smaltine, have a higher specific gravity (6 '9 7*3) than the others, (only 6'3 6*6) ; and then- solution in nitric acid gives a precipitate of iron peroxide. In a fibrous variety from Schnee- berg, John found 28 cobalt, 65'75 arsenic, and 6*25 peroxide of iron and manganese, probably mixed. The Wismuthkobaltkies of Ker- sten, from Schneeberg No. 5, containing bismuth ; and the Yellow Smaltine or Kieskobold, from Siegen, with pyrite, are probably mere mixtures. .. Smaltine and cobaltine are used in preparing blue colours for painting porcelain and stoneware, and one grain of the oxide will give a full blue to 240 grains of glass. The arsenic driven oif during the roasting of the ores, is also collected. 407. MODUMITE, N. ; Tesseralkies, Breithaupt ; Hartkobalterz, Hausmann; Skutterudite, Haidinger. Tesseral ; O and ooOoo with ooO and 2O2, or massive and gra- nular. Cleavage, hexahedral distinct. Fracture conchoidal or un- even. Brittle ; H. = 6 ; G. = 6*74 6'84. Colour between tin- white and pale lead-grey, sometimes with an iridescent tarnish. Lus- tre rather brilliant. In the closed tube it gives a sublimate of metallic arsenic ; in the open tube a very large sublimate of arsenious acid. In other respects acts like smaltine. Chem. com. Co 2 As 3 with 79 '2 arsenic and 20'8 cobalt. Analyses. Co- balt. Iron. Ar- senic. Sul- phur. Total. 1 2 3 20-01 18-5 19-5 151 1-3 1-4 77-84 7,0.2 79.0 0-69 100-05 990 99-9 Scheerer. Wohler, crystallized. Do. massive. It occurs in a metaliferous bed in mica-slate at Skutterud, near Modum in Norway. 408. LINNETTE, Haidinger; Sulphurct of Cobalt, Phillips; Kobaltkics, Hausmann ; Isometric Cobalt-Pyrites, Mohs. Tesseral. It occurs in octahedrons and cubes, the former some- times maclcd by a face of O ; also massive and disseminated. Cleav- age, hexahedral imperfect ; brittle. H. = 5*5 ; G. = 4*9 5*0. 458 GRtJNAUITE. [Pyrites Colour silver- white inclining to red, often with a yellowish or copper- red tarnish ; streak blackish-grey. B.B. on charcoal evolves sul- phurous vapours, and fuses in the reducing flame to a grey magnetic globule, bronze-yellow when broken. With fluxes shows reaction for cobalt. Soluble in warm nitric acid, with residue of sulphur. Chem. com. Co S + Co 2 S 3 , with 57'9 cobalt and 42-1 sulphur, but part of the former replaced by iron or copper. Analyses. 1 1 c - |balt. Iron. Cop- per. Sul- phur. Vein- stone. Total. \l 43-20 43-86 3-53 5-31 14-40 4-10 38-50 41-00 0-33 0-67 99-96 94-94 Hisinger, Riddarhytta. Wernekink, Musen. \ 3 ( 53-35 2-30 0-97 42-52 98-87 Do. Do. This mineral has been long known in Sweden, and is noticed by Linneus, hence the name given to it by Haidinger. It is found in a bed in gneiss with copper pyrites and hornblende at Bastnass near Ridderhytta in Sweden ; in veins in transition rocks, with various ores at Mlisen near Siegen ; and in the La Motte mine in Jefferson County in Missouri. Syepoorite. This name may be given to a sulphuret of cobalt, pro- bably a distinct species, found in primary rocks with pyrite and chal- copyrite at Syepoore near Rajpootanah in North West India. It is steel-grey or yellowish, with G. = 5*45,* and contains, according to Middleton, 64-64 cobalt and 35'36 sulphur, or very nearly Co S. The Indian jewellers use it to give a rose colour to gold. 409. GRUNAUITE, N.; Nickel Bismuth, Dana; Nickelwismuthglanz, von Kobett, Mohs. Tesseral, O and ocOco , in veiy small crystals. It also occurs gra- nular and disseminated, Cleavage octahedral ; brittle. H. = 4-5 ; G. = 5*14. Light steel-grey inclining to silver-white, with a yellow or greyish tarnish. B.B. on charcoal fuses to a brittle, magnetic bead, grey externally, and yellow on the fracture, and colours the support yellow ; with borax shows the reaction for nickel. Soluble in nitric acid, with a residue of sulphur ; the solution is green, and gives, when the free acid is removed, a precipitate with water. Von Kobell found 40-65 nickel, 14-11 bismuth, 38-46 sulphur, 3-48 iron, 0'28 cobalt, T68 copper, 1-58 lead (= 100*24), which subtracting the mixtures gives 45-40 nickel, 15'76 bismuth, and 38*84 sulphur (= 100). For this Frankcnheim proposes the formula N'i (NI'" Bi"') (?) It occurs at Griinau in Sayn-Altenkirchen usually mixed with quartz. Family.'] GERSDOFFITE. 459 410. GERSDORFFITK, Lowe, Haidinger ; Nickel Glance, Dana ; Nickelglanz, Pfaff, Hausmann; Nickelarsenkies, Naumann; Eutomous Cobalt Pyrites, Mohs in part. Tesseral; O, ooOx, sometimes-^-. Usually it is massive and granular. Cleavage, hexahedral ratlier perfect. Fracture uneven. Brittle. H. = 5-5 ; G. = 6'0 6-13 ( 6'64 ?). Silver- white in- clining to steel-grey, with a grey or greyish-black tarnish. In the closed tube decrepitates violently, and when strongly heated gives a large sublimate of yellowish- brown sulphuret of arsenic ; the residue is red and acts like copper-nickel. Partially soluble in nitric acid, depositing sulphur and arsenious acid. Analyses. Nick] Arse- nic. Sul- phur. Iron. Cobalt Total. 1 24-42 45-90 12-36 10-4fi ... 93-14 Pfaff, Loos, Sweden. 2 29-94 45-37 19-34 4-11 0*-92a 100-58 Berzelius, Do. 3 276 48 14 11 ... 100 Dobreiner, Camsdorf. 4 5 31-82 38-42 48-02 42-52 20-16 14-22 2-V>9 ...c 100 99-12 Rammelsberg, Lobenstein. Lowe (massive), Schladming.G. =6'7 6-9. 6 2614 49-83 14-13 9-55 9965 Do. (cryst.) Do. (m. of 3) 7 19-59 39-04 i 16-35 11-13 14-12 100-23 Pless, Do. Do. G. =6-64. 8 27-90 3988 1G-11 14-97 0-83 99-69 Do. Do. Do. Do. 9 28-62 39-40 16-91 12-19 2'88 100 Do. Do. Do. Do. 10 30-30 44-01 18-83 6-00 ...d 100 Rammelsberg, Harzgerode, G.= 5'61 5-65. 11 12 28-75 37-34 46-10 45-34 16-25 14-00 8-90 2-50 trace e 100 100 Lowe, Prakendorf, Hungary, v. Kobell (Amoibit). (a) With copper + 0-90 silica; (b) with cobalt; (c) + 1.87 quartz; (d) + 0-86 antimony ; ,) + 0-82 lead. These analyses seem to admit of no common formula. Nos: 2, 4, 10 may be generally represented by (Ni Fe) (S 2 , As), or Ni As + Ni S 2 , with 35'5 nickel, 45'2 arsenic, and 19'3 sulphur, part of the nickel being replaced by iron or cobalt. No. 5, a massive variety, was probably impure, as No. 6 in crystals agrees tolerably with the gene- ral formula. Nos. 7, 8, 9, also from the same locality, are remarkable for containing cobalt, which has not been observed in this variety, either by Lowe or Kammelsberg. Including it with the iron and a part of the nickel, as R, the nearest formula would be Ni As + 2RS = 45*1 R or nickel, 38*5 arsenic, and 16'4 sulphur ; but the variable amount of cobalt seems improbable in a crystallized mineral Gers- dorffite is used as an ore of nickel, and occurs near Harzgerode and Tanne in the Harz ; Schladming in Styria, Camsdorf near Lobenstein in Thuringia, Loos in Helsingland, Sweden ; also in Spain and Brazil. The Amoibite of v. Kobell (No. 12 analysis) from Lichtenberg in the Fichtelgebirge, occurs in small octahedrons with a similar cleav- age. Its colour is light steel-grey. H. = 4 ; G. = 6-08 or more. In 460 ULLMANNITE. [Pyrites chemical action it resembles gersdorffite, but the analysis is nearer Ni 2 (As 3 , S 3 ). Tombazite, Breithaupt, from near Lobenstein, contains, according to Plattner, nickel, arsenic, and a little sulphur, with traces of cobalt and iron. It is bronze-yellow or pinchbeck-brown. H. = 4 5 ; G. = 6'637, and occurs in cubes with a hexahedral cleavage. Its true nature is still uncertain. The Wodankies, in which Lampadius supposed he had found a new metal, Wodan, from Topschau in Hungary, probably belongs to the gersdorffite. Wackenroder describes a nickel-glance from Oelsnitz in the Voightlande as a new species, but the specimen analyzed was so impure as to admit of no certain result being deduced. 411. ULLMANNITE, Frobel, Haidinger; Antimonial Nickel, Phillips; Nickel- Stibine, 7J>aw ; Antimonnickelglanz, Hausmann ; En- tomous cobalt pyrites, Mohs in part. Tesseral ; O, ooOoo , O. It also occurs massive and fine gra- nular or compact ; sometimes in columnar portions bounded by crystal-faces. Cleavage, mere ' traces ; fracture uneven ; brittle. H. = 5-5; G. = 6-4 7-2. Tin- white, but assumes first a grey, then a blackish tarnish, and loses its lustre. Sometimes covered by a green efflorescence of arseniate of nickel. Yields an odour of ar- senic even when broken. In the closed tube forms a sublimate of metallic arsenic, and becomes copper-red. In the open tube yields arsenic and arsenious acid. B.B. on charcoal fuses easily with much smoke, continues long ignited, and becomes invested with crystals of Family.'] MILLERITE. 463 arsenious acid. At length leaves a brittle grain of metal, with green spots. Chem. com. M As, with 28'2 nickel and 71 "8 arsenic. Ana- lyses. Nickl. Co- balt. Iron. Bis- muth. Cop- per. Arse- nic. Sul- phur. Total. 1 28-14 2 2074 3 28-40 4 29-50 3*37 ... 3-25 trace trace 2-19 0-50 71-30 72-64 70-34 70-93 0-14 102-27 1 -00 74 100-43 Hoffmann. Schneeberg. Booth, Riechelsdorf. Kainmelsberg, Camsdorf, G. 6735. Do. Do. Breithaupt has recently divided this mineral into two species. The one is rhombic, in oblique prisms of 123 124, and G. = 7-099 7-188. Colour tin-white, inclining to red on the fresh frac- ture. It occurs at Schneeberg and Riechelsdorf, and is the variety analyzed by Hoffmann (No. 1). The other species is tesseral, as described above, and has G. = 6'432 6-565. It occurs in the same places, and is the variety analyzed by Booth (No. 2), perhaps also by Rammelsberg, from Camsdorf near Saalfeld. This compound is therefore dimorphous. Breithaupt names the former Weissnickelkies, and the latter Chloanthite ; but it would be better to apply the latter term to the rhombic species, and retain Haidinger's name for the other. 416. MILLERITE, Haidinger ; Sulphuret of nickel, Phillips ; Haar- kies, Werner, Mohs ; Capillary Pyrites, Dana; Mckelkies, Hausmann ; Nickel natif, Hauy. Rhombohedric, in very fine acicular and capillary crystals, which, according to Miller, are hexagonal prisms with rhombohedric termi- nations, oo P2 . R. Cleavage unknown. Brittle. H. = 3*5; G. = 5*26 5*28 (Miller}. Colour brass or bronze-yellow, with a grey or iridescent tarnish. In the open tube yields sulphurous acid. B.B. on charcoal fuses easily to a blackish metallic globule, which boils and sputters, and acts with borax like nickel oxide. In nitro-chloric acid forms a green solution. Chem. com. M S, with 64-76 nickel and 35 -24 sulphur. Analyses. y Nickel. Iron. Copper. Sul- phur. Total. 64-35 61-34 173 l"l4 34-26 35-79 98-61 100-00 Arfvedson. Ramraelsberg, Camsdorf, G. 6'65. This mineral is rather rare, but it is found in veins in the second- ary and crystalline rocks at Johann-Georgenstadt in Saxony ; Jo- 464 EISENNICKELKIES CHALCOPYRITK. [Pyrites achimsthal and Przibram in Bohemia ; Camsdorfin Thuringia; Riech- elsdorf in Hessia ; in the Westerwald ; near St Austle in Cornwall, and at Merthyr Tydvil. 417. EISENNICKELKIES, Schtcrcr. Tesseral. It occurs massive and granular, with an octahedral cleavage. Fracture uneven ; brittle. H. = 3'5 4 ; Gr. = 4-6. Light pinchbeck brown, with darker streak. Not magnetic. B.B. acts in general like pyrrhotine. The roasted powder forms with bo- rax in the oxidating flame a glass coloured by iron ; in the reducing flame a black opaque glass. Chem. com. 2 Fe S + Ni S, with 36 sulphur, 42 iron, and 22 nickel ; or, by Sheerer's analysis, 40 -21 iron, 21 '07 nickel, 1-78 copper, and 36 -64 sulphur (= 99-70). It occurs along with copper pyrites in a greenish-black hornblende near Lille- hammer in Southern Norway. 418. CHALCOPYRITE, J3ewcfcm; Yellow Copper ore, Copper Pyrites, Phillips; Kupferkies, Werner ; Cuivre pyriteux, Hauy ; Pyra- midal Copper Pyrites, Mohs. Tetragonal and sphenoidal-hemihedric. The fundamental form P often appears as the sphenoid | with the horizontal polar edges = 71 20' ; and still more frequently as ^ . J (P and /") O ther common forms are Poo (&), 2Poo (c) 126 11', OP (a), ooP, ooPoo , and many scalenohedrons. The crystals, generally small and deformed by the shortening or elongation of one side, are attached singly or in druses, fig. 244 being a very characteristic form. Macles are very common, according to various laws, as like fig. 245 ; and when repeat- Fig. 244. Fig. 245. ed several times, obscure still more the forms of the single crystals. Most commonly it is found compact and disseminated, sometimes also Family.'] CHALCOPYRITE. 465 botryoidal and reniform. Cleavage, pyramidal along 2Poo sometimes rather distinct. Fracture conchoidal or uneven. H. = 3 '5 4 ; G. = 4'1 4*3. Colour brass-yellow, often with a gold-yellow or iridescent tarnish ; streak greenish-black. B.B. on charcoal becomes darker or black, and on cooling red. Fuses easily to a steel-grey globule, which at length becomes magnetic, brittle, and greyish-red on the fractured surface. With borax and soda yields a grain of copper. In the open tube it evolves sulphurous acid, but no subli- mate. Moistened with hydrochloric acid, it colours the flame blue. Soluble in nitrochloric acid, leaving sulphur, with more difficulty in nitric acid. Chem. com. essentially 1 atom copper, 1 atom iron, and 2 atoms sulphur, and hence either c'u p'e, or more probably c'u PO'", with 34'5 copper, 30'5 iron, and 35 sulphur. Analyses. 1 2 3 4 5 6 7 8 Cop- per. Iron. Sul- phur. Quartz. Total. 34-40 33-12 30-00 31-20 33-3 32-1 31-2 22-96 30-47 30-00 32-20 30-80 30-0 31-5 322 42-51 35-87 36-52 35-16 34-46 32-0 36-3 33-6 34-75 0-27 0-39 2-64 l-10a :."<; 1 : 6 ... b 101-01 100-03 100 100 97-9 99-9 98-6 100-75 H. Rose, Kammelsberg, Sayn. : Do. Furstenberg. Phillips, Cornwall, crystallized. Do. Do. botryoidal. Berthier, Saxony, massive. Do. Allevard, Dept. Isere, Do. Do. Scheidhauer (the Cuban). (a) + 2 44 lead, arsenic, and loss; (b) trace of lead. This is the most abundant of the ores of copper, and occurs in many localities and geognostic situations. It is the most common ore in the Cornish mines ; and the varieties from Gunnis Lake and St Austle are remarkable for their splendid tarnish colours (peacock copper ores). In Scotland it occurs at many points on the shore of Kirkcud- bright and Wigtonshires, at Tyndrum in Perthshire, in Inverness- shire, Zetland, and other places. Of foreign European localities, Fahlun, Roraas, Freiberg, Mansfeld, Goslar, Lauterberg, Musen, may be mentioned. It is common in Siberia, less abundant in the United States, and has recently been discovered in immense profusion in vari- ous parts of Australia. In 1847 there was raised in Cornwall and Devon 155,985 tons of copper ore, producing 12,754 tons of copper, worth L.889,287. This gives 8 per cent, metal on the average ; and the ore picked for sale at Redruth rarely yields 12, sometimes only 3 or 4 per cent. In 1847 there was also sold at Swansea 746 tons of copper ore from other British mines, 14,373 tons from Irish mines, and 50,819 tons from foreign mines. In 1846 about 1700 tons of copper were exported from Russia. " The richness of the ore," says Allan, " may in general be judged of by the colour ; if of a fine yellow hue, and yielding readily to the hammer, it may be considered a good ore ; but if hard and pale- yellow, it is assuredly a poor one 7 being mixed with iron pyrites. 466 BORNITE. {Pyrites The crystallized varieties are always rich. Though its colour is somewhat brighter than that of iron pyrites, the two may frequently be confounded ; it yields, however, to the knife, which iron pyrites does not, and is decidedly softer than that mineral. Iron pyrites, more- over, most commonly occurs crystallized, copper pyrites rarely so. Iron pyrites is subject to decomposition, copper pyrites only to tar- nish. Iron pyrites does not afford a green solution in nitric acid, while copper pyrites does so in a few minutes. From gold it is readily distinguished by its fracture and tenacity it being brittle, whereas gold is malleable." This mineral is often mixed with iron pyrites, and occasionally contains a small proportion of silver or gold. The Cuban of Breithaupt, only found massive, but with a hexahe- dral cleavage from Bacaranao in Cuba, has G. = 4*026 4*042, and agrees in general characters with chalcopyrite, but is more easily fusible. The analysis, No. 9 above, corresponds to one atom pyr- rhotine (33-64) and two atoms chalcopyrite (66 '61) ; and it is either a compound or mere mixture of these minerals. 419. BORNITE, Ilaidinger ; Purple copper, Phillips ; Buntkupfererz, Werner, Allan ; Variegated copper, Jameson ; Octahedral Copper Pyrites, Mohs. Tesseral ; ooOoo , and ooOoo . O occur, and also macles united by a face of O ; but crystals are rare and generally with rough uneven faces. It is mostly found massive and disseminated. Cleavage, oc- tahedral, but very imperfect. Fracture conchoidal or uneven. Slightly brittle, or almost sectile ; H. = 3 ; G. = 4-9 5-1. Colour be- tween copper-red and pinchbeck-brown, with very pale tarnish, espe- cially steel-blue, inclining to red and green. Streak greyish -black. B.B. acts like chalcopyrite. Soluble in concentrated hydrochloric acid, leaving sulphur. Chem. com. of the crystallized varieties es- sentially 3 atoms copper, 1 atom iron, and 3 atoms sulphur, or c ' u 3 Pe '", with 55'6 copper, 16*4 iron, and 28 sulphur, but often, especially in the compact varieties, mixed with chalcophyllite or copper glance. Analyses. Cop- per. Iron. Sul- phur. Quartz, &c. Total. J 2 61-07 7i-oo 14-00 6-41 2375 22-58 0-50 99-32 99-99 Phillips, Ross Island, Killarney. Plattner, Sangershausen. 3 6973 7-54 22-65 9992 Do. Eisleben. 4 63-03 11-56 25-06 ... 99-65 Do. Woitzkisch, White Sea. 5 56-76 14-84 28-24 99-84 Do. Condurra mine, Cornwall. 6 56-10 1736 25-80 0-i*2 99-38 Do. Dalarne, Sweden. 1 3 58-20 63-33 14-85 11-80 26-98 24-70 ... 100-03 9983 Varrentrapp, crystallized. Hisinger, Vestanforss. 9 62-75 11-64 25-70 0-04 100-13 Bodemann, Bristol, Connecticut. 10 5789 14-94 26-84 0-04 9971 | Chodnew, Redruth., crystals. Family.'] DOMEYKITE. 467 Crystals of this mineral have only been procured in Cornwall, par- ticularly at Tincroft and Dolcoath near Kedruth. It occurs massive in rocks of various age in Norway, Sweden, Greenland, Silesia, Mansfeld (in the kupferscMefer), the Bannat, Tuscany, Siberia, and North America. It is used as an ore of copper. 420. DOMEYKITE, Haidinger ; Arsenkupfer, Zincken ; Arseniure de Cuivre, Domeyko. Occurs botryoidal, reniform, or in thin veins, also massive and dis- seminated. Fracture uneven or conchoidal. Brittle ; H. = 3 3*5. Colour tin or silver-white, inclining to yellow, or with an iridescent tarnish. Unchanged by ignition in a close vessel. B.B. fuses easily with strong 1 odour of arsenic. Not aifected -by hydrochloric acid. Chem. com. Cu 6 As, with 71-63 copper and 28*37 arsenic. Analyses. Cop- per. Iron. Ar- senic. Sul- phur. Cop- per prot. Arse- nious acid. Watr. Total. 1 71-65 28-36 ... 10001 Domeyko. 2 7070 0-52 2329 387 98-38 Do. 3 ... 1-51 3-06 60-50 25-94 8-99 100 Faraday. 4 12-81 5 ... 3 : 476 13-89 2-20 62-29 79'OOa 3-70 8-03 5-83 9-50 100-72 100 Rammelsberg. v. Kobell. 6 6021 0-25 19-51 2-33 ...c 2-41 100 Blyth. (a) Sub-oxide; (6) peroxide; (c) + 15-29 organic matter = 1-62 carbon, 0'44 hydrogen, 0-06 nitrogen, and 13-17 oxygen. No. 1 is the pure mineral from Calabazo in Coquimbo ; No. 2 from the Antonio mine in Copiapo in Chili is mixed with chalcopyrita Nos. 3-6 are the Condurrite of Faraday, found in the Condurrow mine near Helstone, and more recently in the Wheal Druid at Cam Brae near Redruth, Cornwall. It is massive, soft, and soils the fingers, fracture flat conchoidal, colour brownish or bluish-black : G. = 4-20 4-29. In tht3 closed tube it yields water and arsenious acid. B.B. on charcoal fuses with escape of arsenic vapours to a globule, which, on cooling, cracks, swells and falls to pieces. Treated with soda and borax, it leaves a grain of copper. In No. 4 the mineral was decomposed by hydrochloric acid, the metallic copper, arsenic, and sulphur, = 28'90, being imdissolved. According to Rammels- berg, it is a mixture of red copper ore, arsenious acid, glance copper, and arsenic- copper, and is probably formed from the latter. No. 5 is an analysis of the portion soluble in hydrochloric acid by v. Kobell, who considers the remainder as finely-divided arsenic and a little sul- phuret of copper. Dr Blyth has since examined this mineral, No. 6 being the composition of the mineral as a whole. He considers, from a mean of many analyses, that the original arsenid contained 71 '15 copper, and 28'84 arsenic, and is consequently identical with the Domeykite, which may probably occur in the same mines. 468 ARSENIURET OF MANGANESE GALENA. [Lead Glance 421. ARSENIURET OF MANGANESE, Kane. Massive and botryoidal, with a granular or foliated structure. Fracture uneven; brittle; G. = 5 -55. Colour greyish-white, with a black tarnish. B.B. burns with a blue flame, and emits fumes of arsenic. Soluble in nitro- chloric acid. Chem. com. Mn As, accord- ing to Kane, who found 45*5 manganese, 51*8 arsenic, and trace of iron (= 97'3). It occurred on a mass of galena said to be from Saxony, but is very imperfectly known. II. FAMILY. LEAD GLANCE. 422. GALENA ; Sulphuret of Lead, Phillips ; Bleiglanz, Werner ; Plomb sulfure, Hauy ; Hexahedral Lead-glance, Mohs. Tesseral ; usual forms coOoo , O, ooO ; seldom 2O, or other tria- Msoctahedrons, and 2O2, or other ikositetrahedrons. The most com- mon combination is ccOoo . O ; the crystals, of various sizes, are seldom perfectly formed, and occur rarely imbedded, mostly attached or in druses. The macles are conjoined by a face of the octahedron. It also forms metasomatic pseudoniorphs after pyromorphite, or ap- pears reticulated, cellular, corroded, tubular, botryoidal, or encrust- ing. It occurs most frequently massive and disseminated in granu- lar, compact, or striated laminar aggregates. Cleavage, hexahedral very perfect, and hence the fracture is scarcely observable. Sectile. H. = 2-5; G. = 7-4 7-6. Colour lead- grey.; when tarnished be- comes darker, or rarely iridescent. Streak greyish- black. In the open tube it yields sulphur and a sublimate of sulphate of lead. B.B. on charcoal decrepitates, gives off sulphur, fuses, and leaves a glo- bule of lead. Soluble in nitric acid, with evolution of nitrous acid and residue of sulphur. Nitro-chloric acid changes it into sulphate and chloride of lead. Chem. com. essentially p'b, with 86'7 lead and 13 -3 sulphur. Analyses. Lead. Sul- phur. Silver. Iron. Zinc. Total. 1 2 3 4 5 (> 83-0 85-13 79-60 84-fi3 8180 83-61 16-41 13-02 13-40 13-21 14-41 14-18 0-08 7-0*0 : ) 359 218 99-49 98-G5 100 97-84 SW-80 99-97 Westrumb, Lauenstein, Hannover. Thomson, Durham. Beudanf, Schcmnitz. Robertson, Inverkeithing, Scotland. Lerch. Przibram (G. = /-252>. Do. " Do. (G, = 7-324). Galena usually contains a small proportion of silver, in general from O'Ol to 0-03, or even 0-05 per cent. ; very rarely 1 per cent. Family.'] CUPROPLUMBITE. 469 or more. The pure galena ores in the Harz, with 60 71 per cent, lead, contain only O03 to O05 silver ; the English lead ores only 0'02 to O03 per cent. ; and those of the Leadhills in Scotland from 0'03 to 0'06 per cent. Some galena contains selenium, as, according to Berzelius, that from Fahlun and Atwidaberg, and yields its peculiar smell when roasted on charcoal. Antimony and copper also oc- cur in galena ; and, in a variety from the Charente department in France, platina is said to have been found. The varieties Nos. 5 and 6 were parallel groups of very small cubical crystals, distinguish- ed by their low specific gravity and the zinc, which in 5 is as 1 z'n to 8 p'b, in 6 as 1 to 12. The super sulphur et of lead from Dufton, with 90-38 sulphuret of lead and 8'71 sulphur (Johnston), and another from Ireland, with 98'21 sulphuret of lead and T79 sulphur (Thom- son), are probably galena mixed with sulphur. The former burns even on exposure to the flanate of a candle. Galena is a very common mineral in rocks of all ages and forma- tions. It is found in veins in gneiss at Freiberg ; in mica-slate at Tyndrum in Perthshire ; in transition or Silurian clay-slate and greywacke in the Harz, the Rhenish provinces, Styria, Wales, the Leadhills and other places in Scotland ; in the Killas of Cornwall ; in the carboniferous limestone of Derbyshire, Cumberland, and many parts of Scotland ; in Wurtemberg in veins in the bunter Sandstein and Muschelkalk ; in Carinthia, Galicia, and other parts of Austria in the Alpine limestone ; in the Eifel disseminated through sandstone ; at Linares in the Sierra Morena in veins in granite ; in the Pentland hills in Scotland in claystone porphyry. In Missouri, Wisconsin, and the Western States of Xorth America it occurs in immense abun- dance in the cliff limestone. Large crystals have been obtained at Dufton and Alston Moor in England ; at Leadhills, Inverkeithing, and in Islay in Scotland ; and the specular or slickenside variety at Castletou in Derbyshire and Allouhead in Durham. It forms the chief ore of lead in this country. In 1847 the produce of the United Kingdom was 83,747 tons ore, yielding 68 percent, or 55,703 tons lead. Of the latter, England furnished 39,507 tons, Wales 12,294 tons, Ireland 1380 tons, Scotland 822 tons, and the Isle of Man 1699 tons. 423- CUPROPLUMBITE, Breithaupt. Tesseral ; but only found massive with a distinct hexahedral cleav- age. Rather sectile and brittle. H. = 2 -5; CT. = 6-408 6 ; 428. Colour blackish lead-grey ; streak black. In the open tube fuses with effervescence, and emits sulphurous acid. B.B. on charcoal does not decrepitate, but covers the support with protoxide of lead and sul- phate of lead. With soda gives a grain of metal. Chem. com. 470 CLAUSTHALITE SELENCOPPERLEAD. [Lead Glance c'u Pb' 2 OT i y Plattner's analysis, 64-9 lead, 19-5 copper, 0-5 silver, and 15-1 sulphur (=100). It is found in Chili, and mostly exported to England. 424. CLAUSTHALITE, Beudant ; Selen-lead, Selenblei, H. Rose, Mohs ; Seleniuret of Lead, Phillips. Tesseral ; but found massive and disseminated in small or fine granular aggregates, with a hexahedral cleavage. H. = 2-5 3 ; G. = 8*2 8'8. Colour lead-grey ; streak grey. In the closed tube often decrepitates violently, in the open tube yields a grey or red sublimate of selenium. B.B. on charcoal fumes, smells of selenium, colours the flame blue, stains the support red, yellow, and white, and volatilizes, except a small remainder, without fusing. Soluble in nitric acid, leaving selenium. Chem. com. Pb Se, with 72*7 lead (partly replaced by silver) and 27*3 selenium. 'Analyses. Lead. Co- balt. Iron. Silver. Mer- cury. Sele- nium. Total. 1 71-81 ... 27-59 99-40 H. Rose, Tilkerode. 2 3 70-98 63-92 0-83 3-14 045 ... ... 28-11 31-42 99-92 98-93 Stromeyer, Clausthal. H. Rose, Tilkerode. 4 5 60-15 55-84 ... li-67 16-94 26-52 24-97 98-34 97-75 Rammelsberg, Do. H. Rose, Do. 6 27-33 ... ... ... 44-69 27-98 100 Do. Do. Clausthalite occurs near greenstone (diabase) in the transition rocks of the Harz, usually with brown spar, as at Lerbach, Zorge and Tilkerode (rarely with gold and palladium). Also in a vein of brown spar at Reinsberg near Freiberg in Saxony. No. 3 is the Selencobalt- lead of the Germans, G. = 7'697, and known by colouring borax glass smalt-blue. It occurs near Clausthal in the Harz, and gives Co Se 2 + 6 Pb Se. No. 4 is a selenid of silver and lead, but part of the selenium lost ; it was examined for sulphur by R., but without success. Nos. 5 and 6, the Selenquechsilberbki of the Germans, the Selenid of Mercury and Lead of Dana, found at Lerbach and Tilke- rode, seems a mere mixture of Selen-lcad and Selen -mercury. In the closed tube it gives a sublimate of the latter, and with soda, mer- cury. 425. SELENCOPPERLEAD ; Selenkupferblei and Selenbleikupfer, H. Rose, Mohs, *c. ; Seleniuret of lead and copper, Phillips. Massive and disseminated, with a small or fine granular texture. Sectile. H. = 2*5 ; G. = 7 7-5. Colour light lead-grey inclin- ing to brass-yellow, or with a bluish tarnish. Streak darker. B.B. acts like clausthalite, only some fuse slightly on the surface, others (No. Family.'} ONOFRITE NAUMANNITE. 471 1) easily forming a grey metallic mass. The residue shows reaction for copper. Chem. com., either Cu Se with 1, 2, or 4 atoms of Pb Se ; or, more probably, as Frankenheim observes, indeterminate com- binations of Cu 2 Se, and Ptt Se, considered as isomorphous. Ana- lyses. Lead. Cop- per. Silver. Iron. Iron perox. Sele- nium. Quartz. Total. 1 47-43 15-45 1-29 2-08a 34-26 ... 100-51 H. Rose, Tilkerode. 2 59-67 7-86 0-33& 29-96 1.00C 99-26 Do. Do. 3 4 53-74 63-82 8-02 4-00 0-05 0-07 ...d traced 2-00 30-00 2935 4-50 2-06 98-31 99-30 Kersten, Glasbachgrunde. Do. Do. (a) With lead; (6) +0-44 iron and lead; (c) undecom posed mineral; (d) + traces of sulphur. This mineral occurs with clausthalite at Tilkerode and Zorge in the Harz ; at Glasbachgrunde near Gabel in Thuringia, in a vein in clay- slate ; and also, it is said, at Eeinsberg near Freiberg. 426. ONOFRITE, Haidinger. Massive, and granular. H. = 2 '5. Colour blackish lead-grey or steel-grey. Streak shining. In the closed tube wholly volatile with a black sublimate. With soda gives metallic mercury. Chem. com. Hg Se -f- 4 Hg S, corresponding to H. Rose's analysis, which gare 81-33 mercury, 6'49 selenium, and 10-30 sulphur (= 98-12). It oc- curs at St Onofre in Mexico with mercury in veins. A similar mine- ral seems to occur at Zorge in the Harz. Del Rio mentions other compounds of selenium and mercury as occurring at Culebras in Mex- ico, and one containing zinc (24 per cent.), but they are very imper- fectly known. Zincken notices two minerals containing selenium, copper, and mercury, from Tilkerode, also little known. 427. NAUMANNITE, Haidinger ; Seleniuret of Silver, Phillips ; Selensilber, G. Rose^ Mohs. Massive, and in thin plates with a granular texture. Cleavage, hexahedral perfect. Malleable. H. = 2-5 ; G. = 8. Colour and streak iron-black ; lustre splendent. In the closed tube fuses with a slight sublimate of selenium and selenic acid. B.B. on charcoal in the oxidating flame fuses quietly, in the reducing flame boils, and when cooling ignites. With soda and borax gives a grain of silver. Easily soluble in concentrated nitric acid. Chem. com. Ag Se, with 73 sil- ver and 27 selenium. G. Rose found 65'56 silver, 4-9 1 lead, and 29*53 selenium (=100). It occurs at Tilkerode in the Harz with clausthalite, and in small 472 ARGENTITE. [Lead Glance veins in greenstone. Del Rio mentions a double-selensilver as found at Tasco in Mexico. It is lead-grey, malleable, and crystallizes in six-sided tables. The Silverphyttinglanz of Breithaupt, from gneiss at Deutsch-Pilsen in Hungary, is, according to Plattner, a mixture of selensilver and selenmolbdena, with a little gold. It occurs massive, in foliated ag- gregates, with a perfect cleavage in one direction, the thin lamina flexible. H. = 1 2 ; G. = 5'8 5'9. Colour dark drey. 428. ARGENTITE, Haidinger ; Sulphuret of Silver, Phillips ; Gla- serz, Werner ; Silberglanz, v. Leonhard ; Argent sulfure, Hauy ; Hexahedral Silver Glance, M ohs. Tesseral ; usual forms ooOoo, O, ooO, and 2O2 (fig. 246). The Fig. 246. crystals are generally misshapen, with un- even or curved faces ; the icositetrahedrons sometimes so drawn out as to appear like eight-sided pyramids. The crystals occur attached singly, but most commonly in druses, or in linear and stair-like groups ; also arbo- rescent, capillary, filiform, or reticulated. It also appears in crusts, or massive and disse- minated. Cleavage, in veiy indistinct traces along ooO and ooOoo . Fracture uneven and hackly ; malleable and flexible. H. = 2 2-5 ; G. = 7 7-4. Lustre rarely brilliant, stronger on the streak. Colour blackish lead-grey, often with a black, brown, or rarely iridescent tarnish. B.B. on charcoal fuses, intumesces greatly with sulphurous fumes, and finally leaves a grain of silver. Soluble, with residue of sulphur, in concentrated nitric acid. Chem. com. Ag, with 87 silver and 13 sulphur. Klaproth found 85 silver and 15 sulphur (or, according to Beudant's calcula- tion, 86*5 silver and 13-5 sulphur), in a variety from the Himmelsfurst mine near Freiberg, and 86'39 silver with 13-61 sulphur, in another from Joachimsthal in Bohemia. Occurs chiefly in gneiss, in mica, hornblende and clay-slates, in gra- nite, porphyry, and trachyte. It is found abundantly in Saxony, at Freiberg, Marienberg, Annaberg, Schneeberg, Johann-Georgenstadt ; in Bohemia at Joachimsthal ; in Hungary at Schemnitz and Krem- nitz ; in Norway at Kongsberg. More rarely at Andreasberg, in Wheal Duchy, Dolcoath, and other Cornish mines, and formerly at Alva in Stirlingshire. It is the common ore at Guanaxuato, Zaca- tecas, and other places in Mexico ; in Peru, and at Blagodat in Si- beria. It is a valuable ore of silver, and so malleable, that King Augustus Family.'] STROMEYERITE REDRUTHITE. 473 of Poland coined medals out of some from the Saxon mines in its na- tive state. An earthy variety, the Silberschwartz or Silbermulm of the Ger- mans, of a dark bluish-black colour, is found in several of the above localities. 429. STROMEYERITE, Haidinger ; Sulphuret of Silver and Copper, Phillips ; Silberkupferglanz, Hausmann ; Isometric Copper Glance, Mohs. Rhombic, and isomorphous with copper glance ; crystals are rare, forming short prisms of ooP . ooPoo .OP . ^P . Poo . Usually massive, disseminated, or in plates. Cleavage not perceptible. Frac- ture flat conchoidal or even. Very sectile. H. 2*5 3; G. = 6-2 6-3. Lustre bright ; colour blackish lead-grey. B.B. fuses easily to a grey metallic, semimalleable globule ; shows reaction for copper with fluxes, and on cupelation with lead leaves a grain of sil- ver. Soluble in nitric acid with residue of sulphur. Chem. com. c'u + Ag , with 52-9 silver, 31-4 copper, and 15'7 sulphur. Analyses. Silver. Copper. Iron. pS. |*<*al. 1 52-27 2 5271 30-48 30-95 0-33 0-24 15-78 15-92 98-87 99-82 Stromeyer, Schlangenberg. Sander, Rudelstadt. 3 28'79 4 24-04 53-38 5394 2 : <>9 17-83 1993 100 100 Domeyko, S. Pedro, Chili. Do. Catemo, Do. 5 16-58 60-58 2-31 20-53 100 Do. Do. Do 6 12-08 63-98 2-53 21-41 100 Do. Do. Do. 7 2-96 7551 0-74 20-79 100 Do. S. Pedro, Do. The analyses of Domeyko, and an earlier one of Lampadius, who found 18'5 sulphuret of silver in a copper glance from Freiberg, show that the two components occur in indeterminate proportions, and hence are probably isomorphous, and both also dimorphous. It occurs massive with copper pyrites at Schlangenberg in Siberia ; crystallized at Rudelstadt in Silesia ; at Catemo in veins in porphyry with clay-slate. A variety with much iron is found at Cornbarvalla in Peru. It is used as an ore of silver and copper. 430. REDRUTHITE, N. ; COPPER GLANCE ; Vitreous Copper, Sulphuret of copper, Phillips ; Kupferglanz, Karsten ; Cuivre sulfure", Hauy ; Prismatic Copper Glance, Mohs. Rhombic; ooP (o) 119 35', P (P) with middle-edge 125 22' ; P (a) middle-edge 65 40'; 2Pao (rf) middle-edge 125 40'; Pao 0) middle-edge 65 48'. The usual combinations are OP . 0) ooP . 0) ooPoo O), OP . P . foo , or these with other faces (fig. 247), B r 474 KITPFEUINDTG. \Lead Glance Fig. 247. The crystals are mostly thick tabular, attached singly or in druses. The macles are united by ooP ; or by P when the tabular crystals intersect at an angle of 88. Usually it occurs massive, disseminated, in plates or lumps. Cleavage, prismatic along ooP imperfect. Fracture conchoidal or un- even ; very sectile. H. = 2-5 3 ; G. = 5-5 5-8. Lustre rather dull ; brighter on the streak. Colour blackish lead-grey, with a blue or other tarnish. B.B. colours the flame blue ; on charcoal in the oxidating flame sputters and fuses easily ; in the reducing flame becomes solid. With soda gives a grain of copper. Soluble in warm nitric acid, depositing sulphur. Chem. com. c'u? with 79'8 copper and 2O2 sulphur. Analyses. 1 2 3 4 ', Copper. Iron. Sul- phur. Silica. Total. 76-50 78-50 79-50 77-16 77-76 79-12 0-50 2-25 075 1-45 0-91 0-28 2200 18-50 19-00 20-62 20-43 20-36 075 1-00 99-00 100 100-25 99-23 99-10 99-76 Klaproth, Rothenburg. Do. Katherinenburg. Ulmann, Siegen. Thomson, Cornwall. Scheerer, Tellemark (G. = 5795). Do. Do. (G. = 5-521}. Hauy considered this mineral as hexagonal, but Mohs showed it to be rhombic. The crystals formed by fusing copper and sulphur are regular octahedrons, so that this substance must be dimorphous. Occurs with various other ores of copper and iron in the meta- morphic and stratified rocks, as at Freiberg in Saxony ; Rudelstadt in Silesia ; in Norway ; the Bannat ; Siberia, and the United States. Crystals are chiefly found in Cornwall, where very fine specimens have been obtained, especially in the mines near Redruth. Formerly at Frankenberg in Hessia it formed vegetable petrifactions, known as the Frankenberg Corn-ears, or argent en epis. In Scotland it occurs at Fassnet bum in Haddingtonshire, in Ayrshire, and in Fair Island, in small amount. It is one of the most important copper ores. Digenite of Breithaupt occurs massive, with G. = 4'568 4*680, but in other respects agrees nearly with Redruthite, According to a blowpipe analysis of Plattner, it contains 7O20 copper, 29-56 sulphur, and 0-24 silver (= 100), or 3 c'u + c'u- It is found at Sangerhausen in Thuringia and in Chili. 431. KUPFERINDIG, Breithaupt, Phillips, Mohs ; Covelline, Beudant ; Blue copper, Dana. Hexagonal ; ooP . OP, but crystals are rare. Usually it occurs Family. ,] EUKAIRITE BERZELINE. 475 massive, reniform, and fine granular. Cleavage, basal often very perfect. Sectile, and thin laminae flexible ; H. = 1-5 2 ; G. = 3 -g 3-85. Lustre dull resinous, inclining to metallic ; brighter on the streak. Colour indigo-blue, inclining to black ; streak black. B.B. burns with a blue flame ; on charcoal acts like redruthite, but remains fluid in the inner flame. Soluble in nitric acid. Chem. com. c'u with 66*7 copper, and 33'3 sulphur. Analyses. Cop- per. Iron. Lead. Sul- phur. Total. 1 2 6477 66-0 0-46 1-05 32-64 32-0 98-92 98-0 Walchner, Badenweiler. Covelli, Vesuvius. Covelli found this mineral on slags in the crater of Vesuvius, where he says it is formed by the action of sulphuretted hydrogen on chlo- ride of copper. It also occurs at Sangerhauseu, in the mines near Badenweiler, in the Wilden Schapbach in the Schwarzwald ; at Kielce in Poland, and crystallized with calc-spar on clay slate at Leogang in Salzburg. It differs in many respects from other metallic sulphurets. 432. EUKAIRITE, Berzelius, Mohs; Seleniuret of Silver and Copper, Phillips; Cuivre se'lenie argental, Hauy. Crystalline, but only massive and fine granular with indications of cleavage. Soft (cuts with the knife). Colour lead-grey. Streak shining. In the open tube forms a red sublimate of selenium and selenic acid. B.B. on charcoal fuses with sulphurous fumes to a brittle grey metallic grain. With borax or salt of phosphorus shows reaction for copper. With lead leaves a grain of silver. Soluble in nitric acid. Chem. com. Cu 2 Se + Ag Se, with 43 silver, 25-2 copper, and 31 '8 selenium ; or, by Berzelius' analysis, 38'93 silver, 23-05 copper, 26-00 selenium, and 8'90 earthy matter (= 96*88), which gives nearly 44*3 per cent, silver and 29*6 selenium. It occurs in a talcose or serpentine rock at the old copper mine of Skrickerum in Smoland. Its composition is analogous to that of stromeyerite, with the sulphur replaced by selenium. 433. BERZELINE, Beudant; Seleniuret of Copper, Phillips; Selen- kupfer, v. Leonhard, Mohs ; Cuivre selenie, Hauy. Crystalline, in thin dendritic crusts in fissures of calc-spar. Soft ; colour silver- white ; streak shining. In the open tube it forms a sub- limate of selenium and selenic acid, leaving copper. B.B. on char- coal fuses to a grey, slightly malleable bead, giving out strong odours 476 NAGYAGITE ALTAITE. \Lead Glance of seleninm. With soda after long roasting yields a grain of copper. Chem. com. Cu 2 Se, with 61-5 copper and 38'5 selenium ; or,byBer- zelius' analysis, 64 copper and 40 selenium (== 104). It occurs at Skrickerum, in Smoland, Sweden ; and rarely at the Caroline mine near Lerbach in the Harz. 434. NAGYAGITE, Haidinger; Black Tellurium, Phillips; Blatter- tellur, Hausmann; Foliated T., Allan; Nagyagererz, Werner ; Tellure natif auro-plombifere, Hauy ; Pyramidal Eutome- Glance, Mohs. Tetragonal ; P 140, f P 122 44\ The crystals tabular from pre- dominance of OP, occur attached, but are rare. In general only im- bedded in thin plates or foliated aggregates. Cleavage, basal very perfect. Very sectile, the thin laminae flexible. H. = 1 1-5 ; G. = 6 '85 7*2. Lustre splendent. Colour blackish lead-grey. In the open tube emits sulphurous acid and a white sublimate. B.B. on charcoal fuses easily, with white fumes, and forms a yellow deposit on the support. After long heating, leaves a grain of gold. Soluble in nitric acid with residue of gold, and in nitrochloric acid, leaving chloride of lead and sulphur. Analyses. 1 2 3 Lead. Gold. Silver. Copper. Tellu- rium. Anti- mony. Sul- phur. Total. 54-00 55-49 63-10 9-00 8-44 6-70 0-50 trace 1-30 1-14 1-00 32-20 31-96 13-00 4-50 3-00 3-07 11-70 100 100 100 Klaproth. Brandes. Berthier. From Klaproth's analysis, Berzelius considered this mineral as Pb Te, mechanically mixed with sulphuret of lead and tellur-gold. Berthier's analysis differs very widely. Petz has recently found 8.54, 7'81, and 6-48 per cent, gold, with none, or a mere trace of silver. It occurs in veins with gold and other ores at Nagyag in Siebenburg, and also at Offenbanya. 435. ALTAITE, Haidinger ; Tellurblei, G.Rose; Hexahedral Tellurium, Mohs. Tesseral ; massive in granular aggregates, with hexahedral cleav- age. Fracture uneven. Sectile. H. = 3 3'5 ; Gr. = 8'1 8'2. Colour tin-white inclining to yellow, with yellow tarnish. In the closed tube fuses, in the open tube forms round the assay a ring of white drops, and the fumes also form a white sublimate that is fusi- ble. B.B. on charcoal colours the flame blue. In the reducing flame fuses to a globule that almost wholly volatilizes, whilst the assay be- comes surrounded by a metallic shining ring, and at a greater distance Family."} HESSITE TETRAD YMITE. 477 by a brownish -yellow, volatile deposit. Easily soluble in nitric acid. Chem. com. Pb Te, nearly agreeing with an approximative analysis by G. Rose, who found 60*35 lead, 1-28 silver, and 38'37 tellurium (= 100). It occurs mixed with tellur-silver in the Sawodinski mine in the Altai mountains. 436. HESSITE, FrobeL Haidinger ; Tellur-silber, G. Rose ; Telluric Silver, Allan ; Uncleavable Tellurium, MoJis. Occurs massive and granular, with mere traces of crystallization. Slightly malleable ; H. = 2-5 3 ; G. = 8'31 8-83. Colour between blackish lead-grey and steel-grey. In the open tube it fuses, but does not fume, and gives only a very small sublimate of telluric acid. B.B. on charcoal fumes at a white heat, and leaves a rather brittle grain of silver. Ignited in the closed tube, with soda and charcoal powder forms telluride of sodium, which colours water deep- red. Soluble in warm nitric acid ; from the solution telluriate of silver crystallizes after some time. Chem. com. Ag Te, with 62'8 silver, and 37 -2 tellurium. Analyses. 1 9 3 4 Silver. Gold. Iron. Tellu- rium. Total. 62-42 62-32 61-55 46-76 6 : 69 18-26 0-24 0-50 ...a ...a 36-96 36-89 3776 34-98 99-62 9971 100 100 G. Rose, Altai. Do. Do. Petz, Nagyag (G. = 8'31 8-45. Do. Do. (G. =872 8-83. (a i Traces of iron, lead, and sulphur. Occurs at the Sawodinski mine in the Altai with pyrite, cuprite, and blende in talc-slate, and at Nagyag in Siebenburg, and used as an ore of silver or of gold. No. 4 the Tellurgoldsilber of Hausmann, the Petzite of Haidinger, is the same species, with part of the silver re- placed by gold. 437. TETRAD YMITE, Haidinger ; Telluric Bismuth, Phillips ; Tellur- bismuth, v. Leonhard; Rhombohedric Eutome- Glance, Mohs. Rhombohedric ; R 66 40'. The usual form is R . OR. The crys- tals almost always form double or quadruple raacles united by a face of R, and with the faces of OR inclined at 95. It also occurs massive and granular foliated. Cleavage, basal very perfect. Sectile, and in thin laminae flexible ; H. = 1 2 ; G. = 7-4 8 "5. Lustre dull ; co- lour between tin-white and steel-grey. B.B. on charcoal fuses easily, evolving sulphurous acid and occasionally odour of selenium, and staining the support yellow, and at some distance white ; at length yields a white grain of metal, which can be almost entirely volatilized. 478 MOLYBDENITE. {Lead Glance Soluble in nitric acid with residue of sulphur. Chem. com. 2 Bi Te 3 + Bi S 3 , with 59'66 bismuth, 35'86 tellurium, and 4-48 sulphur. Ana- lyses. Bis- muth. 1 60-00 2 58-30 3 61-15 4 79-15 Tellur 34-60 36-05 2974 15-93 Sul- phur. Sele- nium. Vein- stone. Silver. Total. 1 4-80 4-32 2-33 3-15 traces l'-48 075 2 : bV .99-40 99-42 95-29 99-71 Wehrle, Schubkau. Berzelius, Do. Wehrle, Deutsch-Pilsen. Damour, Brazil. 5 78-40 15-68 4-58 ... ... 98-66 Do. Do. The variety (1 and 2 above) from Schubkau near Schemnitz in Hungary, may be considered as a bismuth glance, in which part of the sulphur is replaced by tellurium. No. 3 from Deutsch-Pilsen in Hungary, the so-called Motybdan- silver of Werner, HLQ Elastic Eutome- glance of Mohs, is probably distinct. It is liglit steel-grey, splendent metallic lustre, one cleavage very perfect, and a second nearly at right angles less perfect ; the lamina are slightly elastic ; G. = 8-44 ; H. = 2-5. Nos. 4, 5 of a tellur-bismuth (the Bornite) found at Jose in Brazil in marble, give the formula 2 Bi Te + Bi S 2 . It occurs in thin, slightly flexible, and very brilliant laminae. At Schubkau the tetradymite occurs in a fissure in a trachytic con- glomerate ; and at Pojana in Siebenburg in hornstone with gold and auriferous pyrites. A similar mineral is known at Tellemark in Nor- way, and Bastnaes near Riddarhyttau in Sweden. 438. MOLYBDENITE, Beudant ; Sulphuret of Molybdena, Phillips; Molybdanglanz, v. Leonhard; Wasserblei, Werner; Molyb- dene, Hauy; Dirhombohedral Eutome-Glance, Mohs. Hexagonal, but dimensions unknown, being only found tabular or in short prismatic crystals of OP . ooP, or OP . P. Generally it occurs massive and disseminated, in scaly or curved foliated aggregates. Cleavage, basal very perfect. Very sectile, and thin lamina flexible. Feels greasy. H. = 1 1-5 ; G. = 4-6 4*9. Colour reddish lead-grey. Makes a grey mark on paper, a greenish mark on porce- lain. B.B. in the forceps, or on platina wire, colours the flame siskin- green, but is infusible. On charcoal yields sulphurous fumes, and forms a white coating, but burns slowly and imperfectly. It colours a bead of borax mixed with nitre, in the outer flame pale-brown, in the inner dark-brown. Decomposed by digestion in nitric acid, leaving a white powder of molybdic acid. In warm nitrochloric acid forms a greenish, in boiling sulphuric acid a blue solution. Chem. com. MO" with 60 molybdena and 40 sulphur. Analyses, next page. Family.] STIBINE. 479 Molyb- dena. Sul- phur. Vein- stone. Total. 2 3 4 5 60 59-6 59-42 58-63 57-15 40 40-4 39-68 40-57 3971 : 80 3-14 100 100 99-10 100 100 Bucholz, Altenberg. Brandes, Do. Seyhert, Chester, Pennsylvania. Svanberg and Struve, Lindas. Do. Do. Bohus. In their corrected analyses, Svanberg and Struve find the sulphur in the variety from Lindas in three trials = 40'933, 40-886, 40*867; and in that from Bohus, 40-996 ; and from these and other experi- ments make the atomic number of molybdenum 575-829. This mineral is common in small amount in various rocks, as gra- nite, gneiss, and chlorite slate, and in veins with tin and other ores. It occurs crystallized at Arendal, Numedal in Sweden, Greenland, at Shutesbury in Massachusets, Brunswick in Maine, Haddam in Connecticut, and other places. Also massive at Alteuberg, Ehren- friedersdorf, Zinnwald, Schlackenwald, the Mont Blanc mountains, and other parts of the Alps. In England it is found with apatite in the granite of Caldbeckfell in Cumberland, Shap in Westmoreland, in Wheal Goiiand, and in many other Cornish mines. In Scotland it has been found in granite at Peterhead, and at Corybuy on Loch Creran, and in chlorite slate in Glenelg. It much resembles graphite, but is readily distinguished by its streak, lustre, gravity, and action before the blowpipe. It is used for preparing the so-called blue car- mine for colouring porcelain. El. FAMILY. GREY ANTIMONY ORE. 439. STIBINE, Beudant ; Sulphuret of Antimony, Phillips; An- monglanz, v. Leonhard ; Grauspiessglaserz, Werner; Anti- moine sulfure, Hauy ; Prismatoidal Antimony Glance, Mohs. Rhombic ; P with polar edges 109 16' and 108 10', ooP 90 45'. The usual combination is ooP (m) . ooPoo (o) . P (P), either alone or with other forms, as P< (a), 2P2 (6), f P2 (e), P (s) (fig. 248). The crystals, mostly long prismatic or acicular, with strong vertical striae, are rarely distinctly formed or with perfect terminations. They are often combined in druses, or in diverging, stellar, or confused groups ; and also occur massive and disseminated in radiating, fibrous, or fine granular aggregates. Cleavage, brachydiagonal (o) highly perfect, the cleavage faces often horizontally striated ; also basal, prismatic along o>P, and macrodiagonal, but all imperfect. Sectile. 480 JAMESONITE. [Grey Antimony Ore Fig. 248. H. = 2 ; G. = 4-6 4-7. Cleavage faces brilliant. Colour lead-grey, with a blackish or iridescent tarnish. B.B. fuses easily, co- louring the flame green, and volatilizes, leav- ing a white coating on the support. In the open tube it yields a sublimate first of anti- monious acid, and then of oxide of antimony. Soluble in warm hydrochloric acid, except a small residue of chloride of lime. Decomposed by nitric acid, with precipitation of antimony oxide ; and also by solution of potash. Chem. com. Sb S 3 , with 72-9 antimony and 27'1 sulphur. Analyses. 1 2 :; 4 Antimony. Sulphur. Total. 74 7377 74-06 73-5 26 26-23 25-94 26-5 100 100 100 100 Bergmann. Thomson, Scotland. Davy. Brandes. Antimony glance occurs in beds or veins in granite, the metamor- phic and transition rocks, either alone, or with gold, silver, lead, and other ores. Its chief foreign localities are Braunsdorf near Freiberg in Saxony ; Wolfsberg in the Harz ; Przibram in Bohemia ; Felso- banya, Kremnitz, Schemnitz, in Hungary ; Auvergne in France ; in Spain, and various places in North and South America. It is found massive at St Stephen's, Padstow, and Endellion in Cornwall ; fibrous in greywacke at Glendinning in Dumfriesshire ; and in granite in Banffshire. It is the chief ore of antimony. 440. JAMESONITE, Haidingcr, Phillips ; Axotomous Antimony glance, Mohs. Rhombic ; ooP 101 20', other forms not accurately known. The crystals of the combination ooP . ooPoo are long prismatic, in paral- lel or radiating groups. It also occurs massive and columnar. Cleavage, basal very perfect, prismatic along ooP and brachydiagonal imperfect. Sectile. H. = 2 2'5 ; G. = 5'5 5'7. Steel-grey to dark lead-grey. B.B. decrepitates, fuses easily, and wholly volatilizes, except a small slag, which gives reaction for iron. Soluble in warm hydrochloric acid, with residue of chloride of lead. Chem. com. Pb' 3 sb'" 2 , with 43-7 lead, 36'1 antimony, and 20'2 sulphur. Ana- lyses, next page. Family,} ZINCKENITE PLAGIONITE. 481 Lead. Cop- per. Iron. Zinc. Bis- inii h. Anti- mony. Sul- phur. Total. 1 4075 2 3871 3 39-97 4 43-44 0-13 0-19 0-18 230 2C5 3-63 0-16 074a 0-42 T : 06 ...6 34-40 34-90 32-62 3547 22-15 22-53 21-78 17-20 0973 J9-72 99-48 100-01 H. Rose, Cornwall. Do. Do. Schaffgotsch, Spain. Pfaff, Nertschinsk. (a) Lead containing iron and zinc ; (6) + 3'56 arsenic. Jamesonite occurs in considerable masses in Cornwall with quartz and boumonite ; also at Valencia d 1 Alcantara in Estremadura in Spain ; in Hungary ; at Nertschinsk in Siberia ; and Catta franca in Brazil. The Bleischimmer of Pfaff, No. 4, from Nertschinsk, B.B. and with acids, acts like boulangerite ; but the analysis is uncertain, and it is probably an arsenious Jamesonite, or a mere mixture. 441. ZINCKENITE, G.Rose, Phillips; Bleianthnonerz, Weiss; Rhombohedral Dystome- Glance, Mohs. Hexagonal ; P 25 24' (Naumanri). The usual combination is ocP2 . P. The crystals, prismatic or acicular, vertically striated, and with three longitudinal furrows, or re-entering angles, are ar- ranged in diverging groups or in druses ; or form massive and colum- nar aggregates. Cleavage, prismatic but very imperfect. Fracture uneven. Rather sectile. H. = 3 3*5 ; G. = 5-30 5-35. Colour dark steel- grey to lead-grey, sometimes with a steel-blue or iridescent tarnish. B.B. decrepitates violently, fuses, emits fumes of antimony, and wholly volatilizes, except a small cupriferous remainder. In the open tube gives a sublimate of antimony oxide and antimoniate of lead. Soluble in warm hydrochloric acid, with residue of chloride of lead. Chem. com. Pb' sb"' with 35 lead, 43 - 4 antimony, 21*6 sul- phur ; or, by H. Rose's analysis, 31'84 lead, 0'42 copper, 44'39 an- timony, 22-58 sulphur (= 99'23). G. Rose and Hausmann consider this mineral as rhombic, the ap- parently hexagonal crystals being formed by a triple made. Brei- thaupt and Haidinger regard it as rhombohedric. It occurs at the Wolfsberg in the Harz, in a vein with stibine and quartz. Also, according to Walchner, near St Trudpert in the Schwarzwald. 442. PLAGIONITE, G. Rose, Phillips ; Hemiprismatic Dystome Glance, Mohs. Monoclinohedric ; C = 72 28', P 134 30' and 142 3', 2P 120 49'. Usual combination OP . 2P . P . P. The crystals are thick tabular, minute and grouped in small druses, or occur massive 482 B ou LANG E RITE. [Grey Antimony Ore and granular. Cleavage, hemipyramidal along 2P rather perfect. Brittle ; H. = 2-5 ; G. = 5 '4. Colour blackish lead-grey. B.B. decrepitates violently, fuses easily, sinking into the charcoal, and at length leaves metallic lead. In the open tube yields fumes of anti- mony and sulphurous acid. Chem. com. p D ' 4 sb'" 3 with 41 lead, 38'3 antimony, and 2O6 sulphur. Analyses. 1 2 Lead. Anti- mony. Sul- phur. Total. 40-52 40-98 3794 3753 21-53 21-49 99-99 100 H. Rose, Wolfsberg. Kudernatsch, Do, In chemical characters plagionite closely resembles jamesonite and zinckenite, and may be considered a compound of these two minerals. It was found at Wolfsberg in the Harz by Zincken, who named it Rosenite. 443. BOULANGERITE, Tliaulow. Occurs massive in fine granular, columnar, or parallel, radiating, or confused fibrous aggregates, and also compact. Slightly sectile ; H. = 3 ; G. = 5'8 6. Lustre silky, inclining to metallic. Co- lour blackish lead-grey, with darker streak. B.B. fuses easily, evolv- ing antimony vapours and sulphurous acid, and forming a coating of protoxide of lead. Partially soluble in nitric acid. Wholly in warm hydrochloric acid, with evolution of sulphuretted hydrogen. Chem. com. p D ' 3 sb'", with 58 lead, 24 antimony, and 18 sulphur. Analyses. Lead. 1 Iron. Cop- per. Anti- mony. Sul- phur. Total. 539 55-57 56-29 53-87 55-60 55-15 1-2 178 0-9 0-05a 25-5 24-fiO 25-04 23-66 25-40 25-94 18-5 18-86 18-22 19-11 1905 18-91 100 99-03 9955 98-47 100-05 100 Boulanger, Molieres. Thaulow, Nasafjeld. Bromeis, Nertschinsk. Bruel, Do. Abendroth, Ober-Lahr. Rammelsberg, Wolfsberg, G. 5756. (a) Silver; (b) G. = 5-96 in powder. This mineral occurs at Molieres in the Gard department in France ; at Nasafjeld in Lapland ; at Ober-Lahr in Sayn-Altenkirchen, and near Nertschinsk in Siberia. The Plumbostib of Breithaupt, also from Nertschinsk, is of a lead or steel-grey colour, curved columnar struc- ture, with a double cleavage; H. = 3*5 ; G. = 6-18. It contains 58'8 lead, with antimony, arsenic, and sulphur, and, according to Ber- zelius, is only boulangerite, the arsenic being probably accidental. The Embrithite of Breithaupt, from the same locality, in spheroidal, Family.'] GEOKRONITE STEINMANNITE PLUMOSITE. 483' fine granular masses of a lead-grey colour ; H. = 2' 5 ; G. = 6-29 6-31 ; contains, according toPlattner, 53*5 lead, 0'80 copper, 0-04 silver, with much antimony and sulphur, and is also probably bou- langerite. 444. GEOKRONITE, Svariberg. Rhombic ; P with polar edges = 153 and 64 45', ooP2 = 119 44' (?) according to Eerndt. Crystals are very rare of the combina- tion o>P2 . GoPoo . P. It mostly occurs massive, or compact with a striated or streaked lamellar structure. Cleavage prismatic along ooP2. Fracture conchoidal or even. Sectile. H. =2 3 ; G. = 6*45 6*54. Colour pale lead-grey, with a slight tarnish. B.B. fuses easily and volatilizes, showing the reaction for antimony, lead, sulphur, and sometimes also for arsenic. Chem. com. p'b 5 (sb'", AS'")- Analyses. 1 2 3 4 Lead. Cop- per. Iron. Anti- mony. Arse- nic. Sul- phur. Total. 66-45 64-89 66-55 68-87 1-51 1-60 1-15 0-42a 174 0-38 9-58 16-00 9-69 14-39 4-70 472 16-26 16-90 17-32 16-36 99-03 99-39 101-17 100 Svanberg, Sala. Sauvage, Meredo, G. 6*43. Kerndt, Tuscany, G. 6'45 6-4/. Apjohn, Kilbricken, G. 6-407. (a) + 0-11 zinc, with traces of silver and bismuth. Geokronite occurs in the silver mine of Sala in Sweden, at Meredo in Galicia in Spain with galena (Schulzite) ; and crystallized at Val di Castello near Pietrosanto in Tuscany. The Kilbrickenite of Apjohn, No. 4, from county Clare in Ireland, seems a massive, granular, or foliated variety. 445. STEINMANNITE, Zippe, Phillips ; Octahedral Lead Glance, Mohs. Tesseral, usual form the octahedron. It also occurs in botryoidal and reniforra aggregates with drusy surfaces, often showing distinct crystals. Cleavage hexahedral rather imperfect. Sectile. H. = 2-5 ; G. = 6-833, Zippe. Colour lead-grey. B.B. decrepitates vio- lently. On charcoal fuses readily, evolving sulphurous acid and fumes of antimony, and leaving a grain of lead and silver. Chem. com. sulphurets of lead and antimony in unknown proportions. It occurs with native silver, zinc-blende, pyrites, and quartz at Przibram in Bohemia. 446. PLUMOSITE, Haidinger ; Feather ore, Dana; Federerz, Werner ; Antimoine sulfur^ capillaire, Hauy. Crystallization unknown ; occurs in acicular or capillary crystals, 484 DUFRENOYSITE WOLFSBERGITE. \Grey Antimony Ore united in felt-like masses. Almost sectile. H. = 1 3 ; G. = 5*7 5'9. Lustre dull or glimmering. Colour dark-lead or steel-grey, sometimes with an iridescent tarnish. B.B. and with acids acts like zinckenitc. Fuses even in the flame of a candle. Chem. com. p' b 2 st/" with 49 '9 lead, 3O9 antimony, and 19 '2 sulphur. Analyses. Lead. Iron. Zinc. Anti- mony. Sul- phur. Total. 1 2 4ti-87 48-48 1-30 0'08 31-04 32-98 1972 20-32 99-01 10178 H. Rose, Wolfsberg. Poselger, Do. G. 5-6788, massive. It is found chiefly at Wolfsberg, but also at Andreasberg and Clausthal in the Harz, at the Pfaffenberg and Meiseberg near Neu- dorf in Anhalt, and at Freiberg and Scheninitz. 447. DUFRENOYSITE, Damour; Gotthardite, Rammelsberg. Tesseral ; the crystals composed of ooO . 2O2. Cleavage, not per- ceptible. Fracture uneven. Brittle. G. = 5'549. Colour steel- grey. Streak reddish-brown. In the closed tube gives a reddish- brown sublimate of sulphuret of arsenic. B.B. fuses easily, evolving sulphurous acid and arsenic fumes, and leaving a grain of lead. Slowly affected by hydrochloric acid, readily by warm nitric acid. Chem. com. p'b 2 AS'" with 57'12 lead, 20*74 arsenic, and 22-14 sulphur. Analyses. Lead. jSilver Cop- per. Iron. Arse-l Sul- nic. |phur. Total. 1 i 55-40 I 0-21 2 | 56-61 I 0-17 0-31 0-22 0-44 0-32 20-G9 ! 22-49 j 99'54| Damour. 20-87 | 22-30 I100-49J Do. This mineral is analogous in composition to plumosite, arsenic re- placing the antimony, but the hair-like crystals of the latter can scarcely belong to the tesseral system. It is found in small veins in the dolomite of St Gotthardt with realgar, zinc-blende, and pyrite. 448. WOLFSBERGITE, JV. ; Antimonial Copper, Dana ; Kupfer- antimonglanz, Zincken, Mohs. Rhombic ; ooP 135 12', ooP2 111. The crystals are tabular from predominance of the brachypinakoid, and usually broken at the ends. It is also found massive, disseminated, and fine granular. Cleavage, brachy diagonal very perfect, basal imperfect. Fracture conchoidal or uneven; H. = 3'5 ; G. = 4'748. Colour lead-grey to iron-black, sometimes with an iridescent tarnish. Streak black, dull. B.B. decrepitates, fuses easily, on charcoal emits fumes of antimony, and Family.'] KERMES BERTHIERITE. 485 after long fusion with soda gives a grain of copper. Chem. com. Cu Kb"' with 24-9 copper, 50-2 antimony, and 24-9 sulphur; or, by H. Rose's analysis, 24-46 copper, T39 iron, 0'56 lead, 46'81 antimony, and 26-34 sulphur (= 99-5S). It is found at Wolfsberg in the Harz imbedded in quartz. 449. KERMES, Beudanl ; Antimonblende, v. LeonJiard ; Red Antimony, Phillips ; Rothspiessglaserz, Werner ; Antimoine oxyde sulphure, Hauy ,- Prismatic Purple Blende, Mohs. Probably monoclinohedric (Naumann, Mohs). The crystals are acicular or capillary, and form diverging groups. It also occurs mas- sive and disseminated with a radiating fibrous texture. Cleavage, very perfect along the axis of the crystals, less perfect at right angles to it. Sectile; H. = 1 1-5; G. = 4-5 4'6. Semitranslucent ; lustre adamantine ; colour cherry-red ; streak similar. B.B. acts like antimonite. Soluble in hydrochloric acid, evolving sulphuretted hydrogen. In solution of potash the powder becomes yellow, and then wholly dissolves. Chem. com. sb"' 2 's'bi with 76-3 antimony, 19-0 sulphur, and 4-7 oxygen ; or 69*8 sulphuret and 30'2 protoxide of antimony. H. Rose in three trials found 75'06 antimony, 478 oxygen, and 20*49 sulphur (= 10O33). It is found in veins with antimonite and quartz, especially at Braunsdorf near Freiberg in Saxony ; also at Michelsberg and Przi- bram in Bohemia, and Allemont in Dauphine". The so-called Zundererz or Tinder-ore occurs in soft, flexible, tinder- like masses, of a dirty cherry-red or blackish-red colour, and little lustre. Borntrager found, in a variety from Andreasberg, 2 '56 silver, 43-06 lead, 4-52 iron, 16-88 antimony, 12'60 arsenic, 19'57 sulphur (= 99 "19). Hence it is not kermes as was generally supposed, but apparently a mixture, and, as 'shown by calculation, probably of plumosite (82-04 per cent J, mispickel (13'46), and pyrargyrite (4-34). 450. BERTHIERITE, Haidinger, Phillips, Mohs ; Haidingerite, Berthier. Crystallization unknown. It is found massive with a columnar or fibrous texture, and distinct cleavage in several directions ; H. = 2 3 ; G. = 4-0 4-3 (4-284 JBreit). Colour dark steel-grey, some- times yellowish or reddish ; very subject to tarnish. B.B. on char- coal fuses easily, evolving fumes of antimony, and at length leaves a black magnetic slag, which shows reaction for iron, and in some spe- cimens for manganese. Soluble in hydrochloric, and more readily in nitrochloric acid. Analyses, next page. 486 BISMUTHINE. {Grey Antimony Ore Anti- mony. Iron. Zinc. Man- ganese Sul- phur. Total. 1 52-0 2 54-34 3 54-70 4 58-65 5 61-34 16-0 11-96 11-43 12-17 9-85 0-3 trace 0-74 : 46 2-54 30-3 30-58 31-33 29-18 28-81 98-6 97-84 10074 100 100 Berthier, Chazelles. Rammelsberg, Braunsdorf. Do. Do. Berthier, Anglar. Do. Martouret. These analyses show that Berthierite consists of sulphuret of anti- mony sb'"i and sulphuret of iron p'e in various proportions, or in No. 1 as 2 : 3 atoms ; inNos. 2, 3, 4, as 1 : 1 ; and in No. 5 as 4 : 1. It occurs at Chazelles and Martouret in Auvergne, at Anglar in the dept. de la Creuse in France, at Braunsdorf in Saxony, and in veins at Tintagel and Padstow in Cornwall. In France it is used as an ore of antimony. 451. BISMUTHINE, Beudant; Sulphuret of Bismuth, Phillips ; Wis- muthglanz, Werner, 8fc. ; Bismuth sulfure, Hauy ; Prismatic Bismuth-glance, Mohs. Rhombic ; ooP 91 30'. The crystals are long prismatic or acicu- lar, with strong longitudinal stria3, and generally imbedded. It also occurs massive and disseminated in granular or columnar aggregates with a foliated or radiated texture. Cleavage, brachy diagonal per- fect, macrodiagonal less distinct, basal and prismatic along ooP im- perfect. Sectile ; H, = 2 2-5 ; G. = 6'4 6-6. Colour light lead-grey inclining to tin-white, with a yellowish or iridescent tar- nish. In the open tube yields a sublimate of sulphur, with odour of sul- phurous acid, and at length boils. B.B. on charcoal fuses easily in the inner flame, sputters, and yields a yellow coating with a grain of bismuth. Soluble in nitric acid, with residue of sulphur. Chem. com. Bi'" with 81*5 bismuth and 18*5 sulphur. Analyses. Bis- muth. Iron. Cop- per. Sul- phur. Total. 1 80-98 18-72 99-70 H. Rose, Riddarhyttan. 2 80-96 18-28 99-24 Wehrle, Retzbanya. 3 72-49 4 79-77 3-70 0-15 381 0-14 20-00 19-12 100 99-18 Warrington, Cornwall. Scheerer, Gjellebak, Norway. 5 74-55 0'40 3-13a 19-47 100-35 Hubert, Orawitza. ooO, ~, and others. The combinations are numerous, but in general either the tetrahedron, or the trigonal, or rhombic dodecahe- dron, appear as the prevailing form (fig. 249). Macles (fig. 250) are Fig. 249. Fig. 250. not uncommon. It is most abundant, massive and disseminated. Cleavage, octahedral imperfect, with traces in other directions. Fracture conchoidal to uneven, or fine granular. Brittle. H. = 3 4 ; G. = 4-3 5-2. Colour steel-grey to iron-black. Streak black, or dark-red in the variety containing zinc. Koasted in the open tube it yields fumes of antimony, sulphurous acid, and some- times arsenic. B.B. on charcoal boils slightly, and fuses to a steel- grey slag, usually magnetic, and with borax yields a grey metallic grain, which with soda gives copper. In nitric acid the powder forms a brownish-green solution, with evolution of nitrous acid, and a resi- due of antimony oxide, often also of arsenious acid and sulphur. Caustic potash partially decomposes the powder, the sulphuret of antimony and sulphuret of arsenic being dissolved, and thrown down by acids as an orange or citron-yellow precipitate. Chem. com. very variable, but generally ( c ' u , A ' gf F 'e, z'n, H' Y ) 4 (sb'", AS'")> Fran- kenheim. The pale varieties (Graugiltigerz} generally contain a large proportion of arsenic, sometimes even with no antimony ; the dark varieties (Schwarzgiltigcrz), on the other hand, less or no arsenic. Analyses, next page. 490 TENNASTTTE. [Grey Copper Ore Sul- phur. Anti- mony. Arse- nic. Cop- per. Iron. Zinc. Silver. Total. 1 1 2577 2 26-33 23-94 16-52 2-88 7-21 37-98 38- 63 0-86 4-89 7-29 2-76 0-62 2-37 99-34 98-71 H. Rose, Kapnik, Hungary. Do. Gersdorf, Freiberg. 3 26-83 12-46 10-19 40-60 4-66 3-69 0-oOa 99-44 Do. Markirchen, Alsace. 4 25-03 25-27 2-26 38-42 1-52 6-85 0-83 100-18 Do. Dillenburg, Nassau. 5 24-73 28-24 34-48 2-27 5-55 4-97 100-24 Do. Clausthal. 6 23-5-2 2663 25-23 3-72 3-10 1771 99-91 Do. Wolfach. 7 21-17 24-63 1481 5-98 0-99 31-29 98-87 Do. Freiberg. 8 23-76 2597 37-11 4-42 5-02 1 -096 98'38 Bromeis, Durango, Mexico. 9 23-34 10 24-17 18-48 27-47 398 3590 J5-80 4-90 1-89 1-01 6-05 traces c 0-33d 97-86 98-41 Scheidthauer, Iglo, Hungary. Kersten, Val di Castello. 11 24-1 26-8 357 4-5 8-9 e 100-9 Sander, Clausthal. 12 23-73 13 23-40 28'87/ 27-47 3878 3590 5-03 1-93 3 V 59 6-24 6'33g 100 100 Amelung, Camsdorf. Kersten, Angina, Tuscany. 'a) + 0'41 quartz ; (5) + 0'54 lead and 0'47 undecomposed mineral ; (c) with lead + 7" 52 mercury and 273 quartz ; (d) + 2-70 mercury ; (e) + 0'9 lead ; (/) with a little arsenic; &) + 2-70 mercury, and 2-03 veinstone, and loss. Nos. 1-7, 11, were crystallized ; Nos. 8, 12, massive; No. 13 had G. = 4*84, and, in a separate trial, the silver was found = 0'204 per cent., the gold = 0*0066 per cent. In a variety from Poratsch in Hungary, Klaproth found 6'25 mercury ; and this metal also occurs in that from Moschellandsberg. Vauquelin says he found platina in a variety from Guadalcanal in Estremadura. The varieties with much silver, like Nos. 6, 7, are the Weissgiltigerz, or silver- fahlore, chiefly from Freiberg. Lead seems a very rare component of this mineral, that in Nos. 8, 9, 11 being probably incidental. There are very many other analyses of this mineral, but the older ones are ge- nerally imperfect. The above are some of the chief foreign localities of this important ore. The largest crystals are, however, from the Cornish mines, especially Crinnis and others near St Austle. In Scotland it occurs in small amount in a few places, as at Airthrie near Stirling, and Sand- lodge in Zetland. 456. TENNANTITE, Phillips; Dodecahedral Dystome- Glance, MoJis. Tesseral ; resembling fahlore in forms, combinations, and macles. Cleavage dodecahedral along ooO, very imperfect. Brittle ; H. = 4 ; G. = 4-3 4-5. Colour blackish lead-grey to iron-black ; streak dark reddish-grey. B.B. decrepitates, burns with a bluish flame and odour of arsenic, and fuses to a magnetic slag. Chem. com. ( c 'u r'e) 4 AS'", and consequently an arsenical fahlore. Analyses. Sul- phur. Ar- senic. Cop- per. Iron. Zinc. Silver. Total. 1 30-25 2 27-76 3 29-18 4| 28-11 12-46 19-10 19-01 l-88 47-70 48-94 42-60 41-07 9-75 3-57 9-21 2-22 8-89 tracesa tracesft 100-16 99-45 100 99-51 Phillips, Trevisane, Cornwall. Kudernatsch, Do. Pearnley, Skutterud, G. = 4-53. Plattner, Freiberg. (a) + 0-08 quartz ; (b) with antimony, + 0'34 lead. Family.'] BOURNONITE. 491 Fig. 251. k Tennantite occurs in veins at "Wheal Jewel and Wheal Unity near Redruth and St Days in Cornwall. No. 3 is a similar mineral from Norway. No. 4 is the Kupferblende of Breithaupt, distinguished by its brownish-red or dirty chercy-red streak and lower specific gravity = 4'2 4-4 ; and by a portion of the copper being replaced by zinc. Properly these minerals are only varieties of fahlore. 457. BOURNONITE, Jameson, Phillips ; Schwarzspiessglaserz, Werner; Autirnoine sulfure plumbo-cuprifere, Hauy ; Dipris- matic Dystome- Glance, Mohs. "Rhombic; P 93 40', Poo 96 31', POD 92 52'. The most commoli combination is OP (r) . ooP (d) . ooPoo (s) . Poo (n) . oo Poo (K) . Poo (o) ; often with other faces, as in fig. 251, of a common form from Cornwall. The crystals are generally thick tabular, and very often macled, by a face of ooP, and several times repeated. It also occurs massive in granular aggre- gates, or disseminated and investing. Clea- vage, brachydiagonal imperfect ; macro- diagonal more indistinct ; and traces only in other directions. Fracture uneven to conchoidal ; rather brittle ; H. = 2 - 5 3 ; G. = 5*7 5'9. Lustre brilliant metallic. Colour steel-grey, inclining to lead-grey and iron-black. B.B. usually decrepitates and fuses easily, on char- coal at first fumes and then forms a black globule, which in a stronger heat colours the support first white, then yellow, and on removal of the lead by soda leaves a grain of copper. In the open tube evolves sulphurous vapours and white fumes, depositing above antimony oxide (volatile), on the lower side antimoniate of lead (not volatile and infusible). In nitric acid it forms a blue solution with residue of sulphur and oxide of antimony. Nitrochloric acid separates sulphur, chloride of lead, and antimoniate of lead. Chem. com. pV st/" + Cu 2 sb'", with 41-8 lead, 12'9 copper, 26 antimony, and 19 '3 sulphur. Analyses. Lead. Cop- per. Iron. Anti- mony. 24 23 25-00 28-50 26-28 25-68 29-4 28-3 Sul- phur. Total. 1 4262 2 41-66 3 39-00 4 1 40-84 5 41-38 6 38-9 7 40-2 12-80 13-33 13-50 12-65 12-68 12-3 13-3 1-20 rob 17-00 20-00 16-00 20-31 19-63 194 178 97-85 9999 98-00 10008 99-37 100 99-6 Hatchett, Endellion. Smithson. Klaproth, Nanslo, Cornwall. H. Rose, Neudorf, Harz. Sinding, Do. Dufr^noy, Alais. Do. Mexico. 492 WOLCHITE ~ FREIESIEBENITE. [Grey Copper Ore It occurs in veins in the crystalline schists and transition rocks along with quartz, galena, and various ores. The finest crystals are found in the Meiseberg near Neudorf in the Harz. It also occurs at Woifsberg, Clausthal, and Andreasberg, at Braunsdorf in Saxony, Ober-Lahr in Sayn-Altenkirchen, Kapnik in Siebenburg (where it forms the peculiar macles named Radelerz or Cog-wheel-ore), Servoz in Savoy, Alais and Pontgibaud in France, in Mexico, and Peru. It was originally discovered in Endellion parish near Redruth in Corn- wall by Count Bournon, who named it Enddlionite ; and is also found at Beeralston in Devonshire. 458. WOLCHJLTE, Haidinger ; Antimonkupferglanz, Breithaupt ; Prismatoidal Copper Glance, Phillips ; Prismatoidal Dystome Glance, Mohs, Rhombic ; but dimensions unknown. The crystals are short rhom- bic prisms, with the basis and a dome. It also occurs massive. Cleavage, brachydiagonal rather distinct. Fracture imperfect con- choidal. Brittle ; H. = 3 ; G. = 5-7 5-8. Colour blackish lead- grey. In the closed tube forms a sublimate of sulphur and sulphuret of arsenic, and fuses to a reddish-brown slag. B.B. on charcoal fuses with effervescence to a lead-grey metallic grain, which, roasted with soda, gives a grain of copper, colouring the support first white, then yellow. Schrotter found 29*90 lead, 17'35 copper, 1-40 iron, 16'65 antimony, 6'04 arsenic, and 28'60 sulphur (= 99'94). Rammelsberg remarks that this analysis does not lead to any for- mula, the sulphur being in excess for the metals which only require 25-23 per cent. It occurs in the iron mines at Wblch, or St Ger- traud, in the Lavant valley in Carinthia. 459. FREIESLEBENITE, Haidinger ; Sulphuret of Silver and Anti- mony, Phillips; Schilfglaserz, Freiesleben; Peritomous Anti- mony-Glance, Mohs. Rhombic ; ooP 1 00, Poo 130 8'. The crystals present rather com- plex combinations of various prisms and brachydomes. The prisms generally predominate, and often sliOAv curved reed-like faces, marked with strong vertical stria3. The macles intersect partly at right angles, partly obliquely, like those of staurolite. It also occurs massive and disseminated. Cleavage, prismatic along coP perfect. Fracture con- choidal or uneven. Rather brittle. H. =2 2-5 ; G. = 6 6 -4. Co- lour steel-grey inclining to dark lead-grey ; streak the same. B.B. on charcoal evolves sulphurous acid, deposits antimony and lead on the support, and leaves a grain of silver, which, with borax, sometimes shows reaction for copper. Chern. com. A '& sb'" + p'b 3 sb", with Family."] STEPHANITE. 493 22-5 silver, 32'4 lead, 26 '8 antimony, and 18*3 sulphur, part of the lead sometimes replaced by copper, Wbhler found 22*93 silver, 30*27 lead, 27*38 antimony, and 18*74 sulphur (= 99*32) as the mean of several analyses, one of which gave also 0*11 iron and 1-22 copper. This mineral is rare, and occurs chiefly in veins in gneiss, at the Himmelsfiirst and other mines near Freiberg in Saxony, where it is associated with galena, zinc-blende, antimonite, quartz, calc-spar, and other minerals. It is also said to occur at Kapiiik in Siebenburg, and Ratiborschitz in Bohemia ; at the latter, according to Zincken, containing bismuth. 460. STEPHANITE, Haidinger ; Brittle Sulphuret of Silver, Phillips; Brittle Silver ore, Allan; Sprbdglaserz, Werner; Argent an- timonie sulfure noir, Hauy ; Prismatic Melane-Glance> Mohs. Rhombic ; ooP (o) 115 39', P with middle edge 104 19', 2P middle edge 107 47'. The usual combinations are OP (s) . o>P(o) . Qt?), OP . P . 2Poo (d), and others (fig. 252), forming thick tabular or short prismatic crystals. Macles are frequent, united by a face of ooP, and Fig. 252. generally repeated three or four times. It also occurs massive, disseminated, and in various forms. Cleavage, do- matic along 2Poo and brachydiagonal, but both imperfect. Fracture con- choidal or uneven. Sectile. H. = 2 2*5 ; G. = 6-2 6*3. Colour iron- black to blackish lead-grey, rarely with an iridescent tarnish. Fuses in the open tube, and yields a sublimate of antimony oxide and arse- nious acid. B.B. on charcoal forms, with a weak odour of arsenic, a dark grey metallic globule, which in the reducing flame (especially with soda), yields a grain of silver. Easily decomposed in warm nitric acid, leaving antimony oxide and sulphur. Chem. com. \'s 6 S b'"> with 70*4 silver, 14 antimony, and 15*6 sulphur, but the silver partly replaced by iron or copper, the antimony by arsenic. Analyses. Silver. Iron. C pe?: Arse- nic. Anti- mony. Sul- phur. Vein- stone. Total. 1 2 66-5 65-50 5-0 5-46 3-75 *-> 5 3-30 10-0 12-0 19-40 1-0 1-00 95-0 98-41 Klaproth, Freiberg. Brandes, Do. 3 68-54 ... 0-64 14-68 16-42 ... 10028 H. Rose, Schemnitz. It has chiefly been found in Saxony at Freiberg, Schneeberg, Jo- hann-Georgenstadt, and Annaberg ; in Bohemia, at Joachimsthal and 494 POLYBASITE STERNBERGiTE. {Grey Copper Ore Przibram ; in Hungary at Schemnitz ; rarely at Andreasberg in the Harz, arid in many parts of Mexico, in Peru and Siberia. It has also been found massive and pulverulent at Wheal Duchy and Herland in Cornwall. It occurs in veins in crystalline, transition, and trachyte rocks, with arsenic, silver, and other ores, along with quartz, calc- spar, fluor spar, and heavy spar. It is a valuable ore of silver. 461. POLYBASITE, Rose, Phillips; Eugenglanz, Breithaupt; Rhom- bohedral Melane- Glance, Mohs. Hexagonal ; P 117 0'. The usual combinations are OP . ooP and OP . P ; the crystals always tabular, and often very thin. It also occurs massive and disseminated. Cleavage, basal imperfect. Sec- tile, and easily frangible. H. = 2 2 -5 ; G. = 6'0 6 '25. Colour and streak iron-black. B.B. decrepitates slightly and fuses very easily ; in the open tube yields sulphurous acid and a white sublimate ; and on charcoal a coating of antimony oxide. With fluxes shows re- action for copper ; and with soda gives a grain of cupriferous silver. With acids acts like bournonite. Client com. (A' S , c u) 9 (st>"', AS'"), but L. Gmelin says the copper occurs as c'u. Analyses. IT Silver. Cop- per. Iron.i Zinc. Arse- nic. Anti- mony. Sul- phur. Total. 64-29 72-43 69-99 9-93 3-04 4-11 0-06 ! ... 0-33 ! 0-59 0-29 ... 374 6-23 1-17 5-09 0-25 8-39 17-04 16-83 16-35 100-15 <)!)?) 100-30 H. Rose, Guarisamey. Do. Schemnitz. Do. Freiberg. Polybasite occurs in veins in the crystalline or transition strata, and in trachyte with stephanite, from which it was distinguished by G. and H. Rose. It is found in many mines near Freiberg in Saxony, at Joachimsthal in Bohemia, Schemnitz in Hungary, and Guanaxuato and Guarisamey in Durango, Mexico ; and is used as an ore of silver. 462. STEKNBERGITE, Haidinger, Phillips; Prismatic Eutome- Glance, Mohs. Rhombic ; P with middle edge 118 0', transverse section 119 30'. The crystals are usually thin tabular, from OP, bounded on the sides by P, 2Pco , or other forms, and occur in macles united by a face of ooP, or in fan-shaped, scopiform, and spheroidal groups. It is also found massive, with a flat columnar structure. Cleavage, basal very perfect. Sectile and flexible in thin laminae. H. = 1 1-5 ; G. = 4'2 4'25. Colour dark pinchbeck-brown, often with a violet-blue tarnish. Streak black. B.B. on charcoal emits odour of sulphur, and fuses to a magnetic globule covered with silver. With borax Family.] STANNINE. forms a glass coloured by iron, and a grain of silver. It is decomposed by nitrochloric acid, with residue of sulphur and chloride of silver. Zippe, in a variety from Joachimsthal, found 33'2 silver, 36 iron, and 30 sulphur (= 99 -2) ^_or very nearly 1 atom silver, 4 atoms iron, and 6 atoms sulphur, from which no formula can be deduced. Ber- zelius proposes A S + 2re'", with 32*7 silver, 33'6 iron, and 33-7 sulphur. In a variety from Schneeberg, Plattner found with the blowpipe 29'7 per cent, silver. It also occurs at Johann-Georgen- stadt in Saxony. The Flexible Sulphuret of Silver of Bournon is probably identical with sternbergite. Its very small crystals are, however, said to be monoclinohedric (C = 55), and appear like rhomboidal tables formed of ( ooPoo ), bounded on the sides by other forms. It has a very perfect clinodiagonal cleavage, is 'very soft, flexible in thin plates, and of a blackish colour Avith dull metallic lustre. It occurs in Hungary, and at Freiberg ; and, according to Wollaston, consists of silver, sulphur, and iron. 463. STANNINE, Beudant ; Sulphuret of Tin, Phillips ; Tin-pyrites, Allan ; Zinnkies, Werner ; Etain sulfure, Hauy ; Hexahedral Dystome-glance, Moh$. Tesseral. The hexahedral crystals are very rare, and generally it occurs massive, granular, and disseminated. Cleavage, hexahedral very imperfect. Fracture uneven or small conchoidal. Brittle. H. = 4 ; GL = 4-3 4'5. Colour steel-grey, sometimes inclining to brass-yellow (from copper pyrites). Streak black. In the open tube evolves white fumes and sulphurous acid. B.B. on charcoal fuses in a strong heat, becomes white on the surface, and forms close round the assay a white coating of peroxide of tin, which is not volatile. After roasting shows reaction for copper and iron, and, fused with soda and borax, leaves a pale, imperfectly malleable grain of copper. Easily decomposed by nitric acid, leaving tin peroxide and sulphur. The solution is blue. Chem. com. c'u 2 s n " + (r'e, z'n) 2 sn". Ana- lyses. Sul- phur. Tin. 26-5 2555 31-62 28-94 Cop- per. 30-0 29-39 23-55 26-31 Iron. Zinc. Lead. Vein- stone. Total. 1 30-5 2 29-64 3 29-93 4 2989 12-0 12-44 479 6-80 177 10-11 6-93 ! 41 l'-02 99-0 9981 100 99-28 Klaproth, Wheal Rock. Kudernatsch, Do. Johnston, St Michael's Mount. Rammelsberg, Zinnwald. Stannine occurs chiefly at Wheal Eock near St Agnes in Cornwall, where it forms a considerable vein, accompanied by pyrites and 496 CUPREOUS BISMUTH BISMUTHIC SILVER. BLENDE. [Blende blende ; and recently at Cam Brca, where it is sold as an ore of cop- per. The composition of No. 3 is peculiar, but the metals found would require 31*18 sulphur. At Zinnwald in the Erzgebirge, the only known locality out of Cornwall, it is associated with blende and galena, the lead being a mixture of the latter, and has G. = 4-506. The Cornish miners often -name it Bell-metal ore. Some crystals from St Agnes are said to belong to the rhombic system. 464. CUPREOUS BISMUTH, Phillips ; Kupferwismutherz, Klaproth ; Bismuth-Copper ore, Mohs. Rhombic probably ; occurs massive and disseminated ; occasion- ally in columnar aggregates apparently of rhombic prisms. Cleavage, distinct along a vertical plane. Fracture uneven and fine granular. Sectile. H. = 8*5 ; G. = 5. Colour steel-grey, with a light lead- grey tarnish. Streak black. In the open tube yields sulphur and a white sublimate. B.B. on charcoal fuses very readily, frothes, and stains the support yellow ; with soda gives a grain of copper. So- luble in nitric acid, with residue of sulphur ; the solution, if not too acid, forms a white precipitate with water. Klaproth found 34- 66 copper, 47-24 bismuth, and 12 '58 sulphur (= 94'48), and conjectured the loss to be oxygen. It was formerly found in cobalt veins in gra- nite near Wittichen in the Schwarzwald ; and in six-sided prisms at Wheal Buller in Cornwall. 465. BISMUTHIC SILVER, Phillips; Wismuthbleierz, Hausmann; Silver-Bismuth-Ore, Mohs. Crystallization unknown. Only found in delicate acieular or ca- pillary crystals ; or massive and disseminated. Sectile and soft. Colour pale lead grey, with darker tarnish. B.B. fuses easily, forms a large deposit on the charcoal, and evolves sulphurous acid. Soluble in nitric acid. Klaproth found 33 lead, 27 bismuth, 15 silver, 4'3 iron, 0'9 copper, and 16'3 sulphur ( 96'5). The specimen was from a vein in gneiss in the Schapbach valley in Baden, where it was wrought as an ore of silver and lead. V. FAMILY. BLENDES. 466. BLENDE, Werner, Allan ; Sulphuret of Zinc, Phillips ; Zinc- blende, Jameson ; Dodecahedral Garnet-Blende, Mohs. Tesseral and tetrahedral semitesseral ; the most common forms are -5, ~, (sometimes formed as O), coO, -^-, ooOoo, and others. Family.] BLENDE. 497 The combinations are very numerous ; and macles remarkably corn- Fig. 253. mon, united by a face of O, fig. 253, and fig. 78, p. 41 above. They are ge- nerally several times repeated, and the crystals so contracted as to appear much distorted. Frequently it occurs massive and granular, rarely radiating and very fine fibrous, and then reniform or botryoidal, and partly with a curved lamellar structure. Cleavage dodecahe- dral along ooO, very perfect. Very brittle ; H. = 3'5 4 ; G. = 3'9 4-2. Semitransparent to opaque. Lustre adamantine and resinous. Co- lour commonly brown or black, also red, yellow, and green. It is a very weak or non-conductor of electricity. B.B. generally decrepi- tates and often violently, but changes little, only fusing on very thin edges. In the oxidating flame in a strong heat deposits zinc oxide on the charcoal, which appears yellow when hot, but becomes paler when cold. Soluble in concentrated nitric acid, leaving sulphur. Chem. com. z'n with 66'8 zinc and 33'2 sulphur, but generally part of the zinc replaced by iron or cadmium. Analyses. Sul- phur. Zinc. Iron. Cad- mium. Vein- stone. Total. 1 32-63 66-63 074 ... ... 100 Thomson. 2 33-66' 66-34 100 Arfvedson. 3 33 6 63-0 3-4 .... 100 Berthier, Bagneres cle Luchon. 4 35-2 5.5-0 8-6 99-8 Lecanu. Cheionies. 5 2!-6 45-0 15-7 11-4 1007 Boussingault, Marmato. 6 33-0 61-5 4'0 1-5 1000 Berthier, England. 7 33-15 (51-40 2-29 1-50 98-34 Lowe, Przibram. 8 3275 6262 2-20 1-78 ^ 99-35 Do. Do. 9 32-10 64-22 1-32 trace : /2a 99-16 Kersten, RaibI, Car in Una. 10 33-73 53-17 11-79 0-746 99-43 Scheerer, Christiana. (a) = antimony and lead oxide, + 0-80 water ; (b ) manganese. The variety from Candado (No. 5) gives 77*5 sulphuret of zinc and 22*5 sulphuret of iron, and another from Salto, also near Marmato in Popayan, gave 76*8 of the former to 23-2 of the latter. This is very nearly 3 atoms to 1 atom, and Boussingault considers it a dis- tinct combination, which he names Marmatite ; but the other ana- lyses show that the iron only replaces part of the zinc. The yellow va- rieties are generally the purest, and have the highest specific gravity, = 4-107 4-111, Breithaupt ; whilst the brown with most iron have G. = 4-076 3*945, Brett. The latter are also easily known by the powder or small fragments after a short exposure B.B. on char- coal being attracted by the magnet. Gold is said to occur in some Tt 498 VOLTZINE ALABANDINE. [Blende blendes. The yellow foliated variety phosphoresces at a high tem- perature. This is a very common ore in many countries, and in various for- mations. Dark coloured crystalline varieties occur in Derbyshire, Cumberland, and Cornwall, where some from near St Austle contain cadmium. The most remarkable other localities in Europe are, for the green and yellow blendes, Frzibram, Schemnitz, and Kapnik ; the brown foliated, Freiberg, Schwarzenberg, Lautenthal, and Nagyag ; black blende, Freiberg, Zellerfeld, Kremnitz, and Schemnitz ; the ra- diated brown blende, Przibram and Kapnik ; the fibrous at Raibl, Freiberg, and Aix la Chapelle. In North America it is abundant, and fine brilliant yellow crystals occur in limestone at Lockport and Goat Island near Niagara. The black blende of Shelburne, N. H. is occa- sionally crystallized, and contains cadmium (3 per cent.) Very fine specimens are also found in Peru and Chili. This mineral has been used as an ore of zinc, but both in Cornwall and the Harz with very little success ; and it has also been attempted to produce the white or zinc vitriol and sulphuric acid from it in the latter place, and even to grind it up as a pigment. It is often highly prejudicial to the mechanical preparation of other ores ; and also to their reduction by smelting. 467. VOLTZINE, Fournet, Mohs. Occurs in small hemispherical incrustations, with a thin, curved- lamellar structure. Fracture conchoidaL H. = 4'5 ; G. = 3 '66. Colour brick-red inclining to yellow or brown. Opaque or semi- translucent. Lustre vitreo-resinous on the fractured surfaces, pearly on the divisional planes. B.B. acts like zinc-blende. Soluble in hydro- chloric acid with evolution of sulphuretted hydrogen. Chem. com. 4z'n + zn. Fournet's analysis gave 82'92sulphuret of zinc, 15'34 oxide of zinc, and 1-84 iron peroxide (= 10O10), and also a little of some resinous substance. It is found in a quartz vein at Rozieres near Pontgibaud in Auvergne. It agrees in composition with some slags from Freiberg, and Altenberg near Aachen, examined by Kersten. 468. ALABANDINE, Del Rio, Beudant; Sulphuret of Manganese, Phillips; Manganblende, Blumenbach; Manganese sulfure, Hauy ; Hexahedral Glance-Blende, Mohs. Tesseral ; O andooOoo ; but usually massive, granular, and disse- minated. Cleavage, hexahedral perfect. Fracture uneven, rather brittle. H. = 3 -5 4 ; G. = 3*9 4. Opaque ; lustre semime- tallic, duller when tarnished ; colour iron-black to dark steel-grey, with a brownish-black tarnish ; streak dark green. In the closed Family.] HAUERITE GREENOCKITE. 499 tube is unchanged, in the open tube becomes greyish-green. B.B. on charcoal, after long roasting in the reducing flame, fues with great difficulty to a brown slag. With borax gives reaction for manganese ; and is dissolved by salt of phosphorus evolving much inflammable gas. Soluble in hydrochloric acicl, giving out sulphuretted hydrogen. Chem. com. M'U, with 63*6 manganese and 36*4 sulphur ; or, by Arfvedson's analysis of a specimen from Siebenburg, 62*1 manganese and 37*9 sulphur ( 100). Klaproth found 82 protoxide of manganese, 11 sulphur, and 5 car- bon (= 98) ; and Del Rio 54-5 manganese, 39 sulphur, and 6*5 silica (=100), in a variety from Mexico, both differing much from the for- mula. It is found in veins with foliated tellurium, blende, and quartz at Nagyag and Kapnik in Siebenburg ; in Mexico, and in quartz veins in Minas Geraes in Brazil. 469. HAUERITE, Haidinger. Tesseral ; O, ooOoo , and ooO ; also O . ocOoo , sometimes with other faces. The crystals occur either single or in spherical groups. Cleav- age, hexahedral perfect. H. = 4 ; G. = 3 '463. Semitranslucent on very thin edges ; lustre metallic- adamantine ; colour reddish-brown to brownish-black ; streak brownish-red. In the closed tube yields sulphur, and leaves a green mass,, which B.B. becomes brown on the surface, and is soluble in hydrochloric acid. With fluxes acts like alabandine. Chem. com. Mn", with 46-28 manganese and 53*72 sul- phur. Patera found 42 - 97 manganese, 53*64 sulphur, 1-30 iron, and 1-20 silica (== 99*11), which, subtracting the silica and the iron as a bisulphuret, gives 45'2 manganese and 54*3 sulphur. It is found in clay with gypsum at Kaliuka near Altsohl in Hungary. 470. GREENOCKITE, Brooke and ConneL Hexagonal, and probably hemimorphic ; P 87 13', 2P 124 34'. The usual combinations are 2P . OP . ooP . P, or P . 2P . ooP. Only the upper half of the crystals is formed, and they are attached singly. Cleavage, prismatic along ooP imperfect, basal perfect. H. = 3 3-5 ; G. = 4'8 4*9. Translucent ; lustre brilliant resinous, or ada- mantine; colour honey or orange-yellow, rarely brown ; streak yellow. B.B. decrepitates and becomes carmine-red, but again yellow when cold. Fused with soda, it forms a reddish -brown coating on charcoal. Soluble in hydrochloric acid, evolving sulphuretted hydrogen. Chem. com. cd', or, by Thomson's analysis, 77*6 cadmium and 22*4 sulphur. Connel found 77*30 cadmium and 22*56 sulphur (= 99*86). It occurs iii a porphyritic amygdaloid near Bishoptown in Renfrewshire, and is named from Lord Greeiiock, its discoverer. 500 PYRARGYRITE. VI. FAMILY. RUBY-BLENDE. [Ruby-Blende 471. PYRARGYRITE, Glocker; Red Silver, Jameson, Phillips; Rothgiltigerz, Werner ; Argent antimonie sulfure", Hauy Rhombohedral Ruby-Blende, Mohs. Rhombohedric ; R 108 18' (Mohs) ; the other most important forms are, R, OR, 2R (r), R 3 , oo P2 (s), and R (I). The latter is generally formed as a trigonal prism, and the combinations, some- times very complex, are also occasionally hemimorphic. The crystals are generally prismatic (figs. 254, 255) ; but in the arsenical variety Fig. 254. Fig. 255. the scalenohedron R 3 often prevails. Macles are common of vari- ous kinds, but most frequently with the twin axis a polar edge of R. It also occurs massive, disseminated, dendritic, or investing. Cleavage, rhombohedric along R rather perfect. Fracture conchoidal to uneven and splintery. Slightly sectile, sometimes almost brittle. H. = 2 2-5. In this species, two varieties may be distinguished by the following characters : Light Pyrargyrite, or Arsenical Silver-Blende, Nau- mann. R = 107 48' 39", Breit. G. = 5-5 56. Cochineal to crimson-red. Streak aurora-red to cochineal-red. Dark Pyrargyrite, or Antimonial Silver-Blende, Nau- mann. R = 108 39' 39", Breit. G. == 5-75 5-85. Crimson -red to blackish lead-grey. Streak cochineal to cherry-red. Translucent on the edges to opaque. Chem. com. essentially A'g 3 sb" =59 silver, 23*5 antimony, and 17*5 sulphur. Semitransparent to translucent on the edges. Chem. com. essentially A'g 3 AS'" = 65-4 silver, 15*1 arsenic, and 19 '4 sulphur. Family.] MIARGYRITE. 501 B.B. on charcoal fuses easily, gives out sulphurous acid and antimony fumes, and leaves a grain of silver. Soluble in ni- tric acid, leaving sulphur and antimony protoxide. Solution of potash extracts sulphuret of antimony. Analyses, Nos. 1, 2,3. B.B. on charcoalfuses easily, gives out sulphurous acid and arsenical odour, and leaves a brittle me- tallic grain difficultly reduced to pure silver. Soluble in nitric acid, with remainder of sulphur and arsenious acid. Solution of potash extracts sulphuret of arsenic. Analysis, No. 4. Silver Anti- mony. Arse- nic. Sul- phur. Earthy mixture rotal. 1 58-95 22-85 Ifi-fil 0-30 9871 Bonsdorff, Andreasberg. 2 60-2 21-8 180 ... 100 Wohler, Mexico. 3 4 5745 6467 24-59 0-69 15 : 09 1776 19-51 ... 9980 99-93 Bottger, Zacatecas. H. Rose, Joachimsthal. The difference of the two varieties in angular dimensions still re- quires confirmation, and Zinckcn states that the light pyrargyrfte from Andreasberg contains no arsenic. Andreasberg is one of the chief localities of the dark red varieties, whilst the pale is rare. In Saxony, the former is common near Frei- berg ; the latter at Johann-Georgenstadt, Annaberg, Schneebcrg. and Marienberg. In Bohemia the light red occurs chiefly at Joa- chimsthal (a specimen from which, weighing above six pounds, and with crystals several inches long, is in the Prague Museum) ; the dark at Frzibram, and other mines. This variety also occurs at Schemnitz and Kremnitz in Hungary. Markirchen in Alsace, Kongs- berg in Norway, and many of the Mexican mines are other localities. Pyrargy rite has been found at W heal Brothers, and with native silver at Wheal Duchy in Cornwall. This is a very valuable ore of silver. It resembles red orpiment, but the latter has a lower specific gravity and yellow streak. From cinnabar it is distinguished by not volatilizing before the blowpipe. 472. MIARGYRITE, H. Rose, Phillips ; Hemiprismatic Ruby- Blende, Mohs. Monoclinohedric ; C = 81 36', P 90 53', P 95 59', and other partial forms. The rather complex combinations have a very pecu- liar, pyramidal, short prismatic, or tabular aspect (fig. 256). The Fig. 256. crystals are attached singly or form small groups ; and it also occurs massive and disseminated. Cleavage, indistinct traces in several directions. Fracture imperfect conchoidal or uneven. Sec- tile. H. = 2 2-5; G. =5-3 5-4. Opaque; or in thin splinters dark blood-red, translucent. 502 .XAJSTTHOKON. [Ruby-Blende Lustre metallic- adamantine. Colour blackish lead-grey, inclining to iron-black and steel-grey. Streak cherry-red. In the open tube fuses readily, yields sulphurous acid, and a sublimate of antimony oxide. B.B. with soda on charcoal leaves a grain of silver. With acids and solution of potash acts like the dark pyrargyrite. Chem. com. A 'g sb'", with 35'9 silver, 42-9 antimony, and 21 2 sulphur ; or, by H. Rose's analysis, 36'40 silver, 1-06 copper, 62 iron, 39-14 an- timony, and 21-95 sulphur (=99 17). The specimen was from a mine at Braunsdorf near Freiberg, where only this rare ore is known. Hausmann considers the Fahle Rothgiltigerz from Andreasberg as a miargyrite, with part of the antimony replaced by arsenic. It melts even in the flame of a candle, and is one of the richer silver ores. The Hypargyronblende of Breithaupt, from Clausthal, is pro- bably the same mineral. Plattner found in it 35 per cent, silver, with much arsenic and sulphur, some iron, and a little antimony. 473. XANTHOKON, Breithaupt, fyc. Rhombohedric ; OR . R and OR . R . 2R. The inclination of R : OR is 110 30', of -2R : OR 100 35'. The crystals appear as very thin hexagonal tables, with alternating oblique side faces. It also occurs in small reniform masses, with a crystalline granular structure. Cleavage, rhombohedric along R and basal, both more or less perfect. Rather brittle, and very easily frangible. H. = 2 2-5 ; G. = 5'0 5'2. Translucent and transparent ; lustre adaman- tine. Colour orange-yellow or yellowish-brown ; streak slightly darker. In the closed tube fuses very easily, becomes lead- grey, and yields a small sublimate of sulplmret of arsenic. In the open tube gives out sulphurous and arsenious acid. B.B. on charcoal evolves fumes of sulphur and arsenic, and leaves a grain of silver. Chem. com. A'g 3 AS"' + A'g 3 AS"'', with 63'4 silver, 14*7 arsenic, and 21-9 sulphur. Analyses. Silver. Iron. Arse- nic?. Sul- phur. Total. 1 2 64-18 63-88 0-97 13 '49 14-32 2136 21-80 100 | Plattner (brown var.; 100 Do. (yellow var.) This mineral is thus a compound of the light pyrargyrite with an analogous sulpho-arsenite ; and, according to Rammelsberg, the first instance of a double salt of sulphur with two acids. It occurs in the Himmelsfiirst mine at Freiberg. The Feuerblende of Breithaupt, in very delicate crystals, like those of stilbite, generally in scopiform groups, and with one perfect cleav- Family."} CINNABAR, 503 age, is probably identical. It is sectile and slightly flexible. H. = 2; G. = 4-2 4-3. Translucent, pearly adamatine, and hyacinth- red. B.B. acts like pyrargyrite ; and, according to Zincken, contains sulphur, antimony, and silver (=62-3 per cent., Plattner). It is found in the Kurprinz mine at Freiberg, and at Andreasberg. 474. CINNABAR, Jameson, Allan ; Sulphuret of Mercury, Phillips ; Zinnober, Werner ; Mercurblende, Naumann ; Mercure sul- fure, Hauy ; Cinabre, Beudant ; Peritomous Ruby-blende, Mohs. Rhombohedric ; R 71 47'. Common forms, OR, R, R, ccR. The ciystals appear rhombohedric or thick tabular ; they are chiefly small and conjoined in druses. It also occurs disseminated and gra- nular, compact, or earthy. Cleavage, prismatic along coR rather perfect. Fracture uneven and splintery. Sectile. H. = 2 2'5 ; G. = 8 8*2. Semitransparent or opaque. Lustre adamantine. Cochineal- red, with a lead-grey and scarlet-red tarnish. Streak scarlet-red. In the closed tube it entirely sublimes ; in the open tube sublimes, partly without decomposition, partly as metallic mer- cury, whilst sulphurous acid escapes. In the closed tube with soda it yields only mercury. Perfectly soluble in nitrochloric acid, but not in hydrochloric acid, nitric acid, or solution of potash. Chem. com. n'g, with 86-2 mercury and 13 '8 sulphur. In a variety from Japan, Klaproth found 84-50 mercury and 14'75 sulphur (= 99'25). In another from iNeumartel in Carniola, 85'00 mercury, and 14-25 sul- phur (= 99-25). Cinnabar occurs in the crystalline, transition, and secondary strata, in beds or veins, with native mercury, iron pyrites, and other ores. Its chief localities are Idria in Carniola, and Almaden and Alma- denejos in Spain, where Pliny says it was wrought under the name of Minium. Fine crystals are found in the coal formation at Wolfstein and Moschellandsberg in Rhenish Bavaria. It also occurs at Har- tenstein in Saxony ; near Clausthal in the Harz ; in several places in Carinthia ; Eisenerz in Styria ; Horzowitz in Bohemia ; Schem- nitz, Kremnitz, Szlana, and Rosenau in Hungary ; Ripain Tuscany ; in Siebenburg, in the Ural and Altai ; in China and Japan ; and in considerable abundance in California, Mexico, and Peru. This mineral is the principal ore of mercury, obtained either by sublimation or distillation. The purer varieties are used as a pig- ment. The fibrous cinnabar seems merely a mixture with marcasite. The Hepatic cinnabar of Phillips, or Lebererz of Werner, is also an inti- mate mixture with idrialite, carbon, and earthy matter. Its colour 604 REALGAR ORPIMENT. [Ruby- Blende is dark cochineal-red or lead-grey, and almost iron black. Streak red. G. = 6*8 7 '3. It occurs at Idria, partly compact, partly curved lamellar (Korallenerz) ; the latter sometimes described as a petrifaction. Elaproth found in it 81*80 mercury, 13 '75 sulphur, 2'30 carbon, 0'65 silica, 0'55 alumina, 0'20 iron peroxide, 0'02 cop- per ( = 99'27) ; or, according to Schrb'tter's estimate, 94'8 sulphuret of mercury, 2*5 idrialin, and 0'3 sulphuret of iron. 475. REALGAR, Phillips ; Red Orpiment, Jameson, Allan ; Rothes Rauschgelb, Werner ; Arsenic sulfure rouge, Hauy ; Hemi- prismatic Sulphur, Mohs. Monoclinohedric ; C = 66 44' (P), ooP (M} 74 23,' (Pec ) (n) 132, ooP2 (/) 113 20'. The crystals are short or long prismatic Fig. 257. (fi* 2>7), and attached singly or in druses. It also occurs massive, disseminated, and investing. Cleavage, basal and clinodiagonal, rather perfect, prismatic imperfect. Fracture small conchoidal to uneven or splintery. Sectile ; H. = 1/5 2 ; G. ' = 3'4 3'6. Semitrausparent or opaque. Lustre resinous. Colour aurora-red ; streak orange- yellow. Becomes negative electric by friction. In the closed tube it sublimes as a dark yellow or red mass ; in the open tube volati- lizes with a deposit of arsenious acid. B.B. on charcoal fuses and burns with a yellowish-white flame. Acids act on it with difficulty. In warm solution of potash it changes into a black powder. Chem. com. AS", with 70 arsenic and 30 sulphur. Klaproth found in a spe- cimen from the Bannat 68 arsenic and 30'5 sulphur {= 98'5). Lau- gier 69*57 arsenic and 30*43 sulphur (= 100). This mineral seems the Sandaracha of Dioscorides and Pliny It occurs in veins in rocks of various age. Fine crystals are obtained at Kapriik and Nagyag in Sicbenburg, and at Felsobanya andTajowa in Hungary ; less beautiful varieties at Andreasberg and Wolfsberg in the Harz ; and in the dolomite of St Gotthardt. Minute but well- formed crystals occur on Vesuvius and the Solfatara. The artificial preparation is used as a pigment. 476. ORPIMENT, Phillips ; Auripigmentnm, Pliny; Gelbes Rausch- gelb, Werner; Arsenic sulfure jaune, Hauy; Prismatoidal Sul- phur, Mohs. Rhombic; o>P 117 49', Po> 83 37'. The crystals usually short prismatic (fig. 258), occur in irregular masses or in druses. It is also found reniform, but most frequently disseminated in columnar or granular foliated masses. Cleavage brachydiagonal, very perfect ; Family.] SULPHUR. 505 Fig. 258. the planes striated vertically. Sectile, and in thin la- minae flexible ; H. = 1-5 2 ; G. = 3*4 3'5. Se- mitransparent or opaque ; lustre resinous or pearly on the cleavage planes. Colour citron-yellow to orange- yellow. Becomes negative electric by friction. In the closed tube yields a dark-yellow or red sublimate ; in the open tube burns and deposits arsenious acid. Fused with soda it yields metallic arsenic. Soluble in nitrochloric acid, in potash, and in ammonia, Chem. com. AS'", with 61 arsenic and 39 sulphur. Klaproth found 62 arsenic and 38 sulphur ; Laugier 61*86 arsenic, and 38-14 sulphur. This mineral occurs usually imbedded in clay along with realgar. Its more important localities are Tajowa near JSTeusohl in Hungary, various parts of Servia, Wallachia, Natalia, and Siebenburg ; at Hall in Tyrol, in granular gypsum ; in veins at Felsobauya, Kapnik, and Andreasberg ; in the dolomite of St Gotthardt ; at Braons in the Maritime Alps ; and at Zimapan in Mexico. In the Solfatara and similar places it seems a product of volcanic sublimation. At An- dreasberg it is sometimes produced from the decomposition of ores containing arsenic and sulphur ; and also during the roasting of silver ores. The pigment is mostly artificial. VH. ORDER. THE INFLAMMABLES. I. FAMILY. SULPHUR. 477. SULPHUR, Phillips; Schwefel, Werner; Soufre, Hauy ; Prismatic Sulphur, M6hs. Rhombic ; P with polar edges 106 38', 84 58', middle edge 143 17'; ooP 101 58'. Other common forms are OP, fP, Poo. The crystals are generally pyramidal from predominance of P (fig 259) ; F. 259 an d they are attached singly or in druses. It also occurs in reniform, spherical, or stalactitic incrustations, or massive, disseminated, or pulverulent. Cleavage, basal and prismatic along ocP imperfect Fracture conchoidal to uneven or splintery. Rather brittle. H. = 1-5 2-5 ; G. = 1'9 2-1. Transparent or translucent on the edges ; lustre resinous, or adamantine on the crystal u u 506 SELEN- SULPHUR. ^Sulphur faces ; colour sulphur-yellow, passing into honey-yellow, yellowish - brown, and red, or into straw-yellow, yellowish-grey, and white. In the closed tube it sublimes, at 227 Fahr. fuses, and at 518 takes fire, and burns with a blue flame, forming sulphurous acid. Chem. com. sulphur, occasionally more or less mixed with other substances. Mitscherlich observed that whilst the crystals formed by evaporat- ing a solution of sulphur in sulphuret of carbon were similar to those found in nature, those produced by the slow cooling of fused sulphur were monoclinohedric. But in certain circumstances melted sulphur also forms rhombic pyramids, as is seen in many of the sulphur ma- nufactories in the lower Harz. According to Frankenheim, the for- mation of one or the other kind of crystals depends on the tempera- ture, all produced at a temperature above 257 being monoclinohedric, those below this temperature either monoclinohedric or rhombic, but with more probability that they are rhombic the lower the tempera- ture falls. The clinohedric sulphur, when cooled, passes sooner or later into the rhombic. In certain circumstances both forms are de- posited from the same solution, which probably contains sulphur in two distinct conditions. Sulphur occurs especially in gypsum and the connected clays and marls ; also in the brown coal and carboniferous formations, and rarely in beds or veins in the transition or crystalline slates. It is very common in the craters of volcanos and solfataras. The finest crystals are obtained at Girgenti and other parts of Sicily along with celestine, and at Conil near Cadiz in Spain. Large masses occur in Poland, Sicily, theLipari Islands, the Solfatara near Naples, in Iceland and Java, The Sandwich Islands, Peru, and Chili, also furnish fine specimens. It is often deposited from springs, as at Aix la Chapelle, and in small amount from several in the coal formation of Scotland and of other countries. In 1844 nearly 148 million, and in 1845 96 million pounds avoirdupois of sulphur were procured in Sicily, of which Britain received about 40 million pounds. 478. SELEN- SULPHUR, Stromeyer. This mineral, of an orange-yellow or yellowish-brown colour, occurs on Vulcano, one of the Lipari islands, mixed with, or as the colouring matter of sal-ammonia. It fuses readily in the closed tube, and vo- latilizes. B.B. on charcoal burns, and gives out fumes of selenic and sulphurous acids. According to Stromeyer, it consists of sulphur and selenium, with a trace of arsenic, but is very little known. Native Selenium, according to Del Rio, occurs at Culebras in Mex- ico. It is brownish-black or lead-grey, and thin splinters are red translucent. H. = 2 ; G. = 4'3. Family^, DIAMOND. 507 II. FAMILY. DIAMOND. 479. DIAMOND; Demant, Werner; Diamant, Hauy ; Octahedral Diamond, Mohs. Tesseral and tetrahedral-semitesseral ; -% an< ^ "2 most ly oc " curring together and equally formed, o>O, ooOw, wzO, mOn ; or the octahedron, rhombic dodecahedron, and hexakisoctahedron, figs. 2, 3, 7, and 5, pp. 8, 9, are the more common forms. The crystals have often curved faces, and more or less approximate to spheres. They occur loose or imbedded singly. Macles are common, united by a plane of O, like fig. 253 p. 497 above, or with parallel systems of axes. Cleavage, octahedral perfect. Fracture conchoidal ; brittle. H. = 10 ; G. = 3-5 3-6. Transparent or translucent when dark-coloured. Refracts light strongly, and hence exhibits a fine play of colour. Lustre brilliant adamantine. Colourless, but often coloured in various white, grey, or brown tints, also green, yellow, red, blue, and rarely black. Becomes positive electric by friction. Burns in oxygen gas and forms carbonic acid. Chem. com. pure carbon. In 1675, Newton, from the optical properties of the diamond, con- jectured that it was an unctuous and combustible substance. This was confirmed by the experiments of Lavoisier and others, who found that it could be burnt by the sun's rays concentrated by a lens or mirror. Guyton de Morveau found that with iron it formed steel ; and Sir H. Davy proved that it was pure carbon without any mixture of hydrogen. Some, however, incidentally contain other substances, to which they owe their colour. In the ashes of burnt diamonds Petzholdt thought he could perceive traces of vegetable cells ; bat Wohler, who examined under the microscope a great number of dia- monds containing foreign matter, observed no traces of organic struc- ture. A crystal of a green colour heated before the blowpipe became brown, whilst some brown spots in another were not changed by igni- tion. Various opinions have been entertained regarding the origin of diamonds. Jameson conjectured they might be vegetable produc- tions ; Brewster thought this opinion confirmed by their optical pro- perties and analogy to amber. Liebig explains their formation by a process resembling putrefaction ; and Wohler asserts that they can- not have been formed in a high temperature, least of all by fusion. Their occurrence in the mica-slate of Brazil, perhaps also in that ot the Ural, is not favourable to their immediate vegetable origin. The chief localities where diamonds have been found are the East Indies and Brazil. In the former they occur in the district between 508 GRAPHITE. [The Coal Pennar, Sonar, and the delta of tlie_ Ganges (lat. 14 25) ; the mines forming five principal groups, or those of Cuddapah, the Pen- nar, Naudial, Ellora or Golconda, and Sumbhulpur. They are found in a sandstone rock, probably a recent formation. They also occur in Borneo and Malacca. In Brazil they chiefly occur in the district of Serro do Frio in the province of Minas Geraes, in a brown iron- stone, probably of recent origin ; but have lately also been discovered in the itacolumite, a variety of quartzose mica-slate. Tn 1829, and subsequent years, about fifty small diamonds were obtained from the gold sands of the Ural, probably derived from a mica-slate rock like that of Brazil. One or two have also been found in Georgia and North Carolina ; and in the Sierra Madre, south-west from Mexico, towards Acapulco. Among the largest known diamonds are the Pitt or Regent dia- mond, formerly among the crown jewels of France. In its rough state it weighed 410 carats (each 3'174 grains troy), but now only 136f carats, and has been valued at L.125,000. The diamond in the Russian sceptre weighs 194 carats, but is inferior to the former in water. Another, 1 inch 5| lines long, and 8 lines broad, but only partially polished, was presented by the Persian prince Chosroes to the Russian emperor. The Vienna collection contains a pale-yellow diamond weighing 139| carats. In Dresden there is one of a pecu- liar green colour. The largest stones are procured from the East Indies, those found in Brazil rarely exceeding 18 or 20 carats. Diamonds were first cut by Bergnem of Bruges in 1476. They are the most valuable of precious stones, being estimated at L.8 for one of one carat, and the price increasing as the square of the weight ; but this is merely nominal for the larger sizes. m. FAMILY. THE COALS. 480. GRAPHITE, Werner, %c. ; Plumbago, Phillips; Fer Car- bure, on Graphite, Hauy ; Rhombohedral Melan- Graphite, Mohs. Hexagonal, but only in thin tabular or short prismatic crystals of OP . ooP. Usually it occurs massive, and foliated, radiating, scaly, or compact ; also disseminated, or as a constituent of many rocks. Cleavage, basal perfect. Very sectile, flexible in thin laminae, and sometimes slightly malleable. Feels greasy. H. = 0'5 1 ; G. = 1-9 2-2. Opaque; lustre metallic; colour iron-black. Leaves a mark on paper. Is a perfect conductor of electricity. B.B. burns Family.'] ANTHRACITE. 509 with much difficulty ; in oxygen gas even less easily than the dia- mond ; and heated with nitre in a platina spoon only partially deto- Chem. com. carbon. Analyses. 1 2 3 4 5 6 Car- bon. Iron. Lime and alu- mina. 36-0 8-4 37-2 18-5 60 1-2 Water Silica Total. 53-4 71-6 62-8 81-5 94-0 98-9 7-9 5-0 2-7 15*0 100 100 100 100 100 100-1 Prinsep, England Do. Himalaya. Do. Ceylon. Do. Do. purified. Do. Do. crystallized. Do. Do. crystallized. Graphite was long considered a compound of carbon and iron in the proportion of 90'9 to 9*1, which Bertholet found in graphite formed in iron furnaces. Karsten and Sefstrom showed that it was pure carbon, the iron being a mere mixture, and the above analyses prove that it is often wanting. In a variety from Wunsiedel, Fuchs found only 0*33 per cent, ashes. Dumas and Stass observed that gra- phite carefully purified still left some sandy colourless grains when burnt ; and Erdmann and Marchand also noticed white wooly flakes of silica in the ashes. Graphite occurs crystallized at Pargas in Finnland, Arendal in Norway, Goldenstein in Moravia, Gopfersgrun in the Fichtelgebirge, Hollette in the Pyrenees, Ticonderoga in New York, in Ceylon, and other places. Griesbach near Hafherzell in Passau, Marbella in the south of Spain, and the Harz near Elbingerode in eurite porphyry, are other localities. The purest varieties are from Borrowdale in Cum- berland. In Scotland, it has been found in gneiss with garnets at Glenstrathfarrer in Inverness-shire, and in the coal formation at Craigman in Ayrshire. At the latter it is evidently common coal altered by contact with trap. Graphite is used for making pencils, the compact masses being cut into thin slips by means of fine saws. The powder mixed with sulphui* and gum was formerly employed for the same purpose ; but is now rendered compact simply by pressure in a vacuum. It is also used to form crucibles, which are capable of sustaining intense heat. The graphite from iron furnaces forms thin hexagonal tables ; and hence, as both it and the diamond are pure carbon, this substance must be dimorphous. 481. ANTHRACITE, Karsten, Phillips, Hauy ; Glance coal, Jameson Glanzkohle, Werner ; Harzlose Stein-Kohle, Non-bituminous coal, Mohs. Amorphous ; massive and disseminated, rarely in columnar forms, 510 ANTHRACIIE. [The Coal or fibrous and pulverulent. Fracture conchoidal ; brittle ; H. = 2 2-5 ; G. = 1-4 1-7. Opaque ; brilliant metallic lustre ; colour iron-black or greyish-black. Streak unaltered. Perfect conductor of electricity. Burns difficultly with a very weak or no flame, and does not cake. In the closed tube yields a little moisture, but no empyreumatic oil Detonates with nitre. Chem. com. carbon, with small proportions of oxygen and hydrogen, and traces of nitrogen ; also a mixture of silica, alumina, and peroxide of iron. Analyses in 100 parts Car- bon. Hydro- gen. Oxy- gen. Nitro- gen. Ashes . 90-45 2-43 245 4-67 Regnault, Pennsylvania. 2 92-56 3-33 253 1-58 Do. Valais. 3 91-98 3-92 3-16 0'94 Do. Mayenne. 4 91.45 4-18 2-12 2-25 Do. Herzogenrath, Aachen. 5 71-49 0-92 1-12 26-47 Do. Macot, Tarentaise. 6 89-77 1-67 3-63 0-36 4-57 Do. Lamure, Isere dpt. 7 90-58 3-60 3-81 0-29 1-72 Jacquelin, Coalbrook, Carmarthenshire. 8 87-22 2-49 1-08 2-31 6-90 Do. Sable", Sarthe dpt. 9 10 94-09 94-00 1-85 1-49 ... 2-85 0-58 1-90 4-00 Do. Vizille, Is6re dpt. Do. Isere dept. 11 94-10 2-39 1 : 34 0-87 1-30 Schafhautl, Pembrokeshire. 12 85-96 3-16 2-22 trace 7'07a L. Gmelin, Offenburg, 13 70-12 3-19 7-59 15-476 Kuhnert, Meissner. (a) + 1-59 water ; (&) + 3'63 water volatile at 212. There are many other analyses of anthracite. As the gaseous ele- ments, hydrogen, oxygen, and nitrogen increase, this substance ap- proaches nearer to common coal ; into which a gradual transition may be traced. The beautiful iridescent colours of some varieties arise from a thin coating of hydrated oxide of iron, and are at once destroy- ed by hydrochloric acid. Anthracite seems to be altogether uncrystalline, and in this to differ essentially from graphite. Hauy, however, states that it has a cleavage along the sides of an oblique four-sided prism, and even shows a tendency to form acute four-sided pyramids ; and Breithaupt that it has a rhombic crystallization with a basal cleavage. Its ori- ginal organic nature can scarcely be doubted. It frequently occurs where igneous rocks have intruded on common or brown coal, and then often forms columnar masses with their axes at right angles to the plane of contact. Many varieties also show vegetable structure under the microscope. Other anthracites, like the fibrous masses found in layers sometimes an inch thick in common or brown coal, must have a different origin. Karsten intimates that these may be portions of the original woody fibre from which the oxygen and hy- drogen had escaped before the mass was mineralized j or they may have Family.'] COMMON COAL. 511 arisen from plants containing less of these elements than those form- ing the remainder of the coal. The carbonaceous matter dispersed through the older stratified rocks, like that in the clayslates, and grey- wackes of the south of Scotland, is generally changed into anthracite. It is often found in trap or other igneous formations, as in the clay- stone porphyry of the Calton Hill at Edinburgh. It also occurs in beds of magnetite in the crystalline slates ; in hematite in the transition rocks ; and in clays as at Frankenberg in Hessia, either alone in nests, or along with copper and silver ores. It also forms veins either alone or with other minerals, as the graphite-like va- riety mixed with the silver ores at Kongsberg, Norway. Anthracite is very common in many parts of the English, Scottish, and Irish coalfields. It forms whole beds in the Alps, as in the Va- lais, Piedmont, Savoy, and Dauphine' ; in the Pyrenees, and in va- rious parts of France. In Germany it occurs in Silesia, Bohemia, Saxony, and the Harz, but not in very large amount. It is espe- cially abundant in the United States, as in Rhode Island, Massachu- sets, and above all in Pennsylvania, where it seems to be an altered portion of the common bituminous coal of the western states ; and it is also found with the oolite coal of Virginia. It is now used for ma- nufacturing metals, for economic, and even for household purposes. In 1847 the United States produced 2,982,309 tons, of which 1,650,831 tons were from Schuylkill, and 643,973 tons from Lehigh. 482. COMMON GOAL ; Black, Stone, Bituminous Coal, Phillips, Sfc. ; Schwarzkohle, Werner, tyc.; Houille, /fatty; Bituminous Stone- Coal, Harzige Steinkohle, Mohs. Structure compact, slaty, or confusedly fibrous ; often dividing into columnar, cubical, or rhomboidal fragments. Fracture conchoidal, uneven, or fibrous. Rather brittle or sectile. H. = 2 2*5 ; G. = 1-2 1*5. Lustre vitreous, resinous, or silky in the fibrous variety. Colour blackish-brown, pitch-black, or velvet-black. Burns easily, emitting flame and smoke, with a bituminous odour. Heated in the closed tube with powdered sulphur, gives out sulphuretted hydrogen. Chem. com. carbon, with oxygen, hydrogen, nitrogen, and earthy matters in various proportions. The following important table, con- taining the elementary analyses and economic value of British coals, is taken from the valuable report of Sir H. De la Beche and Dr L. Playfair. (Mem. Geol. Sur. vol. ii.) 512 COMMON COAL. [The Coal Spec. grav. Car- bon. Hydro gen. Nitro- gen. Sul- phur. Oxy- gen. Ash. Coke per cent. Eva- por. power r i 1-375 91-44 3-46 0-21 0-79 2-58 1-52 92-9 9-46 Anthracite. X 21 1-275 3 1-304 89-78 88-66 5-15 4-63 2-16 1-43 1-02 0-33 0-39 1-03 1-50 3-96 77-5 88-10 10-21 9-94 Ebbw Vale. Binea Coal. 4 1-326 88-26 4-66 1-45 1-77 0-60 3-26 84-3 10-14 Duffryn. 5 1-358 85-52 3-72 trace 0-12 4-55 6-09 85-0 6-36 Pentrefelin. js 8 1-30 84-87 3-84 0-41 0-45 7-19 3-24 85-5 9-35 Graigola. m 7 1-32 80-70 5-66 1-35 2-39 4-38 5-52 648 7-47 Ponty Pool. 8 1-34 75-15 4-93 1-07 2-85 5-04 10-96 62-5 8-84 | Rock vein. I 9 1-29 73-84 5-14 1-47 2-34 8-29 8-92 56-0 8-0 Coleshill. flO 1-277 74-55 5-14 0-10 0-33 15-51 4-37 49-8 7-08 Dalkeith jewel seam 4 11 1-316 76-94 5-20 trace 0-38 4-37 3-10 63-5 771 Do. coronation seam -ki 12 1-20 76-09 5'22 1-41 1-53 5-05 10-70 58-45 8-46 Wallsend, Elgin. V) 13 1-25 79-58 5-50 1-13 1-46 8-33 4-00 52-03 7-56 Fordel Splint. g 1 u 1-29 1-25 7985 81-70 5-28 6-17 1-35 1-84 1-42 2-85 8-58 4-37 3-52 3-07 56-6 59-2 7-40 7'3 Grangemouth. Broomhill. [of Dean Sue 1-283 73-52 5-69 2-04 2-27 6-48 10-00 57-8 8-52 Parkend, SydneyFor. I sh!7 1-59 80-03 2-30 0-23 6-76 in ash 10-80 90-1 9-85 Slievardagh. The following are a few foreign coals for comparison. Car- Hydro- Oxy- Earthy bon. gen. gen". matter. 1 96-02 0-44 2-94 0-60 Karsten, Werden, Westphalia. 2 89-16 3-20 6-45 1-18 Do. Eschweiler, Duren. 3 81-32 3-21 14-47 1-00 Do. Wellesweiler, Saarbriick. 4 5 78-39 73-88 3-21 2-76 17-77 20-48 0-63 2-88 Do. Beuthen, Upper Silesia. Do. Brzenskowitz, Do. 6 89-27 485 4-47tf 1-41 Regnault, Alais. 7 87-45 5-14 5-63a 1-78 Do. Rive de Gier. 8 84-83 5-61 6'57a 2-99 Do. Do. Cimetiere. 9 82-12 5-27 7'48a 5-13 Do. Lavasse. 10 76-48 5-23 16-Ola 2-28 Do. Blanzy. (a) Oxygen and nitrogen. The quality of some coals, as it were, to fuse and run together in the fire, or cake, as it is named, is supposed to depend on the amount of bitumen, or, as Karsten states, of the proportion of hydrogen to oxygen. It is usual to distinguish Slate-coal with a thick slaty struc- ture, and an uneven fracture in the cross direction ; Cannel coal with a resinous, glimmering lustre, and a large or flat conchoidal fracture, breaking into irregular cubical fragments, but more solid, and taking a higher polish than the other varieties ; Coarse or foliated coal, of a massive or lamellar structure, breaking into cubical or irregular angular masses, with a more splendent lustre, and less compact texture than the former, and more easily frangible ; Earthy coal, in loose pow- dery masses, often brown or dirty in colour, and apparently a semi- decomposed mass. This mineral occurs in most abundance in the so-called true coal formation, but coal not mineralogically different is found in other geological deposits, as for instance in the oolite at Richmond, Virgi- nia. It is abundant in many lands, as in England, South Wales, Family, ,] BROWN COAL. 513 Scotland, and Ireland ; in Belgium and France, in Germany and Southern Kussia. The United States possess immense fields in the valley of Mississippi. It is also found in China, Japan, Hindostan, Australia, Borneo, and several of the Indian islands, though probably not in all cases of uniform geological age. Its uses are too well known to need notice. The varieties with most carbon give out the most heat, but are more difficult to kindle, and require a stronger draft of air. For preparing gas those coals are best in which the hydrogen bears a high proportion to the oxygen, and which are free from sulphur or iron pyrites. 483. BROWN COAL ; Lignite, Jet, Phillips, fyc. ; Braunkohle, Erdkohle, Moorkohle, Pechkohle, Gagat, Werner, fyc. ; Jayet, Hauy ; Lignites, Dufrenoy. Distinctly vegetable in origin, the external form, and very often the internal woody structure, being preserved. The texture is com- pact, woody, or earthy. Fracture conchoidal, woody, or uneven. Soft and often friable. G. = 0'5 1/5. Lustre sometimes resinous, mostly glimmering or dull. Colour, brown, black, or rarely grey. Burns easily with an unpleasant odour. Colours solution of potash deep-brown. Heated with sulphur evolves much sulphuretted hy- drogen. Chem. com. like common coal, but with a large proportion of oxygen and hydrogen. Analyses in 100 parts. Carbon. Hydro- gen. Oxy- gen. Watr. Ashes. 1 48-85 2-62 18-23 24-80 5-50 L. Gmelin, Sipplingen. 2 70-49 5-59 18-93a . . 4-99 Regnault, Dax. 3 63-88 4-58 18-lla 13-43 Do. Grand-Racher, near Aix. 4 70-02 5 '20 21-77a f f 3-01 Do. Dept. Basses Alpes. 5 61 -20 5-00 24'78a 9-02 Do. Alpheus, Greece. 6 73-79 7-46 1379a 4-96 Do. Elnbogen, Bohemia. 7 7171 8 70-12 4-85 3-19 21-67a 7-59 3-636 1-77 15-47 Do. Meissner (Pechkohle). Kuhnert, Do. (Stangenk). 9 56-60 475 27-15 9-076 2-43 Do. Do, (Pechkohle). 10 60-83 11 57-26 4-36 4-52 24-64 26-10 9-366 10-796 0-81 1-33 Do. Hirschberg. Do. Habichtswald. 12 54-18 4-20 26-98 11-116 3-33 Do. Meissner. 13 63-35 5-68 2793a ... 3-04 Woskressensky, Tiflis. 14 47-46 4-56 33-03a ... 14-95 Do. Irkutsk. 15 20-60 2-75 1973a 56-92 Do. Kurland (Bltura. slate). (a) With nitrogen ; (6) volatile at 212 F. Brown coal presents many varieties. The Jet, or Pechkohle of Werner, is of a pitch-black colour, with a conchoidai fracture and re- sinous lustre. It often shows a distinct tendency to divide into pris- matic or columnar masses with four or six sides. The common brown coal is of a brown colour, and shows the woody texture with more or 514 PEAT. \_TJic Coal less distinctness. Sometimes it is foliated with impressions of leaves and fishes ; at other times earthy, like decomposed wood. Brown coal generally contains the leaves, branches, and stems of trees, sometimes entirely, at other times only in part converted into coal ; or they are partly coal, partly silicified or changed into iron ore. This kind of coal is found in the new red sandstone and kenper, more abundantly in the oolite (Brora and Yorkshire) and chalk, and in greatest profusion in the tertiary formations. Germany is very rich in brown coal deposits, especially in the north, in Thuringia, and on the Rhine. It is often connected with basalt or similar igneous rocks, as in the Meissner and other parts of Hessia. Hungary, France, Italy, and Greece also possess it in considerable abundance. The Surturbrand of Iceland seems a variety. It is used as fuel, but is much inferior to common coal, yielding less coke (35 50 per cent.), and being often very impure, so that it can only be burnt in particular kinds of stoves, or after being formed into masses like bricks and dried. In some districts it is em- ployed as manure ; and, where it contains much sulphuret of iron, for preparing alum. 484. PEAT ; Torf, Hausmann ; Tourbe, Beudant. This substance, consisting of a mass of more or less decomposed vegetable matter of a brown or black colour, is closely connected with the varieties of coal just described. Like them, it is rather a rock-mass than a simple mineral ; but, for the sake of comparison, we give the following analyses in 100 parts. Carbon. Hydro- gen. Oxy- gen. Nitro- gen, Ashes. 1 2 66-55 57-03 10-39 5-63 18-59 29-67 2-76 2-09 1-70 5-58 Fickenscher, Fichtelgebirge. Regnault, Vulcaire, Abbeville. 1 58-C9 5-93 31-37 4-61 Do. Long. 4 5779 6-11 30-77 5-33 Do. Champ-du-Feu. 5 fi 57-16 59-86 5-65 5-52 33-39 33-71 ... 3-80 0-91 Mulder, Friesland, compact. Do. Do. less compact. 7 50-85 4-64 30-25 ... 14-25 Do. Holland. Mulder has found among the proximate elements of peat four dif- ferent resins with humic and ulmic acid. The ashes, besides silica, alumina, and iron peroxide, contain the carbonate and phosphate of lime, and chloride of calcium. Peat shows a great attractive and re- tentive power for water, one part of dry turf absorbing two parts of water. Peat has been chiefly formed of five kinds of plants, the sphagnum, and similar mosses ; the stems and roots of heaths ; the similar parts of glumaceous plants ; the wood of trees, aided by some Family.] BITUMEN. 515 of the former ; and, lastly, of fuel and sea- weeds. The latter has been denied, but Hausmann states that beds of this nature occur on the coasts of Sweden and Norway, often 30 feet above the present level of the sea. or Thk > i UNIVERSITY IV. FAMILY. THE MINERAL RESINS. 485. BITUMEN, Naphtha ; Erdol, Steinol, Werner; Bittimine liquide, Hauy ; Naphte, Beudant. Fluid in various degrees ; colourless, yellow, or brown ; transpa- rent or translucent ; G. = 0*7 0*9. Volatilizes in the atmosphere with an aromatic bituminous odour. Easily inflammable, and burns with an aromatic odour. Chem. com. carbon and hydrogen in va- rious proportion, but usually about 1 C to 2 H. The very fluid transparent and light-yellow varieties are named Naphtha. Of these the following are analyses. Car- bon. Hydro- gen. Total. 1 2 3 4 5 6 7 84-65 88-02 85-40 877 86-4 85-96 82-2 13-31 11-98 14-23 13-0 12-7 14-04 14-8 97-96 100 99-63 101-0 99-1 100 97 Saussure, volatile portion, G. = 0753. Do. less volatile, G. = 0-836. Blanchet and Sell, more vol., G. = 0794. Do. less volatile part, G. = 0'849. Duii as. Hess. Thomson. Chemical research has shown that naphtha consists of various vola- tile combinations. In the variety from the Tegern lake in Bavaria v. Kobell found, besides pure naphtha, a volatile oil, a resinous sub- stance, and a considerable amount of paraffine. Gregory found the latter in the butter-like naphtha from Rangun in Hindostan. At this place there are said to be above 500 naphtha wells, producing a large amount of this substance. It is common in the vicinity of vol- canic mountains or mud volcanos, as at Baku on the Caspian Sea. China and Persia furnish it in considerable abundance. It is found at Amiano near Parma, and many other parts of Italy ; at Salies in the Pyrenees ; and in several places in the United States of North America. It is used for burning, for dissolving vegetable resins, and preparing varnishes. Petroleum includes the darker coloured yellow or blackish-brown, less fluid or volatile varieties. These appear a compound of naphtha and asphalt. Analyses, next page. 516 ELATERITE ASPHALTUM. I Mineral Resin Car- bon. Hydro- gen. Nitro- gen. Oxy- gen. Ashes Total. 1 88-3 2 887 11-9 12-6 0-011 0-04 ... 99-411 101-7 Boussingault, Bechelbrunn, Alsace. Hatten, Do. Do. 3 78-50 8-80 1-65 2-60 8-45 100 Ebelmen, Bastennes. This variety occurs in the cavities and fissures of many rocks, both stratified and volcanic. It is common in the coal formation of England, as at Ormskirk in Lancashire, at Coalbrookdale, Pitchford, and Madeley in Shropshire, and other localities ; and in Scotland at St Catherine's Well, south of Edinburgh. It also occurs in many other parts of Europe and in the United States. 486. ELATERITE, Hausmann ; Elastic bitumen, PJdllips ; Mineral Caoutchouc, Allan ; Elastiches Erdpech, Werner ; Uitume elastique, Hauy. Occurs in compact, reniform, or fungoid masses, elastic and flexible like caoutchouc. Very soft. G. = 0'8 1-23. Translucent on the edges or opaque ; resinous ; blackish, reddish, or yellowish-brown. Strong bituminous odour. Chem. com. CH 2 , with a little oxygen. Analyses. Carbon. Hydro- gen. Oxy- gen. Nitro- gen. Total. 1 2 3 4 B (J 7 52-25 58-26 85-47 84-38 83-67 85-96 86-18 7-50 4-89 13-28 12-58 12-54 12-34 12-42 40'10 36-75 015 010 1 0-00 100 98-75 96-96 96-21 98-30 98-60 Henry, Derbyshire. Do. Montrelais. Johnston, Derbyshire. Do. Do. Do. Do. Do. Do. Do. Do. Johnston considers the loss in his analyses as oxygen ; and Ram- melsberg also ascribes it to some compound containing this body. Elaterite is especially found in the veins of lead ore in the moun- tain limestone of Derbyshire ; but also at Montrelais near Nantes in France in carboniferous sandstone ; and at Woodbury in Connecticut in a bituminous limestone. 487. ASPHALTUM. Bitumen, Phillips in part ; Erdpech, Werner; Asphalte, Dufrenoy. Compact and disseminated in various forms. Fracture conchoidal, sometimes vesicular. Sectile. H. = 2; G. = 1.1 V2. Opaque, resinous, and pitch-black ; with strong bituminous odour, especially when rubbed. Takes fire easily, and burns with a bright flame and thick smoke. Not soluble in water. Soluble in ether, except a small Family.'] PIAUZITE. 517 remainder, which is dissolved in oil of turpentine. Chem. com. car- bon, oxygen, and hydrogen in uncertain proportions. Analyses. Carbon. Hydro- gen. Oxygen. Mitro- gen. Ashes. Total. 1 75-85 7-25 12-96 3-94 100 Regnault, Cuba. 2 79'18 9-30 8-72 2-80 100 Do Do. 3 76-13 9-41 10-34 2-32 1-80 100 Ebelmen, Auvergne. 4 77-64 7'86 8-35 1-02 5-13 100 Do. Abruzzi. .5 55-48 6-15 21-42 1-12 1583 100 Do. Pontnavey. 6 78-50 880 2-60 1-65 8-45 100 Do. Bastennes. 7 88-66 9-65 1-69 ... 100 Boussingault, Peru (ra. of 2). Asphalt seems in general a recent production, sometimes associated, but very often wholly unconnected with volcanic action. It is found in beds, veins, nests, or disseminated through various sandstone and limestone beds in the secondary, tertiary, and most recent for- mations. Occasionally it forms casts of shells, fishes, plants, or other organic remains. It is also found in mineral veins even in the oldest rocks, as in the beds of magnetite and haematite in Sweden. , The asphaltum of the Dead Sea was well known to the ancients, and pits near the Euphrates and Tigris furnished that used as mortar at Babylon. It is still abundant in Persia and other parts of Asia. The pitch lake of Trinidad, 1 mile in circumference, is another cele- brated locality. In cold weather the asphaltum near the sides is solid, and in some places trees are growing on the surface, but in the centre of the lake it is still soft and boiling. In 1843, a thick bed of asphaltum of considerable extent was discovered at Limmer near Hanover, a few feet below the surface. It is veiy abundant near Seyssel in the Ain department on the Khone ; and also occurs at Val Travers in Neufchatel, Lobsann in Alsace, in the Harz, and other places. It has been found in mineral veins in Cornwall ; in veins in Haughmond hill, Shropshire ; in ironstone nodules in East Lothian ; and in irregular masses in the carboniferous limestone near Burnt- island in Fifeshire. 488. PIAUZITE, Haidinger. Massive, but with many parallel fissures ; fracture imperfect con- choidal; sectile. H. = 1*5 ; G. = 1-22. Dimly translucent on very thin edges ; lustre resinous ; colour blackish-brown ; streak yellow- ish-brown, fuses at 600 Fahr., and burns with a peculiar aromatic odour, a lively flame, and much dense smoke. Perfectly soluble in ether and caustic potash. It is found in vein-like masses in the brown coal at Piauze north of Neustadt in Carniola. 518 IXOLYTE AMBER. [Mineral Resin 489. IXOLYTE, Haidinger. Massive and amorphous, with conchoidal fracture. H. = 1 ; G. = T008. Lustre resinous; colour hyacinth-red; streak ochre-yellow. Rubbed between the fingers it emits an aromatic odour, and becomes soft at 169, but is still viscid at 212. Found in fissures of the brown coal at Oberhart near Gloggnitz in Austria. 490. AMBER, Phillips ; Bernstein, Werner; Succinite, Breithaupt ; Succin, Hauy ; Yellow Mineral Resin, Mohs. Occurs in round irregular lumps and grains, or in drops and appa- rently indurated fluid masses. Fracture perfect conchoidal. Slightly brittle. H. = 2 2-5 ; G. = 1 1*1. Transparent to translucent or almost opaque ; lustre resinous ; colour honey -yellow, but some- times hyacinth-red or brown, at other times yellowish-white, and occasionally streaked or spotted. When rubbed it emits an agreeable odour, and becomes negatively electric. It melts at 550, emitting water, an empyreumatic oil, and succinic acid. It burns with a bright flame and pleasant odour, leaving a carbonaceous remainder. Only a small part is soluble in alcohol. Chem. com., according to Schrotter, C 10 H 8 O, with 79 carbon, 10'5 hydrogen, and 1O5 oxygen. Ana- lyses. 1 2 Car- bon. Hydro gen. Oxy- gen. Lime. Alu- mina. Silica. Total. 80-59 78-82 7'31 10-23 6-73 10-95 1-54 1-10 0'63 97'90 Drapiez, Trahenieres. 100 | Schrotter. The proximate elements of amber consist of the succinic acid, two resins soluble in alcohol and ether, and in greatest amount of a bitu- minous substance insoluble in alcohol, in oils, or in caustic potash. The chemical properties and mode of occurrence of amber leave no doubt of its being the produce of extinct coniferae. It has been found incrusting or penetrating fossil wood, exactly like resin at the present day, and enclosing the cones and leaves of the trees. Numerous in- sects, the inhabitants of these ancient forests, have been embalmed in a similar manner. To the tree which principally produced it, Goppert gives the name of Pinites suctinifer, but probably there has been more than one species. It is often stated to occur in the brown coal beds of Northern Germany, but Goppert says that he knows of no instance of this, the substance he found in these beds being retinite, whilst the amber is always in the drifted sand and gravels above, associated with wood, also apparently water-worn and drifted. It is also said to have been observed in the newer secondary formations, as by Dunker in Family.'] RETINITE. 519 the conglomerate sandstone of the lower oolite at the Porta West- phalica near Minden ; by Pfaff in the gypsum of the Segeberg in Hoi- stein ; and by Glocker in the coal connected with the greensand near Trubau, Walchow, and other places in Moravia. The finest amber, often highly transparent, and showing blue or opalescent tints, occurs on the Sicilian coast between Catania and Semito. It is found most abundantly, and in the largest masses, ge- nerally of yellow, far more rarely of white tints, on the Prussian coast, especially between Palmnicken and Gross-Hubenicken, from which point it decreases on both sides. It is also thrown on shore by storms, or fished up with the sea-weed. In East and West Prussia there is scarcely a village where it has not been found, and it extends thence into Brandenburg, Pommerania, Mecklenburg, and Holstein, to the low land of Saxony and Silesia, to Poland, Galicia, Volhynia, Li- thuania, Esthonia, and the whole Baltic plain. It has also been found in Southern Germany, in France, Italy (near the Po), Spain, Sweden, and Norway. In other quarters of the globe, the shores of the Caspian Sea, Siberia, Kamtschatka, China, Hindostan, Madagas- car, North America, and Greenland are mentioned as localities. In Britain it is thrown out by the sea on the shores of Norfolk, Suffolk, and Essex, and has also been met with in the sands at Kensington near London. Amber is used for ornamental purposes, and for preparing succinic acid, and varnishes. A specimen, 14 inches long, and weighing about 14 Ibs., was found in 1803 near Gumbinnen, and is now in the Berlin Museum. It is valued at 10,000 dollars, or L.1500 sterling. 491. RETINITE, v. Leonhard, frc. ; Retinasphalt, Hatchett, Phillips, Mohs ; Kesinite, Hauy. Occurs in roundish or irregular lumps. Fracture uneven or con- choidal. Very easily frangible ; H. = 1-5 2 ; G. = 1/05 1'15. Translucent or opaque. Lustre resinous or glistening. Colour va- rious shades of yellow or brown. It usually melts at a low heat and bums with an aromatic or bituminous odour. Chem. com. in gene- ral, carbon, hydrogen, and oxygen, but in very uncertain amount ; this name having been given to various fossil resins. Analyses. Soluble in alcohol. Not sol. in alcohol. Earthy matter. Total. 1 55 2 59-32 3 91 4 55-5 41 27-45 9 42-5 3 13-23 iVs 99 100 100 99-5 Hatchett, Bovey. Johnston, Do. Bucholz, Halle. Troost, Cape Sable. 520 WALCUOWITE COPALINE BEEENGELITE. [Mineral Resin Hatchett thought that the mineral from Bovey consisted of a resin- ous substance and another like asphalt, and hence named it Retin- asphalt ; but Johnston states that the portion soluble in alcohol is not similar to asphaltum. It is found in the above and other loca- lities usually in beds of brown coal ; but near Osnabrtick forms a layer in peat. 492. WALCHOWITE, Haidinger. Occurs in rounded pieces several inches in size, with a conchoidal fracture ; H. = 1-5 2 ; G. = T035 1/069. Translucent, re- sinous ; colour yellow, with brown stripes ; and a yellowish-white streak. It fuses at 482, and burns readily. Soluble partially (7 '5 per cent.) in ether ; and in sulphuric acid forms a dark brown solution. Chem. com. C 12 H 9 O, with 80'4 carbon, 107 hydrogen, and 8'9 oxygen, according to Schrotter's analyses. It occurs in brown coal at Walchow in Moravia, and was formerly thought retinite or copaline. Boussingault found a similar mineral near Bucaramanga in New Granada. 493. COPALINE, Hausmann ; Fossil Copal, Highgate Resin, Aikin, Jameson ; Copal fossile, Dufrenoy. Occurs in irregular fragments; H. = 1*5 ; G. = 1'046. Trans- lucent, resinous, and light-yellow or yellowish -brown. Burns easily with a bright yellow flame and much smoke. Alcohol dissolves very little of it, which is precipitated by water. Becomes black in sul- phuric acid. Chem. com. C 40 H 64 O ; or, by Johnston's analyses (mean of two), 85-54 carbon, 11-63 hydrogen, 2-76 oxygen, 0'14 ashes (= 100*07). It is found in the blue clay at Highgate near London. Johnston describes a somewhat similar resin from the lead mines of Settling Stones in Northumberland, where it is found in flat drops or crusts on calc-spar. It is infusible at 500 F., and has G. = 1-16 1-54; and contains by analysis 85'13 carbon, 10'85 hydrogen, and 3*26 ashes, for which he proposes the formula C 2 H 3 . 494. BERENGELITE, Johnston. Occurs in large amorphous masses with conchoidal fracture. Co- lour dark-brown inclining to green. Yellow streak. Has a resinous unpleasant odour and bitter taste. Fuses below 212, and then con- tinues soft at ordinary temperatures. Easily soluble in alcohol ; the solution has a bitter taste. Chem. com. C 40 H 62 O 8 . Mean of two analyses, 72-40 carbon, 9-28 hydrogen, 18'31 oxygen. It is said to form a lake in the province of St Juan de Berengela in South Ame- rica Family.'] GUYAQUiLLrrE HARTINE MIDDLETONITE, &c. 521 495. GUYAQUILLITE Johnston. Occurs in large amorphous masses, yielding easily to the knife, and very friable; G. = 1-092. Colour pale-yellow; lustre slightly re- sinous. At 157 it begins to melt, and is quite fluid at 212. Be- comes viscid when cold. Slightly soluble in water and largely in alcohol, forming a yellow fluid with a bitter taste. Forms a reddish- brown solution in sulphuric acid. Chem. com. C 20 H 26 O 3 . Mean of two analyses by Johnston, 77'01 carbon, 8'18 hydrogen, and 14-80 oxygen. Found at Guyaquil in South America. The Bogbutter described by Williamson, from the Irish peat mosses, is a similar compound. It melts at 124, is easily soluble in alco- hol, and contained 73-78 carbon, 12-50 hydrogen, and 13*72 oxygen. 496. HARTINE, Schrotter. Occurs in spermaceti- like masses ; G. = 1-115. Colour white ; without taste or smell. Becomes soft at 392, and at 410 melts to a clear yellow fluid, being at the same time partly decomposed. Burns with a bright flame. It is not soluble in water, very little in ether, and less in alcohol. Petroleum dissolves a larger amount, which afterwards crystallizes in longneedles. Chem. com. C 20 H 34 O 2 ; or, by Schrotter's analysis, 78'26 carbon, 10'92 hydrogen, 10-82 oxygen. It occurs in the brown coal of Oberhart near Gloggiiitz in Austria. 497. MIDDLETONITE, Johnston. Occurs in small round masses or thin layers. Brittle, but easily cut with a knife ; G. = 1-6. Transparent in small fragments ; lustre resinous. Colour reddish-brown by reflected, deep-red by trans- mitted light. Streak light-brown. It becomes black on exposure to the atmosphere. Not altered at 400 F., but fuses at higher tempe- ratures, and burns like resin on hot coals. Alcohol, ether, and oil of turpentine dissolve a small portion by boiling, and become yellow. Soluble in concentrated sulphuric acid. Chem. com. C 20 H 20 -f- H O ; or, by Johnston's analysis, 86'44 carbon, 8'01 hydrogen, 5'56 oxygen. Found in the main coal seam at Middleton near Leads, and at New- castle. 498. OZOKERITE, GlocJter, Phillips, Dufrenoy. Amorphous, but sometimes fibrous. Fracture in one direction flat conchoidal, in another splintery. Very soft, pliable, and easily fash- ioned with the fingers. G. = 0'94 0-97. Lustre glimmering or glistening on the chief fracture ; semitranslucent ; yellowish-brown or hyacinth -red by transmitted, dark leek-green by reflected light ; it xx 522 HATCHETINE FiCHTELiTE HARTiTE. [Mineral Resin has a pleasant aromatic odour; fuses easily (at 14A,Schrditer; at 183, Malagutti) to a clear oily fluid, again becoming solid when cold, and at higher temperatures burns with a clear flame, seldom leaving any ashes. Readily soluble in oil of turpentine, with great difficulty in alcohol or ether. Chem. com. CH, with 85*7 carbon and 14-3 hy- drogen. It occurs in a bituminous sandstone near coal and rock salt at Slanik and Zietriska in Moldavia ; and, according to Partsch, at Gersten near Gaming in Austria. Also in the coal mine of Urpeth near Newcastle-on-Tyne in England. Analyses. Carbon. Hydrogen. Total. 1. ... 85-75 ... 15-15 ... 100-90 ... Magnus, Slanik. 2. ... 86-07 ... 13-95 ... 100-02 ... Malagutti, Do. (m. of 3). 3. ... 86-80 ... 14-06 ... 100-86 ... Johnston, Urpeth. 499. HATCHETINE, Conybeare. Mineral tallow. Occurs flaky, like spermaceti ; or sub-granular, like bees' wax. Soft and flexible. G. = 0'6 (when fused, 0-983). Translucent ; lustre weak pearly ; colour yellowish-white, wax-yellow, or greenish-yel- low ; feels greasy ; inodorous ; readily soluble in ether. Chem. com. of a variety from Glamorganshire, 85-91 carbon and 14'62 hydrogen, or similar to ozokerite. This variety is fusible at 115, and another from Loch Fyne near Inverary at about the same point. Another, forming small veins in the ironstone of Merthyr-T} r dvil, only melts at 170. It is thus probable that various substances have been included under this name. A mineral, similar to that from Merthyr-Tydvil, has been found by Dunker in clay ironstone from the lower wealden near Sooldorf in Schaumburg. 500. FICHTELITE, Bromeis. Occurs in crystalline lamellae, which swim in water, but sink in alcohol. They are white and pearly, and fuse at 115, but again be- come crystalline on cooling. Very easily soluble in ether, and preci- pitated by alcohol. Chem. com. C 4 H 3 , Bromeis found 89-3 carbon and 10'7 hydrogen. It occurs between the annual layers of wood in pine trees in a peat moss near Redwitz in Bavaria. 501. HARTITE, Haidinger. Resembles spermaceti or white wax, and shows a lamellar struc- ture, and probably monoclinohedric crystallization. Sectile, but not flexible. H. = 1 ; G. = 1-046. Translucent ; lustre dull resinous ; colour white. It melts at 165, and burns with much smoke. Very soluble in ether, much less so in alcohol. Chem. com. C 6 H 5 ; or, by Schrotter's analysis, 87*50 carbon and 12'10 hydrogen. Found in Family.'] KONLITE SCHEERERITE IDRIALITE. 523 fissures and cavities of bituminous and siliceous wood in the brown coal of Oberhart near Gloggnitz in Austria. 502. KONLITE, Schrotter. Occurs in small crystalline folise and grains. Soft. G. = 0*88. Translucent ; lustre resinous ; colour white ; without smell. Fuses at 126 137 Fahr. Soluble in nitric acid, and precipitated by water in a white crystalline mass. Chem. com. C 2 H, with 92*31 carbon and 7'69 hydrogen. Kraus found in that from bituminous wood at Uz- nachnear St Gallen in Switzerland, 92-49 carbon and 7'42 hydrogen ; and Trommsdorff, in that from Redwitz in Bavaria, 92-43 carbon and 7 '57 hydrogen. 503. SCHEERERITE, Stromeyer, Phillips^ Mohs. Monoclinohedric, in tabular or acicular crystals. Soft and rather brittle. G. = 1/0 1/2. More or less translucent ; lustre resinous or adamantine ; colour white, inclining to yellow or green. It feels greasy, has no taste, and when cold no smell, but when heated a weak aromatic odour. It fuses at 111 to a colourless fluid, which crystallizes again when cold ; and, at 198, can be distilled over with- out decomposition. Insoluble in water ; but readily in alcohol, ether, nitric and sulphuric acid. Chem. com. CH 2 , with 75 carbon and 25 hydrogen, which nearly agrees with an analysis by Macaire-Prinsep. Occurs in the wood of the brown coal at Uznach with kon lite, with which it is occasionally confused. The following are similar com- pounds ; Branchite of Savi, from the brown coal of Monte Vaso in Tuscany, fuses at 167, and is white, translucent, and feels greasy ; Tekoretine, fusible at 113, soluble in ether, but difficultly in alcohol ; and PhyUoretine, more soluble in alcohol, and fusible at 188. The last two were found by Forchhammer in fossil pine trees in Denmark. 504. IDRIALITE, Schrotter ; Idrialine, Dana, Dufrenoy. Massive; fracture uneven or slaty. Sectile. H. = 1/0 1*5; G. = 1/4 1/6. Opaque ; lustre resinous ; colour greyish or brown- ish-black; streak blackish-brown, inclining to red. Feels greasy. It burns with a thick smoky flame, giving out sulphurous acid, and leaving some reddish-brown ashes. Chem. com. according to Schrot- ter, idrialine and cinnabar, mixed with a little silica, alumina, pyrite, and lime. The idrialine may be extracted by warm olive oil or oil of turpentine, and then appears as a pearly shining mass. Dumas gives its composition as C 3 H, with 94*75 carbon and 5*25 hydrogen. Bodeker says this is the composition of Idryl, a new substance produced from idrialine, and finds in the latter, as the mean of four analyses, 524 MELLITE OXALITE. [Inflammable Sails agreeing very closely, 91/83 carbon, 5-30 hydrogen, and 2-87 oxygen. In one specimen of idrialite, with G. = 1-721, Schrotter found 77*32 idrialine, 37*85 cinnabar, and 2 -75 other substances ; in another spe- cimen, G. =3-231, 31-56 idrialine, 68-34 cinnabar, and 1-57 other substances. It has only been found at Idria in Carniolia, in thin layers among the slates containing the mercury ores. Its inflamma- bility renders it dangerous, as the mines, when on fire in 1803, pro- bably from spontaneous combustion, were only extinguished by being laid under water. V. FAMILY. INFLAMMABLE SALTS. 505. MELLITE, Hauy, Phillips ; Honey Stone, Jameson ; Honig- stein, Werner ; Pyramidal Melichrone-resin, Mohs. Tetragonal ; P 93 1' (Breithaupt, 93 6' Kupffer}. The funda- mental form appears either alone or in combination with OP, or also with Poo and ooPoo . The crystals are usually imbedded singly, rarely conjoined in small groups or druses. It also occurs massive and granular. Cleavage, pyramidal along P very imperfect ; in ge- neral only the conchoidal fracture is seen. Rather brittle. H. = 2-0 2-5; G. = 1-4 1-6. Transparent to translucent; distinct double refraction. Lustre between resinous and vitreous. Colour honey-yellow to wax-yellow, or occasionally reddish. Streak whit- ish. In the closed tube it yields water. B.B. carbonizes without any sensible odour, at length burns white, and acts like pure alumina. Easily and entirely soluble in nitric acid or solution of potash. Chem. com. ii M 3 + 18 H, with 40'53 mellic acid (M = C 4 3 ), 14-32 alu- mina, and 45*15 water. Analyses. 1 2 Mellicl Alu- acid. jmina. Water. Total. 46 I 16 41-4 1 14-5 38 44-1 100 100 Klaproth, Artern, Wohler, Do. Wohler also found traces of iron and a resinous substance. This is a rare mineral, occurring chiefly at Artern in Thuringia in brown coal ; also in brown coal at Lauschitz near Bilin in Bohemia. Glocker has found in the coal of the greensand at Walchow in Moravia yel- low and white mellite, differing from the common variety in contain- ing more alumina, less water and mellic acid, and a small proportion of silica. Family.] OXALITE. 525 506. OXALITE, Hausmann ; Humboldtine, de Rivero, Mohs ; Oxalate of Iron, Phillips ; Fer oxalate, Hauy. Occurs in capillary crystals, but system not known ; and also bo- tryoidal or in plates, partiy fine granular, partly fibrous, or compact. Fracture uneven or earthy. Slightly sectile. H. = 2 ; G. = 2*15 2-25. Opaque; lustre weak resinous or dull. Colour ochre or straw-yellow. B.B. on charcoal becomes first black then red ; and with borax or salt of phosphorus shows reaction for iron. Easily so- luble in acids. Solution of potash separates the protoxide of iron, which is first green and then reddish-brown. Chem. com. 2 Fe c" + 3 H, with 42*7 oxalic acid, 41*4 iron protoxide, and 15*9 water. Mariano de Rivero found in a specimen from Kolosomk 46*14 oxalic acid and 53*86 iron protoxide, but the analysis seems incorrect. Rammelsberg obtained 42*40 oxalic acid, 41*13 iron protoxide, and 16*47 water ; and, in two subsequent trials, 40*24, and 40*8 per cent, of iron protoxide from the same variety. He thinks that the mine- ral examined by Thomson, who doubts the presence of oxalic acid, was the yellow iron ore (p. 327), with which this species is sometimes confused. It occurs in the brown coal at Kolosoruk near Bilin in Bohemia, and also at Gross Almerode in Hessia. Brooke observed some minute crystals of Oxalate of Lime on a spe- cimen of calcspar from an unknown locality.* * The Struvite of Ulex, though not properly belonging to the mineral kingdom, may be here noticed. It occurs in rhombic crystals, P 104 Q 10', 92 18-, and 135 39' (Marx), with one perfect cleavage. H. = 1 5 2 ; G. = 1 '66 1 75. Transparent or opaque ; lustre vi - treous ; colourless, but coloured yellow or brown. In the closed tube yields water and am- monia. B.B. fuses to a white enamel. Soluble in hydrochloric acid; and very slightly in water. Chem. com. probably like that of the artificial phosphate of ammonia and magnesia, in which Otto found 28-12 phosphoric acid, 16-28 magnesia, 6'83 ammonia, and 48'77 water, but mixed with protoxide of iron, from a mere trace to 10 per cent. This substance was found in peat earth covered with stable refuse in digging the foundation of the St Nicolai Church at Hamburg in 1845, and since in other places near putrescent animal matter, and in guano from Africa. The crystals seem very liable to decomposition. Their true character has occasioned much controversy in Germany. APPENDIX. MOHS and some other mineralogists have introduced air, water, and various other gaseous and fluid substances into their systems of mineralogy. Properly these are not simple minerals, and the de- scription of their nature and properties belongs to chemistry, or other branches of science. They have in consequence been omitted in the above system ; but we may here shortly describe the characters of water in its two conditions of solid and fluid. WATER ; Wasser, Hausmann ; Eau, Beudant. Fluid and amorphous. Gr. = 1-000 when pure, but sea water as high as 1-027 and 1-0285 at 62 Fahr. When pure it is without taste or smell, and colourless in small quantities, but in larger masses green or blue. Chein. com. HO, or hydrogen-oxide, with 88-9 oxygen and 11 ! hydrogen. At 32 Fahr. it freezes and changes to ICE. Solid and hexagonal. Smithson describes the crystals as regular pyramids, with angles of 142 30' and 80 nearly : Clarke as rhombohe- drons of 120 and 60. It usually appears in six-sided tables, either of OP . GoP or OR . b 3 St 448 Wolfsbergite Cu Sb- 457 Bournonite Cu*Sb + 2Pb 3 Sb- 472 Miargyrite Ag s/b 471 Pyrargyrite, dark* Ag 3 Sb. 460 Stephanite Ag 6 Sb- 459 Frcieslebenite Pb Sb + 2 (Pb, Ag) 8 Sb. R. 461 Polybasite (A'g, Cti)9 Sb. 455 Fahlore (Antimony-F. )* (Fe, Zn) 4 Sb + 2 (cfu, Ag) 4 Sb. 1 From the isomorphism of the two sulphurcts properly belongs to 1. * The minerals marked with a star (), in consequence of the isomorphism of their components, occur in several parts of the system. 532 CHEMICAL ARRANGEMENT 455 White Fahlore ......... (Fe, ^n, Cu)*Sb + (Pb, Ag)*gb. 404 Mispickel .................. ) -' e + Fe As> 404 (Plinian. Brthpt.) ...) 403 Leucopyrite ...... , ........ M + Ki As, or M (S, As). 410 Amoibite .................. Ni* (S 3 , As*). 405 Cobaltine .................. Co + Co As, or Co (S, As). 406 Smaltine ................. (Fe, Co) + (Fe, Co) As, or (Co, Fe) (S, As). 447 Gotthardtite ....... ..... Pb 2 , As. 456 Copper blende ......... (Cu, Zn, Fe) 4 As. 456 Tennantite ............... (Fe, Cu)* As + 2 Cu* As. 455 Fahlore (Arsenic F.)* (Fe, Zn)* As + 2 Cu* As. 471 Pyrargyrite, pale* ...... Ag 3 As. // 473 Xanthokon ............... Ag 3 As + 2 Ag 3 As. / III HI 444 Geokronite* ............ Pb 5 (Sb, As). 443 Boulangerite ........ .... Pb, Sb, As, S. 458 Wolchite .................. Pb, Cu, Sb, As, S. 455 Fahlore (Antimony-Ar- senio.Fahlore)* ...... R 4 (Sb, As) + 2 Cu* (Sb, As). 3. Combinations of Sulphurets and Tellnrets. 437 Tetradymite. a) From Schemnitz ... ]Bi + 2BiTe s . D. Oxides. 91 Brucite (Hydrate of Mag- nesia) ........................ 163 Corundum ..................... A1 - 155 Diaspore ........................ A1H- 156 Hydrargyllite .................. AH 3 . 161 Spinel ........................... MgAi OF MINERALS. 533 Volknerite. Herm Mg 6 Al + 15 H. 164 Chrysoberyl BeA'i 354aPechurane :~. UU. 371 Uranuin-ochre tJJ H. 859 Hausmannite MnMn. 360 Braunite Mn. 358 Manganite MnH. 357 Polianite > 356 Pyrolusite \ 365 GroroUite MnH. (?) 1 Mn Mn 2 + H or 3H (Mn, ulomelane 1 . . r ad partly replaced by K, Ba, Mo-. f!n. r,r^ 361 Psilomelane. 365 Wad. Mg, Cu, Co). 335 Magnetite FeFe. 338 Haematite -i Specular iron \ ^ e ' Brown iron ore. 341 a) Gotheite, &c FeH. 340 b) Limonite, &c Fe 2 H 3 . 341 c)Turgite Fe 2 H. (?) 157 Periclase Mg (Fe). 161 Pleonaste (Mg, Fe) AL 161 Chlorospinel Mg(A'iFe). 379 Zincite Zn. (?) 162 Automalite (Zn, Fe) Al. 337 Franklinite (Dysluite) (Zn, Fe, Mn) (Fe, Mn). 344 Cassiterite Sn. 373 Lead-ochre Pb. 372 Minium Pb IPb or Pb 8 Pb. 355 Plattnerite Pb. 368 Bismuth-ochre Bi. 376 Cuprite Cu. 534 CHEMICAL ARRANGEMENT 378 Tenorite Cu. 363 Cupreous Manganese (Mn, Cu) Mn 2 + 2 H. 361 Earthy Cobalt (Co, Cu) Mn 2 + 4H. 44 Quartz j ... l l Haytorite | Si ' 2 Opal Si, H. 251 Sassoline BH3. Titanic acid Ti. 353 a) Rutile. 352 b} Brookite. 354 c) Anatase. 370 Tungsten ochre W. 367 Molybdena ochre Mo. 336 Chromite (Fe, Mg) (cr, Ai). 339 Irite (lr,6s,Fe)(Ir,Os,Cr). (?) 375 Tellurite fe. 380 Valentinite Sb. 369 Antimony ochre Sb S b, H. Perhaps also "S'XH. 381 Arsenite As. E. Oxysulphurets. 420 Voltzine ZnZn 4 . 449 Kermes SbsV IV. Combinations of Elements with bases of Salts (Salzbildnern). A. Iodine compounds. 331 Coccinite Hg I. (?) 330 lodite Ag I. B. Bromine compounds. 332 Bromite AgBr. OP MINERALS. 536 C. Chlorine compounds. 233 Rock salt Na d. 256 Sal-ammoniac -,- NH* Oi. 316 Cotnnnite Pb Oi. 815 Mendipite PbCl + 2Pb. 295 Atacamite (CuCl -f- 3 Cu) + 3 H and 6 H. 329 Calomel HgCl. 328 Kerate AgOi. D. Fluorine compounds. 205 Fluor spar Ca PI. -(209 Cryolite 3 Na Fi + Ai Pi. '210 Chiolite . 3 IsTa FI+ 2 Ai Fl 3 . Herm. or 2]STaPl + AlPl3. Chodn. 206 Yttracerite Ca Pi, Ce Pi, Y PL - 207 Fluocerite. 207 a) neutral Ce PI, Ce Fl 3 . 208 b) basic (Fluocerine) Ce Fl 3 +3 Ce H. V. Combinations of electro-positive Oxides (Bases} with electro- negative Oxides (Acids). Oxygen salts. I. Siliceous- acid Salts (Silicates). 1. Silicates of Lime. 58 Okenite Ca 3 Si' 4 + 6H Trisilicate of Lime from Gjelleback Ca'Si. 108 Wollastouite Ca 3 Si' 2 . 2. Silicates of Lime and Alkali. 59 Pectolite [3 (Na, K) Si + 4 Ca 3 Si 2 ] + 3H. 3. Silicates of Magnesia. 76 Steatite Mg'Si. Berzelius. Lychnell. Or 6 Mg'Si + 4 Mg 3 Si' 2 . R. 536 CHEMICAL ARRANGEMENT 76 Talk 3MgSi + Mg 3 Si 2 . R. 140 Meerschaum ... Mg*Si + H, or 2 H. 140 Aphrodite Mg 3 *Si 2 + 2H = (2MgSi + H) + MgH. 84 Gymnite Mg 2 Si' + 3 H = (Mg Si + 2 H) + MgH. 83 Spadaite Mg 5 Si*+4H = (4MgSi+3H) + MgH. 81 Picrosmine 2Mg 3 Si 2 +3H=(4MgSi+H)+2MgH. 136 Kerolite Mg, Si", H. (S. also 19. Alumina-Magnesia-Silicates.) 4. Silicates of Magnesia and Alkali. 143 Retinalite (2 NaSi + Mg 3 Si) + 8H. 5. Silicates of Magnesia and Lime. klOl Augite Ca 3 Si' 2 + Mg 3 Si' 2 . Comp. 30, 31, 32, (Diopside, Malacolite.) 40, 46. 100 Hornblende Ca Si + Mg 3 Si 2 , perhaps also 3 RSi (Tremolite, Gram- + 2 R 3 Si* 2 . Comp. 29, 31, 33, 40. matite, Actino- lite, Asbestus in part.) 29 Nephrite Ca, Mg, Si'. 6. SUicate of Glucina. 170 Phenakite Be 3 Si 7. Silicates of Alumina, 137 Agalmatolite* *Al'si 3 . Lychnell. Comp. 8. 96 Pyrophyllite* A! Si' 3 + 3 H (?> R. Comp. 19. 141 Razoumoffskin ... Al*Si 2 +3H 151 Xenolite AISL 98 Pholerite AlSi + 2H. 152 Bamlite *Al 2 Si 3 . 153 Andalusite Ai 4 Si 3 . (Bucholzite, Fibro- lite.) OP MINERALS. 587 150 Cyanite 151 (Sillimanite.) 151 Worthite ^ Al 6 Si' 5 + 3 H = 5 Al Si + A1H 3 . 128 Allophane Al 3 Si 2 + 15 H and 20 H. 129 Opaline- Allophane (Ai* Si + 12 H) -f 2 Al H 3 . 120 Kaolin. a) common Al 3 Si 4 -f 6 H, Forchhammer, or Al Si + 2 H, mixed with Si*. Brongn. Malaguti. b) from Passau A'i 3 Si 3 + 6 H. 131 Bole, in part 139 Catlinite 137 Cimolite 133 CoUyrite 126 Halloysite \- Ai, Si', H- 126 Lenzinite 178 Nontronite 134 Lithomarge 126 Tuesite 8. Silicates of Alumina and Potash. 3 Potash-Felspar ... KSi + AlSi' 3 . (Orthoclase.) ,- ; 39 Leucite K*Si 2 + 3 Ai'Si 2 . 50 Damourite (K Si + 3 Al Si') + 2 H = (K Si + AlSi 3 ) + 2A1H. 137 Agalmatolite* Ai, K (Ca), Si',H. Comp. 7. 9. Silicates of Alumina and Soda. 5 Soda-Felspar Na Si + Ai Si 3 . (Albite.) <|' 48 Mesotype (Na Si + Ai Si) + 2 H. (NatroUte.) 538 CHEMICAL ARRANGEMENT 49 Lehuntite (Na Si + AI Si") + 3 H. 47 Analcime (Na 8 Si 2 + 3 A! Si 2 ) + 6 H. 10. Silicates of Alumina, Soda, and Potash. 5 Potash- Soda -Fel- 1 spar, (Periclinei ( K, ^a) Si + Ai Si 3 and in part, Albite in > . . part.) I (Na,K)Si+AlSi3. 3 Glassy Felspar ...J 4 Ryacolite (Na, K) Si + A'i Si. 23 Nepheline (Elseo- (Na, K) 2 Si + 2 Ai Si. lite) 15 Pollux. Brthpt. K, Na, Sij H. 11. Silicates of Alumina and Lithia. 14 Kastor. Brthpt. Li Si 3 + 2 A'i Si' 8 . A. Zygadite. Br. ... Li, A1,SL 12. Silicates of Alumina, Lithia and Soda. 12 Petalite (Li, Na) 3 Si 4 + 4 A'i Si 4 . 13 Spodumene (Li, Na) 3 Si 4 4- 4 Al Si' 2 . 13. Silicates of Alumina and Baryta. 62 Harmotome (Ba 3 Si' 2 + 4 Ai Si 2 ) + 18 H. v. Kob. 14. Silicates of Alumina, Baryta and Strontia. 55 Brewsterite [ (Sr, Ba) Si + Ai Si 3 ] + 5 H. 15. Silicates of Alumina and Lime. 54 Beaumontite (R Si' 2 + Ai Si' 3 ) + 5 H. 53 Aedelforsite (Ca *Si + AI Si 3 ) + 4 H. 52 Stilbite (Ca Si" + Ai Si 3 ) + 6 H. OF MINERALS. 539 54 Heulandite (3 Ca Si + 4 A'i Si' 3 ) + 18 H or 21 H. 66 Leonhardite ... (3 Ca Si + 4 Ai Si 2 ) + 15 H. 60 Phacolite {2 Ca Si + A'i 2 Si' 3 ) + 10 H 49 Scolezite (Ca Si + Al Si) + 3 H. 49 Caporcianite ... (Ca Si + A'i Si) + 3 H (?). (3 Ca Si + I x>i c: _i_ o AI c;\ j_ TT J v IV/a 1 T* Z A* fcl ) + D " 49 Poonalilite < 5 Ai Si')] : r r I +12H= (. J 80 Chabazite (Ca 3 Si' 2 + 3 A'i Si 2 ) + 18 H and (Ca Si + Ai Si 2 ) + 6 H. 65 Laumontite (Ca 3 Si 2 + 4A1 Si 2 ) -f 18 H, or perhaps (Ca 3 Si 2 + 3 Al SP) -f 12 H. 19 Barsowite Ca 8 Si 2 + 3 A'i Si. 67 Glottalite (Ca 3 Si 2 + Al Si) + 9H. 17 Meionite a 3 Si + 2 Ai si 17 Weraerite Ca 3 Si + 3 Ai Si*. 10 Anorthite Ca 3 Si' + 3 Ai Si. 84 Zeagonite (3 R Si + 4 Al Si) + 15 H. (Gismondine) B. Alumocalcite ...~\ 68 Edingtonite I ^- -.- . 52 Sphajrostilbite... f 52 Hypostilbite ...J 16. Silicates of Alumina, Lime, and Potash. 49 Antrimolite (3 R Si + 5 A'i Si) + 15 H. .Perhaps (R Si + 2 A'i Si) + 5 H. R. (99) Polyargite (R 3 Si 2 + 5 Al Si) + 4 H. 17. Silicates of Alumina, Lime, and Soda. 61 Faujasite (R 8 Si' 4 + 3 Ai Si' 2 ) -f 24 H. 56 Epistilbite (R Si + 3 Al Si 3 ) + 5H. 540 CHEMICAL ARRANGEMENT Oligoclase ...... \ (Hafnefjordite, C R Si' + Al Si' 2 . Loxoclase) ) 8 Labradorite ... R Si + A'i Si. 49 Mesolite. b) Li (Harrington- ite?) 40 Porcelain-Spar (Na Si + A'i Si. > (Ca 3 Si 2 + 2 Al Si'.) 6 Audesin ......... R 3 Si 2 + 3 A'l'Si 2 . 7 Saccharite ...... 2 (B 3 Si' 2 + 3 A*i Si 2 ) + 3 H. 60 Lederite ......... (R 3 Si 2 + 3 Al Si 2 ) + 6 H. 60 Gmelinite ...... (R 3 Si 2 + 3 Al Si' 2 ) + 18 H. 17 Scapolite ......... R 3 Si 2 + 2 A'i Si. 49 Brevicite ......... (R 3 Si' 2 + 3 A'i Si) + 6 H. 49 Mesole ............ (R 3 Si 2 + 3 Al Si) + 8 H. ? 47 Sarcolite ......... R 3 Si + A'i SL 10 Indianite ......... R 3 Si + 3 Al Si. 51 Thomsonite ...... > ...... 51 Comptonite ...... } ( R3 Si + 3 Al hi) + 7 H. 18. Silicates of Alumina, Lime, Soda, and Potash. 63 Phillipsite ...... (R 3 Si 2 ' + 3 A'i Si 2 ) + 15 H. R. 19. Silicates of Alumina and Magnesia. 138 Soapstone ...... a) (2 Mg 3 Si' 2 + A'i Si) + 6 H and 10 H. ,, ((3 Mg 3 Si + 2 Al Si) + 3 H. (Sapomte) ...6) -T (4[(Mg 3 Si 2 ) + 3HJ. PyrophyUite* ... (Mg 3 Si 2 + 9 A'i Si 2 ) + 9 H. ? Comp. 7. X96 OF MINERALS. 641 87 Kammererite ... (2 Mg 3 Si" + Al Si) + 6 H*. 86 (Pyrosklerite.) Steatite from Ural j^Mg 3 Si Al 2 Si) + 3 Mg H*. Herm. C . Perthite Al, Mg, s'i. 136 Kerolite Ai, Mg, Si H. Comp. 3. 20. Silicates of Alumina, Magnesia, and Potash. 28e Onkosin Al, Mg, K, Si, H. 21. Silicates of Alumina, Magnesia, and Lime. 28d Neurolite (R 3 Si* + 5 Al si*) + 6 H. (?) 10 Amphodelite ... R 3 Si + 3 Al Si. 85 Chonikrite (3 R 3 Si + 2 Al Si) + 6 H (?), or per- haps (R 3 S'i 2 + R Al) + 3 H. (?) 113 Pyrallolite Mg, Ca,(Al) Si, H. 22. Silicates of Alumina, Magnesia, Lime, and Alkali 99 Rosellan (R 3 Si 2 + 6 Al Si) + 6 H. 26 HumboldtUite. . . 2 R 3 Si + Al Si- (Melilite.) 38 Diploite R 3 Si-+ 4 Al's'i. (?) 23. Silicates of Alumina and Glucina. 169 Beryl. Be 3 Si 2 + Al Si 2 . 168 Euclase 2 Be 3 Si + Ai 2 Si*. 24. Silicates of Zirconia. 159 Zircon., Zr Si'. 160 Malakon Zr a Si or Zr Si + H. (?) 25. Silicate of Thoria. 182 Thorite Principally = Th 3 Si + 3 H. 54.2 CHEMICAL ARRANGEMENT 26. Silicates of Mangancse-proto(per)oxide [oxydul(oxyd}]. 106 Tephroite Mn 3 Si. 360 Heterocline Mn 3 Si, mixed with Mn or Mn. 105 Manganese-sili- cate, black... Mn 8 Si + 3H. (?) 360 Marceline Mn 3 Si. 105 Silicate of Man- ganese Mn, Si. 27. Silicate of Manganese -protoxide and Lime. 105 Manganese-silir cate, red ...... R 3 Si' 2 . Comp. 46. (Bustamite.) 28. Silicates of Iron-protoxide (and peroxide.) 181 Chloropliseite ... Fe *Si + 6 H. Anhydrous Sili- cate of Iron. Thorns Fe 3 Si. 39 Sideroschisolite Fe 6 Si + 2 H. (?) 177 Anthosiderite ... Fe Si* 3 + H. 1 79 Pinguite (Fe Si + Fe 2 ' Si 3 ) + 15 H. D. Thuringite (8 Fe 3 Si' + Fe 2 Si) + 12 H. 176 Hisingerite (Fe Si* + Fe Si) + 6 H (?), O r perhaps (Thraulite.) Fe Si + 3 H. (?) 29. Silicates of Iron-proto(per)oxide and Soda. 112 Krokydolite ... (STa 3 Si 4 + 3 Fe 3 Si 2 ) + x H. 100 Arfvedsonite*... Na Si + Fe 3 Si 2 . Comp. 5, 31, 33, 40. 110 Achmite Na Si + Fe Si 2 . 30. Silicates of Iron-proto(per)oxide and Lime. 116 Babingtonite ... 2 Ca Si + Fe 3 Si* 2 . OF MINERALS. 543 101 Augite* Ca*Si + Fe s Si 2 l Comp. 5, 31, 32, 40, 46. (Black A. from Arendal, He- denbergitefrom Tunaberg.) 1 75 Wehrlite (Fe, Ca) 3 Si + 3 Fe Si. 175 Lievrite 3 (Ca, Fe) 3 Si + Fe 2 Si. 31. Silicates of Iron-proto(per)oxide and Magnesia. 100 Hornblende* ... Fe Si + Mg 3 Si* 2 . Comp. 5, 29, 33, 40. (Anthophyllite, Asbestus in part.) 103 Bronzite* ....... ^ ^ ^ 3Q 81 Pycrophyll K, 3 Si 2 + 2 H. 142 Dermatine E, 3 Si 2 + 6 H. (?) 81 Monradite 4 R 3 Si 2 + 3 H. 79 Hydrophite R 2 Si + 3 H. (?) )fl73 Olivine (Mg, Fe) 8 SL (Hyalosiderite.) 82 Villarsite 4 R 3 Si + 3 H. 77 Schilierspar (3 R Si + 2 H) + 2 Mg H. R. 78 Antigorite R 3 Si 2 + Mg H. 80 Chrysotile (K 3 'Si 2 + 2 H) + Mg H. ( Baltimorite , Schweitzer's Talksilicate.) 80 Serpentine (2 R 3 Si 2 + 3 H) + 3 Mg H. Magnesia-silicate (from Zer- matt) 2 (R 3 Si* + 3 H) + 3 Mg H. 544 CHEMICAL ARRANGEMENT 93 Nemalite (R 3 Si + 6 H) + 6 Mg H. 100 Rock-wood (from Sterzing) ... 3 (Mg'si + H) + (p'4 Si 2 + 2 H). 32. Silicates of Iron-proto(per)oxide, Magnesia, and Lime. 101 Augite(Diopside, R 3 Si 2 , or more precisely partly Sahlite, Mala- (Ca, Fe) 3 Si 2 + Mg 3 *Si 2 , partly colite, Dial- Ca 3 Si 2 + (Mg, Fe) 3 Si 2 . Comp. 5, lage, Hyper- 30,31,40,46. sthene,Asbes- tusin part)... 173 Batrachite R 3 Si. 100 Xylite (R Si + Fe Si) + H. 33. Silicates of Iron-protoxide, Magnesia, Lime, and Alkali. 100 Aegirine* (Na, K, Ca, Mg) Si + Fe 3 Si 2 . Comp. (Arfvedsonite.) Hornblende, 5, 29, 31, 40. 34. Silicates of Iron-proto(per)oxide and Alumina. 131 Rhodalite (=sBole) (F*e, A*l) 'si* 4 + 9 H. (?) 154 Staurolite. a)Fr.StGott- hardt R 2 Si.' b) Fr. Airolo R 3 Si 2 . c)Fr. Brittany and Ural... R^ Si' 4 . 123 Erinite 1 (Ai, Fe) Si 2 + 6 H. 132 Teratolite (Fe, A'i) 2 si 3 + 6 H. (?) 90 Stilpnomelan ... (2 Fe 3 Si 2 + Al Si 2 ) + 6 H. 144 Garnet* (Alman- Fe' 3 Si + Af SL Comp. 86, 38, 40, 47, dine) 49,50,51. XI. 73 Chloritoid* Fe 8 Si* + Ai 3 Si. Erdm. Comp. 38. 1 An Arseniate of Copper has the same name. OP MINERALS. 545 73 Sismondine Fe (Fe), Al, Si', H. 122 Kock-soap 1 181 Bole in part I Thesame . -r, IChamoisite | H(. -s (Malthazite J 35. Silicates of Iron-proto(per)oxide, Alumina, and Alkali. 47 Cluthalite (R 3 Si 2 + 3 A! Si 2 ) + 9 H. (?) 72 Lepidomelan ... (Fe, K) s Si" + 3 (Fe, Al) Si. F. Iberite [ (Fe, &) 3 Si + 3 Al'si] + 3 H. 121e Finite in part * Al, Fe (Fe ?) K, Si, H- Comp. 39. (From Stolpen, Pennig.) 36. Silicates of Iron-proto(per)oxide, Alumina, and Lime. 117 Isopyr 2 (Ca, Fe) Si + Al Si' 2 . R. (?) Ca Si + (Al, Fe) Si. ron Kob. (?) 28 Huronite (R 3 Si 2 + 4 Ai Si) + 3 H. 27 Prehnite (Ca 2 Si + R Si) + H. 28 Kirwanite (3 R 2 Si* + Al Si) -H 2 H. G. Diphanite (2 R 2 Si + 3 Al 3 Si) + 4 H. 144 Garnet* ......... R 8 Si + Al Si). Comp. 34, 38, 40, 47, (Essonite, Gros- 49, 50, 51. XI. sulaire, Ka- neelstein, Ro- manzowite.) 148 Epidote* R 3 Si + 2 R SiV Comp. 50. (Epidote and Pistacite.) 148 ThuHte R 3 Si + 2AisL 28 Zeuxite (R 3 Si + 2 R i'i) + 2 H. (?) 25 Gehlenite 2 Ca 3 Si +R 2 *Si. zz 546 CHEMICAL ARRANGEMENT Scorilite Ca, Ai, Fe, si*. 123 Plinthitc Ca, Ai, Fe, Si, H. 37. Silicates of Iron-proto(per)oxide, Alumina, Lime, and Alkali. 130 Chalilite (3 R Si + 4 R Si) 4- 12 H. (?) 19 Bytownite ...... (Ca, Na) 3 Si' 2 + 3 (Ai, Fe)'si. 18 Nuttalite 3 R 2 Si + 2 AI Si. 8 Saussurite Na, Ca, Fe, Al, Si. 38. Silicates of Tron-proto(per)oxide, Alumina, and Magnesia. 114 Pyrargillite ( R Si + Al Si) + 4 H. 171 Cordierite R 3 Si 2 + 3 R M. ( Steinheilite, hard Fah- lunite.) 171a Bonsdorffite ... (R 3 'si 2 H- 3 R si) + 2 H. (Metam. Cor- dierite.) 1716 Esmarkite (R 8 Si 2 + 3 AI Si) + 3 H. (Metam. Cor- dierite.) 171c Fahlunite (R 3 Si 2 + 3 R Si) + 6 &. (Metam. Cor- dierite.) 144 Garnet R 3 Si + AJ'si. Comp. 34, 36, 40, 47, (From Ohla- 49, 50, 51. XI. pian, Hal- landsas, etc. 171# Praseolite (R 3 Si + 2 Al* Si) + 3 H. (Metam. Cor- dierite.) 86 Pyrosklerite ... (2 R 3 Si + Al si) + 4-|- H. (?) 73 Chloritoid.*Bons- dorflf (3 R 3 Si + 2 A13 ^ + g H. Comp. 34. OF MINERALS. 547 75 Chlorite (Pen- nine, Leuch- tenbergite)... (Mg 3 Si' 2 + 3 R Si) + 9 Mg H. R. 74 Ripidolite ~ (R 3 Si + 8 R Si) + 9 ]ftg H. R. 161 Saphirine 3 R Al + Al Si. (?) 158 Boltonite Gedrite (= Hy- persthene) 171 Aspasiolite "1 (Metam. Cor- dierite.) f- Mg, Fe, (Fe), Al, Si, H- 76 Steatite* j 96 Vermiculite J 39. Silicates of Iron-proto(per)oxide, Alumina, Magnesia, and Alkali. [y- ( Mg, Fe, Al, Si. 71 Mica, mono-ax- (Fe, Mg, K) 3 Si + (Fe, Al) Si. ial* Comp. 57. I71e Finite in part* (Fe, Mg, K) Si + Ai Si. Comp. 35. ( From Au- vergne.) 171/Gigantolite (R Si + Al' Si) + H, (Metam. Cor- dierite.) 171 Weissite R 3 Si' 2 + 2 Al Si' 2 . (Metam. Cor- dierite. ) 124 Greenearth Fe, Mg, K, Al, Si', H. (Inpt. metam. Augite.) 548 CHEMICAL ARRANGEMENT 40. Silicates of Iron-proto(per)oxide, Alumina, Magnesia and Lime. 101 Aluminous Au- gite* R 3 (Si;Ai) 2 . (?) (Diallage,Hy- persthenein pt. Comp. 31, 32.) 101 Aluminous Horn- blendes R (Si, A'i) + R 3 (Si, Al)2. (?) 94 Seybertite (R Si + R 3 Al 2 ) + H. (?) ObXan- thophyllite ? 94 Xanthophyllite [3 (R *Si* + R 3 Al 2 ) + H] + A'i HS. (?) 144 Garnet* R 3 Si + R Si. Comp. 34, 36, 38, 47, 49, 50, 51, XI. 147 Vesuvian Same Formula. ( Frugardite, R usually = Ca, Fe, sometimes also Mg, Gokumite.) Mn, and Na. R = Al. 148 Puschkinite R 3 Si + 2 R Si. (Magnesia-Epi- dote.) 101 Jeffersonite, * Thomson 3 R 3 Si 2 + Al 2 gi. (?) Comp. 47. 41. Silicates of Iron-proto(per)oxide, Alumina, Magnesia, Lime and Alkali. a) Containing Potash. 100 Raphilite 6 (Ca, Mg, K) Si + R Si. (?) '"119 Tachylite R 3 M 2 + Al Si. 6) Containing Soda. 158 Wychtine R 3 Si 2 + R SiX 158 Glaucophane ... 3 R 3 *Si 2 -f 2 A'i Si 2 . 42. Silicates of Iron and Cerium-protoxide (La, Di). 187 Cerite (Ce. La, Di, Fe) 3 si + 3 H. OP MINERALS. 549 43. Silicates of Iron and Cerium protoxides, Yttria (and Glucina.) 184 Gadolinite OR 3 Si! (?) 44. Silicates of Iron protoxide, Cerium protoxide, Alumina and Lime. 185 Allanite ' 3 R 3 Si -I- 2 A'i Si. 185 Cerine 3 R 3 Si + 2 R Si. 45. Silicates of the former and of Yttria. 185 Orthite 3 R 3 Si" + 2 Al Si. 185 Pyrorthite Orthite mixed with silicates of Ce, Y, Mn, Fe, AL 46. Silicates of Iron and Manganese proto(per)oxides. 105 Thomson's Si- licate of Man- ganese from Franklin ... 105 Red Silicate of R 3 Si' 2 . Comp. 27. from Algiers 107 Troostite Fe 3 Si 2 + 3 Mn 3 Si. 173 KnebeUte Fe 3 Si + Mn 3 Si. Siliceous-sinter from Freiberg (Fe, ivtn)3 *Si2 + 18 H. 173 Fowlerite Mn, Fe (Fe ?), Si, H. 47. Silicates of Iron proto(per)oxide, Manganese protoxide and Lime. 101 JeflFersonite,* Keating R Si. (?) Comp. 40. 550 CHEMICAL ARRANGEMENT 144. Garnet* (Ca, Mn) 8 Si + Fe'Si. Comp.34, 36, (From Lindbo, 38, 40, 49, 50, 51, XI. Langbans- hyttan, Al- I tenau, Suhl, etc.) 48. Silicates of Iron and Manganese proto(per)oxides 82 Villarsite 4 R 3 Si + 3 H. 89 Cronstedtite ... (Fe, Mn, Mg) 3 Si + FB H 3 . 49. Silicates of Iron and Manganese proto(per)oxides and Alumina. 20 Ottrelite (R 3 Si 2 + 2 Al Si) + 3 H. 144 Garnet* R 3 Si + AlSi*. Comp.34, 36,38, 40, (From Fahlun, 47, 50, 51, XI. Hungary, Eng- so, Franklin, Broddbo.) 115 Karpholite (R 3 Si + 3 Al Si) + 6 H. (?) 50. Silicates of Iron and Manganese proto(per)oxides, Alumina and Lime. 144 Garnet* E 8 Si + HSi. Comp. 34, 36, 38, 40, (White G. from 47, 49, 51, XI. Tellemark, brown from Klemetsaune, Hesselkulla, Arendal, Franklin, Ve- suvius.) 148 Manganese-Epi- dote* R 3 Si' + 2RSi. Comp. 36. OF MINERALS. 551 118 Polylite 7 ^ ( p e ?) ^ fc - Ai & 147 Xanthite > 51. Silicates otthe above and of Magnesia. 144 Garnet* R 3 Si + R S*i. Comp. 34, 36, 38, 40, (Malsjo, Gott- 47, 49, 50, XL hardt, Wilui, Friedeberg, Arendal, Hal- o landsas.) Polyadelphite, [= Garnet] R, R, SL 52. Silicates of Nickel protoxide and Magnesia. 141 Pimelite 2 R Si + H. 53. Silicates of Zinc oxide. 269 Williamite Zn 3 Si. 268 Galmei 2 Zn 3 Si + 3 H, or Zn 3 Si + 2 H (Thomson's and Hermann's An.) 54. Silicates of Copper protoxide. 278 Dioptase Cu 3 Si 2 + 3 H. 279 Chrysocolla Cu 3 Si 2 + 6 H. 55. Silicates with Sulphurets. 146 Helvine Mn Mn + 3 (Mn, Fe, Be^ Si. (?) 56. Silicates with Chlorides. 41 Sodalite Na Cl + (Na 3 Si + 3 Al Si). 46 Eudialite Na Cl + 4 [2 (Ca, Na, Fe) 3 Si 2 + Zr Si*]. 88 Pyrosroalite ... (Fe Cl 3 + Fe H) + 4 (Fe 3 Si 2 + Mn 3 Si>). (?) 552 CHEMICAL ARRANGEMENT 57. Silicates with Fluorides. f K Si + 6 Ca Si 57 Apophyllite JKF1 + SiFls + 6(Ca + Si F13) 167 Leucophane ... 2 Na Fl + (2 Ca 3 Si 2 + 3 Be 2 Si> 70 Lithia-mica. ) Lepidolite ... (K, Li, Na) Fl + (Al,Mn) si 2 . b) Lithia-mica (K, Li, Na) Fl + (Al, Fe) Si' 2 . 71 Mica, brown bin- axial from N.York K Fl + (3 Mg 3 Si + Al Si). Mica* (1 and 2 axial). 71 a) Magnesian... K, Mg, F*e (Fe), Al, Si, Fl. 70 b) Non-magnes. K, Fe (Fe), Ai, Si,' Fl. Comp. 39. 174 Chondrodite ... Mg Fl + 2 (Mg, Fe) 3 *Si. 165 Topaz (AlFi3 + Si P18)+ 2(A1 si+ A'i 2 Si). R. 166 Pycnite (A1F1+ SiF13)+ 8 A'i Si+Al 2 Si). R. II. Carbonates. 246 Natron Na C + x H. 248 Trona Na 2 C 3 + 4 H. 221 Witherite Ba'C. 225 Strontianite ... Sr C. 204 Arragonite > ... 199 Calc-spar > " 249 Gay-Lussite ... (Na C + Ca C) + 5 H. 223 Barytocalcite ... Ba C + C a C and Ba C + 2 Ca C. (?) 202 Magnesite Mg C. 92 Hydromagnesite 3 (Mg C + H + Mg H. 200 Bitterspar (Ca, Mg) C. (Dolomite, Guhrho- fian, Miemite) OF MINERALS. 553 200 Predazzite (2 Ca C + Mg C) + H. (?) H. Yttria-spar Y, C. 265 Lanthanite * (La C + H) + 2 LaH. (?) (Carb. of cerium protox.) 261 Siderite [Fe, Mn, (Mg, Ca)] C. (Sphaerosiderite.) 203 Mesitine-spar . . . (Mg, Fe) C and (Mg, Fe, Mn, Ca) C. (Ankerite,Breun- nerite, Mag- nesite in pt.) 263 DiaUogite > . ..... 264 Manganocalcite I < Mn ' Ca ' Fe ' M ^ C ' 267 Calamine Zn C. 267 Zinc- bloom (Zn C + H) + 2 Zn H. 308 Cerussite Pb C. 199 Plumbocalcite... > .... 204 Lead-Arragonite 3 ^ Ca ' Pb ) C> 308 Zinc-lead-spar Zn C + 6 Pb C. 281 Mysorine Cu 2 C. 281 Malachite Cu 2 C + H or Cu C + Cu H. 280 Azurite Cu 3 C 2 + H or 2 Cu C -f Cu H. 282 Aurichalcitc ... (Zn 3 C + 2 H) + (Cu 2 C + H). 328 Silver-oxide, car- bonate of? ... Ag C. (?) Carbonates with chlorides. 314 Phosgenite Pb Cl + Pb C. Carbonates with Fluorides. 266 Parisite Ce, La, Di, Ca, C, Fl, O, H. Carbonates with Silicates. 24 Cancrinite Ca C + (Na 2 Si + 2 Al Si). 24 Stroganowite ... Ca C + [(Ca, Xa) 2 Si + 2 Al Si], 3 A 554 CHEMICAL ARRANGEMENT III. Oxalates. 506 Lime, oxalate of Ca C + H. (?) 506 Oxalite 2FeC + 3H. (Humboldtite.) IV. MeRitates. 505 Mellite (Al + 3 C 4 O 3 ) + 18 H, or (A'i + 3 C 4 H 2 O 4 ) + 15 H. V. Berates. 250 Borax Na B 2 + 10 H. I. Borocalcite Ca*B 2 + 6 H. Hydroborocalcite Ca, B, H. 216 Boracite Mg 3 'B 4 , or Mg B 2 + 2 Mg *B. 217 Hydroboracite (Ca 3 B 4 + Mg 3 *B 4 ) + 18 H. Borates with Silicates. 218 Datolite (3 CaB + Ca 3 Si 4 ) + 3 H. R. 3 (Ca B + Ca Si) + H 3 Si. Scheerer. 218 Botryolite (3 CaB + Ca 8 Si 4 ) + 6 H. R. 3(CaB + CaSi) +H6'sl. Scheerer. 149 Axiuite (Ca, Mg) 3 (Si, B) 2 + 2 (Ai, Pe, Jkin) (Si, B). R. 172 Tourmaline. a) Schorl R (13, C) + A'i Si 2 . R = Fe, Mg, Li, Na. b) Achroite ... 2 R (B, C) + 3 Ai 2 Si 3 - R = Na, Li, Mg, Mn. c) Rubellite... 2 R 2 B H- 3 Al 2 Si 3 . R = Na, Li, Mn, Mg. Herm. OF MINERALS. 555 VI. Combinations of Oxides of Titanium . a) Of Titanium oxide (Titanites l. X. 842 Titanitic-iron... Ti, Fe. H.Rose. From Iserweise Ti '+ Fe. - Egersttnd Ti 2 + Fe 8 . - Iserweise Ti 3 + Fe 4 . - Hmen M. TI* + Fe 5 . - Gastein ... Ti 5 + Fe*. - Arendal . . Ti + Fe 3 . - Spessart...) - Uddewalla) Ti + Fe- 6) Of Titanic acid (Titanates). 194 Perowskite Ca f i. 192 Polymignite ... Ca, Y, Ce, Zr, Fe, iin, Ti. 195 Aeschynite,Hart- Ce, Ca, Zr, Fe, Ti. Comp. Tantalate wall with Titanaten. Titanates with Silicates. 351 Sphene Ca 3 Si + Ti 3 *Si*. H. Rose. (Greenovite) 2 Ca Si + Ca Ti 3 . Berz. 190 Yttrotitanite ... [3 Ca 3 Si' 2 + (Fe, A!) Si] + Y Ti 8 . (Keilhauite.) A. Erdm. 189 Oerstedtite Ca, Mg, Zr, Ti, Si, H. K. Mosandrite La, Ce, isin, Ca, Mg, K, *Si, Ti, H. 186 Tschewkinite ... Ce, La, Di, Fe, Ca (Mg, MD, Be, Y, Al> SL,TL YJUL. Tantalates (containing Niobium and Pelopium). 350 Fergusonite Y, Ce, Zr, Ta, O. 556 CHEMICAL ARRANGEMENT 346 Columbite > ,-> . 347Tantalite J Fe, Mn, (Sn) Ta, O. 348 Yttrotantalite... Y, Ca, Fe, U, W, Ta, O. 188 Pyrochlore * (Microlite)from Na Fl + Ca, Ce, Th, Miask ...... Ta, O. Wohler. Comp. 0,H. 198 Uranotantalite U, Ta, O. Tantalates with Silicates. 191 Wohlerite ...... Na, Ca, Zr, Fe, Si, Ta, O. Tantalates with Titanates. 188 Pyrochlore,* from K, Na, Li, Ca, La, Ce, Zr, Fe, Ti, Ta, O. Miask ......... Herm. Comp. Tantalates. 198 Yttroilmenite ... Y, Fe, Ce, La, Ti, Ta, O. Herm. 849 Euxenite ......... Y, U, Ce, Ca, Ti, Ta, O, H. 195 Aeschynite,* Her- Ce, La, Y, Fe, Zr (?), Ti, Nb, O. mann ......... Comp. Titanates. 193 Polykrase ...... Ce, Y, Zr, U, Fe, Ti, Ta, O. VIII. Tungstates. 334 Scheelite ......... Ca W and (Ca, Cu) W. 345 Wolfram ......... (Fe, Mn) W. a) From Monte Video, Eh- renfrieders- dorf, Limo- ges, Neu- dorf.. ]V[nW OF MINERALS. 567 6) From Cumber- land, Chan- teloupe _ Mn W + 3 Fe W. c) From Zinn- wald 3 Mn W + 2 Fe W. 322 Scheelitine Pb W. IX. Molybdates. 321 Wulfenite Pb Mo and (Pb, Ca) Mo. 321 Mineral from Pamplona ... Chief constituent, Pb 3 Mo. Boussing. (?) X. Vanadiates, 320 Vanadinite (Pb Cl + 2 Pb) + Pb 3 V 2 . (?) 296 Volborthite Cu, V. XI, Chromium-combinations. a) Of Chromium oxide. 374 Wolchonskoite (Or, Fe, Al) 2 Si 3 + 9 H. (?) 374 Chrome-ochre... (Al, Or, Fe) 3 si* 4- 6 H. Wolff. 135 Miloschm (Al, Cr) 3 Si 2 + 9 H. 144 Uwarowite*... Ca 8 Si + (Cr, Al) Si. Comp. Garnet (Chrome-gar- under Silicates, net.) y 145 Pyrope Mg, Ca, Fe (Fe), Al, Or, SL 69 Fuchsite, Chrome-mica K, Mg, Al, Fe, Cr, SL 6) Of Chromic acid (Chromates). 324 Crocoisite Pb Cr. 325 Melanochroite ... Pb 3 Cr 2 . 326 VauqueUnite ... Cu 3 Cr 2 + 2 Pb 3 Cr 2 558 CHEMICAL ARRANGEMENT 833 Romeite 319 Bleinierite .. Mineral from Chile . 231 Haidingerite ... 230 Pharmacolite ... 230 Picropharmacolite 232 Berzeliite 299 Scorodite ......... 298 Pharmakosiderite (Beudantite.) 299 Arsenic-sinter.* a) From Nert- schinsk) ... (Amorphous Scorodite.) b) White, from Freiberg ... 297 Arseniosiderite XII. Antimoniates. Ca, Mn, Fe, Sb, Sb. Pb 3 Sb + 4 &. Hg, s'b, 's"b. XTTT. Arseniates. Ca 2 As + 4 H. (?) Ca 2 As + 6 H. (Ca, Mg)5As 2 + 12H. Ca 3 As + (Mg, Mn) 3 As. Fe As + 4 H. (Fe 3 As + Fe 3 As2) + 18 H. (?) Fe'Ai + 4 H. Fe 2 As + 12 H. Comp. Sulphates with Arseniates. [ (2 Ca 3 A'i + 3 Fe 2 As) + 12 HJ 507 Nickel-ochre 306 Eiythrine 288 Euchroite 283 Copper-mica 506 Struvite 1 Co 3 As + 8 H. (Cu 3 As + 6 H) + Cu H. [ (Cu, Fe) 3 As + 18 H] + 5 Cu XIV. Phosphates. a) Pure Phosphates. (Mg 2 , NH 4 ) P + 12 H. 1 From its origin this compound properly does not belong to the mineral kingdom. (Comp. note, p. 525,) OF MINERALS. 559 215 Xenotime Y 3 P. 156 Gibbsite ***.'+ 8 ** Herm - \61 Calaite -~ (A'i 4 PS + 9 H) + 2 A! H 3 . (?) 81 Peganite (Al 4 p 3 + 12 H) + 2 Al H 3 . Herm. 31 Fischerite (AVp' 3 + 18 H) + 2 Al H 3 . Herm. Alumina, phos- phate of, from Bourbon N H 3 T Al, p, H. 30 Lazulite (Blauspath) [2 (Mg, Fe) 3 P' + Al 4 P* 3 ] + 6 H. R. L. Cryptolite Ce/P. 197 Monazite (Ed- 1 Ce, La,Th,P. Kersten. wardsite ( (Ce, La) 3 P. Hermann. 197 Monazitoid (Ce, La) 5 p. Herm. 304 Uranite (Ca 3 P + 2 U 3 P) + 24 H. 303 Dufrenite 2Fe 2 p"+5H. 277 Delvauxite Fe* p*' + 24 H. 302 Vivianite 6 (Fe 8 P' + 8 H) + (Fesp'a 4- 8 H). R. 270 Triplite Fe 4 P + Mn 4 'p. 274 Heteposite ...... (2 Fe^ & + Mn 5 P 2 ) + 5 H. 273 Hureaulite (Fe 5 P* 2 + 3 Mn 5 P 2 ) + 30 HI 272 Triphyline Li 3 'P +^6 (Fe, Mn) 3 P. 214 Childrenite A'i, Fe, p. 292 Libethenite Cu 3 P + Cu H. 293 Tagilite (Cu 3 'P' + 2 H) + Cu H. 290 Phosphorocnalcite Cu 3 P* + 2 Cu H and Cu 3 'p' + 3 Cu H. 294 Ehlite (Cu 3 P + H) + 2 Cu H. 291 Thrombolite ... W'p'^ + GH. (?) 305 Chalcolite (Cu 3 'p + 2 U 3 P) + 24 H. b Phosphates with Fluorides. 33 Wagnerite MgFl + Mg 3 p. R. 560 CHEMICAL ARRANGEMENT 32 Wavellite A1F1 3 + 3 [(Al* P)+ 18 H]. Berz. (Al Fl 3 + 2 Al) -|- 6 [(Al* *P 3 ) 4- 18 H]. Herm. 34 Amblygonite ... (RF14-AlFl 3 )4-(R 5 P 3 4-Ai 5 P 3 ). R 271 Zwieselite Fe Fl + 3 (Fe, Mn)3'p. 317 Green-lead-ore* Pb Cl + 3 Pb 3 P. Comp. c, d. in part. (Pyromorphite.) c) Phosphates with Chlorides and Fluorides, 212 Apatite Ca (Cl, Fl) + 3 Ca 3 p. 212 Magnesia-apatite Ca, Mg, p', Cl, Fl, "s. 317 Green-lead-ore* (Pb, Ca) (Cl, Pi) -f- 3 (Pb, Ca) 3 K in part. Comp. , d. (PolysphaBrite.) 323 Plombgomme ... (Pb Cl + 3 Pb 3 ') + 18 Al HS. (?) d) Phosphates with Arseniates. 318 Green-lead-ore* in part. a) Mimetesite Pb Cl + 3 Pb 3 (, A*). Comp. b, c. 6) Hedyphane Pb Cl + 3 (Pb, Ca) 3 (As, p). (Hed. from Langbanshyttan.) 287 Olivenite Cu 3 (As, p) -f c u H. 289 Strahlerz Cu 3 (As, p) + 3 Cu H. (Klinoclase, A- phanese.) 284 Tirolite (Cu 8 (As, ) -{- 8 H) + 2 Cu H. (?) 285 Erinite [Cu 3 (As, p) + 9 H] + 3 Cu H. 286 Liroconite [ Cu 3 (As, P) -f 18 H + 5 Cu H] + [Al 2 (As, P) -f H]. e) Phosphates and Arseniates with Chlorides. 317 Nussierite Pb Cl 4. 5 (Pb, Ca) 3 (P, As). (?) OF MINERALS. /) Phosphates with Silicates. Ill Sordawalite Fe, Mg, Al, Si', P*; H. 183 Eulytine _ 2 Bi 2 Si 5 + Bi 2 P*. (?) XV. Nitrates. 252 Nitre K N. 253 Nitratine Na Sf. 254 Nitrocalcite Ca tf + H. 329 Mercury, nitr. of Hg, N. (?) 561 424 Clausthalite XVI. Selenites. Pb, Se. XVH. Sulphates. a) Pure Sulphates. 259 Thenardite Na S." 236 Glaubersalt NaS* + 2 H. 257 Mascagnine NH* S.* 219 Barytes Ba S." 224 Celestine SrS* Stronbarytspath\ 224 Barytocelestine > (Ba, Sr) s! 220 (Dreelite?) ...) 227 Anhydrite Ca S. 226 Gypsum Ca S' + 2 H. 229 Glauberite NaS'+ Ca*S. 260 Epsomite Mg S'+ 7 H. 228 Polyhalite [(K S*+ Mg S) + H] + (2 Ca S "4- H). 235 Altmogene A! S 3 " + 18 H. (Basic Sulphate of Alumina from Ararat.) A! S 2 j- x H. (?) 562 CHEMICAL ARRANGEMENT 30 Aluminite 35 Alumstone 234 Potash- Alum ... 234 Soda- Alum o) Neutral... 6) Basic? 234 Ammonia-Alum 234 Magnesia-Alum (Pickeringite.) 245 Uran-vitriol ... (Johannite.) 234 Manganese- Alum 234 Manganese- Magnesia-Alum 237 Melanterite 240 Coquimbite 239 Foliated Copia- pite 239 Radiated Copia- pite 239 Vitriol-ochre ... 239 Fibroferrite 239 Apatelite 234 Iron- Alum 234 Voltaite 239 Yellow iron ore a) Containing Potash... Al S + 9 H, in part mixed with Al H. (K's + 3 A1S) + 6H. (K '+ Al S 3 ) + 24 H. (Na S + Al S'3) + 24 H. (2 Na S' + 3 Al's 2 ) + 10 H. (?) Perhaps Soda-alum mixed with Al S 2 + 9 H. (NH*'S + Ai S 3 ) + 24 H. (Mg'S + Al's 3 ) + 22 H. (?) u (U),'s, H. (MnS + AlS 3 ) + 24 H. [(Mg, Mn) *S'+ Al S 3 ] + 24 H. Fe 8' + 7 H. Fe iS 3 ' + 9 fi. + 18 H. (?) 2 Fe S 2 + 21 H. (?) Fe 2 s' + 6 H. Fes s's + 27 H = (2 F3 S 2 + 21 H) + (Fe S' + H). (?) (2 Pc2's8 + Fe S) + 3 H. (?) [(Fe, Mg, K/S + (Al, Fe) S 3 ] + 24 H. [3 (Fe, K)'S + 2 (Fe, Al) S 3 J + 12 H. (ks'+4FVS) + 9 H. OP MINERALS. 56S fc) Containing Soda (Na'S + 4FeS) + 9 H. , 37 Pissophane y. Fe, AI, S*, H. 238 Botiyogene Fe, Mg, Fe, *8, H. 244 Bieberite Co 2 S'+ 8 H (?) and (Mg *s'+ 7 H) + 3 (Co S'+ 7 H). 243 Goslarite Zn's + 7 H. 809 Anglesite Pb S*. 242 Cyanose Cu*S*+ 5 H. 301 Brochantite Cu S* + 3 Cu H. 813 Copper-lead vi- triol Pb S"+ Cu H. (?) (Linarite.) 6) Sulphates with Chlorides. 233 Martinsite Mg S"+ 10 Na Cl. (?) c) Sulphates with Fluoridei. Baryt-fluor-spar Ba*S + 3 Ca Fl. (?) d) Sulphates with Silicates. 43 Nosean ......... Na, Ai, si/S, Cl. (?) 42 Haiiyne 45 Lapis Lazuli ... f. K, Na, Ca, Ai, Si, S\ Cl. 44 JL^WU\vC*JJ- **t*i* ^VV| ~~7 kJJ -} ^J ^^ V*y Haiiyne "J Lapis Lazuli ... ( K, Na, Ca, Ai, Si, *s| Ittnerite j e) Sulphates with Carbonates. Calstronbaryte B*a*S + (Sr, Ca) C. (?) 221 Barytes, Suipha- to-carbonate of Ba *S* + 2 Ba C. (?) 311 Lanarkite Pbs'+PbC. 810 Leadhillite .. Pb S*+ 3 Pb C. 564 CHEMICAL ARRANGEMENT 312 Caledonite 2 (Pb S*+ Pb C) + (Pb S*+ Cu C. (?) 327 Bismuthite Bi, sj C. /) Sulphates with Arseniates. 276 Iron sinter.* a) From Frei- berg (Pe S 2 + 15 H) + (Fe 3 As 2 + 15 H). ) From Gas- 3 (Fe 2 *S + 5 H) + 5 (Fes As + 5 H). tein Coinp. Arseniates. g) Sulphates with Phosphates. 277 DiadocMte ...* 3 (Pe s" + 12 H) + (Pe* p's + 18 H. B. Minerals with the Composition of Organic Bodies. 1 I. Oils. 485 Mineral oil (Naph- C, H. Mixture of Paraffine with fluid tha) Carburetted Hydrogen. II. Resins. 490 Amber C, H, (X Bitumen, two Resins, an Ether oil, Succinic acid. 487 Asphaltum C, H, O. Asphaltine (C 20 H 32 O 3 ) and Resin. 485 Petroleum Asphaltine and Petroline (C 10 H 16 ). 491 Retinite C, H, O. Bitumen and Resins. (Fossil Copal, Piau- zite.) 492 R. from Walchow C 12 H 18 O. Schrotter. - Giron C 34 H 53 O 2 . Boussing. 493 - Highgate Hill ... C 40 H C4 O. Johnston. 493 - Settling f Stones C 2 H 3 . J. 1 Strictly, Mellite and Oxalite also belong to this division. OF MINERALS. 566 494 Berengellite C 40 H 62 O 8 . 495 Guayaquillite C 20 H 26 O 8 . 497 Middletonite _ C 20 H 22 O. 486 Elaterite ~ Chief constituent perhaps CH. 498 Ozokerite (Mineral^ wax) (.CH. 499 Hatchetine J 504 Idrialine C 42 H 28 O: Bodecker. 504 Idryl C 3 H 2 . 503 Scheererite, from Uznach CH 4 . (?) 502 Konlite, from Uz- nach and Red- witz C 2 H 2 . Tromsd. Kraus. 500 Fichtelite, from Redwitz C 4 H 6 . Xyloretine C 23 H 38 O 8 . Schrott 503 Tekoretine C 5 H 9 . Forch. 503 Phylloretine C 4 H 5 . Forch. 501 Hartite C 6 H 10 . Schrotter. Ob => Tekoretine ? 496 Hartine C 20 H 54 O 2 . 495 Bogbutter C, H, O. Ill Coals. 483 Brown coal.. 482 Stone coal 481 Anthracite .. (C, H, 0,N. A. Zygadite. A reddish or yellowish-white mineral, much resem- bling albite, and occurring in macles formed by the same law, in a mine near Andreasberg. H. under 6 ; G. = 2*511. Sub- translucent, and lustre vitreous, inclining to pearly on the dis- tinct cleavage planes. B. Ahifnocalcite. Massive and friable ; white*, slightly yellowish, bluish, or reddish. G. = 2-148 2-1 74. Occurs at Eubenstock in Saxony. C. Perthite, Thomson. Probably a variety of felspar ; from Perth in Upper Canada. 566 CHEMICAL ARRANGEMENT OF MINERALS. D. Thuringite, Breithaupt. Massive, with cleavage in one direction. H. = 2 2-5 ; G. = 3'151 3-157. Pearly lustre ; olive-green ; streak siskin-green. Gelatinizes in hydrochloric acid. From Schmeidefeld near Saalfeld in Thuringia ; and seems closely con- nected with lievrite, No. 175. E. Chamoisite, probably a mixture of magnetic iron-ore with hydrous silicates of alumina ; from Chamoison in the Valais. Malthazite. A white tallow-like substance-, from Lobau in the Lausitz. F. Iberite, Svanberg. Probably hexagonal ; with cleavage along ooP and OP. H. = 2-5 ; G. = 2-89. Opaque, resinous, light- green, or gray. B.B. fuses difficultly to a dark glass. With borax shows traces of iron, and becomes dark-blue with cobalt solution. Noiiin found 4O90 silica, 30-74 alumina, 15*47 iron protoxide, 1'33 manganese protoxide, 0'40 lime, 0-80 magnesia, 4-57 potash, 0'04 soda, and 5'57 water (= 99'82). It occurs at Montalvan near Toledo in Spain. G. Diphanite, Nordenskiold, from the emerald mines of the Ural. It resembles apatite. G. = 3'04 3'07. B.B. becomes opaque, exfoliates, and forms an enamel. Jewreiuoff found in it 34-02 silica, 43*33 alumina, 13-11 lime, 3"02 iron protoxide, 1 '05 man- ganese protoxide, and 5-34 water (= 99-87). H. Yttria-Spar, Hartmann, occurs as a white incrustation on Gado- linite and other minerals from Ytterby in Sweden. I. Borocalcite. This salt occurs in fine acicular crystals, white or colourless, near Yquique in South America ; and, according to Hayes, contains 18'89 lime, 46-11 boracic acid, and 35-00 water (100). K. Mosandrite, Erdmann. Indistinct prismatic crystals ; with one distinct and several indistinct cleavage planes. H.=4 ; G.=- 2*93 2*98. Translucent in thin splinters ; lustre resinous ; colour dark reddish-brown ; streak greyish-brown. In the closed tube gives much water. B.B. intumesces and fuses to a brownish- green bead ; with borax forms an amethystine glass, which in the reducing flame becomes yellowish or almost colourless. Found on Lamoe near Brevig in Norway. L. Cryptolite, Wohler. Found in transparent, pale wine-yellow, acicular crystals, imbedded in the compact apatite of Arendal, and shown by dissolving the latter in nitric acid. G. about 4-6. Unaltered at a red heat. Powder soluble in concentrated sulphuric acid. Wohler found 7370 cerium oxide, 1"51 iron protoxide, and 27*37 phosphoric acid (= 102 -58). INDEX OF SIMPLE MINEKALS. ABICHITE, 360. Amethyst, 111. Arfvedsonite, 203. Abrazite, 174. Acadialite, 172. Amianthus, 201, 206. Ammonia, Muriate of, 336. Argent antimonie sulphure, 493. Achmite, 214. Sulphate, 336. Argent chlorure, 389. Achroite, 266. Ammoniac-salt, 336. Argent en epis, 474. Aciculite, 48?. Amoibite, 459. Argent iodure, 391. Actinolite 200. Amoniak-alaun, 322. natif, 439. Actinote, 200 Amphibole, 199. sulfure, 472. Adiaphane spar, 142, 145. Adinole, 125. Adularia, 119. Amphigene, 154. Amphigenespar, 154, 155, 156. Amphodelite, 128. Argentite, 472. Argille ochreuse jaune, 222. Arquerite, 442. Aechynite, 283. Analcime, 159. Arragonite, 294. Aedelforsite, 165. Anatase, 416. Arsen, 442. Aedilite, 144. Anauxite, 198. Arseneisensinter, 350. Aegirin, 203. Andalusite, 242. Arsenic, 442. Aeschynite, 283. Andesin, 125. Acid, 432. Agalinatolite, 227. Anglarite, 369. Oxide of, 432. Agate, 114. Anglesite, 376. sulfure, 504. Alabandine, 498. Anhydrite, 315. Arsenic-antimony, 442. Alabaster, 315. Ankerite, 342. Arsenic-glance, 443. Alaun, 321. Alaunstein, 151. Anorthite, 128. Anthophyllite, 201. Arsenic-silver, 443. Arsenikalkies, 453. Albin, 169. A nthosiderite, 273. Arsenikbluthe, 318, 432. Albite, 123. Anthracite, 509. Arsenikkies, 454. Alkali, Mineral, 330. Anthraconite, 289. Arseniosiderite, 365. Allagite, 212. Antigorite, 187. Arsenite, 432. Allanite, 277- Allochroite, 232. Antimoine natif, 442. oxide, 427. Arsenkupfer, 467- Asbestus, 201. Allogonit, 303. sulfure, 458. Asparagus stone, 303. Allomorphite, 309. Allophane, 223. sulfure, 479, 483. Antimon, 442. Asphaltum, 516. Asteria, 253. Alluaudite, 350. Antimon-arsen, 442. Astrakanite, 338. Almandine garnet, 230, 233. Antimonblende, 485. Atacamite, 364. Almandine spar, 158. Antimonbliithe, 432. Augite, 204. Alstonite, 310. Altaite, 476. Antimonglanz, 479. Antimonnickel, 461. Augite-spar, 199, 204, 216, 236 Auiichalcite, 356. Alum, 321. Antimony, 442. Auripigmentum, 504. Ammonia, 322. Arsenical, 442. Automalite, 251. Feather, 322. Iron, 322. Baryte, 432. -Ochre, 427. Avanturine, quartz, 111. Felspar, 129. Magnesia, 322. Oxide of, 432. Axinite, 239. Potash, 321. Red, 485. Azure Spar, 146, 147. Soda, 322. -Silver, 440. Azurite, 146, 353. Alum Haloid, 151. Sulphuretsof, 479, 483, 491 Alumacalcite, 565. Alumina, Mellate of, 524. "White, 432. Antimony-Glance, 479, 492. Babingtonite, 216. Baierine, 409. Subsulphate of, 152. Sulphate of, 323. Alumine, fluate, 299. Antimony-Ores, Grey, family 479, 4H8. Antrimolite, 162. Baikalite, 205. Balas Ruby, 25J. Baltimorite, 189. Alumine sulfatee, 323. Apatelite, 327. Bamlite, 242. Aluminite, 152. Apatite, 31)1. Barsowite, 138. Alumstone,-151 Magnesia, 303. Barystrontianite, 313. Alun, 321. Pseudo, 303. Barytes, 307. Alunite, 151. Aphanese, 360. Barytes, Bicalcareo-carbonate Alunogene, 323. Aphrite, 289. of, 311. Amalgam, 441. Amazon-stone, 120. Amber, 518. Aphrodite, 229. Aphthalose, 337. Apophyllite, 168. Carbonate of, 309. Sulphate of, 307. Sulphato-carbonate of ,310 Amblygonite, 150. Amblygoa-spar, 150. Aquamarine, 260. Arcanite, 337. Barytocalcite, 310. Baryto-celestine, 312. 568 INDEX OF Batrachite, 270. Braunite, 422. Chalilite, 224, 163. Beaumontite, 166. Braunsalz, 328. Chalk, 290. Bell metal ore, 496. Braunstein, Grauer, 419, 421 Black, 219. Beraunite, 349- Bother, 342. Chamoisite, MC<. Berengelite, 520. Breislackite, 203. Chaux, arseniate, 318, 31S, Bergmannite, 160. Breithauptite, 461. carbonated, 286. Bergmehl, 118. Breunnerite, 293. magnesifere, 290. Bergseife, 220. Brevicite, 162. Chert, 113. Beryl, 259. Brewsterite, 166. Chiastolite, 248. Bernstein, 518. Brown coal, 513. Childrenite, 304. Berthierite, 485. Brythine-allophane, 424. Chiolite, 30J. Berzeline, 475. Brythine salt, 3K>, 317. Chloanthite, 463. Berzeliite, 319. Bryt.hyne spar, 176. Chlorite, 182, 183. Berzeiite, 380. Brochantite, 367. Chlorite-spar, 182. Beudantite, 141, 366. Bromite, 391. Chlorttoid, 182. Bieberite, 329. Broinsilber, 391. Chloromelan, 193. Bildstein, 227. Brongniartin, 317. Chloropal, 274. Bimstein, 135. Bronzite, 209. Chlorophaeite, 275. Biotite, 180. Vanadine, 211. Chlorophane, 293. Bismuth, 445. Brookite, 415. Chlorophyllite, 263. Cupreous, 496. Brown spar, 339. Chlorospinel, 251. Telluric, 477. Brucite, 194, 271. Chondrodite, 271. Silicate of, 276. Bucholzite, 243. Chonikrite, 191. Sulphuret of, 486, 487- Bucklandite, 239. Chromeisenstein, 396. Bismuth-blende, 276. Bismuth-glance, 486, 47. Buntkupfererz, 466. Buratite, 356. Chromite, 396. - Chrome-ochre, 429. Bismuthine, 486. Bustamite, 211. Chrome-ore, 398. Bismuthite, 389. Byssolite, 201. Chrome, Oxide of, 429. Bismuth ochre, 427- Bytownite, 139. Chromestone, 429. Bittersalt, 337- Chrysoberyl, 254. Bitterspar, 290, 292. Cacholong, 117. Chrysocolla, 352. Bitumen, 515, 516. Elastic, 516. Cairngorum stone, 111. Calais. 147. Chrysolite, 268, 271. Chrysophane, 196. Black lead, 508. Calaite, 147. Chrysoprase, 114. Blackjack (= Blende), 496. Calamine, 344. Chrysotile, 189. Blattertellur, 476. Calamine electric, 346. Chusite, 270. Blaueisenerde, 368. Calamite, 199. Cimolite, 227. Blaueisenstein, 215. Calcareous spar, 286. Cinabre, 503. Blauspath, 146. Calcedony, 114. Cinnabar, 503. Blei, 445. Calc-spar family, 286296. Cinnamon stone, 232. Bleiantimonerz, 481. 286. Cipollino, 289. Bleierde, 375. Caledonite. 378. Citrin, 111. Bleiglanz, 468. Calomel, 390. Clausthalit?, 470. Bleiglatte, 429. Cancrinite, 141. Clay, family, 218230. Bleigummi, 386. Candite, 251. Clay, 219. Bleilasur, 379. Caporcianite, 162. Cleavelandite, 123. Bleinierite, 383. Carnat, 225. Clintonite, 196. Bleischimmer, 481. Carnelian, 114. Cluthalite, 160. Bleivitriol, 376. Cassiterite, 406. Coals, family, 508515. Blende, 493. Cassiterotantalite, 411. Coal, Anthracite, 509. Blendes, family, 496499. Catlinite, 228. Bituminous, 511. Bloodstone, 114. Cat's eye, 111. Brown, 513. Blue John, 298. Cavolinite, 141. Common, 511. Blutstein, 397. Cawk, 309. Glance, 509. Bog-butter, 521. Celestine, 311. Colestin, 311. Bole, 224. Cerasite, 380. Cobalt, arseniate, 372. Bolognese stone, 309. Cererite, 2/9. arsenical, 456. Boltonite, 247. Cerin, 277. Bright white, 455. Bonsdorfite, 263. Cerinstein, 279. Earthy, 373, 425, 426. Boracic acid, 333. Cerite, 2/9. glance, 455. Boracite, 304. Cerium baryte, 298. gris, 455. Borax, 332. Carbonate of, 344. Red (= Erythrine), 372. Bornite, 466, 478. Fluate of, 299. Sulphate of, 329. Borocalcite, 666. ore, Mohs, 279. Sulphuret of, 457. Botryogene, 325. ^erusse, 374. Tin white, 456. Botryogen salt, 325. [!erussite, 374. White, 455. Botryolite, 307- Heylanite, Cobalt-bloom, 372. Boulangerite. 482. Chabasie, 170. Cobaltine, 455. Bournonite, 491. Chabasite, 170. Cobalt ochre, 426. Branchite, 523. Chalcolite, 371. Coccinite, 391. Braunbleierz, 381. Braur.eisenstein, 400. Chalcophacite, 358. Chalcophyllite, 356. Coccolite, 206. Colcothar of iron, 325. Braunerz, 401. Chalcopyrite, 464. Colophonite, 233. Braunkohle, 513. Chalcotrichite, 430. Columbite, 409. SIMPLE MINERALS. 5(>9 Comptonite, 163. Cuivre, sulfure, 473. Eisenthon, 220. Condrodite, 271. Cummingtonite, 238. Eisen-vitriol, 325. Condurrite, 467- Cuprite, 430. Ekebergite, 137. Conite. 291. Cuproplumbite, 469. Elasolite, 140. Copal, fossil, 520. Cyanite, 240. Elain-spar, 136, 140, 141. Copaline, 520. Cyanose, 328. Elaterite, 516. Copiapite, 326. CynTophane, 254. Electric calamjne, 346. Copper, Native, 445. Cyprine, 23G. Electrum, 438. Antimonial, 484. Embrithite, 482. Arseniates of, 356, 358, Damourite, 163. Emerald, 259. 359, 360. Danaite, i55. Emerald, Mohs, 258, 259, Black, 425. Danburite, 170. 260. Blue, 353, 474. Datholite, 306. Emeraude, 259. Capillary red oxide of, Davyne, 141. Emery, 253. 430. Delvauxerie, 351. Emmonite, 313. Carbonate of, 353, 354. Demant, 507. Endellionite, 492. Emerald, 352. Demantspath, 252. Epidote, 236. Ferruginous red oxide of, 401. Dermatin, 229. Desmine, 164. Epistilbite* 167- Epsomite, 337- Glance, 4/3. 492. Devonite, 148. Epsom-salt, 337- Grey, 489. Diaclasite, 211. Erdkobalt, 372, 426. Muriate of, 364. Diadochite, 351. Erdkohle, 513. Oxydulated, 430. Diallage, 209, 210. Erdol, 515. Phosphate of, 361, 362. Diallogite, 342. Erdpech, 516. Purple, 466. Diamant, 507. Eremite, 284. Seleniuret of, 475. Diamond, 507. Erinite, Thomson, 221, Sulphate of, 328, 368. Sulphurets of, 464, 466, Diamond-blende, Mohs, 276. Diaspore, 245. Haidinger, 357. Erythrine, 372. 473. Copper, 362. Erythrite, 121. Variegated, 466. Vitreous, 473. Dichroite, 261. Digenite, 474. Esmarkite, 263. Etain oxyd6, 406. Copper and Silver, Seleniuret of, 475. Dihydrite, 362. Diopside, 205. sulfure', 495. Euchlore-Malachite, 356, 371. Sulphuret of, 473. Dioptase, 352. Euchlore-Salt, 330. Copperas, 325. Copper froth, 357. Dioxylite (== Lanark! te), 378. Diphanite, 566. Euchroite, 360. Euclase, 258. Copper-green, 352. Diploite, 453. Euclase Haloid, 313, 318, 372. Copper mica, 356. Dipyr, 140. Eudialite, 158. Copper nickel, 461. Copper ore, 430. Disterrite, 198. Disthene.^O. Eugenglanz, 494. Eukaifite, 475. Copper ore, Grey, family, 489 496. Disthene-Spar, 245. Dolomie, 290, 342. Eulytine, 276. Eutome-glance, 476, 478, 494. Red, 430. Dolomite, 290. Euxenite, 412. Yellow, 464. Domeykite, 467. Exanthalose, 324. Copper pyrites, 464. Copper Salts family, 352374. Dreelite, 309. Dufrenite, 370. Fahlerz, 489. Copper-Uranite, 371. Coquimbite, 327. Dufrenoysite, 484. Dysclasite, 169. Fahlore, 489. Fahlunite, 263. Cordierite, 2(il. Dysluite, 397. Hard, 262. Corindon, 252. Dystome-glance, 481, 489, Fassaite, 205. Corundum, 252. 492, 495. Faujasite, 172. Corundum, Mohs, 249, 251, Dystome-spar, 150, 306. Fayalite, 270. 254. Feather-alum, 322, 353. Cotunnite, 380. Edingtonite, 176. Feaiher-ore, 483. Couzeranite, 12?. Edwardsite, 284. Federalaun, 322, 323. Covelline, 474. Egeran, 236. Federerz, 483. Crednerite, 424. Ehlite, 363. Feldstein, 122. Crichtonite, 405. Eisen, Gediegen, 446. Feldspath, 118. Crocoisite, 307- Cronstedtite, 193. Eiscn-apatite, 348. Eisenblau, 368. Empyrodoxer, 122. resinite, 13(5. Cross-stone, 172. Eisenbliithe, 294. Felspar family, 118136, Cryolite, 299. Eisenglanz, 397- general characters, 130. Cryptolite, 566. Eisenglimmer, 398. Common, 1-20. Cuban, 406. Eisenkies, 449. Compact, 122. Cube-ore, 365. Eisenkiesel, 112. Glassy, 121. Cuboit, 160, Eisennickelkies, 464. Felspar, Mohs, 118, 123,126, Cuivre, Arseniurede, 467. Eisenoxyd, Schwefelsaures, 128, 129. carbonate, 353, 354. 32.'j, 327. Fer arse'niate', 365. chlorure, 364. Eisenpeeherz, 34?, 350. carburd, 508. gris, 489. Eiscnrose, 39.0. chromate", 396. natif, 445. Eisenrahm, 398. muriate, 193. oxydule, 430. Eisensinter, 350. natif, 446. pyriteux, 464. Eisenspath, 339. oligiste, 397- sulfate, 328. Eisensteinmark, 224. oxalate, 524 SB 570 INDEX OF Fer oxid6 resinite, 350. Gokumite, 236. Hisingerite, 273. oxydule, 394. Gold, 436. Hohlspath, 243. phosphate, 368. Goslarite, 329. Holmesite, 196. sulfate, 325. Gotheite, 402. Honey Stone, 524. sulfure, 449. Gotthardtite, 484. Honigstein, 524. Fergusonite, 413. Grammatite, 199. Hopeite, 301. Ferrotantalite, 411. Granat, 230. Hornblei, 379. Fettbol, 224. Graphite, 508. Hornblende family, 199 Feuerblende, 502. Graubraunstein, 419. 218. Feuerstein, 113. Graugiltigerz, 489. Hornblende, 199, 202. Fibroferrite, 326. Grausilber, 390. Hornerz, 389. Fibrolite, 243. Fichtelite, 522. Grauspiessglaserz, 479. Green earth, 221. Horn-manganese; 212. Hornstone, 113. Figure stone, 227- Fischerite, 148. Green iron earth, 276, 370. Greenockite, 499. Houille, 511. Humboldtilite, 142. Flint, 113. Greenovite, 415. Humboldtine, 524. Flinty-slate, 113. Flos ferri, 294, 296. Grenat, 230. Grenatite, 244. Humite, 271. Htireaulite, 349. Flucerine, 229. Groroilite, 426. Huronite, 144. Fluellite, 301. Grossular, 231. Hyacinth, 249. Fluocerine, 299. Griinauite, 458. Hyalite, 116. Fluocerite, 299. Grunbleierz, 381. Hyalosiderite, 2fi9. Fluor Spar family, 297307- Fluor-spar, 297. Gruneisenstein, 370. Grunerde, 221. Hydrargillite, 24tf. Hydroboracite, 306. Fluor Haloid, 297, 301, 303, Gummierz, 418. Hydromagnesite, 195. 366. Gurhofian. 292. Hydromagnocalcite, 195. Fluss-spath, 297- Guyaquillite, 521. Hydrophane, 117- Fowlente, 212. Gymnite, 191. Hydrophite, 187, 212. Frankenberg corn-ears, 474. Franklin ite, 396. Gypsum family, 313319. Gypsum, 313. Hypargyron blende, 502. Hypersthene, 208. Fraueneis, 313. Hypochlorite, 276. Freieslebenite, 492. Haarkies, 463. Hypostilbite, 165. Frugardite, 236. Haarsalz, 323. Hystatit, 405. Fuchsite, 178. Habroneme-malachite, 354. Fuller's earth, 222. Habroneme-ore, 400. Iberite, 566. Furnace slags, 236, 270. Haematite, 397. Brown, 400. Ice spar, 119, 122. Iceland spar, 289. Gadolinite, 276. Gahnite, 230, 251. Hafnefiordite, 130. Haidingerite, 319, 485. Ichthyophthalm, 169. Idocrase, 235. Galena, 468. Hair-salt, 323. Idrialine, 523. Galmei, 344, 346. Hal-Baryte, 307, 310, 312. Idrialite, 523. Garnet family, 230248. Garnet, 230. Haloid-stones, 146159. Halotrichite, 323^ Idryl, 523. llmenite, 404, 284. Garnet-blende, 496. Halloysite, 222. Ilvaite, 272. Gaylussite, 332. Harmotome, 172. Indianite, 128. Gehlenite, 142. Lime or Potash, 173. Indicolite, 268. Gekrosstein, 316. Gelbbleierz, 385. Harrington ite, 162. Hartbraunstein, 422. lodinsilber, 391. lodite, 391. Gelbeisenerz, 327. Hartine, 521. lodquecksilber, 391. Gelbeisen stein, 401. Hartite, 522. lolite, 261. Gelberde, 222. Hartkobalterz, 457. Iridium, 435, 436. Gems family, 248272. Hatchetine, 522. Iridosmium, 436. Geokronite, 483. Hauerite, 499. Irite, 399. Gersdorffite, 459. Hausmannite, 421. Iron, 446. Gibbsite, 246. Hauyne, 156. Arseniate of, 365. Gieseckite, 263. Heavy-spar family, 307313. Cupreous, 36?. Gigantolite, 264. Gipsite, 246. Heavy- spar, 307. Hedenbergite, 206. Blue, 3 18. Carbonate of, 339. Giobertite, 293. Girasol, 117 Hedgehogstone, 403. Hedyphane, 383. Chromate of, 394. Hydrous oxide of, 402. Gismondine, 174. Heliotrope, 114. Magnetic, 394. Glance-blende, 498. Helvine, 234. Meteoric, 447. Glance-coal, 509. Hepatite, 309. Nickel-pyrites, 464. Glanzbruunstein, 421. Hercinite, 251. Oxalate of, 524. Glaskopf, rother, 398. brauner, 400. Herderite, 303. Herschelite, 174. Oxydulated, 394. Peroxide of, 39?. Glatte, 429. Herrerite, 345. Phosphate of, 368. Glauberite, 317- Hessite, 477. Pyrites, 449. Glaubersalt, 324. Glaucolite, 127. Hessonite, 232. Hetepozite, 349. Sparry, 339. Specular, 397, 398. Glauconite, 221. Glim7ner, 177. Heterocline, 422. Heterozite, 349. Sulphate of, 325. Sulphuretof, 449. Glottalite, 176. Heulandite, 165. Telluric, 446. Gmelimte, 170. Highgate resin, 520 Titanitic, 404. SIMPLE MINERALS. 571 Iron, Tungstate of, 408. Kobaltbllithe, 372. Lead, Sulphate-carbonates of, Iron-clay, 220. Kobaltkies, 457. 377, 378. Iron-flint, 112. Iron-froth, 398. Kobaltglanz, 455. Kobaltvitriol, 3*9. Sulphuret of, 468. Superoxyd of, 418. Iron-mica, 398. Kobellite, 487. Supersulphuret of, 469. Iron-ore, 398. Kochsalz, 319. Tungstate of, 386. Bog, 401. Kollyrite, 225. Vanadiate of, 384. Brown, 400, 402. Konlite, 523. White, 3/4. Green, 370. Kbnigine, 3G8. Lead- Bar yte, 374, 377, 3?8, Magnetic, 394. Korallenerz, 504. 379, 380, 382, 385, 386. Ochrey, 398. Korund, 252. Lead Glance family, 468 179. Pitchy, 350. Koupholite, 143. Lead -glance, Alohs, 4(j8, etc., Red, 398. Krablite, 135. 483. Yellow, 327. Kreuzstein, 172. Leadhillite, 377- Iron-ore, M ohs, 394, 396, 404, Krisolith, 268. Lead-ochre, 4^9. 405. Krisuvigite, 368. Lead-ore, Green, 381. Iron-pyrites, 449. Krokidolite, 215. Bed, 387. magnetic, 452. Krokoit, 387. White, 374. white, 451. Iron-sand, 405. Kryolith, 299. Kupfer, 444. Yellow, 385. Lead-Salts family, 374393. Iron-sinter, 350. Ironstone, Blue, 215. Clay, 341. Iserine, 285. Kupfer-antimonglanz, 484. Kupferblau, 353. Kui-ferblende,-491. Kupferbliithe, 430. Lead-spar, 374. 387. Lead-vitriol, 376. . Lebererz, 503. Leberkies, 451. Isophane, 397 Kupferbraun, 401, 431. Lederite, 172. Isopyre, 217- Kupferglimmer, 356. Leelite, 122. Ittnerite, 157. Kupferglanz, 473. Lehm, 219. Ixolyte, 518. Kupfergrun, 352. Kupferindig, 474. Lehuntite, 162. Lemnian earth, 220. Jade, 145. Kupferkies, 464. Lenzinite, 222. Jamesonite, 480. Kupferlasur, 353. Leonhardite, 176. Jargon (= Zircon), 248. Jasper, 112. Jaspis, 112. Jayet, 513. Kupfermanganerz, 424. Kupfernickel, 461. Kupferpecherz, 401. Kupferschaum, 357- Lepidokrokite, 401. Lepidolite, 179. Lepidomelane, 181. Leucite family, 154159. Jeffersonite, 206. Kupferschwarze, 425. Leucite, 154. Jet, 513. Johannite, 330. Kupfer Smarargd, 352. Kupfer Uranite, 371. Leuchtenbergite, 184. Leucophane, 257- Junkerite, 341. Kupfervitriol, 328. Leucopyrite, 453. Kuphon-mica, 194. Levyne, 170. Kakoxene, 149, 349. Kalisalpeter, 333. Kuphone spar, 159, 160, 163, 164, 165, 167, 168, 172, Libethenite, 362. Lievrite, 272. Kalisulphat, 33?. 173, 175. Lignite, 513. Kalk, Kohlensaurer, 286. Kuphon Haloid, 332. Limbelite, 2/0. Kalkmalachit, 355. Kyanite, 240. Lime, Arseniate of, 318. Kalk-spath, 286. Kymatine, 201. Borate of, 306. Kammererite, 192. Kyrosite, 452. Carbonate of, 26. Kammkies, 451. Fluate of, 297- Kampylite, 383. Labradorite, 126. Nitrate of, 335, Kaneelstein, 232. Lanarkite, 378. OxaLite of, 525. Kaolin, 218, 122. Lanthanite;344. Phosphate of, 301. Kapnite, 345. Lapis lacedaemonius, 129. Silicate of, 213.! Karpholite, 216. Lapis-lazuli, 157. Sulphate of, 313. Karphosiderite, 351. Lasionite, 148. Tungstate of, 392. Karstenite, 315. Lasurstein, \:fj. Lime Haloid, 286, 290, 2U3, Kastor, 133. Latrobite, 153. 294. Keilhauite, 281. Laumonite, 175- Limonite, 400. Kerate, 389. Lavendulan, 373. Linarite, 379. Kermes, 485. Lazulite, 146, 157. Linneite, 457. Kerolite, 226. Lazurspath, 146. Lin&enerz, 358. Kibdelophan, 405. Lead, 444. Liroconite, 358. Kieselguhr, 118. Aluminate of, 386. Lithiamica, 179. Kieselmalachit, 3te. Arseniate of, 382. Lithomarge, 225. Kieselwismuth, 276. Carbonate, 374. Hard, 224. Kieskobold, 457. Chromate of, 3fi7- Loam, 219. Kilbrickenite, 483. and copper, 388. Loboite, 236. Killinite, 132. Corneous, 379. Lolingite, 453. Kimito-tantalite, 411. Kirwanite, 144. Molybd;!te of, 385. Muriate of, 380. Loxoclase. 130. Luchssapphir, 262. Klaprothine, 146. Murio-carbonate of, 379. Lucullite, 289. Klebschiefer, U8. Oxides, 428, 4*9. Lumachello, 289. Klinoclase, 360. Phosphate of, 381. Lydian stone, 112. Knebellite, 2/0. Selemuret of, 470. Lyncurius, 249. Kobaltbeschlag, 373. Sulphates of, 376, 379. 572 INDEX OF Maclurite, 271. Melopsite, 226. Mullerine, 488. Magnesia, Borate of, 304. Menaccanite, 405. Mullicite, 369. Carbonate of, 228, 293. Menakerz, 413. Murchisonite, 121. Fluophosphate of, 150. Mendipite. 380. Muriazit, 315. Hydrate of, 194. Mengite, 284. Myelin, 226. Native, 194. Menilite, 117- Mysorine, 355. Nitrate of, 335. Mennige, 428. Silicate of, 247. Mercurblende, 503. Nacrite, 198. Sulphate of, 337. Magnesite, 293. Mercure argental, 441. chlorure, 390. Nadeleisenerz, 402. Nadelerz, 487. Magneteisen, 394. natif, 441 . Nagyagcrerz, 476. Magnetic iron, 394. Mercury, 441. Nagyagite, 476. pyrites, 452. Magnetite, 394. Chloride of, 390. lodic, 391. Naphtha, 515. Natrocalcite (= Gaylussite) Magnetkies, 452. Nitrate of, 391. 3)2. Ma'lacolite, 205. Sulphuret of, 503. Natrolite, 160. Malachite, 354. Mesi tine-spar, 294. Natron, 330. Mohs, 352, 353, 354, 358, Mesolc, 162. Natronsalpeter, 334. 360, 361, 362, 363, 365, Mesolite, 162. Natronsalt, 330. 367, 388. Mesotype, KiO. Natrumalaun, 322. Malachite, Emerald, 352. Lime, 161. Naumannite, 471. Euchlore, 356, 357, 371. Metallic stones family, 272 Needleore, 487. Green, 354. 286. Needle-spar, 294. Lasur, 353, 379. Metals, Native, 433449. Needlestone, 161. Lime, 355. Metaxite, 187, 189. Nemalite, 196. Siliceous, 353. Meteorites, 448. Neoctese, 367- Malachitkiesel, 353. Miargyrite, 500. Nepheline, 140. Malakon, 249. Malthazite, 566. Mica family, 177198. Lithia, 179. Nephrite, 145. Newkirkite, 426. Manganblende, 498. Magnesia, 180. Neurolite, 145. Manganese, Arseniuret of, Potash, 177- Nickel, Antimonial, 460, 468. Michaelite, 118. 461. Carbonate of, 342. Microlite, 281. arseniate, 373. Cupreous, 424. Middletonite, 521. Arsenical, 461. Earthy, 425. Grey, 421. Miemite, 292. Miesite, 382. Copper, 461. natif, 463. Oxide of, 419. Millerite, 463. Stibine, 460. Phosphate of, 347. Miloschin, 226. Sulphuret of, 463. Red, 342. Mimetene, 382. White, 462. Silicate of, 211, 212. Mimetesite, 382 Nickelarsenkies, 459. Sulphuret of, 493. Mine douce, 401. Nickel-Bismuth, 458. Manganese ores family, 413 426. Mineral Resins family, 515 524. Nickelbluthe, 373. Nickel-glance, 459. ore, Mohs, 419, 421, 422, Tallow, 522. Nickel-green, 373. 423. Minium, 428. Nickeline, 461. Manganese-spar, 211, 342. Mirabilite, 324. Nickelkies, 463. Manganite, 421. Mispickel, 454. Nickel-ochre, 373. Mangankalk, 343. Mangankupferoxyd, 424. Manganocalcite, 343. Misy, 327. Modumite, 457. Mohsite, 405. Nkkelwismuthglanz, 458. Nigrine, 416. Niobite, 409. Manganschaum, 425. Molybdanglanz, 4 <7 8. Nitratine, 334. Manganspath, 211, 342. ochre, 427. Nitre, 334. Marble, 289. Molybdan Silver, 478. Nitrocalcite, 335. Marcasite, 451. Molybdena ochre, 427. Nitromagnesite, 335. Marceline, 422. Oxide of, 427. Nontronite, 274. Margarite, 19S. Sulphuret of, 478. Nosean, 156. Marl, 290. Molybdene, 478. Nussierite, 382. Marmatite, 496. Molybdenite, 478. Nuttalite, 138. Marmolite, 189. Monazite, 284. Martinsite, 321. Monazitoid, 285. Obsidian, 134. Martite, 399. Monoclase Haloid, 301. Ochran, 224. Mascagnine, 336. Monradite, 190 Ochres, 42i5 430. Meerschaum, 228. Monticeilite, 270^ Ochre, yellow, 401. Meionite, 136. Moonstone, 120. Ochroite, 280. Melane glance. 493, 494. Morasterz, 401. Octaedrite, 416. Melane-ore, 272, 2/6, 277, Morion, 111. Oerstedtite, 281. 282, 413. Moroxite, 308. Okenite, 169. Melanite, 232. Morvenite, 173. Oligiste, 397. Melan-mica, 193. Mosandrite, 566. Oligoclase, 129. Melanochroite, 388. Mountain cork, 201. Oligon-spar, 340. Melanterite, 325. leather, 201. Olivenerz, 359, 362. Melichrone Resin, 524. meal, 1 18. Olivenite, 359. Mellilite, 142. wood, 201. Olivine, 268. Mellite, 524. Muller's glass, 116. Onegite, 403. SIMPLE MINERALS. 673 Onkosin, 145. Picrolite, 189. Pyreneite, 233. On of rite, 471. Picropharmacolite, 318. Pyrite, 449. Onyx, 114. Picrophyll, 190- Pyrites family, 449 408. Oolite, 284. Picrosmme, 189. Arsenical, 453. Oosite, 264. Picrosmine-steatite, 189. Capillary, 463. Opal, 115. Pimelite, 229. Cocks-comb, 452. Opaline-allophane, 223. Pifi^uite, 274. Hepatic, 452. Ophite, 187. Finite, 263. Iron, 449. Or natif, 436. Piotin (Soapstone), 227. Magnetic Iron, 452. Orpimont, 504. Orthite, 277. Pipe clay, 2 19. Pipestone, 228. White Iron, 451. Pyrochlore, 280. Orthoclase, 118. Pisolite, 290. Pyrolusite, 419. Orthoclase Haloid, 299, 315. Pissophane, 153. Pyromorphite, 381. Osmium-iridium, 435. Pistazite, 237. ' Pvrope, 232. Ostranite, 280. Pistomesite, 294. Pyropliyllite, 197. Ottrelite, 139. Pitchblende, 417. Pyrophysallite, 256. Ouro poudre, 438. Oxahverite, 169. Pitchstone, 136. Pitticite, 350. Pvrorthite, 2?9. Pyrosklerite, 192. Oxalite, 524. Pittinerz, 418. j Pyrosmalite, 193. Oxidized Iron ores family, Plakodine, 461. Pyroxene, 204. 394_40