UC-NRLF B M IflE 1 I O N WPJPE. BERKELEY LISRARY UNIVERSITY OF CALIFORNIA *- i EARTH SCIENCES LIBRARY if if REESE LIBRARY OF THE UNIVERSITY OF CALIFORNIA. Received. __ JL^ / S**^it^Jrrr <7 Accessions No.JL0JYO Shelf No. t* BCRKELE LISRAR UNIVERSITY < CALIFORNI/ ^ . EARTH SCIENCES LIBRARY PRACTICAL GUIDE TO THE DETERMINATION OF MINERALS BY THE BLOWPIPE. UNIVERSITY BY Dr. C. W. C. FUCHS, PROFESSOR IN THE UNIVERSITv'oF HEIDELBERG. Translated and Edited by T. W< DANBY, M.A., F.G.S., FELLOW OF DOWNING COLLEGE, CAMBRIDGE ; ASSOCIATE OF THE ROYAL SCHOOL OF MINES ; ETC., ETC, ETC. PRICE FIVE SHILLINGS. LONDON : PUBLISHED BY FIELD AND TUER, 50, LEADENHALL STREET, E.G.; SIMPKIN, MARSHALL, AND CO., STATIONERS' HALL COURT, E.G. PHILADELPHIA : CLAXTON, REMSKN, AND HAFFELFINGER, 624, 626, AND 628, MARKET STREET. AUTHOR'S PREFACE. HAVING, during several years in this university, given instruction in the recognition of mineralogical species, I have been led to write an Introduction to the Determination of Minerals. The work naturally divided itself into two portions : the one treating of the determination of minerals by the blow-pipe ; the other, explain- ing means of determining crystallized specimens, depending upon their physical characteristics. Each part in reality supplements the other, so that by a correct use of the two, no well defined species can escape recognition. My manuscript has long been used by the members of my own classes : the experience thus gained of the utility of my methods, encourages the hope that the present publication of them, will prove useful to a greatly increased number of students. The experiments suggested in the tables are so simple, that any one possessing some knowledge of crystal- lography, and a moderate familiarity with chemistry, will readily succeed in performing them without any special teaching. THE AUTHOR. Heidelberg, April, 1868. PREFACE TO THE ENGLISH EDITION. IN introducing to English readers this treatise on the practical application of blowpipe analysis, my aim has not been to super- sede, or compete with, the able and more exhaustive works on the same subject, already available in the language. These explain all that may be effected by a skilled chemist operating with the blow- pipe : while the present volume performs the humbler function of enabling any one, possessed of rudimentary acquaintance with the art of chemical manipulation, to recognise easily and certainly any fairly well-marked mineralogical species. I have endeavoured so to present Professor Fuchs' tractate that it shall be in the highest degree serviceable, not only to the student of mineralogical science, but also to the less purely scientific investigator, in the mine or the quarry. The original German work consists of two parts, the first treat- ing of the Determination of Minerals by the blowpipe; the second of their Determination, by means of crystallographical and other physical characters. The first part I have translated in its entirety : in place of the second, is appended a table giving the hardness, specific gravity, and crystallographical system of each species, so far as these latter are determined beyond question. This alteration I have ventured to effect, not because I underrate the value of crystallographical determinations ; but because in many cases in which this work will be most useful, e.g., in the field, such deter- minations are clearly impracticable. I have attempted to increase the usefulness of this volume, by interleaving portions of it, thus making it a blow-pipe manual and note book in one. There are two obstacles which present themselves in limine to any one writing or reading a work of this nature ; the perplexities Preface to the English Edition. v of chemical nomenclature and notation, and the bewildering abundance of synonyms. The formulas adopted in this translation are those of the German original, retained by M. Aug. Guerout, in his well-executed French translation. They are employed by Professor J. D. Dana, in the fifth edition of his "System of Mineralogy," and are prevalent in most English and foreign works on the subject. They rest on the atomic weights given in the annexed table, copied from Professor Dana's work. Aluminium Al ... 1375 Molybdenum ... Mo ... 46 Antimony (Stibium) Sb ... 122 Nickel Ni ... 29'5 Arsenic As ... 75 Niobium (Columbium)Nb ... 94 Barium Ba ... 68-5 Nitrogen ... ... N 14 Bismuth Bi ... 210 Osmium ... ... Os 99-5 Boron B ... II Oxygen ... ... O 8 Bromine Br ... 80 Palladium Pd ... 53 Cadmium Cd ... 56 Phosphorus ... P 31 Caesium Cs ... 133 Platinum Pt ... 98-94 Calcium Ca ... 20 Potassium (Kalium) K 39-11 Carbon C ... 6 Quicksilver = Mercury Cerium Ce ... 46 Rhodium Rh 52-16 Chlorine Cl ... 35-46 Rubidium Rb ... 85-4 Chromium ... Cr ... 26-24 Ruthenium Ru ... 52-16 Cobalt Co ... 29-5 Selenium Se 39'5 Copper (Cuprum} ... Cu .. 317 Silicium Si .,, 14 Didymium... D ... 48 Silver (Argentum) . Ag ... 108 Erbium E ... 56-3 Sodium (Natrium) . Na ... 23 Fluorine F ... 19 Strontium ... ... Sr 4375 Glucinum (Beryllium] Be ... 47 Sulphur S 16 Gold (Aurum) Au ... 196 Tantalum Ta ... 182 Hydrogen H ... i Tellurium ... ... Te 64-14 Indium In ... 35*9 Thallium Tl ... 203 Iodine I ... 127 Thorium ... ... Th 119 Iridium Ir ... 99 Tin(Stannum) ... Sn ... 59 Iron (Ferrum) Fe ... 28 Titanium Ti 25 Lanthanium .., La ... 46-4 Tungsten(lVolframium) W... 92 Lead (Plumbum} ... Pb ... 103-5 Uranium ... ... U 59'4 Lithium ... Li ... 7 Vanadium A 68-5 Magnesium Mg ... 12 Yttrium Y 32-18 Manganese Mn ... 27-5 Zinc ... ... Zn 32-53 Mercury(Hydrargyru) w)Hg... 100 Zirconium ... ... Zr 44-80 vi Preface to the English Edition. Chemists have doubled the atomic weights of certain elements : the names of these are italicised in the above list. The reader, conversant with the newer system of atomic weights, will find no difficulty in correcting in accordance with it, the formulae given in this volume. The multitude of synonyms unnecessarily heaped on certain minerals, is a disadvantage well nigh as grievous as that due to vagaries in chemical notation. In selecting the names inserted in the tables, my object has simply been to employ those which usage has rendered most familiar ; in the table at the end of the volume a certain number of the best known equivalent designations will be found. The names of the six crystallographical systems are those given in Professor VV. H. Miller's " Tract on Crystallography," the cor- responding expressions used by Professor J. D. Dana are as follows : MILLER. DANA. T. Cubic system - Isometric system. 2. Pyramidal Tetragonal . 3. Rhombohedral Hexagonal 4. Prismatic Orthorhombic 5. Oblique Monoclinic 6. Anorthic Triclinic I wish, in conclusion, to express my thanks to Professor C. W. C. Fuchs for the ready kindness with which he allowed me to render into English the '* Introduction to the Determination of Minerals,'" the value of which I first appreciated some years ago, when I enjoyed the privilege of the author's personal instruction. T. W. DAN BY. PRACTICAL GUIDE TO THE DETERMINATION OF MINERALS BY THE BLOWPIPE. THE object of the present volume is to facilitate the determina- tion of minerals. The crystallographical forms of minerals under investigation are generally so imperfect, small, or obscure, that their destruction is of no moment : such specimens may be advantageously determined by chemical means, among which a course of blowpipe testing will be found the most available for the purpose of the mineralogical student. This method is appli- cable in all, or nearly all cases ; t but when a specimen is interesting on account of the rarity of its faces, or valuable by reason of their perfection, the collector will naturally rely for his determination, upon goniometrical measurements and physical properties. BLOWPIPE ANALYSIS. The mineralogist will frequently be called upon to test newly acquired specimens, not only in the laboratory, with all the conveniences of chemical research around him, but in the field, near the spot where the mineral is found. Any process, then, to be of use to him, must depend upon the simplest means, and involve few and readily performed reactions. The chemist, with every appliance at hand, by means of more elaborate apparatus and more numerous tests, can easily repeat and confirm the process of determination. 8 Practical Guide to the Determination BLOWPIPE LAMP. For many reasons a gas flame would at once suggest itself as the most suitable for these experiments. But as gas is likely not to be available just when most needed, the student would do well to make himself independent by accustoming himself from the first to the use of a simple oil flame. Planner's lamp, or a still simpler one, with a broad wick, will be found convenient. Even the flame of a wax- candle will generally suffice. THE BLOWPIPE. The best modification of the blowpipe is one in which the nozzle, tube, and air chamber are separable ; such a one, if it can be easily taken to pieces and put together again, will be found very advantageous, especially in travelling. Every blowpipe should be furnished with two nozzles, with fine and large orifice respectively : the former will be most used in the deoxidizing, the latter in the oxidizing flame. APPARATUS. Charcoal. Good wood charcoal should ring clearly when struck : it is usually employed as support for the assay, especially when this is subjected to a reducing process. When the quantity of substance to be reduced is very small, the end of a wooden lucifer match will be found a convenient support. The end of the match is smeared with sodium carbonate, and the smeared wood charred by careful exposure to the flame. A small char- coal point coated with soda is thus obtained, the moistened assay can be readily affixed to this, and held in any required position in the flame. Glass Tubes. Small pieces of glass tubing, about 5 7 centi- metres long and 4 6 millimetres broad, and having one end closed by the blowpipe, will enable the operator to perform any required wet reactions, and also to examine the volatile products of substances heated without free access of air. Of Minerals by the Blowpipe. 9 Platinum Wire. This must be about as thick as a horsehair, and between 10 and 20 centimetres long. Smaller pieces may be rendered serviceable by fusing them into glass tubes as handles. Substances e.g.^ Pb, As, Bi, &c., which corrode Pla- tinum may be supported in the flame on asbestos. Platinum-foil. This should be about 14 18 millimetres wide, and 45 centimetres tong. Platinum Forceps. These will be of constant use in holding in the flame small fragments of minerals whose fusibility is to be tested, or whose effect on the colour of the flame is to be observed. Agate Mortar. A mortar of which the diameter is from 2 to 3 centimetres will be found to answer all requirements. Magnet. As a substitute for a magnet, the blade of a pocket knife may be magnetized and used in all respects as if it were a small bar magnet. REAGENTS. The Reagents mentioned in the following tables are Soda (= sodium carbonate). Borax. Microcosmic salt (hydric phosphate of sodium and ammonium). Hydrochloric acid (HC1) concentrated. Nitric acid (HONO 5 or UNO 3 ) dilute. Sulphuric acid (HOSO 3 or HW 4 ). Acetate of lead solution. Nitrate of cobalt solution. Potash (KOHO or KH<9), moderately concentrated solu- tion. Potassium nitrate (nitre). Potassium ferrocyanide (yellow prussiate of potash). Sodium chloride (common salt). Acid potassium sulphate (KHSO*) and powdered fluor (CaF). These two reagents serve to expel volatile substances, and to j o Practical Guide to tJte Determination facilitate the recognition of such mineral constituents as colour the flame. Copper oxide (CuO). Manganese dixoide (MnO 2 ). Stannous chloride (protochloride of tin). Ferrous sulphate (green vitriol). Tin-foil. Litmus paper. Turmeric paper. Scale of Hardness. It is often necessary to ascertain the hard- ness of a given specimen. The scale generally employed consists of ten minerals arranged by Mohs, according to their hardness, beginning with the least hard. 1. Graphite, talc. 2. Rock salt, gypsum. 3. Calcite. 4. Fluor. 5. Apatite. 6. Felspar (adularia). 7. Quartz. 8. Topaz. 9. Corundum. 10. Diamond. Small angular sharp-edged fragments of these minerals should be kept always ready for use. In forming the scale it is well to choose specimens as free as possible from impurity, as the presence of a foreign ingredient will often affect, in a noteworthy manner, the hardness of a mineral. The method of using this scale is obvious : the harder substance will scratch the softer, and in the case of two bodies of like hardness neither scratches the other. Practice will soon enable the student to judge pretty accurately the hardness of a specimen by means of a pen-knife alone. Of Minerals by the Blowpipe. \ i REACTIONS- Of the numerous reactions which may be detailed as cha- racteristic of a substance, those only which are simple and easily performed will be described here. Reactions in the dry way are . manifestly the most suitable for our present purpose ; and only when these fail, or are uncertain, will recourse be had to testing in the wet way. Oxygen. This element will only be detected in such sub- stances as can be readily made to part with it in the free state, such substances as will give up their oxygen when heated in a glass tube : the gas is recognised by its rekindling a glowing match. This reaction is often inconclusive, owing to the small size of the fragment under examination. However, another test at once presents itself for these small quantities. The assay is heated in a tube with a fragment of sodium chloride and a few drops of sulphuric acid. Chlorine is now evolved in place of oxygen, and may be recognised by its characteristic odour, or by its bleaching effect on a piece of moist litmus paper. Water. Hydrous minerals when heated in the closed tube evolve aqueous vapour, which is condensed in the cooler parts of the tube. The drops of water thus obtained should be tested with litmus paper; their reaction, whether alkaline, acid, or neutral, is an important characteristic and must be borne in mind. Traces of adventitious water are often detected in weathered or partially weathered minerals. The student must be on his guard against the delusive appearances presented by hygroscopic substances. Sulphur. The presence of this element, whether in sulphides or sulphates, may be detected by fusing the assay with soda on charcoal. The fused mass, when laid on a bright silver surface (any silver coin) and moistened with water, leaves a dark brown stain on the metal. The fused mass on the charcoal, if moistened with a drop of hydrochloric acid, will generally evolve sulphuretted 1 2 Practical Guide to the Determination hydrogen, which may be recognised by its smell or by its black- ening effect on a piece of paper moistened with acetate of lead solution. When the fragment to be tested is very minute, the end of a wooden match will make a very convenient support. The end of the match is smeared with soda and slowly and carefully charred, a little of the moistened assay is affixed to the charcoal point thus obtained, and manipulated as above described (see Charcoal, p. 8). That this test should be conclusive, the absence of selenium and tellurium (which comport themselves similarly) must be proved. When sulphides are heated alone in the flame, the odour of sulphurous acid (SO 2 ) is evolved : sul- phates, when similarly treated, give off no sulphurous acid, and may thus be distinguished from sulphides. Nitrates occur in nature but rarely : they decrepitate on char- coal, and evolve brown-red fumes when fused with acid potassium sulphate. Selenium. This element and its compounds, when heated on charcoal, evolve a strong odour of bad horse-radish. When heated in the glass tube, selenium forms a red sublimate. The oxidizing flame is generally tinged distinctly blue. Tellurium. Tellurium and its compounds yield a white incrus- tation on charcoal; this incrustation disappears in the reducing flame after assuming a green tinge. Tellurium compounds, when heated with concentrated sulphuric acid, colour the liquid red. Phosphorus presents itself for investigation with the blowpipe as a compound of phosphoric acid only. Phosphoric acid imparts to the flame a bluish green tinge. To render this colouration dis- cernible the phosphate should be moistened with sulphuric acid : any water that the mineral may contain must also be eliminated by previous ignition. The colouration by the phosphate may be overpowered by that due to the base with which the phosphoric acid is associated ; or it may only exhibit itself at the commence- ment of the experiment. Bunsen recommends the following 14 Practical Giiide to the Determination of fluorspar. Borates, when moistened with sulphuric acid, impart a distinct colouration to the edge of the flame. When borates are evaporated to dryness with hydrochloric acid in the presence of a slip of turmeric paper, the latter assumes a very characteristic rich red-brown tint. Carbonic Acid. Carbonates are easily recognised by their violent effervescence with acids, e.g., hydrochloric. Sometimes this re- action does not commence till heat is applied. The presence of carbonic acid in small quantity may often be neglected as unim- portant : it is a frequent result of weathering. Silicic Add. Silica or a silicate, when fused in a bead of micro- cosmic salt, yields a skeleton of silica which floats in the bead. Treated with soda in the oxidizing flame, silica and silicates dissolve with effervescence. If the resulting fused mass is treated upon a watch glass, with water and acetic acid (or dilute hydrochloric acid), a gelatinous mass of silicic hydrate separates. If the fused mass while still hot be moistened with chloride of tin and ignited, it will not be coloured blue, distinction between silica and the acids of titanium, niobium, and tantalum. Titanium. Compounds of this element impart to the bead of microcosmic salt a faint amethystine tinge in the reducing flame : the bead becomes colourless in the oxidizing flame. (This titanium colouration is not easily obtained.) The addition of a little ferrous sulphate to the bead in the reducing flame causes it to assume a peculiar blood-red hue. Soda forms with titanium compounds an opaque enamel ; if this while hot be moistened with stannous chloride and ignited in the reducing flame, a mass is obtained which dissolves in warm hydrochloric acid with a faint amethystine colour. Tantalum. The reactions of tantalum are similar to those of titanium. If a tantalum compound be fused with caustic potash and dissolved in hot water, a solution is obtained from which a precipitate falls after neutralization with hydrochloric acid ; if this Of Minerals by the Blowpipe. 1 5 precipitate be boiled with dilute sulphuric acid, it turns pale blue on addition of zinc ; dilution with water at once removes the colour. Niobium. This element comports itself like titanium in the beads. If niobium compounds are subjected to a treatment similar to that described for tantalum, the solution is deeper blue, and becomes first brown and then slowly changes to white on dilution with water. Molybdenum. The borax bead in the oxidizing flame is yellow to dark red while hot, colourless when cold. Molybdenum when present in large quantity makes the bead black. The same bead is brown in the reducing flame. Molybdenum colours the bead of micro- cosmic salt green in both flames. Bunsen gives the following excellent test : The finely powdered assay is fused with soda on platinum wire, the mass so obtained is digested when hot with a couple of drops of warm water, and the supernatant liquid absorbed by filter- ing paper. A small piece of this paper, when moistened with hydro- chloric acid and a drop of potassium ferrocyanide, turns brown-red. A second piece of the paper is moistened with stannous chloride ; this turns blue when warmed. (Should a yellow tint appear in- stead of a blue one, more of the original solution must be added.) The remainder of the paper turns brown on addition of ammo- nium sulphide. Wolfram. In both flames this gives a borax bead varying from colourless to brown. The reactions with the bead of microcosmic salt in the reducing flame, are characteristic ; while hot this bead is dirty green, when cold blue ; the addition of oxide of iron turns it blood-red. According to Bunsen, wolfram compounds may be treated as molybdenum, the paper moistened with hydrochloric acid and potassium ferrocyanide exhibits no colouration ; moistened with stannous chloride it turns blue ; with ammonium sulphide it turns blue or greenish. Vanadium. Compounds of vanadium colour the borax bead yellow in the oxidizing flame, green in the reducing one. 1 6 Practical Guide to the Determination Tin. Compounds of this metal are easily reducible on char- coal with soda. By triturating the fused mass, and washing away the charcoal with water, the metal may be obtained in shining scales. Silver. Silver compounds are readily reduced on charcoal with soda to white ductile beads. The reduced metal is easily soluble in nitric acid ; from the solution hydrochloric acid precipitates white silver chloride. Gold. Like silver, easily reduced. The reduced metal is inso- luble in hydrochloric acid or nitric acid, but soluble in a mixture of the two (aqua regia.) Blotting-paper saturated with this gold solution exhibits a purple colour (purple of Cassius) when moistened with stannous chloride. Platinum. Compounds of this metal when heated on platinum wire in the oxidizing flame furnish a spongy mass, which in the agate mortar may be rubbed into metallic scales. Palladium, Rhodium, Ruthenium, Iridium exhibit no charac- teristic blowpipe reactions. Palladium and rhodium with acid potassium sulphate fuse into a yellow mass. Ruthenium with nitre fuses into an orange-yellow mass. Osmium. Compounds of this metal when subjected to the oxidizing flame, evolve the penetrating odour of volatile osmic acid. Mercury. This eleoawptt is volatilized before the blowpipe. Even small quantities If.: this metal may readily be detected as follows : The dry assay 'is mixed with soda and placed in the closed end of a small glass tube (5 6 millimetres wide and 10 20 millimetres long) ; the open end of the tube is covered with a por- celain dish containing cold water, while the closed end containing the assay is heated : metallic drops or deposit will be obtained. Bismuth. Compounds of this metal yield a yellow incrustation when heated on charcoal. Fused on charcoal with soda, reduction is effected. Very small quantities may be reduced on a charred match. (See Sulphur Tests.) The bismuth bead is brittle, dis. tinction from lead. Of Minerals by the Blowpipe. 1 7 Copper, Borax bead in the oxidizing flame is transparent blue ; in the reducing flame, especially on the addition of tin-foil, liver brown and opaque. Cupriferous minerals yield red metallic scales when fused on charcoal with soda. Lead. Lead compounds colour the flame pale blue, yield a yellow incrustation, and with soda are easily reduced to a soft malleable metallic globule. Cadmium. A brown incrustation on charcoal is characteristic of compounds of this metal. Zinc. On charcoal volatile zinc oxide (lana philosophicd) is readily produced, so that zinc compounds yield an incrustation which is yellow while hot, white when cold. The incrustation ignited with cobalt solution turns green. Cobalt. The borax bead is, in both flames, coloured deep blue by this metal. (See Nickel.) Nickel. In the outer (oxidizing) flame nickel compounds colour the borax bead brown-red, in the inner grey or colourless. Diffi- cultly reduced with soda on charcoal ; if the fused mass be triturated and washed, metallic scales (attracted by the magnet) are obtained. Cobalt acts similarly. Iron. Reduced with soda, ferruginous minerals yield scales powerfully attracted by the magnet. In the oxidizing flame iron colours the borax bead yellow or brownish ; in the reducing flame the bead is colourless or bottle-green. (This change in the inner flame is difficultly obtained.) Manganese. The presence of this metal, even in small quantity, is shown by the amethystine colour it imparts in the oxidizing flame, to the borax bead ; the bead becomes colourless in the reducing flame. Manganese compounds fused with soda and nitre on platinum-foil, yield a green mass, consisting of alkaline manganate. Uranium. In the oxidizing flame the borax bead is yellow, in the reducing flame green. Bunsen's test : Uranium compounds are fused with acid potassium sulphate on platinum wire ; the B 1 8 Practical Guide to the Determination fused mass is then triturated with a fragment of crystallized sodium carbonate and moistened. The solution is absorbed with blotting- paper. This paper, when moistened with acetic acid, exhibits a brown stain on addition of potassium ferrocyanide. Zirconium. Zirconia incandesces, and assumes a dirty violet colour with cobalt solution. Aluminium. Compounds of aluminium exhibit a blue colour when ignited with cobalt solution. Alkalies and iron oxide inter- fere, more or less, with this colouration. Glucinum (beryllium}. Beads of borax and microcosmic salt are clear ; rendered enamel-like by excess of glucina. Yttrium, Lanthanium, Didymium, Thorium, and Cerium furnish no characteristic blowpipe reactions. Chromium colours the beads beautifully green. Fused on plati- num with soda and nitre, chromium compounds yield a bright yellow mass, consisting of alkaline chromates. Magnesium. Minerals of magnesium assume a faint flesh- coloured tint when ignited with cobalt solution : the presence of alkalies, earths, and metallic oxides, interferes more or less with this colouration ; silica does not. Calcium. Calcic compounds colour the flame yellowish red. This colouration is not always readily obtainable, least readily so, with calcic sulphate and silicate. Sulphate should be first ignited on charcoal, and then moistened with hydrochloric acid ; the colouration of the blowpipe flame is thus rendered distinct.* Strontium. Compounds of strontium colour the flame carmine * The flame colourations characteristic of the alkalies, alkaline earths and several other metals, are said to be rendered more distinctly discernible by the employment of pure silver chloride to liberate the volatile compound. Platinum wire cannot l)e used to support the assay, as it forms with silver a fusible alloy and becomes useless. " Iron wire is best fitted for experiments with silver chloride, as from its cheapness, a new piece may be employed for each experiment, whilst the silver may be readily obtained in the form of chloride from the broken pieces." *' Select Methods in Chemical Analysis," by W. Crookes, 1871, page 427. Of Minerals by the Blowpipe. 19 red. Strontium sulphate should be treated as above described for calcium sulphate. Barium and its compounds colour the flame green. Barium sulphate should be treated as calcium sulphate. (See preceding paragraph.) Lithium and its compounds colour the flame red. When sodium is present the red colouration by lithium is only discernible at first. To obtain this flame reaction in the case of a lithium silicate, the substance must be fused with fluorspar and acid potassium sulphate. Sodium. Salts of sodium impart to the flame an intense yellow colour which quite overpowers all other flame reactions, e.g., that of potassium. The colour of paper tinted with mercuric iodide dis- appears in the light of a sodium flame. The sodium flame seen through a cobalt blue glass, appears pure blue, and as the propor- tion of sodium diminishes becomes invisible. Potassium compounds colour the flame violet. Sodium and lithium interfere with this reaction : but if the flame be examined through a plate of cobalt-blue glass, it appears violet. When the presence of potassium, sodium, and lithium is suspected the flame should be examined through a prism filled with solu- tion of indigo. Through a small thickness of indigo solution the sodium flame appears violet, and gradually disappears as the thick- ness of the stratum through which it is seen increases. When the sodium flame disappears the lithium flame appears red, the potas- sium flame blue. As the thickness of the fluid stratum increases the lithium colouration becomes more like that of potassium, which changes from blue to violet, and finally to red. Ammonium. Ammoniacal compounds when heated in the glass tube with soda evolve an unmistakable odour of ammonia ; thick white fumes (NH 4 Cl)are formed when a glass rod moistened with hydrochloric acid is brought near to ammonia cal fumes which are in quantity so small as to remain undetected by their odour. 2o Practical Guide to the Determination The use of the following tables, even without any explanation, will be found to present no difficulty. The most advantageous course to be pursued in the blowpipe determination of any mineral is to perform consecutively the experiments arranged in the general table. As soon as one of these experiments deter- mines the group to which the assay belongs, the operator will proceed to identify the individual by means of one or other of the group tables. These group tables contain reactions sufficient to separate one from another, and to distinguish, the different minerals in the group. All the reactions characteristic of each mineral are given, only, when there is a close resemblance between the members of a group ; for the distinction of minerals which differ considerably among themselves one well-marked peculiarity suffices. One or two preliminary considerations merit the student's attention. The first condition of success consists in the purity of the substance submitted to analysis. The homogeneousness of the assay which is of course essential must be ascertained by examining the fragments with a lens. In a satisfactorily conducted blowpipe analysis the reactions described in the general table are distinct and well marked ; within the groups the analyst must content himself with reactions that are not so clearly defined. Traces of water and carbonic acid are frequently due to incipient weathering, and careful preliminary inspection will be needed to discover whether or not this process has commenced. The chemical composition of a mineral may vary within certain limits. Owing to such variation, which generally results from isomorphism, and is often characteristic of specimens from known localities, the names of many species occur in more than one group of the tables. The magnetic characteristics of minerals under examination Of Minerals by the Bloivpipe. 2 1 are often misleading. Many specimens are attracted by the magnet owing to the presence of iron which may have replaced a constituent isomorphous with it. The iron reaction in Table I., 7, must always be well marked. Dimorphous substances, and those containing the same elements in different proportions, cannot be distinguished by these qualita- tive chemical tests. In such cases recourse must be had to physical properties. The determination of natural silicates presents the greatest difficulties, as a large number of these minerals possess similar properties. The smaller the quantity of material which the analyst submits to his blowpipe tests, the more unmistakable, as a rule, are the reactions, and the more accurate the results. 22 Practical Guide to the Determination GENERAL TABLE. I. The mineral powder is heated on charcoal before the blowpipe. 1. // is volatilized or burned. 2. Odour of garlic is evolved. a. Minerals with metallic lustre. b. Minerals without metallic lustre. 3. Odour of horse-radish is evolved. 4. Fumes of antimony are evolved. a. Minerals with metallic lustre. a. Reduced with soda on charcoal bead of lead. /3. Reduced with soda on charcoal bead of silver. y. Fused with soda on charcoal neither lead nor silver. b. Minerals without metallic lustre. 5. A white incrustation on the charcoal, colouring the reducing flame green. (The mineral powder heated with concentrated sulphuric acid yields a red liquid). a. Mineral is tin-white. b. Mineral is lead-grey or steel-grey. 6. Residue after ignition shows an alkaline reaction. a. Easily soluble in water. a. Evolve water when heated in the glass tube. /3. Do not evolve water when heated in the glass tube. b. Insoluble, or very difficultly soluble, in water. a. Mineral powder effervesces with hydrochloric acid. Of Minerals by the Blowpipe. 23 /5. Sulphur reaction when fused with soda, y. Mineral does not effervesce with hydrochloric acid, nor exhibit the sulphur reaction when . fused with soda. 7. Residue after ignition is magnetic. a. Minerals with metallic lustre. b. Minerals without metallic lustre. II. The substance, mixed with soda, is exposed on charcoal to the reducing flame. 1. The fused mass exhibits the sulphur reaction with silver, and yields a metallic bead. a. Anhydrous minerals. b. Hydrous minerals. 2. The fused mass exhibits the sulphur reaction, but yields no metallic bead. a. Hydrous minerals. b. Anhydrous minerals. 3. The fused mass yields a metallic bead, but does not exhibit the sulphur reaction. a. The bead is bismuth. b. The bead is lead. c. The bead is silver. d. The bead is copper. e. The bead consists of some other metal. III. The borax bead is amethystine in the outer flame. 1. Minerals with metallic lustre. 2. Minerals without metallic lustre. IV. The mineral powder assumes a green colour when ignited with cobalt solution. 24 Practical Guide to the Determination V. Minerals entirely soluble in hydrochloric acid. 1 . Fusible before the blowpipe. a. Water evolved on heating in the closed tube (hydrous minerals). b. No water evolved on heating in the closed tube (An- hydrous minerals). 2. Infusible before the blowpipe. a. Hydrous minerals. b. Anhydrous minerals. VI. Soluble in (decomposed by) hydrochloric acid, leaving a jelly of silica. 1. Fusible before the blowpipe. a. Hydrous minerals. b. Anhydrous minerals. 2. Infusible before the blowpipe. a. Hydrous minerals. b. Anhydrous minerals. VII. Soluble in hydrochloric acid, with separation of silica, without the formation of a jelly. 1. Hydrous minerals. 2. Anhydrous minerals. VIII. Insoluble in hydrochloric acid ; Skeleton of silica left in the bead of microcosmic salt. 1. Fusible before the blowpipe. 2. Infusible before the blowpipe. IX. Minerals which are not comprehended within any foregoing group. Of Minerals by the Blowpipe. 25 I. The mineral powder is heated on charcoal before the blowpipe. 1. It is volatilized or burned. Native Sulphur. Native Arsenic. Native Selenium. Native Tellurium (Sylvanite). Native Antimony. Selenschwefel. Realgar AsS 2 . Orpiment, AsS 3 . Arsenic Bloom, AsO 3 . Antimony Bloom, SbO 3 . Senarmontite, SbO 3 . Antimony Blende, (Rothspiess- glanzerz), SbO 3 + 2SbS 3 . Antimony Ochre, SbO 5 +*HO. Stiblite, SbO 3 ,SbO 5 . Antimonite SbS 3 . Sal-ammoniac, NH 4 C1. Mascaganine, NH 4 O,SO 3 2HO. + Cinnabar, HgS. Calomel, (Quecksilberhornerz) Hg 2 Cl. Sylvine (Hovelite, Leopoldite), KC1. Chloride of lead (Cotunnite), PbCl. Clausthalite (Selenqueck- silber), Hg Se. Graphite, C. The following, when heated on charcoal, evolve an odour of arsenic : Native arsenic : volatilizes without fusion : in closed glass tube dark grey metallic sublimate : in platinum forceps colours the flame bluish : lustre metallic : tin white : surface dulled or blackened. Arsenic bloom: sublimes, without fusion, to small white crystals : in the forceps colours the flame blue : soluble in hot water : lustre vitreous. The following, when heated on charcoal, evolve an odour of sulphurous acid : Sulphur : burns with blue flame : melts in the glass tube and volatilizes : H=i*5 : brittle. Cinnabar: volatilizes in closed glass tube, yielding a black sublimate : heated in a closed tube with soda or potassium cyanide, yields a metallic mirror of drops of mercury: red: H=2*5. The following, when heated on charcoal, evolve the odour of arsenic and of sulphurous acid : Realgar : when heated in the closed tube, swells up and furnishes a translucent red sublimate : red, turning brown on addition of potash. Orpiment: swells up when heated in the closed tube, and furnishes a dark yellow sublimate : yellow : soluble in potash. 26 Practical Guide to the Determination The following, when heated on charcoal, evolve fumes of antimony : Native antimony \ fuses into a bead which, when cold, is covered with white crystals of oxide of antimony : opaque : lustre metallic : tin white. Antimony bloom : translucent : lustrenacreous : white : sublimes in closed tube. Senarmontite : rather harder than antimony bloom, from which it can only be distinguished by its crystallographic form. Antimony blende effervesces before the blowpipe, and yields a bead of antimony : evolves water in, the closed tube: H=i.5. Stiblite: furnishes a bead of antimony before the blowpipe on charcoal : evolves no water in the closed tube. The following, when heated on charcoal evolve antimonial fumes and odour of sulphurous acid: Antimony blende: in the closed tube first a white, and then an orange yellow sublimate, lustre adamantine : streak cherry red : H = i*5. Antimonite: easily fusible in the closed tube, yielding, when strongly heated, a brown sublimate: lustre metallic: lead-grey: H=2. The following, when heated on charcoal, evolve an odour of horse-radish : Native Selenium and Seknide of Mercury : selenide of mercury gives a metallic mirror of mercuric drops when heated with soda in the closed tube. Sulphide of Selenium : evolves a smell of horse-radish and the odour of sulphurous acid. Native Tellurium : fuses easily, and burns with a greenish flame : tin white : lustre metallic. Sal-ammoniac : volatilizes without fusion : easily soluble in water : warmed with potash evolves ammoniacal fumes. Mascagnine : fuses before the blowpipe : effervesces, and is then volatilized : yields water in the closed tube : sulphur reaction with soda. Sylvine : fuses and is then volatilized, imparting a faint violet colour to the flame : soluble in water. C&tunnite: when heated on charcoal, yields a yellowish green Of Minerals by the Blowpipe. 27 incrustation : reduced with soda to a metallic (malleable) bead : difficultly soluble in water. Calomel: yields drops of mercury when heated with soda in the closed tube : lustre adamantine : greyish white : insoluble in water. Graphite: mixed with nitre, burns with production of carbonic acid : before the blowpipe on charcoal burns slowly, leaving an ash behind. a. Minerals with metallic lustre. rtsE 2. Odour of garlic is evolved. *-* R S I Native Arsenic. Dufrenoysite (Binnite), 2Cu 2 S, AsS 2 + 2CuS,AsS 2 . Arsenical Antimony. Skliiroklas (Sartorite) 2PbS,AsS 3 . Fahlerz 4RS,^|s 3 . Polybasite, 9(Ag,Ca)S,^| S 3 . Smaltine, (Speissko- balt) CoAs 2 . Arseneisen (Leucopyrite), FeAs 2 . Cobaltine (Glanz- kobalt), CoS 2 + CoAs 2 . Kupfernickel, NiAs. Weissnickelkies (Rammelsbergite), NiAs 2 . Nickelglanz, NiS 2 -f NiAs 2 . Mispickel, FeS 2 + FeAs. Schulzite (Geokronite), 5PbS,(SbAs)S 3 . Native Bismuth, owing to arsenical impurity. Native Arsenic and Arsenical Antimony are only found in this group when the mineral tested is impure, or when too large a portion of it is taken ; in either of these cases the complete volatility of the mineral is not readily apparent. a. The following, when heated with hydrochloric acid, evolve sulphuretted hydrogen : Dufrenoysite gives the copper reaction with the borax bead ; fuses readily before the blowpipe, evolving fumes of arsenic and sulphurous acid, and leaves metallic copper. Fahlerz evolves fumes of antimony before the blowpipe, often colours the borax bead with copper, swells up, and fuses to a slag : many specimens yield an incrustation of zinc on charcoal. Cobaltine colours the borax bead blue, and fuses before the blow- pipe on charcoal to a magnetic bead. Nickelglanz decrepitates 23 Practical Guide to the Determination before the blowpipe, and gives a red-brown colour to the borax bead in the oxidizing flame. Mispickel fuses before the blowpipe into a magnetic bead ; borax bead green in the inner flame, brown in the outer one. The following, when fused with soda ou charcoal, yield metallic lead : Sklaroklas : very brittle : 11 = 2-5. Schulzite yields an anti- mony incrustation and antimony fumes ; fuses readily, and some- times gives a feeble copper reaction. Polybasite yields a globule of silver when fused with soda on charcoal ; always gives an antimony incrustation ; fuses on charcoal into a dark grey metallic bead. ft. The following, when heated with hydrochloric acid, do not evolve sulphuretted hydrogen : Smaltine furnishes a blue borax bead ; fuses before the blowpipe into a dark grey, magnetic, and very brittle bead. Arseneisen yields before the blowpipe a black magnetic mass ; streak greyish black. Kupfernickel imparts, in the outer flame, a brown-red colouration to the borax bead ; fuses before the blowpipe into a magnetic globule : lustre metallic, copper-red, streak brownish black. Weissnickelkies, similar in reaction to kupfernickel, fuses readily before the blowpipe, and incandesces for some time after removal from the flame ; tin white ; streak grey. b. Minerals without metallic lustre. K6ttigite3(ZnO,CoO,NiO)AsO 5 + 8HO. Scorodite FeO,AsO 5 + 4HO. Symplesite 3FeO, AsO 5 + 8HO. Eisensinter3Fe 2 O 3 ,3 + 15HO.Wurfelerz(Pharmacosiderite)3FeO,AsO 5 + 3Fe 2 O 3 ,2AsO 3 + 18HO Pharmacolite 2CaO,AsO 5 + 6HO. Chrondrarsenite 5MnO,AsO 5 + 5HO. Cobalt Bloom (Erythrine) 3CoO,AsO 5 + 8HO. Nickelbluthe (Annabergite) 3NiO,AsO 5 + 8HO. Roth- Q1 ~V giiltigerz (Pyrargyrite and Proustite) 3AgS + As f S 3 . Erinite Of Minerals by the Bloivpipe* 29 5CuO,AsO 5 + 2HO Chalk ophyllite (Tamarite) 3CuO,AsO 5 + 9HO + 3(CuO,HO). Liroconite2CuO,AsO 5 + 2A1 2 O S , AsO 5 3 + 2HO. Euchroite 3CuO,AsO 5 -- 6HO + CuO,HO. Olivenite 3CuO, S O & + CuOHO. Kupferschaum (Tyrolite) 5CuO, AsO 5 10 + HO + CaO,C0 2 . The following minerals give the copper reaction with the borax bead ; or when moistened with hydrochloric acid, tinge the flame blue : Erinite, heated before the blowpipe on charcoal, yields a copper bead, enveloped in a brittle slag ; heated in the closed tube yields water; H=4'5 5; translucent on the edges, cleavage surfaces show a waxy lustre. Chalkophyllite decrepitates violently before the blowpipe, and fuses into a brittle metallic globule, emerald green; H = 2 ; streak light green. Kupferschaum decre- pitates before the blowpipe, turns black, and fuses into a steel- grey bead ; on charcoal fuses into a slag ; H = i 1*5 ; apple-green ; streak verdigris green ; effervesces with acids. Euchroite is re- duced before the blowpipe, first to white arsenide of copper, and then to metallic copper; H = 3'5 ; translucent: lustre vitreous. Liroconite does not decrepitate, swells up and melts on charcoal to a brown slag; when slightly heated turns blue. Olivenite melts in the forceps before the blowpipe ; on cooling crystallizes into a black radiated mass ; yields little water in the tube ; on charcoal furnishes a brown slag ; streak olive-green to brown. Kottigite yields before the blowpipe an incrustation of zinc oxide, and the green colouration with cobalt solution. Cobalt bloom gives a blue colour to the borax bead ; peach- coloured. Nickelbliithe in the outer blowpipe flame gives a brown-red borax bead ; yellowish green. Rothgultigerz yields metallic silver when fused on charcoal with ' soda ; and before the blowpipe evolves antimony fumes. Chondrarsenite colours the borax bead violet in the outer flame. 30 Practical Guide to the Determination The following become magnetic when heated on charcoal before the blowpipe : Scorodite fuses readily, forming a slag ; H = 3'5 4; streak greenish white. Symplesite, infusible; H = 5; streak pale indigo blue to white. Eisensinter fuses before the blowpipe ; on addition of water becomes red, transparent, and falls to pieces ; H=2'5 ; streak yellow. Wiirfelerz fuses before the blowpipe ; in the tube yields water, turns red, and intumesces ; streak yellow. Pharmacolite melts before the blowpipe on charcoal into an opaque bead ; colours the flame feebly yellow-red, and generally imparts to the borax bead the blue colouration of cobalt. 3. Odour of horse-radish is evolved. Selenide of Lead, PbSe. Selenide of Copper, Cu 2 Se. Selenide of Mercury, HgSe. Selenide of Silver, AgSe. Selenide of Lead and Copper, CuSe-f PbSe. Selenide of lead, when fused on charcoal with soda, furnishes metallic lead ; decrepitates before the blowpipe ; emits fumes of selenium before the blowpipe on charcoal, .and furnishes on the latter a red, yellow, and white deposit. Selenide of copper colours the borax bead blue green in the outer flame, and brown in the inner ; melts before the blowpipe on charcoal into a grey malleable bead. Selenide of mercury, when heated with soda in a tube, gives off drops of mercury ; brittle; Hzz2'5. Selenide of silver yields metallic silver when fused on charcoal with soda ; on charcoal melts quietly in the outer flame ; in the ftiner flame froths up during fusion, and incandesces during cooling. Selenide of lead and copper fuses very readily before the blow- pipe, runs on the charcoal, and forms a grey mass with metallic lustre ; colours the borax bead blue ; and yields metallic lead when fused with soda on charcoal. Of Minerals by the Blowpipe. 3 r 4. Fumes of antimony are evolved. a. Minerals with metallic lustre. a. Reduced with soda on charcoal : bead of lead. Zinkenite, PbS,SbS 3 . Jamesonite, 3PbS,2SbS 3 . Plagionite, 4PbS + 3SbS 3 . Schulzite (Geokronite), 5PbS,SbS 3 . Bournonite, 3Cu 2 S,SbS 3 + 2(3PbS,SbS 3 ). Fahlerz, 4(Cu,Ag,Pb &c.)S,SbS 3 . Freieslebenite (Schilfglaserz) 3(Ag,Pb)S,SbS 3 . Kobellite, 3(4PbS + FeS) + (4BiS 3 + SbS 3 .) The following exhibit a copper reaction: Bournonite yields a dark red sublimate containing sulphur, when heated in the closed glass tube ; it readily fuses before the blowpipe, and forms a slaggy mass; brittle; H=2'5; streak dark grey. Fahlerz decrepi- tates before the blowpipe ; melts easily on charcoal with ebullition into a grey slag ; H=3 4. Zinkenite decrepitates before the blowpipe and fuses easily, H=3'5- Plagionite, brittle, decrepitates before the blowpipe; H=2'5. Jamesonite, Boulangerite, Schulzite, Kilbrickenite, only differ quantitatively from Plagionite. Kobellite colours the borax bead brown in the outer flame; the lead bead reduced from Kobellite is brittle on account of the bismuth it contains. Freieslebenite-. The lead bead reduced from this mineral is argentiferous ; the presence of silver is most easily shown by the wet way. /3. Reduced with soda on charcoal : bead of silver. Antimonsilber, Ag 2 Sb. Miargyrite, AgS,SbS 3 . Fahlerz. Ste- phanite. (Melanglanz), 6AgS,SbS3. Rothgiiltigerz (Pyrargyrite), 3AgS,SbS 3 . Polybasite, 9(Ag,Cu,&c.)S,SbS 3 . The following evolve an odour of sulphurous acid when heated before the blowpipe : Polybasite colours the borax bead blue with 32 Practical Guide to the Determination copper, decrepitates and melts readily before the blowpipe; H= 2-5 ; Sp. Gr. = 6*5. Fahlerz shows the copper reaction with the borax bead ; decrepitates before the blowpipe and fuses readily ; contains a small amount of silver, and generally zinc and iron ; H=3 4 ; Sp. Gr.=4'5. Miargyrite Hn2'5 sectile ; iron-black to steel-grey, streak light red. Stephanite, H=2'5 ; black ; streak black. Antimonsilber, when heated, evolves no odour of sulphurous acid ; fuses readily before the blowpipe. y. Fused with soda on charcoal : neither lead nor silver. Native Antimony. Ullmannite (Nickelantimonglanz), NiS 2 + NiSb. Antimonite (Antimonglanz), SbS 3 . Breithauptite (Antimon- nickel) Ni 2 Sb. Wolfsbergite (Kupferantimonglanz), Cu 2 S + SbS 3 . Completely volatilized after considerable time: Native Anti- mony and Antimonite (See I. i.) The following exhibit the sulphur reaction (see page 1 1 ) : Ullmannite in the outer flame colours the borax bead brown-red ; H= 5 ; brittle ; streak grey. Wolfsbergite imparts the copper coloura- tion to the borax bead ; decrepitates before the blowpipe ; and melts easily ; H=3*5 ; colour lead-grey to iron-black ; streak black. Breithauptite exhibits no sulphur reaction ; borax bead coloured by nickel ; very difficultly fusible ; H=5 ; streak red-brown. b. Minerals ivithout metallic lustre. Stiblite, SbO 3 SbO 5 . Antimonocher, SbO 5 + JcHO. Anti- mony Blende (Kermes), SbO 3 2SbS 3 , Heteromorphite, 2PbS,SbS 3 . Boulangerite, 3PbS,SbS 3 . Rothgultigerz, 3AgS,SbS 3 , Romeite, 4CaO,5SbO 5 . The following exhibit the sulphur reaction : Antimony blende, easily fusible before the blowpipe, colouring the flame pale green ; H = i - 5 ; lustre adamantine; cherry-red to brown-red ; streak red to brown. Heteromorphite yields metallic lead when fused with soda on charcoal ; melts readily before the blowpipe; H=2; grey; Of Minerals by the Blowpipe. 33 streak dark grey with metallic lustre. Boulangerite furnishes metallic lead when fused with soda on charcoal ; H=3. Roth- giiltigerz when fused with soda in the reducing flame, yields metallic silver ; decrepitates before the blowpipe ; and melts into a black bead ; streak red. Stiblite is not reduced on charcoal alone, but forms a white incrustation; fused with soda, yields a bead of metallic antimony ; yellow; H = 5-5. Antimonocher froths up on charcoal before the blowpipe, and is reduced ; gives off water in the glass tube ; yellow ; H = i. Romeite fuses before the blowpipe into a blackish slag ; yields a bead of antimony by reduction with soda ; hyacinth-red to honey-yellow ; H = 6 7. 5. A white incrustation on the charcoal, colouring the re- ducing flame green. (The mineral powder heated with sulphuric acid yields a red liquid.) a. Mineral is tin white. Native Tellurium. Petzite (Tellursilber) AgTe. Altaite (Tel- lurblei), PbTe. Native Tellurium melts easily before the blowpipe ; generally evolves an odour of selenium ; volatilizes almost entirely ; H = 2. Petzite yields metallic silver by reduction with soda ; H = 2-5 malleable. Altaite gives a bead of lead when reduced with soda, fuses easily before the blowpipe, forming a yellow incrustation. b. Mineral is lead-grey or steel-grey. Tetradymite (Tellurwismuth), BiS 3 + 2BiTe 3 . Sylvanite (Schrif- terz), (Au,Ag)Te 2 . Blattererz (Nagyagite), PbTe, (with PbS and AuTe 2 ). The following exhibit the sulphur reaction : Tetradymite yields with soda in the reducing flame a brittle globule of bismuth : 34 Practical Guide to the Determination generally evolves an odour of selenium ; streak black. Bldttererz with soda in the reducing flame yields a malleable metallic bead of lead; streak lead-grey. Sylvanite exhibits no sulphur reaction ; fuses before the blow- pipe into a grey metallic bead ; by long-continued blowing a yellow malleable bead is obtained. 6. Residue after ignition shows an alkaline reaction. a. Easily soluble in water. a Evolve water when heated in the glass tube. Mirabilite, (Glaubersalz) NaO,SO 3 + 10HO. Thermonatrite, NaO,CO 2 + HO. Soda, NaO,CO 2 + 10HO. Trona, 2NaO,3CO 2 + 4HO. Epsomite (Bittersalz), MgO,SO 3 + 7HO. Potassium Alum, KO,SO 3 + A1 2 O 3 3SO 3 + 24HO. Sodium Alum NaO,SO 3 + A1 2 O 3 3SO 3 + 24HO. Ammonium Alum, AmO,SO 2 + A1 2 O 3 ,3SO 3 + 24HO. TinkalNaO,2BO 3 +10HO. Loweite, (2MgO,SO a + NaO 2SO 3 ) + 5HO. Carnallite, KC1 + MgCl + 12HO. Boussingaul- tite (Am,Mg,Fe)O,SO 3 + HO. Kainite MgO,SO 3 + KCl-t-6HO. The following effervesce with hydrochloric acid : Trona H = 2-5; specific gravity = 1*4; fuses readily in the glass tube, and evolves much water. Soda ; H = i 1*5; Sp.Gr. = 1*4 ; fuses in the tube with liberation of much water ; weathers speedily when exposed to the air. Thermonatrite does not fuse, and yields much less water than the preceding. The following exhibit the sulphur reaction when fused with soda : The alums show a blue colour when strongly ignited with cobalt solution. Potassium alum, H = 2^5 ; fuses and swells up before the blowpipe, colours the flame feebly violet. Sodium alum, H = 2 *5 ; fuses and swells up before the blowpipe ; imparts, especially if moistened with hydrochloric acid, a distinct yellow colouration to the flame. Ammonium alum, when warmed with potash, evolves an ammoniacal odour ; before the blowpipe fuses and swells up. Epsomite, after ignition, exhibits a flesh-red Of Minerals by the Blowpipe. 35 colour with cobalt solution ; H = 2 2*5 ; fuses before the blow- pipe with intumescence. Mirabilite: cobalt solution produces no effect ; H = 1-5 ; fuses very easily; is absorbed by the charcoal ; colours the flame distinctly yellow. Low cite : H = 2-5 3 ; small- fragments fly to pieces when heated in the glass tube, lose their water, and then melt tranquilly. Boussingaultitc evolves, with potash, the smell of ammonia ; contains little water. Kainite exhibits a flesh colour when ignited with cobalt solution ; imparts a violet colouration to the blowpipe flame, its solution yields a precipitate with nitrate of silver. Tinkal intumesces before the blowpipe and then melts : imparts to the flame a transient green tint : lustre resinous. Carnallite deliquescent : fuses easily, and colours the flame feebly violet : H=2 2' 5 : yields a faint white sublimate on charcoal. /3. Do not evolve water when heated in the glass tube. Nitre (Kalisalpeter), KO,NO 5 . Nitratine (Natronsalpeter), NaO,NO 5 . Nitrocalcite (Kalksalpeter), CaO,NO 5 . Glaserite, KO,SO 3 . Thenardite, NaO,SO 3 . Rock salt, Nad. The following decrepitate when heated on charcoal : Nitre colours the flame violet. Nitratine colours the flame yellow. Nitrocalcite colours the flame yellowish red, and decrepitates but feebly. The following exhibit the sulphur reaction with soda : Glaserite decrepitates and fuses before the blowpipe : imparts a feeble potassium colouration to the flame. Thenardite fuses at a higher temperature, and then colours the flame yellow. Rock salt : characteristic salt taste : fuses easily, and colours the flame yellow: H = 2. b. Insoluble^ or very difficultly soluble in water. a. Mineral powder effervesces with hydrochloric acid. Witherite, BaO,CO 2 . Calcite, CaO,CO 2 . Aragonite, CaO,CO 2 . Strontianite, SrO,CO 2 . Gaylussite, CaO,CO 2 + NaO,CO 2 + 5HO. 36 Practical Guide to the Determination Dolomite (Bitterspar),CaO,CO 2 + MgO,CO 2 . Magnesite : MgO,CO 2 . Barytocalcite, BaO,CO 2 4- CaO,CO 2 . Alstonite, BaO,C(X - 1 - CaO,CO 2 . Nemalite MgO,CO 2 + 6HO*. Hydromagnesite 4MgO,3CO 2 + 4HO. The following evolve water when heated in the glass tube. Gay- lussite colours the flame yellow : brittle : decrepitates : melts to an opaque head. Hydromagnesite : no flame reaction : infusible : ignited with cobalt solution yields a flesh-coloured mass : Hr=3 : dull. Nemalite; no flame reaction : infusible : assumes a flesh- coloured tint when heated with cobalt solution, H=2 : lustre silky. The following impart a green colour to the flame when moistened with hydrochloric acid : Witherite: fuses easily to a bead of white enamel. Barytocalcite: colours the flame yellow green : before the blowpipe becomes white and opaque, and coated with a greenish glass. Alstonite comports itself as barytocalcite, but most speci- mens also exhibit, after a short time, the red flame of strontium. Strontianite, when moistened with hydrochloric acid, colours the flame a fine crimson red. The following, when moistened with hydrochloric acid, colour the flame yellow-red: Calcite : H= 3 : glows, but does not melt before the blowpipe. Aragonite : 11=3.5 4 : before the blow- pipe remains white and infusible : swells up when heated in the glass tube, and falls into a light powder. Dolomite: H = 3'5 : larger fragments effervesce but slowly when heated with hydro- chloric acid : the powder remains incoherent when heated on platinum-foil \ under like circumstances calcic carbonate cakes together. Magnesite gives no flame reaction : H=4 4-5 : infusible : with cobalt solution turns flesh-red. (3. Sulphur reaction when fused with soda. Anhydrite (Karstenite), CaO,SO 3 . Gypsum, CaO,SO 3 + 2HO. Heavy spar (Baryte), BaO,SO 3 . Celestine, SrO,SO 3 . Polyhalite, * Some mineralogists consider this an altered Brucite. Of Minerals by the Blowpipe. 37 KO,SO 3 + MgO,SO 3 + 2(CaO,SO 3 ) + 2HO. Brogniartin, CaO,SO 3 + NaO,SO 3 . Alunite (Alumstone), KO,S0 3 + (3A1 2 O 3 ,SO 3 ) + 6HO. Kieserite, MgO,SO 3 + 3HO. Websterite (Aluminite), A1 2 O 3 ,SO 3 + OHO Keramohalite, A1 2 O 3 ,3SO 3 + 18HO. The following evolve water when heated in the glass tube : Gypsum : before the blowpipe turns opaque white : exfoliates with decrepitation, and melts into a white enamel: H=2 : gives off much water in the tube. Poly halite: yields little water: melts easily before the blowpipe to a brown-red bead : soluble in water with slight residue : 11=3-5. Websterite infusible : friable : com- portment of Alunite is similar to that of Websterite (see Formula). Keramohalite intumesces before the blowpipe, and is then infusible H = 2. Kieserite is difficultly soluble in water. Celestine, when moistened with hydrochloric acid and ignited, colours the flame intensely red (crimson) : decrepitates and melts to an enamel. Heavy spar, when moistened with hydrochloric acid and ignited, colours the flame green : decrepitates violently, and melts difficultly into an enamel. Anhydrite, moistened with hydrochloric acid and ignited, colours the flame yellow red : decrepitates feebly and melts into a white enamel. Brogniartin moistened with hydrochloric acid and ignited colours the flame yellow : has a faintly salt taste : is partly soluble in water : decrepitates before the blowpipe. y. The mineral does not effervesce with hydrochloric acid ; nor exhibit the sulphur reaction when fused with soda. Borocalcite, CaO,2BO 3 + 6HO. Pharmacolite, 2CaO,AsO 5 + 6HO. Haidingerite, 2CaO,AsO 5 + 4HO. Brucite, MgO,HO. Boracite, 2(3MgO,4BO 3 ) + MgCl. Fluor, CaF. Cryolite, 3NaF + A1 2 F 3 . Chiolite,3NaF + 2Al 2 F 3 . Natrolite(Mesotype),NaO,2HO + Al 2 O 3 3SiO 2 . Spinelle, MgO,Al 2 O 3 . Talc may occur here. (See VIII. 2). 38 Practical Guide to the Determination The following impart to the flame a feeble green colouration of boracic acid : Borocaldte^ after the volatilization of the boracic acid, tinges the flame yellow-red with calcium : evolves water in the glass tube. Boracite melts before the blowpipe with intumes- cence to a bead, on the surface of which, as it cools, crystalline particles are formed : H = 7. The following evolve an odour of garlic when heated on char- coal : Pharmacolite fuses to a white enamel. Haidingerite is similar to pharmacolite, but yields less water: pharmacolite is generally coloured by cobalt, and exhibits the corresponding reaction with the borax bead. Brucite is infusible before the blowpipe, but becomes white and opaque: lustre nacreous ; H= 1-5: assumes a flesh-coloured tint when ignited with cobalt solution. Spinelle: H = 8: turns blue when heated with cobalt solution. The following, when heated with sulphuric acid, evolve hydro- fluoric acid: Cryolite decrepitates slightly, and melts on the charcoal before the blowpipe to a clear globule, which on cooling is coated with a white enamel : colours the flame yellow : H = 2-5. Chiolite exhibits the same reactions as Cryolite : H = 4. Fluor decrepitates before the blowpipe, and fuses into an opaque bead : colours the flame red : H == 4. Natrolite furnishes a skeleton of silica in the microcosmic bead : splinters of it become opaque when heated, and again clear at a higher temperature : H = 5-5. 7. Residue after ignition is magnetic. a. Minerals with metallic lustre. Hematite (Eisenglanz), Fe 2 O 3 . Magnetite (Magneteisen), FeO,Fe 2 O 3 : Ilmenite (Titaneisen, probably sesquioxide of iron and titanium). Limnite, (Brown Hematite, Brauneisenstein), Fe 2 O 3 ,3HO. Chromite (Chromeisenstein), FeO,Cr 2 O 3 . Wolfram (FeO,MnO),WO 3 . Franklinite, (FeO,MnO,ZnO),(Fe 2 O 3 ,Mn 2 O 3 ).* * Magnetic iron pyrites and pyrite, sometimes occur here. Cu 8 S, owing to impurity, sometimes occurs here. Of Minerals by the Blowpipe. 39 Limnite {Brown Hematite), when heated in the closed tube, evolves water: dull brown : H = 5*5 : streak yellowish brown. Hematite : anhydrous : infusible : H = 6 : streak red. Magnetite is magnetic even before ignition : H = 6 : streak black. Chromite colours the borax bead green : H = 5-5 : streak brown. Ilmenite colours the bead of microcosmic salt violet in the reducing flame : streak black : H = 5 6. Wolfram gives a blood red bead with microcosmic salt in the reducing flame : fused with nitre and soda on platinum-foil, gives a green mass : streak reddish-brown to black: H = 5*5. Franklinite yields the zinc incrustation on charcoal before the blowpipe : exhibits the manganese reaction : streak reddish-brown : H = 6 - 6-5. b. Minerals without metallic lustre. Spathose iron (Chalybite), FeO,CO 2 . Brown Hematite (Braun- eisenstein Fe 2 O 3 ,3HO. Gothite (Nadeleisenstein), Fe 2 O 3 ,HO. Rotheisenstein (Eisenocker), Fe 2 O 3 . Botryogen * 3FeO,2SO 3 + 3Fe 2 O 3 ,2SO a + 36HO. Voltaite (FeO,KO)SO 3 + 2(Fe 2 O 3 ,3SO3) + 12HO. Copiapite, 2(Fe 2 O 3 ,2SO 3 )-f 21HO. Misy, 2Fe 2 O 3 ,5SO 3 + 6HO. Nontronite, Fe 2 O 3 ,2SiO 2 -f 3HO. Coquimbite, Fe 2 O 3 ,3SO 3 + 9HO. The following evolve water when heated in the closed tube : Brown hematite^ $.$ : lustre adamantine or vitreous : streak yellowish brown. Gothite yields less water than brown hematite : 11=4-5: brittle; translucent in thin splinters, streak yellowish brown. Botryogen swells up when heated before the blowpipe : exhibits the sulphur reaction : translucent : lustre vitreous : streak ochrepus yellow. Voltaite yields an earthy mass when heated before the blowpipe: exhibits the sulphur reaction : dissolves with difficulty * Decomposition product chemical composition doubtful. The like remark applies to several minerals in this group. 4O Practical, Guide to the Determination in water : streak greyish green : opaque : black. CoquimUte exhibits the sulphur reaction : white, blue, green : streak white. Copiapite exhibits the sulphur reaction : translucent : yellow : lustre nacreous. Misy is similar to copiapite, but contains less water. Nontronite exhibits no sulphur reaction : heated in the microcosmic bead, silica separates : dull straw yellow : greasy to the touch : turns red before the blowpipe. Spathose iron dissolves with effervescence in warm nitric acid ; imparts the iron colouration to borax beads : generally contains manganese. Rotheisenstein is but an ochreous variety of hematite. II. The substance mixed with soda is exposed on charcoal to the reducing flame, 1. The fused mass exhibits the sulphur reaction with silver, and yields a metallic bead. a. Anhydrous minerals. Bismuthine, BiS 3 . Tetradymite, BiS 3 + 2BiTe 3 . Galena (Bleiglanz), PbS. Anglesite (Bleivitriol), PbO,SO 3 . Bismuthite, BiO 3 ,CO 2 + BiO 3 ,SO 3 . Leadhillite, PbO,SO 3 + 3(PbO,CO 2 ). Lanarkite, PbO,SO 3 + PbO,CO 2 . Nadelerz (Patrinite), 3Cu 2 S,BiS 3 + 2(3PbS,BiS 3 ). Millerite, NiS. Linneite, Co 2 S 3 . Argen- tite, AgS. Cuproplumbite, 2PbS + Cu 2 S. Stromeyerite, Cu 2 S + AgS. Stannine (Zinnkies), 2FeS,SnS 2 + 2Cu 2 S,SnS 2 . Redruthite, Cu 2 S- Covelline, CuS. Buntkupfererz (Bornite), 3Cu 2 S,Fe 2 S 3 . Copper Pyrites (Towanite), Cu 2 S,FeS s . Eisennickelkies, 2FeS + NiS. Carmenite, Cu 2 S + CuS. Rahtite, Cu 2 S -f ZnS.* The metallic bead obtained by reduction with soda consists of bismuth. Bismuthite effervesces with hydrochloric acid : H = 3'5 : lustre vitreous, or dull : greenish or yellowish : streak white. Tetradymite exhibits the tellurium reaction ; and generally evolves the odour of selenium : lustre metallic : silver white : streak black : * Probably a mixture of blende and other minerals. Of Minerals by the Blowpipe. 41 H=i'5. Bismuthine fuses easily before the blowpipe, with effer- vescence: H=2'5: lustre metallic: steel grey to brass yellow: streak the same. Nadelerz exhibits the copper reaction : H=2'5 . lustre metallic : steel grey : streak dark grey. The metallic bead obtained by reduction with soda consists of lead. Galena decrepitates when heated in the test tube, and fur- nishes a sublimate of sulphur : lustre metallic : lead grey : H = 2 : streak dark grey. Anglesite decrepitates before the blowpipe: lustre adamantine to resinous: H=3: white, grey, brownish: streak grey. Leadhillite intumesces when heated before the blow- pipe and turns yellow, and on cooling becomes white again: easily reduced to metallic lead : effervesces with hydrochloric acid: H=2'5 : translucent: yellowish: streak white. Lanarkite melts before the blowpipe to a white bead ; effervesces feebly with hydrochloric acid: H=2 : transparent: greenish white: streak white. Cuproplumbite exhibits the copper reaction : the reduced metallic bead is not so malleable as the others : fuses before the blowpipe with ebullition : lead grey : streak black. The metallic bead obtained by reduction with soda consists of nickel. Millerite fuses before the blowpipe into a magnetic mass: lustre metallic : yellow. Eisennickelkies gives a well-marked iron reaction : H=4 : lustre metallic : pinchbeck brown. The metallic bead obtained by reduction with soda consists of copper. Redruthite melts before the blowpipe in the outer flame with considerable effervescence to a bead, in the inner flame becomes solid and remains infusible: H=2'5 3 : lustre metallic : streak black. Covelline comports itself like redruthite H = i*5: lustre resinous. Bornite fuses before the blowpipe to a steel-grey magnetic globule : copper red or rariegated : exhibits the iron reaction : streak black. Copper pyrites decrepitates before the blowpipe and then fuses to a grey magnetic mass: lustre metallic : brass yellow : streak greenish black : exhibits the iron reaction. Carmenite is easily fusible before the blowpipe : lustre 42 Practical Guide to the Determination metallic : steel grey : streak lustrous. Rahtite froths up before the blowpipe and fuses ; yields on charcoal an incrustation of zinc : lead grey : streak reddish brown. Stromeyerite fuses before the blowpipe on charcoal to a grey globule with metallic lustre ; the silver present in the mineral is best detected by the wet way : lustre metallic : lead grey : streak the same. Stannine fuses before the blowpipe to a brittle grey bead : exhibits the iron reaction : flakes of tin are obtained by fusion with soda on charcoal : H=4'5 : lustre metallic: steel grey to brass yellow: streak black. Compounds of copper and sulphur only yield a characteristic copper bead after preliminary roasting : by this roasting a con- siderable proportion of the sulphur is eliminated in sulphurous dioxide. Argentite, when fused with soda, yields a globule of silver : intumesces and fuses before the blowpipe : H=2'5: streak lus- trous. Linneite colours the borax bead blue : fuses before the blow- pipe: H=5'5 : tin white. b. Hydrous minerals. Linarite PbO,SO 3 + CuO 5 HO. Bieberite (Kobalt Vitriol) CoO,SO 3 + 7HO. Blue Vitriol (Kupfervitriol) CuO 3 SO 3 + 5HO. Brochantite CuO,SO 3 + 3(CuO,HO). Langite 4CuO,SO 3 -j-4HO- Marcylite (CuO SO 3 CuS HO FeS) alteration product of a sulphide of copper. The following exhibit the copper reaction : Linarite gives on charcoal before the blowpipe a yellow incrustation : fuses easily : lustre adamantine : azure blue : streak light blue. Blue Vitriol intumesces and turns white before the blowpipe, then fuses and becomes black : lustre vitreous : sky blue : streak bluish white. Brochantite fuses before the blowpipe : lustre vitreous : trans- lucent : green : streak green. Langite only differs from broch- antite by containing a greater proportion of water. Marcylite Of Minerals by the Blowpipe. 4 3 treated with hydrochloric acid evolves sulphuretted hydrogen : exhibits the iron reaction : melts before the blowpipe : black. Bieberite colours the borax bead blue : lustre silky to vitreous : rose red : streak reddish white, 2. The fused mass exhibits the sulphur reaction with silver, but yields no metallic bead. a. Hydrous Minerals. Websterite Al a O 3 ,SO 3 + 9HO. Keramohalite A1 2 O 3 ,3SO 3 + 18HO. Johannite U 2 O 3 ,SO 2 + xHO. Goslarite (Zinkvitriol) ZnO,SO 3 + 7HO. Garnsdorfite (Pissophan) 2(Al 2 O 3 ,Fe 2 O 3 )SO3 + 15HO. Kakoxene Fe 2 O 3 A1 2 O 2 SO 3 -PO 5 HO. Ignition with cobalt solution produces a blue colouration in the following: Websterite is infusible before the blowpipe: H=:5. Keramohalite in turn e sees before the blowpipe and is then infusible: easily soluble in water: H = 2. Garnsdorfite shews a blue colour- ation, but not well marked : colours the borax bead with iron : turns black before the blowpipe. Goslarite assumes a green tint after ignition with cobalt solu- tion: when heated on charcoal before the blowpipe yields an incrustation which is yellow when hot and white when cold : intumesces before the blowpipe, leaving a white infusible mass. fohannite, when heated before the blowpipe, turns to a black friable mass : colours the borax bead green : grass-green : streak pale green. Kakozene decrepitates before the blowpipe : is converted in the oxidizing flame into a magnetic slaggy mass : imparts the iron colouration to the borax bead : yellow : streak yellow. b. Anhydrous minerals. Magnetic Iron Pyrites (Pyrrhotine), Fe 2 S 3 + 5FeS. Pyrite, FeS 2 . Marcasite (Strahlkies) FeS 2 . Alabandine (Mangan- glanz), MnS. Hauerite, MnS 2 . Blende, ZnS. Greenockite, 44 Practical Giiide to the Determination CdS. Molybdenite, MoS 2 . Christophite, 5ZnS + 3FeS. Copper Pyrites, Cu 2 S-fFe 2 S 3 . Bornite, 3Cu 2 S + Fe 2 S 3 . Redruthite, Cu 2 S. Covelline, CuS. Carmenite, Cu 2 S-f-CuS. Rahtite, Cu 2 S + ZnS. Stannine, (Zinnkies) 2FeS,SnS 2 + 2Cu 2 S, SnS 2 . The following impart an iron colouration to the borax bead : Pyrite fuses before the blowpipe in the inner flame to a black magnetic globule : H 6 6-5 : brass-yellow: streak grey. Mar- casite, when only warmed in the flame, evolves a sulphurous odour : blowpipe reactions similar to those of pyrite : H = 66-5 : brass- yellow, sometimes tinged with green : streak greenish black. Magnetic iron pyrites exhibits magnetic properties before ignition : melts before the blowpipe to a magnetic, more or less black mass : H = 3*5 4: bronze-yellow : streak greyish black. The following impart to the borax bead a violet colouration in the oxidizing flame : Alabandine fuses difficultly, and on the edges only, into a brown slag : H = 3'5 : black or brown : streak green. Hauerite when heated in the closed tube yields a subli- mate of sulphur and a green residue : H = 4 : brown-red : streak brown-red. The following, when heated on charcoal before the blowpipe, yield an incrustation which is yellow when hot and white when cold : Blende decrepitates before the blowpipe : infusible : H = 3*5 : streak yellowish white to brown. Christophite exhibits the iron reaction : H = 5 : velvet-black : streak blackish brown. Greenockite, when heated on charcoal before the blowpipe, yields a brown incrustation : yellow to orange and brown : streak orange- yellow to brick-red. Molybdenite colours the bead of microcosmic salt green in the reducing flame : turns brown when heated in the closed glass tube : infusible before the blowpipe. The following, after ignition (roasting), give a bead of copper when fused with soda and borax ; or impart a brown colour to Of Minerals by the Blowpipe. 45 the borax bead in the reducing flame (the latter reaction is much facilitated by the addition to the bead of a fragment of tin- foil): Redruthite melts with effervescence to a bead before the blowpipe : lustre metallic : H = 2*5 3 : streak black. Covelline comports itself before the blowpipe as redruthite : H = 1*5 : lustre resinous. Bornite melts before the blowpipe to a steel-grey magnetic bead : copper-red or variegated (iridescent) : streak black : exhibits the iron reaction. Copper pyrites decrepitates when heated before the blowpipe, and fuses to a grey magnetic mass: lustre metallic: brass-yellow, often assuming an iridescent and variegated tarnish : streak greenish black : exhibits the iron reaction. Carmenite: readily fusible before the blowpipe: lustre metallic : steel-grey : streak lustrous. Rahtite froths up and fuses before the blowpipe : yields an incrustation of zinc on charcoal : lead-grey : streak reddish brown. Stannine fuses before the blowpipe to a brittle bead : exhibits the iron reaction : by fusion with soda in the reducing flame, flakes of tin are obtained : H = 4-5: lustre metallic. 3. The fused mass yields a metallic bead, but does not exhibit the sulphur reaction. a. The bead is bismuth. Native Bismuth. Bismuth Ochre, BiO 3 . Wismuthspath, 4BiO 3 , 3CO 2 + 4HO. Eulytine, 2Bi0 3 ,3SiO 2 . Native bismuth fuses easily before the blowpipe : H = 2 '5 : lustre metallic : silver- white : generally superficially tarnished : streak the same : brittle. Bismuth ochre is reduced on charcoal before the blowpipe, and melts to a metallic bead : H = i "5 : lustre waxy : friable : yellow : streak yellowish white. Wismuthspath fuses, and is reduced on charcoal before the blowpipe : turns brown in the closed tube : effervesces with acids : evolves water in the closed tube : lustre vitreous : white. Eulytine, fusible before the blowpipe, leaves a skeleton of silica when fused in a bead of 46 Practical Guide to the Determination microcosmic salt : lustre adamantine : H = 4-5 : brown : streak yellowish grey. b. The bead is lead. Native Lead. Plattnerite (Schwerbleierz), PbO 2 . Minium, Pb 3 O 4 . Matlockite, PbCl + PbO. Mendipite PbCl 4- 2PbO Pyromorphite(Mimetite),* 3(3PbO,PO 5 ) + PbCl. Cerussite, PbO, CO 2 . Phosgenite, PbCl + PbO,CO 2 . Stolzite, PbO,WO 3 . Wul- fenite, PbO,MoO 3 . Vanadinite,3(3PbO,VO 3 )+PbCl. Dechenite,f PbO,VO 3 . Lehmannite (Krokoite), PbO,CrO 3 . Melanochroite, 3PbO 5 2CrO 3 . Eusynchite,f 3(Pb,Zn)O,VO 3 . Vauquelinite, 3CuO 2CrO 3 + 2(3PbO,2CrO 3 ). The following exhibit oxygen reactions : Plattnerite : iron- black : streak brown. Minium : red : streak orange-yellow. The following effervesce with acids: Cerussite decrepitates before the blowpipe : turns orange-yellow and is finally reduced to metallic lead : H = 3. Phosgenite: H = 2-5 : melts easily before the blowpipe in the outer flame to a bead which is pale yellow when cold : it is easily reduced with evolution of acid fumes : gives chlorine reactions. The borax bead turns green in the inner flame of the blowpipe, and yellow (vanadium) in the outer one. Vanadinite decrepitates strongly : melts into a globule which throws out sparks, and is reduced to lead : streak white. Dechenite fuses readily before the blowpipe : streak yellowish. Eusynchite yields an incrustation of zinc on charcoal : streak pale yellow. The following colour the borax bead green (chromium) in both flames: Lehmannite when heated before the blowpipe, decrepitates : fuses easily, and spreads over the charcoal : lustre adamantine : streak orange-yellow. Melanochroite decrepitates but slightly before the blowpipe, and fuses to a dark mass : streak brick-red. Vauquelinite exhibits the copper reaction : intumesces slightly * In mimetite arsenic entirely replaces the phosphorus, f Probably varieties of the same mineral. Of Minerals by the Blowpipe. 47 before the blowpipe and then melts with considerable efferves- cence into a dark grey bead : streak siskin-green. Pyromorphite decrepitates in the closed tube : melts on charcoal before the blowpipe in the outer flame to a bead which on cooling crystallizes on the surface, and yields a feeble white incrustation of lead chloride : colours the flame blue: many specimens evolve the odour of arsenic. (In Mimetite the phosphoric acid is replaced by arsenic acid.) Stolzite imparts a blue (wolfram) colouration to the bead of microcosmic salt in the reducing flame : fuses on charcoal to a cystalline bead with metallic lustre : streak grey. Wulfenite imparts a green (molybdenum) colouration to the bead of microcosmic salt in the reducing flame : decrepitates before the blowpipe, and fuses on charcoal : streak white. Mendipite, when heated on charcoal before the blowpipe, evolves an odour of hydrochloric acid, and is reduced to lead. Matlockite decrepitates, and then fuses to a greyish yellow globule. The presence of chlorine in mendipite and matlockite is best shown in the wet way. Native lead * is easily fusible : before the blowpipe furnishes'a well-marked yellow incrustation on charcoal : H = i '5 : lustre metallic, very liable to tarnish : streak lustrous. c. The metallic bead is silver. Native silver. Kerate (Hornsilber), AgCl. ' Bromite (Brom- silber), AgBr. lodite (lodsilber), Agl. Amalgam, AgHg x . Native silver fuses before the blowpipe : fracture hackly : streak lustrous. Kerate fuses in the flame of a candle ; and before the blowpipe into a brownish bead : fracture conchoidal : H = 1-5 : translucent : streak white : soluble in ammonia. * The occurrence ot this mineral in nature is very doubtful. 48 Practical Guide to the Determination Bromite in powder is clear green, passing quickly to grey on exposure to light : soluble in warm concentrated ammonia. lodite melts before the blowpipe to a globule of silver, and colours the flame purple-red : H = i : streak lustrous : soluble in concentrated hydrochloric and nitric acids with evolution of vapour of iodine. Amalgam decrepitates when heated in the closed tube, and yields drops of mercury : on charcoal, mercury is volatilized, leaving a spongy residue of silver : H = 3. d. The metallic bead is copper. Native Copper. Cuprite (Rothkupfererz) Cu 2 O. Melaconite, CuO. Atacamite,CuCl + 3(CuO,HO). Libethenite, 3CuO,PO 5 + CuO,HO. Phosphorochalcite, 3CuO,PO 5 + 3(CuO,HO). Throm- bolite, 3CuO,2PO 5 + 6HO. Malachite, CuO,CO 2 + CuO,HO. Chessylite (Azurite), 2(CuO,CO 2 ) + CuO,HO. Dioptase, CuO,SO 2 + HO. Chrysocolla,CuO,SiO 2 + 2HO. Crednerite,3CuO,2Mn 2 O 3 . Volborthite, 4(Cu,Ca)O,VO 3 + HO. The following are anhydrous : Native copper, fracture hackly : H=2*5 : copper-red : lustre metallic : streak lustrous. Cuprite turns black before the blowpipe, and fuses to a globule of copper : H=3'5 : carmine-red: streak brown-red. Melaconite is reduced before the blowpipe to a globule of copper : H = 3 : steel-grey to bluish or brownish black: streak the same. Crednerite is in- fusible before the blowpipe : exhibits the manganese reaction : H=4'5. The remaining minerals in d contain water. The following are infusible before the blowpipe : Dioptasewhzn heated before the blowpipe turns black in the outer and red in the inner flame : H = 5 : streak green : leaves a skeleton of silica in the microcosmic bead when fused in it. Chrysocolla before the blowpipe turns first black and then brown : H = 2*5 : streak greenish white : leaves a skeleton of silica when heated in the bead of microcosmic salt. Of Minerals by the Blowpipe. 49 The following effervesce with hydrochloric acid : Malachite fuses into a globule, and is reduced at a still higher temperature : green : streak green. Chessylite fuses before the blowpipe and is reduced : blue : streak the same. Atacamite colours the flame blue-green : H = 3. Libethenite fuses on charcoal before the blowpipe to a steel-grey globule : H = 3-5 : lustre resinous or vitreous : green : streak yellowish green. Phosphor ochalcite fuses before the blowpipe to a steel-grey globule : H = 4*5 : lustre vitreous : green : streak the same. Thrombolite comports itself as phosphorochalcite. Volborthite fuses before the blowpipe on charcoal to a black slag : heated in the closed tube evolves water and turns black : H = 3-5 : olive green : streak yellow. e. The metallic bead consists of some other metal. Earthy Cobalt ', CoO, 2MnO 2 + 4HO (cupriferous) Nickelsmaragd 3 NiO,CO 2 + 6HO. Native Gold. Earthy cobalt colours the borax bead blue : fused with soda and nitre on platinum-foil, yields a green mass. Nickelsmaragd imparts to the borax bead a brown-red coloura- tion in the outer flame : effervesces with acids. Native gold is very difficultly fusible : yellow: H=2'5 : lustre metallic : high specific gravity. III. The borax bead is amethystine in the outer flame. 1. Minerals with metallic lustre, Pyrolusite (Braunstein), MnO 2 . Hausmannite, Mn 3 O 4 . Braunite, Mn 2 O 3 . Manganite, Mn 2 O 3 HO. Psilomelane, MnO 2 BaO HO.* Heated with sulphuric acid and sodium chloride all these minerals evolve more or less chlorine. Pyrolnsite yields much * Some varieties are nearly anhydrous, and consist of little other than man- ganese oxide. Psilomilane is probably a mixture of different minerals. D 5O Practical Guide to the Determination chlorine : H = 2 : streak black. Hausmannite yields but little chlorine: H = 5-5 : streak reddish brown. Braunite yields little chlorine : H = 6-5 : streak black. Manganitey\d&s little chlorine : heated in the closed tube, it evolves water : H = 4 : streak brown. Psilomelane yields little chlorine: in the closed tube evolves water : 11=5-5 : lustre imperfectly metallic : streak brown-black : lustrous : easily soluble in hydrochloric acid : from the solution so obtained sulphuric acid throws down a precipitate (of barium sulphate). 2. Minerals without metallic lustre. Diallogite, MnO,CO 2 . Manganocalcite, (MnO,CaO,MgO)CO 2 . Rhodonite (Kieselmangan), MnO,SiO 2 . Tephroite, 2MnO,SiO 2 . Kelvin (MnO FeO SiO 2 BiO 3 MnS). Wad, MnO 2 MnO, CaO BaO HO. Karpholite, 2(Al,Mn) 2 O 3 ,3SiO 2 + 3HO . Garnet (manganesian), 3(Mn,Ca)O,2SiO 2 + Al 2 O 3 SiO 2 . Pyro- chroite, MnO,HO. Manganese Epidote, 3(2MnO,SiO 2 ) -f 2A1 2 O 3 , 3SiO 2 . Zwiselite, 3(Fe,Mn)O,PO 5 +FeF. Childrenite, A1 2 O 3 Fe 2 O 3 PO 5 HO. Tantalite, (Fe,Mn)O,TaO 2 . Columbite (Nio- bite), (Fe,Mn)O,NbO 3 . Calamine (Zinkspath), in part (ZnMn)O, CO 2 . Triplite, 4(Fe,Mn)O,PO 5 . Triphyline, 3(Li,FeMn)O,PO 5> The following, when heated in the closed tube, evolve water : Wad evolves chlorine when heated with sulphuric acid and sodium chloride : shrinks when heated before the blowpipe : H = i : lustre resinous : streak brown : brown or grey, discoloured. Pyrochroite, steel-grey to iron-black: lustre nacreous : H = 1 1*5 : when heated, turns verdigris-green and then brown. Karpholite, when heated before the blowpipe, swells up, turns white, and melts with difficulty to a brown slag : H = 5 : lustre nacreous : straw-yellow : streak white. Childrenite swells up before the blowpipe into ramifications : colours the flame bluish green : evolves a con- siderable amount of water: H = 5 : transparent : lustre vitreous : pale yellowish brown : streak yellowish. The following effervesce when heated with hydrochloric acid : Diallogite decrepitates before the blowpipe : H=4 : streak reddish Of Minerals by the Blowpipe. 51 white. Manganocaldte : H = 5 : streak white. Calamine yields a zinc incrustation when heated on charcoal. A skeleton of silica is left in the bead of microcosmic salt by the following (a and b). (a) Soluble in hydrochloric acid: Tephroite fuses before the blowpipe to a black slag : H = 5^5 : lustre vitreous : brownish or grey : streak somewhat lighter. Helvin intumesces when heated before the blowpipe, and fuses to an opaque bead : deposits a bismuth incrustation on charcoal : exhibits a feeble sulphur re- action H = 6 : lustre resinous : yellowish green : streak grey. (1)) Insoluble in hydrochloric acid : Rhodonite fuses before the blowpipe on charcoal to a black globule: H = 5*5 : reddish brown streak : reddish white. Epidote melts readily to a black glass : H = 6*5 : reddish black : streak light grey. Garnet melts easily : H = 7 : reddish brown : streak grey. Zwisdite decrepitates before the blowpipe and fuses easily: H = 5 : brown : lustre resinous : streak greyish white : moistened with hydrochloric acid, imparts a pale bluish green colouration to the flame. Tantalite : infusible before the blowpipe : exhibits a feeble man- ganese reaction : H = 6*5 : iron-black : streak brown. Columbite infusible before the blowpipe : exhibits a feeble manganese reaction : H r= 6 : brownish black. Triplite fuses very readily with effervescence before the blow- pipe on charcoal into a lustrous metallic globule, which is attracted by the magnet : easily soluble in hydrochloric acid : H = 5'5: lustre resinous: streak greenish grey to yellowish brown. Trip hy line fuses very easily and quietly on charcoal before the blowpipe to a steel-grey magnetic globule : imparts to the flame a feeble colouration which is bluish green, and sometimes red : exhibits a feeble manganese reaction : lustre resinous : greenish grey : streak pale grey. 52 Practical Guide to the Determination IV. The mineral powder assumes a green colour when ignited with cobalt solution. Spartalite, ZnO. Calamine, ZnO,CO 2 . Zinkbliithe, 3ZnO,CO 2 + 3HO. Gahnite, (Zn,Fe,Mg)O,Al 2 O 3 . Willemite, 2ZnO,SiO 2 . Smithsonite, 2ZnO,SiO 2 + HO. The following effervesce with hydrochloric acid: Calamine infusible : H = 5 : deposits on charcoal a sublimate which is yellow while hot, and white when cold. Zinkbliithe yields water when heated in a closed tube : H = 2-5. The following leave a skeleton of silica in the microcosmic salt bead : Smithsonite gives off water in the closed tube and decrepitates: H = 5. Wf&mifeyiMs no water: H = 5-5. Spartalite : soluble in hydrochloric acid : H = 4 : lustre adaman- tine : streak yellow. Gahnite: insoluble in hydrochloric acid : H = 7*5 : lustre vitreous : streak white : greenish to black. V. Minerals entirely soluble in hydrochloric acid. 1. Fusible before the Blowpipe. a. Water evolved on heating in the closed tube (hydrous minerals']. Sassoline, BO 3 ,3HO. Hydroboracite, 3(Ca,Mg)O,4BO 3 + 9HO. Uranite, (Ca,Cu)O,2PO 5 + 2U 2 O 3 + 8HO. Dufrenite, 2(2Fe 1 O 8 ,PO 8 ) +6HO. Vivianite, 3FeO,PO 5 + 8HO. Sassoline colours the flame green : sublimes in the closed tube : H = i : soluble in water. Hydroboracite melts before the blowpipe, and colours the flame feebly green : H=2 : imperfectly soluble in water. Uranite exhibits the uranium reaction. Calciferous variety gives a sulphur-yellow streak. Cupriferous variety gives an apple-green streak. Dufrenite imparts to the borax bead an iron colouration : fuses Of Minerals by the Blowpipv. 53 before the blowpipe to a slaggy globule : H = 3-5 : lustre silky : green to brown : streak yellowish grey. Vivianite intumesces before the blowpipe, turns red and melts into a magnetic globule : H 1-5 : lustre vitreous : streak bluish white. b. No water evolved on heating in the dosed tube (anhydrous minerals). Wagnerite, 3MgO,PO 5 + MgF. Apatite, (Spargelstein), 3(3CaO, PO 5 ) + Caj p 1 . Cryolite, 3NaF+Al 2 F 3 . Amblygonite,5(Li,Na)O, 3PO 5 + 5A1 2 O 3 3PO 5 + (LiF + A1 2 F 3 ). Chiolite, 3NaF + 2Al 2 F 3 . Stassfurthite,* 2(3MgO,4BO 3 + HO) + MgCl. Yttrotitanite, 3CaO, SiO 2 + 2R 2 O 3 ,3SiO 2 + YO,TiO 2 . Molybdanocker, MoO 3 .t Stassfurthite colours the flame feebly green : at a high tempera- ture gives off water : H = 7. A slight bluish green colouration is imparted to the flame by the following minerals when moistened with sulphuric acid : Wagnerite fuses with effervescence, before the blowpipe : H = 3 : dissolves in dilute sulphuric acid. Apatite fuses quietly : H = 5 : insoluble in dilute sulphuric acid. Amblygontit fuses very easily : H=2 : exhibits feebly the reactions of fluorine and lithium. Cryolite fuses in an ordinary flame to a limpid bead, which becomes opaque on cooling : exhibits, when fused in a glass tube, the reaction of hydrofluoric acid: H = 2-5. Chiolite comports itself similarly to cryolite : H = 4 : both impart a sodium coloura- tion to the flame. Yttrotitanite leaves a skeleton of silica in the bead of microcosmic salt : colours the microcosmic head with titanium in the inner flame. Molybdanocher exhibits the molybdenum reaction : earthy : streak yellow. * Vai-iety due to deliquescence of boracite. t Decomposition product. 54 Practical Gztide to tJie Determination 2. Infusible before the Blowpipe, a. Hydrous minerals. Uranochre, UjOa + *HO. Calaite (Turquoise), 2A1*O 3 ,PO 5 + 5HO. Peganite, 2A1 2 O 3 ,PO 5 -f 6HO. Fischerite, 2A1 2 O 3 ,PO 5 + 8HO. Lanthanite, 3LaO,CO 2 + 4HO. Parisite, CeO LaO CO 2 HO. Wavellite, 3 (4A1 2 O 3 ,3PO 5 + 18HO) -f A1 2 F 3 . Gibb- site, A1 2 O 3 ,PO 5 + 8HO. Hydrargillite, A1 2 O 3 ,3HO. The following, when moistened with sulphuric acid, impart a green colouration to the flame : Calaite turns brown when heated before the blowpipe : H = 6 : lustre waxy : green : streak white. Peganite comports itself as calaite : H = 3*5. Fischerite comports itself as calaite : H = 5. Wavellite^ when heated in the closed tube, evolves a certain quantity of hydrofluoric acid : exfoliates and turns white when heated before the blowpipe : turns blue with cobalt solution. Gibbsite is like wavellite, but remains un- changed before the blowpipe. The following effervesce with hydrochloric acid : Lanthanite turns brown when heated in the tube : lustre nacreous or dull : streak white: 11 = 2*53. Parisite turns brown in the closed tube : lustre vitreous : streak yellowish white : H = 4/5. Uranochre exhibits the uranium reaction with the bead of microcosmic salt : turns red in the closed tube : H = i : earthy : yellow. Hydrargillite turns white before the blowpipe, exfoliates, and incandesces strongly, without melting : with cobalt solution be- comes blue : H = 2*5 : translucent. b. Anhydrous minerals. Pechuran UO,U 2 O 3 . Chromochre, Cr 2 O 3 . Magnesite, MgO, CO 3 . Monazite 3(Ce,La)O,PO 5 . Polykrase, TiO 2 , NbO 5 , ZrOa YO FeO. Fluocerite, CeF. Periclase, MgO. Apatite, 3(3CaO,PO 6 ) + Ca | p 1 Yttrocerite, CaF YF CeF. Of Minerals by the Blowpipe. 55 Pechuran exhibits the uranium reaction: H = 5'5: lustre resinous : streak black. Chromochre imparts a fine green colouration to the borax bead : soft and earthy. Apatite, moistened with sulphuric acid, imparts a feeble bluish- green colouration to the flame : H = 5. Magnesite effervesces with hydrochloric acid : exhibits a flesh- colour when ignited with cobalt solution : H = 4. Monazite^ when moistened with sulphuric acid,colours the flame bluish green : reddish brown : streak reddish yellow : [=5*5. Polykrase decrepitates before the blowpipe : ignited quickly, glows and is converted to a yellowish brown mass: black, yellowish by transmitted light: lustre imperfectly metallic: streak yellowish brown : H = 6. Fluocerite^ heated with sulphuric acid, evolves hydrofluoric acid : turns white before the blowpipe : pale red, yellowish: streak yellowish white : H = 4 5. Yttroceritc similar to fluocerite. Periclase shows a flesh-red colouration when ignited with cobalt solution : transparent : dark green : lustre vitreous : H = 6. VI. Soluble in (decomposed by) hydrochloric acid, leaving a jelly of silica. 1. Fusible before the Blowpipe. a. Hydrous minerals. Datholite, CaO, 2 SiO 2 -f-CaO,BO 3 + HO. Natrolite, NaO,SiO. 2 + Al 2 O 3 ,2SiO 2 + 2HO. Analcime, NaO,SiO 2 + Al 2 O 3 3SiO 2 + 2HO. Scolezite, CaO,SiO 2 + Al 2 O 3 ,2SiO 2 + 3HO. Laumonite, CaO,SiO 2 + Al. 2 O 3 ,3SiO 2 + 4HO. Phillipsite, R*O,SiO 2 + Al 2 O 3 ,SiO 2 + 5HO. Gismondine, CaO,SiO 2 -f Al 2 O 3 ,SiO 2 +4HO. Gmelinite, NaO,SiO 2 + Al 2 O 3 ,3SiO 2 + 6HO. Faujasite, R*O,2SiO 2 + A1 2 O 3 , Thomsonite, 3 (CaOSiO 2 ) + 3(Al 2 O 3 ,SiO 2 )+7HO. * R = Ca,K,Na. 56 Practical Guide to the Determination Hisingerite, 3(FeO,SiO 2 ) + 2(Fe 2 O 3 ,SiO 2 ) -f 6HO. Nontronite, Fe 2 O 3 3SiO 2 -f5HO. The following impart the yellow colouration of sodium to the flame : Natrolite, when heated before the blowpipe, becomes clouded, and melts quietly to a clear glass : H= 5 : lustre vitreous : the powdered mineral, moistened with water, often shows an alkaline reaction. Anakime melts into a clear glass containing bubbles : H = 5*5 : lustre vitreous or nacreous : sometimes exhibits an alkaline reaction. Phillipsite swells up when heated before the blowpipe, and then melts quietly to a clear glass: H = 4*5 : lustre vitreous. Faujasite exhibits a feeble sodium coloura- tion, swells up before the blowpipe, and melts to a white enamel : lustre adamantine or vitreous : H = 7. Gmelinite shows but a feeble sodium colouration : melts easily to a blebby, slightly translu- cent enamel: H = 4-5. Thomsonite shows a feeble sodium coloura- tion :' intumesces considerably before the blowpipe, becomes white and opaque, and then melts quietly to a white enamel : H = 5 5-5. Datholite colours the flame feebly green with boracic acid : intu- reesces and fuses before the blowpipe : H = 5*5 : lustre vitreous or msinous : brittle : H = 5*5. Scolezite, when heated before the blowpipe, curls up, and melts easily to a blebby grass : H = 5*5 : lustre vitreous. Laumonite intumesces before the blowpipe, and melts into a milk-white glass : H = 3*5 : very fragile : reduced to powder and moistened, often exhibits an alkaline reaction. Gismondine intumesces before the blowpipe, decrepitates, be- comes opaque and white, then melts into a white blebby enamel : H = 5 : lustre vitreous. Hisingerite colours the borax bead with iron : melts before the blowpipe to a dull black globule, which is attracted by the magnet : lustre resinous : black : streak brownish yellow. H = 3. Nontronite becomes reddish before the blowpipe : after ignition is magnetic : straw-yellow : greasy to the touch : very soft. Of Minerals by the Blowpipe. 5 7 b. Anhydrous minerals. Hauyne, 3 (NaO,SiO 2 -f Al 2 O 3 ,SiO 2 ) + 2CaO,SO 3 . Nosean, 3(NaO,SiO 2 + Al 2 O 3 ,SiO 2 ) -r- NaO,S0 3 . Sodalite, 3(NaO,SiO 2 ) + Al 2 O 3 ,SiO 2 ) + NaCl. Lapis-lazuli, SiO 2 ,-Al 2 O 3 ,-SO 3 -NaO, CaO. Skolopsite, 3(3NaO,SiO 2 + Al 2 O 3 ,SiO 2 )+NaO,SO 3 . Wollas- tonite, CaO,SiO 2 . Eudyalite, 2R*O,SiO 2 + ZrO 2 ,2SiO 2 . Euko- lite,Nb0 5 , -ZrO 2 ,-SiO 2 ,-CuO,-NaO. Nepheline,4RfO,SiO 2 + 4Al 2 O 3 ,5SiO 2 . Scapolite, 3(3CaO,SiO 2 ) + 2(Al 2 O 3 ,3SiO 2 ). Somer- villite, 2(3RtO,2SiO 2 ) + R 2 O 3 ,SiO 2 . Tschewkinite (SiO 2 , TiO 2 ,-CeO,-LaO,-FeO,-CuO). Orthite, 3(3R||O,2SiO 2 ) + 2(Al 2 O 3 ,SiO 2 ) . Fayalite, 2FeO,SiO 2 . Lievrite, CaO,-FeO 2 Fe 2 O 3 . SiO 2 . The following give the sulphur reaction when fused with soda on charcoal : Hauyne decrepitates before the blowpipe, and melts to a bluish green glass : H = 5-5 : lustre vitreous : white to blue : streak bluish white : the moistened mineral powder generally has an alkaline reaction. Lapis-lazuli melts with difficulty to a white glass : H = 5'5 : lustre feebly vitreous : streak pale blue : treatment with hydrochloric acid evolves sulphuretted hydrogen. Skolopsite froths up when heated before the blowpipe, and melts to a greenish glass : H = 5 : smoke-grey to reddish white. Nosean melts on the edges only, to a blebby glass : H = 5 *5 6. (Probably a variety of hauyne.) The following colour the flame blue when heated with a borax bead saturated with copper oxide : Sodalite melts before the blow- pipe to a clear colourless glass : H = 6. Eudyalite melts before the blowpipe to an opaque green glass : H = 5 5-5. The following are magnetic after fusion : Fayalite fuses before the blowpipe to a greyish black, brittle, magnetic globule, with metallic lustre : the borax bead exhibits the iron colouration : in some cases, on addition of tin, a copper bead is obtained in the R - Na,Ca,Fe,Mn t R = Na,K,Ca. t RO = CaO,MgO,NaO,KO. R 2 O 3 = Al 2 O 3 ,Fe 2 O;,. || R = Ca,Ce,Fe. 5$ Practical Guide to the Determination inner flame : H = 6*5 : streak greenish grey : magnetic even before ignition. Lievrite fuses easily to an iron-black magnetic globule the borax beads are coloured with iron : streak black : H = 5-5 6. Wollastonite melts quietly to a translucent glass : H = 5. Eukolite fuses more easily. The hydrochloric acid solution, after separation of the silica, turns blue when boiled with tin foil : the blue colour disappears on dilution: red-brown. Scapolite froths up before the blowpipe, and melts to a blebby glass: H = 5 5-5. Nepheline fuses without effervescence: H = 5*5 : lustre vitreous or resinous: the moistened mineral powder shows an alkaline reaction. Somervillite melts slowly to a yellowish or blackish glass : H = 5-5- Tschewkinite, when heated before the blowpipe, intumesces, sparkles, and becomes porous : heated more strongly, turns yellow, and at a white heat melts into a black glass : streak dark brown: H = 5-5. Orthite intumesces before the blowpipe and fuses to a black glass : evolves some water in the closed tube : brown to black : streak yellowish to greenish grey : H = 6. 2. Infusible before the Blowpipe, a. Hydrous minerals. Thorite, 2ThO,SiO 3 + 2HO. Cerite, 2CeO,SiO 2 + 2HO. Meerschaum 2MgO,3SiO 2 + 2HO. Schillerspar (Mg,Fe)O,SiO 2 + HO. Serpentine, 3MgO,2SiO 2 + 2HO. Antigorite, 4R*O 3SiO 2 + HO.- Monradite, 4(MgO,SiO 2 ) + HO. Neolite, 3(MgO,SiO 2 )+HO. Chrysotite,3MgO,2SiO 2 +2HO. Allophane, Al 2 O 35 SiO 2 + 5HO. Collyrite, 2Al 2 O 3 SiO 2 + 10HO. Orangite, 2ThO,SiO 2 + 3 HO. The following turn faintly flesh-red when ignited with cobalt * R = Mg,Fe. Of Minerals by thv Blowpipe. 59 solution : Serpentine is fusible on thin edges : heated in the closed tube it turns black and yields water: H = 3 4: lustre resinous or dull : the mineral powder exhibits an alkaline reaction. Schillerspar is like serpentine : lustre nacreous, on large cleavage planes only: this and serpentine are, after ignition, acted on by the magnet: before the blowpipe turns brown: H = 3*5 4. Antigorite: thin splinters melt before the blowpipe into a yellowish brown enamel : =2*5. Monradite : honey-yellow: before the blowpipe becomes darker : H = 6 : lustre vitreous. Neolite : H = i : lustre resinous to silky : greasy to the feel. Chrysotite turns white before the blowpipe : lustre nacreous to metallic. Meerschaum shrinks before the blowpipe : absorbs water : very light: H=2. The following turn blue when ignited with cobalt solution : Allophane colours the flame green, yields much water : H = 3. Collyrite absorbs water, becomes translucent, and flies to pieces : H = i-S- . Thorite, when heated before the blowpipe, loses its black colour, and turns yellow without fusing : lustre vitreous : black : streak greyish red : H = 4*5, Cerite: clove brown : streak greyish white: H = 5-5. Orangite, when heated before the blowpipe, turns dark brown, regaining its colour on cooling: decrepitates feebly and glows: orange-yellow : streak pale yellow : H = 4*5. b. Anhydrous minerals. Gadolinite, 2MgO,SiO 2 + 2YO,SiO 2 . Gehlenite, 3R*O,SiO 2 + Rf 2 O 2 ,SiO 2 . Olivine, 2MgO,SiO 2 . Boltonite, 3MgO,SiO 2 . Chondrodite, 2(MgO,3SiO 2 ) + MgF. Gadolinite. The glassy varieties when heated to redness on thin edges, suddenly glow brightly and swell. Varieties exhibiting a splintery fracture do not exhibit these characteristics, but turn * R = Ca,Mg,Fe. t R 2 O 3=: Al a O 8 , F^O-,. 60 Practical Giiide to the Determination white and swell into cauliflower-like ramifications : H=6'5 : black : streak, greyish green : infusible or difficultly fusible. Gehlenite does not swell before the blowpipe : H 5-5 : lustre feeble, resinous : grey : streak white. Olivine is unchanged before the blowpipe : H = 7 : lustre vitreous : greenish yellow : streak white : the moistened mineral powder shows an alkaline reaction. Chondrodite becomes milk-white before the blowpipe : it exhibits, when strongly heated in the glass tube, a feeble reaction of hydro- fluoric acid : H = 6 : yellowish brown or reddish : streak white. Boltonite comports itself as the preceding before the blow- pipe : H = 5 '5 : lead-grey to yellow. VII. Soluble in hydrochloric acid with separation of silica, without the formation of a jelly. 1. Hydrous Minerals. Apophyllite,4(2CaO,3SiO 2 -f KO,3SiO 2 ) + 16HO. Pectolite, 2NaO,3SiO 2 -f 8(CaO,SiO 2 ) 4- 3HO. Okenite, CaO,2SiO 2 + 2HO. Pyrosklerite,* 3(2MgO,SiO 2 ) + Al 2 O 3 ,SiO 2 + 4HO. Analcime, NaO,SiO 2 + Al 2 O 3 ,3SiO 2 + 2HO. Chonikrite, SiO 2 - Al 2 O 3 -MgO-CaO-FeO HO. Brewsterite, RfO,2SiO 2 + Al 2 O 3 ,3SiO 2 + 5HO. Stilbite, CaO,3SiO 2 + Al 2 O 3 ,3SiO 2 + 6HO. Chabasie, CaO,SiO 2 + Al 2 O 3 ,3SiO 2 + 6HO. Prehnite, 2(CaO,SiO 2 ) + Al 2 O 3 ,SiO 2 + HO. Harmotome, BaO,2SiO 2 + Al 2 O 3 ,3SiO 2 + 5HO. Heulandite, CaO,3SiO 2 + Al a O 3 ,3SiO 2 + 5HO. Palagonite^ 3(RO,SiO 2 ) -f- 2R 2 O 3 ,3SiO 2 + 9HO. Chlorite, (Ripidolite) SiO 2 -Al 2 O 3 -FeO-MgO-HO. Meerschaum, 2MgO,3SiO 2 + 2HO. Gymnite, 4MgO,3SiO 2 + 6HO. Serpen- tine, 3MgO,2SiO 2 + 2HO. Neolite, 3(MgO,SiO 2 ) + HO. Mosandrite, SiO 2 . - TiO 2 - CeO - LaO - HO. The following assume a faint flesh-red colour when ignited with cobalt solution. Meerschaum shrinks before the blowpipe : absorbs * Contains Cr. f R^Sr,Ba,Ca. J R=Fe,Ca,Mg. Of Minerals by the Blowpipe. 61 water : adheres to the tongue : H = 2. Gymnite turns dark brown before the blowpipe : H = 2-5 : yellow : translucent. Serpentine : fusible in thin splinters : becomes black when heated in the closed tube: H = 34: lustre, resinous or dull. Neolite: H = i : lustre resinous or silky : greasy to the touch. Chlorite exfoliates before the blowpipe, and fuses in very thin splinters : imparts the iron colouration to the borax bead : H = 1-5 : greenish : streak greenish grey. The hydrochloric acid solution yields no precipitate on addition of ammonia: Apophyllite quickly becomes dull when heated before the blowpipe, intumesces and fuses easily into a blebby glass : brittle : lustre vitreous, and on some faces nacreous : the moist- ened mineral powder generally shows an alkaline reaction : H = 4'5 5. Pectolite yields but little water: fuses to an enamel-like glass : the mineral powder, after ignition, is decom- posed by hydrochloric acid with formation of a jelly : H = 4 5. Okenite fuses, with effervescence, into a porcelainous mass : lustre feeble, nacreous : after ignition is slightly attacked by hydrochloric acid: H = 5*5 5. The hydrochloric acid solution yields a precipitate with ammonia: Pyrosklerite imparts the green colouration of chro- mium to the borax bead ; melts difficultly to a grey glass ; H = 3. Analdme fuses into a clear blebby glass : H = 5*5. Chonikrite melts easily, with ebullition, into a greyish glass: H = 3. Brewsteritevfaen. heated before the blowpipe becomes opaque, intumesces, and melts with difficulty . the solution in hydro- chloric acid gives a precipitate of barium sulphate with sulphuric acid. Stilbite intumesces before the blowpipe, and melts into a white enamel : H = 3 '5 : lustre vitreous, nacreous on cleavage faces : the mineral powder often has an alkaline reaction. Chabasie melts easily into a blebby, almost opaque enamel : H=4 : lustre vitreous. Prehnite yields but little water in the closed tube : intumesces 62 Practical Guide to the Determination strongly and melts into a white or yellowish glass : after strong ignition dissolves in hydrochloric acid with formation of a jelly : H = 6: lustre vitreous, nacreous on terminal planes: grey -green. Harmotome fuses quietly into a white, clear glass : solution yields a precipitate of barium sulphate with sulphuric acid : H=4*5 : lustre vitreous. Heulandite exfoliates before the blowpipe, intu- mesces, and melts into an enamel : H=3'5 4: lustre vitreous, nacreous on cleavage faces. Palagonite fuses easily to a lustrous magnetic bead : exhibits the iron colouration in the borax bead : H = 4*5 : lustre resinous : brown: streak yellow. Mosandrite yields much water : turns brownish yellow in the closed tube : fuses easily into a brownish green bead : imparts to the bead of microcosmic salt the titanium colouration: streak greyish brown : H n: 4. 2. Anhydrous Minerals. Leucite, KO,SiO 2 + Al 2 O 3 ,3SiO 2 . Tachylite, 3R*OSiO 2 + A1 2 O 3 2SiO 2 . Schorlomite, 2(2CaO,TiO 2 ) + FeO,3SiO 2 . Scapolite, 3CaO,2SiO 2 + 2(A1 2 O 3 ,SiO 2 ). Wohlerite, NbO 5 ZrO 2 SiO 2 CaO NaO. Labradorite, CaO,SiO 2 + Al 2 O 3 ,2SiO 2 . Anorthite, CaO,SiO 2 + Al 2 O 3 ,SiO 2 . Grossular (greenish variety of garnet), 3CaO,2SiO 2 + Al 2 O 3 ,SiO 2 . Sphene, 2CaO,SiO 2 + CaO,2TiO 2 . Knebelite, 2FeO,SiO 2 + 2MnO,SiO 2 . Yttrotitanite, 3(CaO,SiO 2 ) + Rf 2 O 3 ,SiO 2 + YO,3TiO 2 . The following exhibit titanium colourations in the bead of microcosmic salt: Yttrotitanite fuses with ebullition into a black, lustrous slag : H = 6-5 : brownish black : lustre resinous : streak greyish brown. Sphene melts in thin splinters to a blackish glass : H = 5 *5 : yellow, green, brown : lustre vitreous : streak white. Schorlomite fuses with great difficulty in thin splinters : H = 7 : black : streak greyish black : colours the borax bead with iron. Leucite i only difficultly soluble in hydrochloric acid : infusible : ash-grey to yellowish : streak white : H = 5*5. * R = Fe,Ca,Mg,Na.K. t R 2 O 3 =Fe 2 3 ,Al a O 8 ,Mn 2 O s Of Minerals by the Blowpipe. 63 Tachylite melts easily and quietly to a lustrous glass : imparts a feeble colouration of titanium to the bead of microcosmic salt. Scapolite before the blowpipe glows, intumesces, and melts into a white,' blebby glass : H = 5 : streak light grey : white, or light coloured. Wohkrite fuses into a yellowish enamel : the hydrochloric acid solution turns blue when boiled with tin-foil : honey-yellow : H = S-S. Labradorite melts into a clear glass : H = 6. Anorthite comports itself as labradorite : H = 6. Grossular (variety of garnet) fuses quietly : H=7 : streak grey. Knebelite infusible : imparts in the outer flame, the amethystine colouration of manganese to the borax bead. VIII. Insoluble in hydrochloric acid : skeleton of silica left in the bead of microcosmic salt 1. Fusible before the Blowpipe. Danburite, CaO SiO 2 BO 3 . Lepidolite, 2LiO,SiO 2 + 3Al 2 O 3 , 2SiO 2 + LiF. Petalite, A1 2 O 3 LiO NaO SiO 2 . Spodu- mene, 3LiO,SiO 2 + 4Al 2 O 8 ,3SiO 2 . Diallage, (Ca,Mg,Fe)O,SiO 2 . Diopside (variety of Augite), (Ca,Mg)O,SiO 2 . Augite (Pyroxene), (Ca,Mg,Fe)0, I^A Axinite, A1 2 3 - Fe 2 O 3 - MnO - CaO MgO SiO 2 BO 3 . Grammatite (variety of Hornblende), CaO,SiO 2 . Amphibole (Hornblende), MgO CaO, FeO SiO 2 . Sphene, CaO,2TiO 2 + CaO,2SiO 2 . Orthoklase, KO,3SiO 2 + Al 2 O 3 ,3SiO 2 . Albite, NaO,3SiO 2 + Al 2 O 3 ,3SiO 2 . Oligoklase, 2NaO,3SiO 2 + 2Al 2 O 3 ,3SiO 2 . Zoisite, 3CaO,2SiO 2 + 2R* 2 O 3 ,SiO 2 . Epidote, 3(Ca,MnFe)O,2SiO 2 + 2Rt 2 O 3 ,SiO 2 . Garnet (Pyrope), 3RJO,2SiO 2 ^ R 2 O 3 SiO 2 . Vesuvian (Idocrase), 3CaO,2SiO 2 + Al 2 O 3 ,SiO 2 . Potash Mica, KO,3SiO 2 + Al 2 O 3 ,SiO 2 . Acmite, * R - Fe, Al t R = Fe, Al, Mn. J R = Fe, Ca,Mg,Mn. R=Al,Fe,Cr. 64 Practical Guide to the Determination 2NaO, 3SiO 2 + 2Fe 2 O 3 >3SiO 2 . Tourmaline, BO 3 ,-SiO 2 ,-KO,- NaO, CaO, MgO, FeO, A1 2 O 3 , Fe 2 O 3 - The following impart to the flame the red colouration of lithium : this reaction is intensified by fusion with potassic hydric sulphate (acid sulphate of potash). Lepidolite fuses easily, with ebullition, into a blebby glass : exhibits the reaction of fluorine : H = 2-5. Petalite melts quietly into a white enamel: H = 6. Spodumene intumesces before the blowpipe and then fuses into a clear glass : H=6 5 : lustre vitreous, nacreous on cleavage faces. The following impart to the flame the green colouration of boracic acid. Danburite fuses into a bead which is clear when hot and opaque when cold : often yields water : lustre vitreous : H = 7 : yellow : streak white. Axinite melts easily, with in- tumescense to a dark green glass. H = 7 : lustre vitreous : clove-brown to violet-blue. Tourmaline melts difficultly and intumesces : H = 7*5. Diallage fuses before the blowpipe : generally green and opaque : cleavage well marked, parallel to ooP oo (orthopinakoid). Diopside fuses into a white glass : H = 6 : colourless or bottle- green. Augite fuses into a black glass : H = 6 : dark green to black : the moistened mineral powder often exhibits an alkaline reaction. Grammatite melts with intumescence into a white glass : white : H = 5 6. Hornblende (Amphibole) the same, forming a grey glass. The moistened powder generally exhibits an alkaline re- action: H 5 6 : generally some shade of green. Sphene exhibits the titanium reaction : melts with intumescence to a blackish glass : H = 5 55. Orthoklase (Sanidine, Adularia} fuses quietly: cleavage well marked, in two directions inclined to one another at a right angle : H = 6. Oligoclase, Albite, &c. : cleavage well marked along planes not inclined to one another at right angles : H = 6. Zoisite melts with intumescence into a blebby slag, or into a Of Minerals by the Blowpipe. 65 mass ramifying like a cauliflower: grey: after fusion is gela- tinized by hydrochloric acid. Epidote: the same, the glass being blacker brown : green : H=6'5 Thulite: the same : manganese colouration in the borax bead. Garnet fuses quietly : attacked to some extent by concentrated acids : H = 7. Vesuvian (Idocrase) the same, fusing with rather more difficulty, and intumescing : the moistened powder shows an alkaline reaction. Potash mica, when heated before the blowpipe, loses its trans- parency, becomes white and brittle, and then fuses into an enamel- like glass. In the closed tube yields some water, exhibiting the acid reaction of hydrofluoric acid : H = 2 '5. Acmite melts easily into a black glass : shows the iron reaction with borax : is powerfully attacked by acids: brownish black, reddish brown : streak yellowish grey': H = 6 6*5. 2. Infusible before the Blowpipe. Quartz (Rock Crystal), SiO 2 . Magnesia Mica, 3MgO,2SiO 2 + Al 2 O 3 .SiO 2 . Talc, MgO,2SiO 2 + HO, Bronzite and Hypersthene, (Mg,Fe)O,SiO 2 . Cordierite2(Mg,OSiO 2 ) + 2.\l 2 O 3 ,3SiO 2 . Stauro- lite, 4R* 2 O 3 ,3SiO 2 . Beryl (Emerald), A1 2 O 3 ,3SiO 2 + 3GO,SiO 2 . Euklase, A1 2 O 3 ,HO + GO,SiO 2 . Phenakite, 2GO,SiO 2 . Zircon, ZrO 2 SiO 2 . Topaz, 6(Al 2 O 3 ,SiO 2 ) + A1F 3 + SiF 2 . Uwarowite, 3CaO, 2SiO 2 + Cr 2 O 3 ,SiO 2 . Chlorite, 2(RfO,SiO 2 ) + 2RO,A1 2 O 3 + 3HO. Ripidolite, 3(MgO,SiO 2 ) + 2MgO,Al 2 O 3 + 4HO. Opal, SiO 2 + xHO. Andalusite, Al 2 O 3 ,SiO 2 . Disthene, Al 2 O 3 ,SiO 2 . Cimolite, 2 Al 2 O 3 ,9SiO 2 + 6HO. Steinmark, 2Al 2 O 3 ,3SiO 2 + HO. Kaolin, Al 2 O 3 ,2SiO 2 +2HO. Warwickite, 3(Mg,Fe)O,TiO 2 . Pyro- phyllite, Al 2 O 3 ,4SiO 2 +HO. The following are decomposed by concentrated sulphuric acid : Magnesia Mica before the blowpipe loses its lustre, and melts in thin splinters only : gives the iron reaction with bj^tx beads : H = 2-5: occurs in thin leaves and scales: the moistened powder * R = Al,Fe. t R=Mg,Fe. E 66 Practical Guide to the Determination shows an alkaline reaction. Chlorite exfoliates before the blow- pipe, and turns white or black : yields water which has no acid reaction. Ripidolite the same, but melts somewhat more easily in thin splinters. Warwickite colours the bead with titanium, and the flame with boracic acid : streak brown. Hardness below 7 (i. e. less hard than quartz.) Talc becomes reddish when ignited with cobalt solution : exfoliates before the blowpipe : H= i : greasy to the touch : Bronzite and Hypersthene: lustre metallic on oo P oo (orthopinakoid) : brown or black : H=6. Chiastolite turns blue on ignition with cobalt solution : often recog- nisable by the crossed or tesselated appearance in a transverse section of a crystal (twin formation ?). Disthene turns white before the blowpipe, and then by ignition with cobalt solution finely blue : hardness nearly 7 : generally blue : flexible (if flexible at all, very rarely so). Cimolite yields water : exhibits a fine blue colouration when ignited with cobalt solution : grey : earthy. Steinmark yields water : ignited alone becomes white : with cobalt solution turns finely blue : H=2'5 : streak yellowish white : greasy to the touch. Kaolin yields water : friable : turns very blue when ignited with cobalt solution. Pyrophyllite yields little water : exfoliates before the blowpipe with vermicular movements, and swells up to a snow- white mass, much larger than the original assay : H = 1*5 : greenish. Opal suddenly heated before the blowpipe decrepitates and be- comes opaque : yields water in the closed tube : H=5'5 6-5. Hardness above 7: Cordierite: slightly fusible: trichroic. Staurolite : infusible before the blowpipe, but becomes darker : colours the bead with iron : the mineral powder is partially de- composed by sulphuric acid. Emerald and beryl become milk- white before the blowpipe : at very high temperatures edges of thin splinters are rounded with the formation of a colourless blebby slag. Euklase intumesces somewhat before the blowpipe, then turns white, and at a very high temperature can be fused into an enamel. Euklase contains six per cent, of water, which can be Of Minerals by the Blowpipe. 67 expelled at a white heat. Phenakite is unaltered before the blow- pipe : translucent. Zircon loses its colour before the blowpipe : lustre vitreous : H'= 7-5. Topaz: yellow varieties become rose- red before the blowpipe, but only after cooling : if boracic acid be fused on platinum wire until the flame is no longer coloured green, the addition of a little topaz powder restores the green tint to the flame. Andalusite turns blue when ignited with cobalt solution. Uwarowite, heated before the blowpipe, turns dark green, and lighter again on cooling : with borax gives green beads. Quartz : H = 7 : infusible before the blowpipe : lustre vitreous : resinous on fractured surfaces. IX. Minerals not comprehended in any foregoing group. Wolframocher, WO 3 . Scheelite, CaO,WO 3 . Cassiterite (Tin- stone), SnO 2 . Anatase, TiO 2 . Rutile, TiO 2 . Brookite, TiO 2 . ^schynite, TiO 2 ZrO 2 CaO CeO. Perowskite, CaO,TiO 2 . Pyrochlore, TaO 5 TiO 2 ZrO 2 CeO CaO FeO YO NaO -F. Xenotime, 3YO,PO 5 . Spinelle, MgO,Al 2 O 3 . Gahnite, ZnO,Al 2 O 3 . Diamond C. Wolfram (Fe,Mn),O,WO,. Corundum (Sapphire, Ruby, Emery, Smirgel), A1 2 O 3 . Diaspore, A1 2 O 3 ,HO. Yttrotantalite, TaO 5 YO CaO. Euxenite, TiO 2 YO UO CeO CaO. Polymignyte, TiO 2 ZrO 2 YO FeO CeO. Chrysoberyl, GO,A1 2 O 3 . Polykrase, NbO 2 TiO 2 ZrO 2 YO FeO. Lazulith (Klaprothine), 2(Mg, Fe,Ca)O,PO 5 + A1 2 O 35 3PO 5 , + 6HO. Columbite, (Mn,Fe)O,NbO 5 . Osmium-indium Graphite C. The following impart a wolfram colouration to the bead of microcosmic S2\t Wolframocher : sfa; lustre silky yellow: turns black before the blowpipe. Scheelite melts very difficultly: hydrochloric acid decomposes the mineral powder, leaving a yellow residue: 11=4-5: white, yellow, brown : streak white. Wolfram 68 Practical Guide to the Determination melts with difficulty into a magnetic globule with a crystalline exterior : dissolves in hydrochloric acid, leaving a yellow residue : colours the borax bead with manganese : H = 5*5 : streak brown to black. The following impart a titanium colouration to the bead of microcosmic salt: Anafase : infusible : H = 5*5 : indigo blue or black: streak grey. Rutile : infusible: 11 = 5-5: brown-red: streak yellow. Brookite : like anatase : crystallized in the prir- matic system. sEschynite : infusible, but inturnesces before the blowpipe and turns yellow : streak yellowish brown. H = 5*5. Perowskite : infusible : brown to black : streak greyish white : H = 5-8. Euxenite : infusible: H = 6*5 : lustre resinous: brown-black: streak reddish brown. Polymignyte : infusible. H = 6-5 : lustre metallic : iron-black : streak dark brown. Poly erase decrepitates before the blowpipe, but is infusible : glows when ignited, and is converted into a grey-brown mass: sulphuric acid dissolves it: black : by transmitted light yellowish brown : streak greyish brown : H = 6. Cassiterite : scales of tin are obtained by fusion with soda on charcoal : H = 6 5 : lustre adamantine : streak grey. Pyrochlore : reddish brown, blackish brown: turns grey before the blowpipe : the borax bead is coloured reddish yellow in the oxidizing, dark red in the reducing flame : H = 5 -5 : streak light brown. Xenotime: infusible: =4-5: translucent: lustre resinous:' brown: streak yellowish to flesh-red. Spinelle : infusible : very frequently in octahedra : H=8 : easily dissolved in microcosmic salt. Gahnite : like spinelle,, but almost insoluble in microcosmic salt. H = 7 8. Corundum : infusible : un attacked by acids : H = 9. Diaspore: infusible: heated in the closed tube, decrepitates Of Minerals by the Bloivpipe. 69 violently, splitting into little white flakes: yields water at a high temperature : H = 5-5 yellowish brown: streak white. Yttrotantalite infusible : in the closed tube yields a little water, which has an acid reaction, due to hydrofluoric acid : unaffected by acids : H = 5-5 : brown to iron-black ; streak greyish white. Chrysoberyl: infusible : unaffected by acids: H= 8*5: greenish: transparent. Lazulith : blue : loses its colour before the blowpipe, but is infusible, scarcely attacked by acids : but after ignition almost entirely dissolved by them : H = 5-5 : streak white. Columbite ; infusible : unaffected by acids : H = 6 : brown- black : lustre metallic : streak reddish brown to black. Osmium-Iridium : unchanged before the blowpipe : heated with nitre in the closed tube, gives the characteristic odour of osmium. H = 7. Graphite: burns before the blowpipe: H= i 2: iron-black to dark steel-grey : streak black : lustre metallic : ductile. Diamond : H = 10. UNIVERSITY 7O Practical Guide to the Determination TABLE, SHOWING THE HARDNESS AND SPECIFIC GRAVITY OF MINERALS, AND THE CRYSTALLOGRAPHIC SYSTEMS TO WHICH THEIR FORMS BELONG; TOGETHER WITH SOME OF THEIR MOST IMPORTANT SYNONYMS. Acmite H = 6 6-5. G = 3-5. Oblique. Adularia = Orthoclase. ^EschyniteH = 5-5. G = 5-1 5-2. Prismatic. Alabandine H = 4. G = 3-95 to 4. Cubic. Alum H 2 2*5. G = i '9 2. Cubic. Albite H = 6- 6-5. G = 2'6. Anorthic. Allanite =Orthite. AllophaneH = 3. G = r8. Amorphous. Alstonite H = 4 4-5. G = 3'65 37. Prismatic. AltaiteH = 3 3-5. G = 8'i6. Cubic. Aluminite = Websterite. Alumstone = Alunite. Alunite H = 3-5 4. G 27. Rhombohedral. Amalgam H = 3 3-5. G 137 14' I. Cubic. Amblygonite H = 6. G = 3 3*1. Prismatic. Ammonia alum H = 2 2-5. G = 175. Cubic. Amphibole H = 5 6. G = 2*9 3*4. Oblique. Analcime H = 5-5. G = 2-25. Cubic. Anatase H = 5-5 6. G = 3-83 3-93. Pyramidal. Andalusite H = 7-5. G = 3-1 3-2. Prismatic. Anglesite H = 3. G = 6-28, Prismatic. Anhydrite H = 3 3-5. G = 2^85 3*05. Prismatic. Ankerite H = 3-5 4. 6 = 3. Rhombohedral. Annabergite = Nickelbliithe. AnorthiteH =6. G = 27. Anorthic. Antigorite H = 2'5. G = 2'6. Doubtful. Antimonite H = 2. G = 4*6 Prismatic. Antimonnickel = Breithauptite. Antimonocher H = 4 5*5. G= 5*28. Compact. Antimonsilber = 3*5. G 9 '6. Prismatic. Antimony H = 3 3-5. G = 6'6. Rhombohedral. Antimony blende H = 1*5. G = 4*5. Oblique. Antimony bloom H = 2-5 3. G = 5 '6. Prismatic. Antimony glanz = Antimonite. Apatite H = 5. G = 3 '2. Rhombohedral. Apophyllite H = 4*55. G 2-36. Pyramidal. Argentine H = 2 2-5. G = 7 2 - Cubic. Arkansite = Brookite. Aragonite II = 3-5 4. G = 2-93 3-01. Prismatic. Arquerite H = 2 2-5. G = ID'S. Cubic. Arsenic (native) H = 3-5. G = 57 5-8. Rhombohedral. Arsenical antimony H = 3*5. G = 6*5. Rhombohedral. Arsenic bloom H = 1*5. G = 37. Cubic. Arseneisen H = 5 5-5. G = 6-887. Prismatic. Asbestus = Amphibole. Asbolane = Earthy Cobalt. Of Minerals by the Blowpipe. 71 Atacamite H = 33-5. G = 37. Prismatic. Augite H - 56. G = 3'2 3*4. Oblique. Axinite H = 6*5 7. = 3-3. Anorthic. Azurite = Chessylite. Baryte = Heavy Spar H = 33-5. G = 4-354-59. Prismatic. Barytocalcite H = 4. G = 3*6. Oblique. Bastite = Schiller Spar. Beryl H - 7-5 8. G=2'7. Rhombohedral. Beudantite H = 3-5 4-5. G = 44 3. Rhombohedral. Bieberite . G = i*92. Oblique. Binnite = Dufrenoysite. Biotite H = 2 2*5. = 2782-95. Rhombohedral. Bismuth (native) H = 2 2-5. G = 9-7. Rhombohedral. Bismuthine H = 2. G = 6*4. Prismatic. Bismuthite H = 4 4-5. G = 6'9- Amorphous. Bismuth ochre . G = 4*36. Doubtful. Bitter spar = Dolomite. Bittersalz = Epsomite. Blattererz H = I 1*5. G = 7-1. Pyramidal. Bleiglanz =: Galena. Bleihornerz = Phosgenite. Bleispath Cerussite. Bleivitriol = Anglesite. Blende H = 3-5-4. 6 = 4. Cubic. Blue vitriol H=: 2-5. G = 2'2. Anorthic. Boltonite H =- 5-5. G:=3. Prismatic. Boracite H = 7. G = 2*9. Cubic. Bornite H = 3. G = 5. Cubic. Borocalcite H = i. G = 1-65. Botryogen H = 2 2-5. G = 2. Oblique. Boulangerite H = 3. G = 6. Bournonite H = 2-5 3. G = 5-8. Prismatic. Boussingaultite Prismatic. Brauneisenstein = Limnite. Braunite H = 6 6-5. G = 4-8. Pyramidal. Braunstein = Pyrolusite. Breithauptite H = 5. = 7-5. Rhombohedral. Brewsterite H = 55-5. G = 2'2. Oblique. Brochantite H = 3-5 4. G = 3'9. Prismatic. Brogniartin H = 2-53. G = 27. Oblique. Bromite H = I 2. G = 5-8 6. Cubic. Bromsilber = Bromite. Bronzite H = 5 6. 0=3-5. Oblique. Brookite H = 6. G = 4-15. Prismatic. Brown hematite = limnite. Brucite H = 2. G = 2*3. Rhombohedral. Buntkupfererz = bornite. Bustanite H = 5-5. G = 3*2, variety of Rhodonite. Calaite H = 6. G = 2-62 3. Amorphous. Calamine H = 5. G = 4*4. Rhombohedral. Calcite H = 3. G = 2*69 2-75. Rhombohedral. Caledonite H = 2*5 3. G = 6-4. Prismatic. Calomel H y= 15. G = 6*5. Pyramidal. Carmenite = impure Redruthite (Dana). Oarnallite Massive, granular. 7 2 Practical Guide to the Determination Cassiterite H = 67. G = 687. Pyramidal. Celestine H = 3 3-5. G = 3-9. Prismatic. Cerite H = 5*5. G = 5. Rhombohedral. Cerussite H = 3-5. G 6-5. = Prismatic. Chabasie H = 4 4-5. G = 2'i. Rhombohedral. Chalkolith = Uranite Chalkophyllite H = 2. G = 2-5. Rhombohedral. Chalkopyrite = Copper Pyrites. Chalkotrichite = Cuprite. Chalybite = Spathose Iron. Chessylite H = 3-5 4. G = 3*8. Oblique. Chiastolite = Andalusite. Childrenite H = 4-5 5. G = 3-2. Prismatic. ChioliteH=4. G 2-85.'= Pyramidal. Chloantite = Weissnickelkies. Chlorblei = Cotunnite. Chlorite H = I I -5. G = 2'8 2-9. Rhombohedral. Chlorsilber = Kerate. Chonclrarsenite H = 3. Chondrodite H = 6*5. G = 3*15. Oblique. Chonikrite H = 3. G = 2-9. Compact. Christophite = variety of Zinc Blende. Chromeisenstein = Chromite. Chromite H = 5-5. G =4- 5. Cubic. Chromochre. Chrysoberyl H = 8-5. G = 37. Prismatic. Chrysocolla H = 2 3. G 2 2*2. Amorphous. Chrysolite = Olivine. Chrysolite = fibrous variety of Serpentine. Cimolite, very soft. G = 2-3. Amorphous. Cinnabar H = 2*5. G = 8. Rhombohedral. Clausthalite H = 2-53. G = 8-5. Cubic. Cobaltine H = 5-5. G = 6'2. Cubic. Cobalt bloom H = I -5 2. G = 3. Oblique. Collyrite H = 12. G = 21. Columbite H = 6. G = 5-3 6-4. Prismatic. Comptonite = Thomsonite. Copiapite H = 1-5. G = 2'I4- Doubtful. Copper H = 2-53. G = 8-58-9. Cubic. Copper pyrites H = 3-5 4. G = 4.2. Pyramidal. Coquimbite H = 22-5. G'= 2 - Rhombohedral. Cordierite H = 7 7-5. G = 2-62-7. Prismatic. Corundum H = 9. G = 4. Rhombohedral. Cotunnite G = 5*24. Prismatic. Covelline H = I'S 2. G = 3-8. Rhombohedral. Credherite H = 4-55. G = 4-9 5 Oblique. Cryolite H = 2-5 3. G = 2-95. Prismatic. Cuprite H = 3-5 4. G = 6. Cubic. Cuproplumbite H = 2-5. G = 6-4. Danburite H = 7. G = 2-95. Anorthic. Datholite H = 5-5. G = 2*9. Oblique. DecheniteH = 4. G = 5 '8. Massive. Desmine = Stilbite. Diallage H = 3-5 4. G = 3. Oblique. Diallogite H = 3-5 4-5. G = 3-5. Rhombohedral. Of Minerals by the Blowpipe. 73 Diamond H = 10. G = 3-5 3 '6. Cubic. Diaspore H = 5-5. G = 3-4 Prismatic. Diopside = transparent variety of Augite. Dioptase H = 5. G = 3*3. Rhombohedral. Disthene II = 5 6. G = 36. Anorthic. Dolomite H = 3'5 4*5. G = 2-9. Rhombohedral. Dufrenite H = 4. G = 3*5. Prismatic. Dufrenoysite { = ^ g = ft Earthy cobalt H = I 1*5. G 2'2. Amorphous. Edingtonite H = 4 4*5. G = 2"J. Pyramidal. Eisenapatite = Zwiselite. Eisenblau = Vivianite. Eisenglanz = Hematite. Eisenkies = Pyrite. Eisennickelkies H =3-54 G = 4-6. Cubic. Eisenocker = Rotheisenstein. Eisensinter H = 2 3. G = 2-22-5. Massive, &c. Eisenspath = Spathose Iron. Eisenvitriol H = 2. G = 1*85. Oblique. Elceolite = Nepheline. Electric Calamine = Smithsonite. Embolite H = 2. G - 5 '8. Cubic. Emerald H = 7 58. G = 2-7. Rhombohedral. Emery = variety of Corundum. Enargite H = 3. G = 4-4. Prismatic. Epidote H = 6-5. G = 33-5. Oblique. Epistilbite H = 3-5 4. G = 2'2. Prismatic. Epsomite H = 22-5. C = 17. Prismatic. Erdkobalt = Earthy Cobalt. Erinite H = 4-5 5. G = 4. Erythrme = Cobalt Bloom. Euchroite H = 3-5 4. G = 3*4. Prismatic. Eudyalite H = 5 5-5. G = 2-9. Rhombohedral. Euklase H = 7-5. = 3-3. Oblique. Eukolite = variety of Eudyalite (Dana). Eulytine H = 4-5 5. G = 5-96. Cubic. Eusynchite = variety of Dechenite. Euxenite H = 6-5. G = 4-6. Prismatic. Fahlerz H = 34. G = 4-55-2. Cubic. Faserzeolite = Mesotype. Faujasite H = 5. G = 1*9. Pyramidal. Fayalite H = 6*5. G = 4' I. Prismatic. Felspar H = 6. G = 2-55. Oblique. Fischerite H = 5. G = 2-46. Prismatic. Fluellite H = 3. Prismatic. Fluocerite H 4 5. G = 47. Rhombohedral. Fluor H = 4. G = 4-1. Cubic. Franklinite H = 66-5. G = 5' 1 - Cubic. Freieslebenite H = 2 -5. G = 6'2. Oblique. Gadolinite H = 6 -5. G = 4*3. Prismatic. Gahnite H = 7-58. G = 4-4. Cubic. Galena H = 2-5. G = 7.5. Cubic. Galmei = Calamine. Garnet H = 6-5 7-5. G = 3'l 4'3- Cubic. 74 Practical Guide to the Determination Garnsdorfite H = 1*5 2. G = 1-9. Amorphous. Gaylussite H = 2-5. G = 1*9. Oblique. Gelbbleierz = Wulfenite. Gelbeisenstein = Brown Hematite. Gehlenite H = 5-56. G = 3. Pyramidal. Geokronite = Schulzite. Gibbsite H = 3. G = 2-3. Doubtful. Gismondine, probably a variety of Phillipsite. Glanzkobalt = Cobaltine. Glaserite H = 2-53. G = 27 Prismatic. Glaskopf = Limnite. Glauberite = Brogniartin. Glaubersalz = Mirabilite. Glimmer = Mica. Gmelinite H = 4-5. G = 2- 1. Rhombohedral. Goslarite H=2 2*5. G = 2. Prismatic. Gothite H = 55*5. G = 4*124-37. Prismatic. Gold H = 2-53. G = 14-5519-1. Cubic. Grammatite = variety of Amphibole. Granat = Garnet. Graphite H = I 2. G = 2. Oblique. Grauspiessglanzerz = Antimonite. Greenockite H = 3'5. G = 4-8. Rhombohedral. Grossular = variety of Garnet. Griinbleierz = variety of Pyromorphite or Mimetite. Griineisenstein = Dufrenite. GymniteH=2 3*5. G=2'2. Amorphous. Gypsum H = I -5 2. G = 2 -3. Oblique. Haarkies = Millerite. Haidingerite H = 2 2*5. G = 2'8. Prismatic. Halotrichite = Keramohalite. Harmotome H =4*5. G = 2*392-5. Oblique. Hauerite H = 4. G = 3*5. Cubic. Hausmannite H = 5 5-5. G = 4-7. Pyramidal. Hauyne H = 5*56. G 2-25 2-5. Cubic. Heavy spar H = 3*3 3*5. G = 4'35 4*59- Prismatic. Helvin H = 66*5. G = 3-2. Cubic. Hematite H = 5 -5 6-5. G=5 5-3. Rhombohedral. Heteromorphite H = 2-5. G = 5 '6. Oblique. Heulandite H = 3'5 4. G = 2-2. Oblique. Hisingerite H = 3. G = 2*8. Amorphous. Hovelite = Sylvin. Hornblende = Amphibole. Hornsilber = Kerate. Humboldilith = Somervillite. Humite = Chondrodite. Hyacinth = variety of Corundum. Hyalite = Opal. Hydrargillite H = 2-53. G = 2 -35. Rhombohedral. Hydroboracite H = 2. G = I '9- Hydromagnesite H = 3*5. G=2*I4. Oblique. Hypersthene H = 6. G = 3 -4. Oblique. Idocrase H = 6-5. G = 3-353*45- Pyramidal. Ilmeriite H = 5 6. G = 4-665 -3 1 . Rhombohedral. lodite H = i. G = 5-5. Of Minerals by the Blowpipe. 75 lodsilber = lodite. Iridium H = 6 7. G = 22*8. Cubic. Jamesonite H==2 2-5. G = 5'6. Prismatic. Johannite H = 22 -5. G = 3'2. Oblique. Kainite H =2-5. Oblique. Kakoxene H = 34. G = 2-363 -38. Kaliglimmer = Mica. Kalisalpeter = Nitre. Kalksalpeter = Nitrocalcite. Kalkspath = Calcite. Kaolin. Karpholite H = 5 5-5. G = 2 -9. Prismatic. Karstenite = Anhydrite. Keramohalite H = I -5 2. G == I "6 I '8. Oblique. Kerate H = I 1-5. G = 5-55. Cubic. Keimes = Antimony Blende. Kieselkupfer = Chrysocolla. Kieselmangan = Rhodonite. Kieselwismuth = Eulytine. Kieselzink = Smithsonite. Kieserite H = 2-5. G = 2'5. Prismatic. Kilbrickenite H = 22-5. G = 6-4. Probable variety of Schulzite. Klaprothine = Lazulith. Klinochlor = Ripidolite. Klinoclase H = 2*5 3. G = 4-25. Oblique. Knebelite H = 6-5. G = 37. Massive, &c. Kobaltbluthe = Cobalt Bloom. Kobaltin = Cobaltine. Kobaltkies = Linneite. Kobaltvitriol = Bieberite. Kobellite G = 6-3. Kottigite H = 2 -53. G = 3 I . Oblique. Kollyrite = Collyrite. Korund = Corundum. Kreuzstein = Harmotome. Krokoit = Lehmannite. Kupfer = Copper. Kupferantimonglanz =. Wolfsbergite. Kupferglanz = Redruthite. Kupferindig = Covelline. Kupferkies = Copper Pyrites. Kupferlasur =. Chessylite. Kupfernickel H = 5 -5. G = 7 -5. Rhombohedial. Kupferschaum H = .1 2. G = 3. Prismatic. Kupferschwarze = Melaconite. Kupfervitriol =Blue Vitriol. Kyanite H=r 5. G = 3'6. Anorthic. Labradorite H = 6. G = 2 7. Anorthic. LanarkiteH = 2 2-5. G = 6'8 7. Oblique. Langite H 2 '5 3. G = 3 '5- Prismatic. Lanthanite H = 2*5 3. Pyramidal. Lapis-lazuli. Lasurstein = Lapis-lazuli. Laumonite H =3'5- G 2'4. Oblique. Lazulith H = 5 5-5. G = 3. Oblique. 76 Practical Guide, to the Determination Lead H = 1-5. G = 11-4. Cubic. Leaclhillite H =2 '5. G = 6-3. Prismatic. Leberkies = Magnesic Iron Pyrites. Lehmannite H = 2 '5 3. G = 6. Oblique. Leonhardite = variety of Laumonite. Leopoldite Sylvin. Lepidokrokite = variety of Gothite. Lepidolite H 2 3. G= 2'8 3. Prismatic or oblique. Leucite H = 5*56. G = 2 '5. Cubic. Leucopyrite = Arseneisen. Levyn H = 4 G = 2 'I. Rhombohedral. Libethenite H = 4. G = 3'7. Prismatic. Lievrite H = 5 '5 6. G =. 4. Prismatic. Limnite H = 5 5-5. G = 3*4 3 '9. Massive. Linarite H = 2 '5 3. G= 54. Oblique. Linneite H = 5*5. G = 4 "9. Cubic. Linsenerz = Liroconite. Liroconite H = 22-5. G = 2-9. Prismatic. Lithionite = Lepidolite. L6weiteH=2'5 3. G = 2-37. Pyramidal. Magnesia MicaH = 2 2-5. G = 278 2-95. Rhombohedral. Magnesite H = 4'5 5. G = 3. Khombohedral. Magneteisen = Magnetite. Magnetic Iron Pyrites H = 3 '5 4-5. G = 4'6. Rhombohedral. Magnetite H = 5-5 6-5. G=4'96 5-2. Cubic. Magnetkies = Magnetic Iron Pyrites. Malachite H = 3*54. G = 3754. Oblique. Malacolite =. variety of Augite. Manganese Epidote H = 6-5. G =3'4* Oblique. Manganglanz = Alabandine. Manganite H = 3'5~ 4- G = 4-3. Prismatic. Manganocalcite H = 4 5. G =3. Prismatic. Manganspath = Diallogite. MarcasiteH = 6 6*5. G = 4'65 4*9. Prismatic. Marcelin = Braunite. Marcylite = result of alteration of a copper sulphide. Mascagnine H = 2 2-5 G=r68 178. Prismatic. Matlockite H = 2-53. G = 7-2. Pyramidal. Meerschaum H = 2*5. G = 1*2 1.6. Compact, &c. Meionite = Scapolite- Melaconite H = 3. G = 6-25. Cubic. Melanglanz = Stephanite. Melanochroite H = 3 3-5. G = 5-75. Doubtful. Melilite = Somervillite. Mendipite H = 2-5 3. G = 7. Prismatic. Mengite H = 55-5. G = 5*4. Prismatic. Mercury Blende = Cinnabar. Mesotype = Natrolite. Miargyrite'H = 2*5. G = 5-3. Oblique. Mica H = 2-5. G = 2-83-1. Oblique. Millerite H = 3-5. G = 5-26-5-3. Rhombohedral. Mimetite. See Pyromorphite. Minium H = 2 3. G = 4'6. Pulverulent. Mirabilite H = I 52. G = 1-5. Oblique. Mispickel H=5'5. G = 6 6-3. Prismatic. Of Minerals by the Blowpipe. 77 Misy, massive, &c. Molybdanglanz == Molybdenite. Molybdanocker H = I 2. = 4*5. Prismatic. Molybdenite H = i 1-5. = 4*5. Rhombohedral. Monazite H = 5-5. G = 4*9. Oblique. Monradite H = 66-5. G == 3' 2 ^- -A- 11 altered Augite or Hornblende. Mosandrite H 4. G = 2*93. Muscovite = Potash Mica. Nadeleisensteiri = Gothite. Nadelerz H = 2 2*5. = 675. Prismatic. Nagyagite H=i 1-5. G=7*i. Pyramidal. Natrolite H = 5 5-5. G = 2'25. Prismatic. Natronsalpeter =z Nitratine. Nemalite probably an altered Brucite. Neolite H= i 2. G = 277. Massive, &c. Nepheline H = 5*56. G = 2'6. Rhombohedral. Nickelantimonglanz = Ullmannite. Nickelbliithe H = 2*5 3. G = 3*1. Oblique. Nickelglanz H = 5-55. G = 6'i. Cubic. Nickelsmaragd H = 3 3*25. G = 2 '6. Incrusting, massive, &c. Nickel wismuthglanz H = 4-5. G = 5 '13. Cubic. Niobite = Columbite. Nitratine H = 1-5 2. G = 2. Rhombohedral. Nitre H = 2. G = 1-9. Prismatic. Nitrocalcite, efflorescent. Nontronite G = 2-08. Nosean = variety of Hauyne. Oerstedite H = 5-5. G = 3-6. Altered Zircon. Okenite H = 4-5 5. G = 2'3- Prismatic. Oligoklase H = 6. G = 2-63274. Anorthic. Olivenite H = 3. G = 4-2. Prismatic. Olivine H = 6-5 7. G 3-4. Prismatic. Opal H = 5-5 6-5. G = 1-92-3. Amorphous. Ophite = Serpentine. Orangite H = 4-5. G = 5-35. Variety of Thorite (Dana). Orpiment H = I -5. G = 3*48. Prismatic. Orthite H = 6. G = 3-1 4-2. Oblique. Orthoklase H = 6. G = 2-53 2-59. Oblique. Osmium-iridium H= 7. G = 19-3 21*2. Rhombohedral. Palagonite H = 34*5. G = 2*4. Amorphous. Palladium H= 4-5 5. G=ir8 12-14. Cubic. Parisite H=4'5. = 4-35. Rhombohedral. Patrinite = Nadelerz. Pechblende = Pechuran. Pechuran H = 5-5. G = 6-46-71. Cubic. Pectolite H = 4 5. = 2-75 Oblique. Peganite H = 34. G * SB 2*5. Prismatic. Pennine = Ripidolite. Periclase H = 6. G = 3-75. Cubic. Perowskite H = 5*8. G = 4. Prismatic. Petalite H = 66 -5 . = 2-4. Oblique. Petzite H = 2-5 3. G = 8-31 8-83. Prismatic. Pharmacosiderite = WUrfelerz. Pharmacolite H = 2 2-5. G = 2-7. Oblique. Phenakite H = 7-5 8. G = 3. Rhorabohedral. 7 8 Practical Guide to the Determination Phoenicite = Melanochroite. Philipsite H = 4-5. G = 2'2. Prismatic. Phosgenite H = 3. G = 6' i . Pyramidal. Phosphorochalcite H = 4-55. G = 4 4'4- Prismatic. Pissophan = Garnsdorfite. Pistacite = Epidote. Plagionite H = 2 *$. 0=5-4. Oblique. Plattnerite G == 9*4. Rhombohedral. Pleonast = Spinelle. Polianite H = 6-57. G = 4' 8 5- Prismatic. Polybasite H = 2-5. G = 6'i. Rhombohedral. Polyhalite H = 3-5. G = 275. Prismatic. Polykrase H = 6. G = 5-1. Prismatic. Polymignyte H = 6-5. G = 4754-781. Prismatic. Polyspharite = Pyromorphite. Potash alum H = 2 25. G = 2. Cubic. Potash mica H = 2-5. G == 2-83-1. Oblique. Frehnite H = 67. G = 2 '92 3. Prismatic. Proustite = Rothgiiltigerz. Psilomilane H = 56. G = 3747. Massive. Pyrargyrite = Rothgiiltigerz. Pyrite H = 66-5. G = 5. Cubic. Pyrochlore H = 55-5. G = 4-2. Cubic. Pyrochroite H = 2-5. Pyrolusite H = 2 2*5. G = 47 5. Prismatic. Pyromorphite H = 3'5 4- G = 7- Rhombohedral. Pyrope = Garnet. Pyrophyllite H = I. G = 2'78. Prismatic. Pyrosmalith H = 4 4 -5. G = 3-1. Rhombohedral. Pyrosklerite H = 3. = 274. Prismatic. Pyroxene = Augite. Pyrrhotine = Magnetic Iron Pyrites. Quartz H = 7. G = 2-65. Rhombohedral. Quicksilberhornerz = Calomel. Rahtite = mixture of blende and other minerals (Dana). Rammelsbergite = Weissnickelkies. Realgar H = I -5. G = 3-5. Oblique. Redruthite H = 2-5 3. G = 5-7. Prismatic. Remolinite = Atacamite. Rhodizite H above 8. G = 3 '4. Cubic. Rhodonite H = 55*5. G = 3*63. Oblique. Ripidolite = Chlorite H = 2. G = 27. Oblique. Rock crystal = Quartz. Rock salt H = 2. G = 2'2. Cubic. Romeite H = 6-57. 4-7. Pyramidal. Rothbleierz = Lehmannite. Rotheisenstein = Hematite. Rothgultigerz H = 2 2-5. G=57 5-9. Rhombohedral Rothkupfererz = Cuprite. Rothnickelkies = Kupfernickel. Rothspiessglanzerz= Antimony Blende. Ruby = Corundum. RutileH=6'5. 6 = 4-224-3. Pyramidal. Sal-ammoniac H = I -5 2. 0=1-5. Cubic. Saltpetre = Nitre, H = 2. G == I '93. Prismatic. Of Minerals by the Blowpipe. 79 Sanidine = Orthoclase. Sapphire = Corundum. Sarkolite H = 6. G = 2 '5. Pyramidal. Sartorite = Sklaroklas. Sassoline H = 5'II. G=l*5- Anorthic. Scapolite H = 5 5-5. G = 27. Pyramidal. Scheelite H = 4-5. G =5-9 6-2. Pyramidal. Schilfglaserz = Freieslebenite. Schillerspar H = 3-5 4. G = 27. Schorl = Tourmaline H = 7 7-5. G = 3 3-3. Rhombohedral. Schorlomite H = 7*5. G= 3*8. Amorphous. Schrifterz = Sylvanite. Schulzite H = 2-5 3. G = 5 8 6-5. Prismatic. Schwefel = Sulphur. Schwefelkies = Pyrite. Schwefelnickel = Millerite. Schwerbleierz = Plattnerite. Schwerspath = Heavy Spar. ScoleziteH = 5 5-5. G = 2'2. Oblique. Scorodite H=3'5 4. G=3'2. Prismatic. Selenide of Copper, soft. Selenblei = Selenide of Lead = Clausthalite. Selenbleikupfer = Selenide of Copper and lead H = 2-5. G = 7 7-5. Selenide of Mercury H = 2*5. G = 7*1 7*37. Massive. Selenide of Silver H = 2-5. G= 8. Cubic. Selenium H = 2. G = 4-3. Selenquecksilber = Selenide of Mercury. Selenschwefel resembles Sulphur. Selensilber = Selenide of Silver. Senarmontite H = 3. G = 5-25. Cubic. Serpentine H = 3. G= 2-472-6. Doubtful. Silberblende = Rothgiiltigerz. Silberglanz = Argentite. Silberkupferglanz = Stromeyerite. Silver H = 2-53. G = lO'i II. Cubic. Sklaroklas H = 3. G = 5-4. Prismatic. Skolopsite H = 5. G = 2-53. Compact. Smaltine H = 5-5. G = 6-5. Cubic. Smaragd = Emerald. Smirgel nr Corundum. Smithsonite H = 5. G = 3*35 3*5. Prismatic. Soda H = II-5- G = 1*4- Oblique. Soda Alum H = 22-5. G = I '88. Cubic. Sodalite H = 6. G = 2*3. Cubic. Somervillite H = 55*5. G = 3. Pyramidal. Spargelstein = Apatite. Spartalite H = 44-5. G = 5-5. Rhombohedral. Spathose Iron H = 3-54-5. G =3-8. Rhombohedral. Speisskobalt = Smaltine. Spharosiderite = Spathose Iron. SpheneH = 5 5-5. 9 = 3-33-7. Oblique. Spiessglanzsilber = Antimonsilber. Spinelle H = 7*58. G = 3-5. Cubic. Spodumene H = 6 '5 7. G = 3-1. Oblique. Sprbdglaserz = Stephanite. 8o Practidil Guide to the Determination Stannine H = 4. G = 4'4. Cubic. Stassfurthite = Boracite. Staurolite H = 7 7-5. G = 3*6. Prismatic. Steinmark H I 2 '5. G = 2'5. Prismatic. Steinsalz = Rock Salt. Stephanite H = 2-2-5. G = 6 ' 2 - Prismatic. Sternbergite H = I 1-5. G = 4'2. Prismatic. Stiblite H = 4 5 -5. G = 5-2. Compact, &c. Stilbite H = 3-5 4. G = 2'i. Prismatic. Stilpnosiderite = Gbthite. Stolzite H = 3. G = 8. Pyramidal. Strahlkies = Marcasite. Strahlstein = Amphibole. Stromeyerite H = 2 '5 3. G = 6'2. Prismatic. Strontianite H = 3*5. G = 3 '6. Prismatic. Sulphur H = 1-5 2-5. G = 2 2T. Prismatic. Sylvan = Tellurium. Sylvanite H = 1*5-2. G = 5 73 -8 '28. Oblique. Sylvine H = 2. G = I -9 Cubic. Symplesite H = 2-5 G = 2*9. Oblique. Tachylite H = 6 '5. G = 2 '58. Amorphous. Talc H = I 1-5. G = 27. Prismatic (Dana). Tamarite = Chalkophyllite. Tantalite H = 6 6-5. G = 78. Prismatic. Tellurblei = Altaite. Tellurium H = 22-5. G =8*4. Rhombohedral. Tellursilber = Petzite. Tellurwismuth H = 2-5. G =8-4. Rhombohedral. Tennantite H = 4. G = 4-3 4-5. Cubic. Tephroite H = 5\ G = 4-1. Prismatic (Dana). Tesseralkies = Skutterudite. Tetradymite H = I 1-5. G = 7-5. Rhombohedral. Thenardite H = 2-5. G = 27. Prismatic. Thermonatrite H = 1-5. G = 1-5. Prismatic. Thomsonite H = 5 -5-5. G = 2-35. Prismatic. Thonmangangranat, = variety of garnet. Thorite H = 4-5. G = 4*6. Cubic and pyramidal (Dana). Thrombolite H = 3 4. G = 3-4. Amorphous. Thulite = Epidote. Tinkal H = 2- 2-5 G = 17. Oblique. Titaneisen = Ilmenite. Titanite = Sphene. TopazH = 8 G = 3-4 3'6. Prismatic. Tourmaline = 7 7 '5. G = 3 3 '3 Rhombohedral. Towanite = Copper Pyrites. Triphane = Spodumene. Triphylline H = 5. G = 3-6. Oblique. Triplite H = 5 5-5. G = 3-7. Prismatic. TritomiteH = "5-5. G = 4-16 --4-66. Cubic. Trona H = 2-5 " G = 2' I. Oblique. Tschewkinite H = 5-3. G = 4-5. Massive, &c. Tungstein = Scheelite. Turquoise = Calaite. Tiirkis= Calaite. Tyrolite = Kupferschaum. Of Minerals by the Blowpipe. 8 1 Uranglimmer = Uranite. Ullmannite H = 5-5-5. G = 6-2-6-5. Cubic. TTi-initP $ P art ly Torberite H = 22*5. G = 3-5. Pyramidal. lte ' ( partly Autunite H = 1-2. G = 3-1. Pyramidal. Uranochre, earthy, amorphous. Uranpecherz = Pechuran. Uwarowite H = 7-5 8. G = 3 '4. Cubic. Vanadinite H = 3. G = 6"8. Rhombohedral. Vauquelinite H = 2 '5 3. G = 5 '6. Oblique. Vesuvian = Idocrase. Vivianite H = 1-52. G = 2'6. Oblique. 'Volborthite H = 3. G = 3-5. Rhombohedral. Voltaite Cubic. Wad H = -5. G = 2-1 27. Amorphous. Wagnerite H = 55-5. G = 3. Oblique. WarwickiteH = 3 4. G 32. Oblique Wasserblei = Molybdenite. Wasserkies = Marcasite. Wavellite H = 3-5 4. G = 2-3. Prismatic. Websterite H = i. G = r6. Massive, &c. Weiss Arseniknickel = Weissnickelkies. Weissbleierz = Cerussite. Weissnickelkies H = 5-5. G = 7'l. Prismatic. Wernerite = Scapolite. Willemite H = 5-5. G = 4. Rhombohedral. Wismuth = Bismuth. Wismuthglanz = Bismuthine. Wismuthocker = Bismuth Ochre. Wismuthspath H = 4 4-5. G 7-67. Amorphous. Witherite H = 33-5. G = 4-24-4. Prismatic. Wohlerite H = 5-5. G = 3*4. Doubtful. Wolfram H = 5-5. G = 7-75. Prismatic. Wolframocher, earthy. Wolfsbergite H = 3-5. 0=4-7. Prismatic. Wollastonite H = 5. G = 2'8. Oblique. Wiirfelerz H = 2-5. G = 2-93. Cubic. Wulfenite H = 3. G = 6-36-9. Pyramidal. Xenotime H = 4'5 5- G = 4-39 4-55. Pyramidal. Yttrotantalite H = 55-5. G = 5-45-88. Prismatic. Yttrotitanite H = 6-5. G = 3'5 37. Oblique. Ytterspath = Xenotime. Zaratite = Nickelsmaragd. Zeylanite = Spinelle. Zink Blende H = 3-54. G = 4. Cubic. Zinkbliithe H = 2-5. G = 3-6. Massive, &c. Zinkenite H = 33-5. G = 5-3. Prismatic. Zinkoxyd = Spartalite. Zinkspath = Calamine. Zinkvitriol = Goslarite. Zinnkies H = 4 4-5. G = 4-4. Cubic. Zinnober = Cinnabar. Zinnstein = Cassiterite. Zircon H = 7-5. G =4 4-7. Pyramidal. Zoisite H = 67. G = 3*2 3-5. Oblique. Zwiselite H = 5. G'= 3-97. Prismatic. F INDEX. ACMITE, 63, 70 Adularia, 70 jEschynite, 67, 70 Alabandine 43, 70 Alum, 70 Albite, 63, 70 Allanite, 70 Allophane, 58, 70 Alstonite, 36, 70 Altaite, 33, 70 Aluminite, 37* 7 Alumstone, 37, 70 Alunite, 37, 70 Amalgam, 47, 70 Amblygonite, 53, 70 Ammonia alum, 34, 7 Amphibole, 63, 70 Analcime, 55, 60, 70 Anatase, 67, 70 Andalusite, 65, 70 Anglesite, 40, 70 Anhydrite, 36, 70 Ankerite, 70 Annabergite, 28, 70 Anorthite, 62, 70 Antigorite, 58, 70 Antimonglanz, 32, 70 Antimonite, 25, 32, 70 Antimonnickel, 32, 70 Antimonocher, 25, 32, 70 Antimonsilber, 31, 70 Antimony, 25, 32, 70 Antimony blende, 25, 32, 70 Antimony bloom, 25, 70 Antimony glanz, 70 Apatite, 53, 54, 70 Apophyllite, 60, 70 Argentite, 40, 70 Arkansite, 7 Aragonite, 35, 70 Arquerite, JO Arsenic, 25,70 Arsenical antimony, 27, 70 Arsenic bloom, 25, 70 Arseneisen, 27, 70 Asbestus, 70 Asbolane, 70 Atacamite, 48, 71 Augite, 63, 71 Axinite, 63, 71 Azurite, 48, 71 Baryte, 37, 71 Barytocalcite, 36, 71 Bastite, 71 Beryl, 65, 71 Beudantite, 71 Bieberite, 42, 71 Binnite, 71 Biotite, 71 Bismuth (native) 27, 45, 71 Bismuthine, 40, 71 Bismuthite, 40, 71 Bismuth ochre, 45, 71 Bittersalz, 34, 71 Bitter spar, 36, 71 Blattererz, 33, 71 Bleiglanz, 40, 71 Bleihornerz, 71 Bleispath, 71 Bleivitriol, 40, 71 Blende, 43, 71 Blue vitriol, 42, 71 Boltonite, 59, 71 Boracite, 37, 71 Bornite, 40, 44, 71 Borocalcite, 37, 71 Botryogen, 39, 71 Boulangerite, 32, 71 Bourn onite, 31, 71 Boussingaultite, 34, 71 Brauneisenstein, 39, 71 Braunite, 49, 7 1 Braunstein, 49, 71 Breithauptite, 32, 71 Brewsterite, 60, 71 Index. Brochantite, 42, 71 Brogniartin, 37, 71 Bromite, 47, 71 Bromsilber, 47, 71 Bronzite, 65, 71 Brookite, 67, 71 Brown hematite, 39, 71 Brucite, 37, 71 Buntkupfererz, 40, 71 Bustanite, 71 Calaite, 54, 71 Calamine, 50, 52, 71 Calcite, 35, 71 Caledonite, 71 Calomel, 25, 71 Carmenite, 40, 44, 71 Carnallite, 34, 71 Cassiterite, 67, 72 Celestine, 37, 72 Cerite, 58, 72 Cerussite, 46, 72. Chabasie, 60, 72 Chalkolith, 72 Chalkophyllite, 29, 72 Chalkopyrite, 72 Chalkotrichite, 72 Chalybite, 39, 72 Chessylite, 48, 72 Chiastolite, 72 Childrenite, 50, 72 Chiolite, 37, 53, 72 Chloantite, 72 Chlorblei, 72 Chloride of lead, 25 Chlorite, 60, 65, 72 Chlorsilber, 72 Chondrarsenite, 28, 72 Chrondrodite, 59, 72 Chonikrite, 60, 72 Christophite, 44, 72 Chromeisenstein, 38, 72 Chromite, 38, 72 Chromocher, 54, 72 Chrysoberyl, 67, 72 Chrysocolla, 48, 72 Chrysolite, 72 Chrysolite, 58, 72 Cimolite, 65, 72 Cinnabar, 25, 72 Clausthalite, 25, 72 Cobaltine, 27, 72 Cobalt bloom, 28, 72 Collyrite, 58, 72 Columbite, 50, 67, 72 Comptonite, 72 Copiapite, 39, 72 Copper, 48, 72 Copper pyrites, 40, 44, 72 Coquimbite, 39, 72 Cordierite, 65, 72 Corundum, 67, 72 Cotunnite, 25, 72 Covelline, 40, 44, 72 Crednerite, 48, 72 Cryolite, 37, 53, 72 Cuprite, 48, 72 Cuproplumbite, 40, 72 Danburite, 63, 72 Datholite, 55, 72 Dechenite, 46, 72 Desmine, 72 Diallage, 63, 72 Diallogite, 50, 72 Diamond, 67, 73 Diaspore, 67, 73 Diopside, 63, 73 Dioptase, 48, 73 Disthene, 65, 73 Dolomite, 36, 73 Dufrenite, 52, 73 Dufrenoysite, 27, 73 Earthy cobalt, 49, 73 Edingtonite, 73 Eisenapatite, 73 Eisenblau, 73 Eisenglanz, 38, 73 Eisenkies, 73 Eisennickelkies, 40, 73 Eisenocker, 39, 73 Eisensinter, 28, 73 Eisenspath, 73 Eisenvitriol, 73 Elceolite, 73 Electric calamine, 73 Embolite, 73 Emerald, 65, 73 Emery, 67, 73 Enargite, 73 Epidote, 63, 73 Epistilbite, 73 Epsomite, 34, 73 Erdkobalt, 73 Erinite, 28, 73 Erythrine, 73 Euchroite, 29, 73 Eudyalite, 57, 73 Euklase, 65, 73 Index. Eukolite, 57, 73 Eulytine, 45, 73 Eusynchite, 46, 73 Euxenite, 67, 73 Fahlerz, 27, 31, 73 Faserzeolite, 73 Faujasite, 55, 73 Fayalite, 57, 73 Felspar, 73 Fischerite, 54, 73 Fluellite, 73 Fluocerite, 54, 73 Fluor, 37, 73 Franklinite, 38, 73 Freieslebenite, 31, 73 Gadolinite, 59, 73 Gahnite, 52, 67, 73 Galena, 40, 73 Galmei, 73 Garnet, 50, 63, 73 Garnsdornte, 43, 74 Gaylussite, 35, 74 Gelbbleierz, 74 Gelbeisenstein, 74 Gehlenite, 59, 74 Geokronite, 27, 31, 74 Gibbsite, 54, 74 Gismondine, 55, 74 Glanzkobalt, 27, 74 Glaserite, 35, 74 Glaskopf, 74 Glauberite, 74 Glaubersalz, 34, 74 Glimmer, 74 Gmelinite, 55, 74 Goslarite, 43, 74 Gothite, 39, 74 Gold, 48, 74 Grammatite, 63, 74 Granat, 74 Graphite, 25, 67, 74 Grauspiessglanzerz, 74 Greenockite, 43, 74 Grossular, 62, 74 Griinbleierz, 74 Griineisenstein, 74 Gymnite, 60, 74 Gypsum, 36, 74 Haarkies, 74 Haidingerite, 37, 74 Halotrichite, 74 Harmotome, 60, 74 Hauerite, 43, 74 Hausmannite, 49, 74 Hauyne, 57, 74 Heavy spar, 37, 74 Helvin, 50, 74 Hematite, 38, 74 Heteromorphite, 32, 74 Heulandite, 60, 74 Hisingerite, 56, 74 Hovelite, 25, 74 Hornblende, 63, 74 Hornsilber, 47, 74 Humboldilith, 74 Humite, 74 Hyacinth, 74 Hyalite, 74 HydrargilHte, 54, 74 Hydroboracite, 52, 74 Hydromagnesite, 36, 74 Hypersthene, 65, 74 Idocrase, 63, 74 Ilmenite, 38, 74 lodite, 47, 74 lodsilber, 47, 75 Iridium, 75 Jamesonite, 31, 75 Johannite, 43, 75 Kainite, 34, 75 Kakoxene, 43, 75 Kaliglimmer, 75 Kalisalpeter, 35, 75 Kalksalpeter, 35, 75 Kalkspath, 75 Kaolin, 65, 75 Karpholite, 50, 75 Karstenite, 36, 75 Keramohalite, 37, 43, 75 Kerate, 47, 75 Kermes, 32, 75 Kieselkupfer, 75 Kieselmangan, 50, 75 Kieselwisnmth, 75 Kieselzink, 75 Kieserite, 37, 75 Kilbrickenite, 75 Klaprothine, 67, 75 Klinochlor, 75 Klinoclase, 75 Knebelite, 62, 75 Kobaltbliithe, 75 Kobaltin, 75 Kobaltkies, 75 Index. Kobalt vitriol, 42, 75 Kobellite, 31, 75 Kuttigite, 28, 75 Kollyrite, 75 Korund, 75 Kreuzstein. 75 Krokoite, 46, 75 Kupfer, 75 Kupferantimonglanz, 32, 75 Kupferglanz, 75 Kupferindig, 75 Kupferkies, 75 Kupferlasur, 75 Kupfernickel, 27, 75 Kupferschaum, 29, 75 Kupferschwarze, 75 Kupfer vitriol, 42, 75 Kyanite, 75 Labradorite. 62, 75 Lanarkite, 40, 75 Langite, 42, 75 Lanthanite, 54, 75 Lapis-lazuli, 57, 75 , Lasurstein. 75 ' Laumonite, 55, 75 Lazulith, 67, 75 Lead, 46, 76 Leadhillite, 40, 76 Leberkies, 76 Lehmannite, 46, 76 Leonhardite, 76 , Leopoldite, 25, 76 Lepidokrokite, 76 Lepidolite, 63, 76 Leucite, 62, 76 Leucopyrite, 27, 76 Levyn, 76 Libethenite, .48, 76 Lievrite, 57,' 76 Limnite, 38, 76 Linarite, 42, 76 Linneite, 40, 76 Linsenerz, 76 Liroconite, 29, 76 Lithionite, 76 Loweite, 34, 76 Magnesia mica, 65, 76 Magnesite, 36, 54, 76 Magneteisen, 38, 76 Magnetic iron pyrites, 43, 76 Magnetite, 38, 76 Magnetkies, 76 Malachite, 48, 76 Malacolite, 76 Manganese epidote, 50, 76 Manganglanz, 43, 76 Manganite, 49, 76 Manganocalcite, 50, 76 Manganspath, 76 Marcasite, 43, 76 Marcelin, 76 Marcylite, 42, 76 Mascagnine, 25, 76 Matlockite, 46, 76 Meerschaum, 58, 60, 76 Meionite, 76 Melaconite, 48, 76 Melanglanz, 31, 76 Melanochroite, 46, 76 Melilite, 76 Mendipite, 46, 76 Mengite, j6 Mercury blende, 76 Mesotype, 37, 76 Miargyrite, 31, 76 Mica, 63. 76 Millerite, 40, 76 Mimetite, 46, 76 Minium, 46, 76 Mirabilite, 34, 76 Mispickel, 27, 76 Misy, 39, 77 Molybdanglanz, 77 Molybdanocker, 53, 77 Molybdenite, 44, 77 Monazite, 54, 77 Monradite, 58, 77 Mosandrite, 60, 77 Muscovite, 77 Nadeleisenstein, 39, 77 Naclelerz, 40, 77 Nagyagite, 33, 77 Natrolite, 37, 55, 77 Natronsalpeter, 35, 77 Nemalite, 36, 77 Neolite, 58, 60, 77 Nepheline, 57, 77 Nickelantimonglanz, 32, 77 Nickelbliithe, 28, 77 Nickelglanz, 27, 77 Nickelsmaragd, 49, 77 Nickel wismuthglanz, 77 Niobite, 50, 77 Nitratine, 35, 77 Nitre, 35, 77 Nitrocalcite, 35, 77 Nontronite, 39, 56, 77 86 Index. Nosean, 57, 77 Oerstedite, 77 Okenite, 60, 77 Oligoklase, 63, 77 Olivenite, 29, 77 Olivine, 59, 77 Opal, 65, 77 Ophite, 77 Orangite, 58, 77 Orpiment, 25, 77 Orthite, 57, 77 Orthoklase, 63, 77 Osmium-iridium, 67, 77 Palagonite, 60, 77 Palladium, 77 Parisite, 54, 77 Patrinite, 40, 77 Pechblende, 77 Pechuran, 54, 77 Pectolite, 60, 77 Peganite, 54, 77 Pennine, 77 Periclase, 54, 77 Perowskite, 67, 77 Petalite, 63, 77 Petzite, 33, 77 Pharmacosiderite, 28, 77 Pharmacolite, 28, 37, 77 Phenakite, 65, 77 Phoenicite, 78 Philipsite, 55, 78 Phosgenite, 46, 78 Phosphorochalcite, 48, 78 Pissophan, 43, 78 Pistacite, 78 Plagionite, 31, 78 Plattnerite, 46, 78 Pleonast, 78 Polianite, 78 Polybasite, 27, 31, 78 Polyhalite, 37, 78 Polykrase, 54, 67, 78 Polymignyte, 67, 78 Polyspharite, 78 Potash alum, 34, 78 Potash mica, 63, 78 Prehnite, 60, 78 Proustite, 28, 78 Psilomilane, 49, 78 Pyrargyrite, 28, 31, 78 Pyrite, 43, 78 Pyrochlore, 67, 78 Pyrochroite, 50, 78 Pyrolusite, 49, 78 Pyromorphite, 46, 78 Pyrope, 63, 78 Pyrophyllite, 65, 78 Pyrosmalith, 78 Pyrosklerite, 60, 78 Pyroxene, 63, 78 Pyrrhotine, 43, 78 Quartz, 65, 78 Quecksilberhornerz, 25, 78 Rahtite, 40, 44, 78 Rammelsbergite, 27, 78 Realgar, 25, 78 Redruthite, 40, 44, 78 Remolinite, 78 Rhodizite, 78 Rhodonite, 50, 78 Ripidolite, 60, 65, 78 Rock crystal, 65, 78 Rock salt, 35, 78 Romeite, 32, 78 Rothbleierz, 78 Rotheisenstein, 39, 78 Rothgiiltigerz, 28, 31, 32, 78 Rothkupfererz, 48, 78 Rothnickelkies, 78 Rothspiessglanzerz, 25, 78 Ruby, 67, 78 Rutile, 67, 78 Sal-ammoniac, 25, 78 Saltpetre, 78 Sanidine, 79 Sapphire, 67, 79 Sarkolite, 79 Sartorite, 79 Sassoline, 52, 79 Scapolite, 57, 62, 79 Scheelite, 67, 79 Schilfglaserz, 31, 79 Schillerspar, 58, 79 Schorl, 62, 79 Schorlomite, 62, 79 Schrifterz, 33, 79 Schulzite, 27, 31, 79 Schwefel, 79 Schwefelkies, 79 Schwefelnickel, 79 Schwerbleierz, 46, 79 Schwerspath, 79 Scolezite, 55, 79 Scorodite, 28, 79 Selenide of copper, 79 Index. Selenblei, 79 Selenbleikupfer, 79 Selenide of mercury, 26, 30, 79 Selenide of silver, 30, 79 Selenium, 25, 79 Selenquecksilber, 25, 30, 79 Selenschwefel 25, 79 Selensilber, 30, 79 Senarmontite, 25, 79 Serpentine, 58, 60, 79 Silberblende, 79 Silberglanz, 79 Silberkupferglanz, 79 Silver, 47, 79 Sklaroklas, 27, 79 Skolopsite, 57, 79 Smaltine, 27, 79 Smaragd, 79 Smirgel, 67, 79 Smithsonite, 52, 79 Soda, 34, 79 Soda alum, 34, 79 Sodalite, 57, 79 Somervillite, 57, 79 Spargelstein, 53, 79 Spartalite, 52, 79 Spathose iron, 39, 79 Speisskobalt, 27, 79 Spharosiderite, 79 Sphene, 62, 63, 79 Spiessglanzsilber, 79 Spinelle, 37, 67, 79 Spodumene, 63, 79 Sprodglaserz, 79 Stannine, 40, 44, 80 Stassfurthite, 53, 80 Staurolite, 65, 80 Steinmark, 65, 80 Steinsalz, 80 Stephanite, 31, 80 Sternbergite, 80 Stiblite, 25, 32, 80 Stilbite, 60, 80 Stilpnosiderite, 80 Stolzite, 46, 80 Strahlkies, 43, 80 Strahlstein, 80 Stromeyerite, 40, 80 Strontianite, 35, 80 Sulphur, 25, 80 Sylvan, 80 Sylvanite, 25, 33, 80 Sylvine, 25, 80 Symplesite, 28, 80 Tachylite, 62, 80 Talc, 37, 65, 80 Tamarite, 29, 80 Tantalite, 50, 80 Tellurblei, 33, 80 Tellurium, 25, 33, 80 Tellursilber, 33, 80 Tellurwismuth, 33, 80 Tennantite, 80 Tephroite, 50, 80 Tesseralkies, 80 Tetradymite, 33, 40, 80 Thenardite, 35, 80 Thermonatrite, 34, 80 Thomsonite, 55, 80 Thonmangangranat, 80 Thorite, 58, 80 Thrombolite, 48, 80 Thulite, 80 Tinkal, 34, 80 Tinstone, 67 Titaneisen, 38, 80 Titanite, 80 Topaz, 65, 80 Tourmaline, 64, 80 Towanite, 40, 80 Triphane, 80 Triphyline, 50, 80 Triplite, 50, 80 Tritomite, 80 Trona, 34, 80 Tschewkinite, 57, 80 Tungstein, 80 Turquoise, 54, 80 Tiirkis, 80 Tyrolite, 29, 80 Uranglimmer, 81 Ullmannite, 32, 8 1 Uranite, 52, 81 Uranochre, 54, 81 Uranpecherz, 81 Uwarowite, 65, 81 Vanadinite, 46, 81 Vauquelinite, 46, 81 Vesuvian, 63, 81 Vivianite, 52, 8 1 Volborthite, 48, 81 Voltaite, 39, 81 Wad, 50, 8! Wagnerite, 53, 81 Warwickite, 65, 81 Wasserblei, 81 88 Index. Wasserkies, 81 Wavellite, 54. 81 Webster! te, 37, 43, 81 Weiss arseniknickel, 8 1 Weissbleierz, 81 Weissnickelkies, 27, 81 Wernerite, 81 Willemite, 52, 81 Wismuth, 8 1 Wismuthglanz, 81 Wismuthocker, 81 Wismuthspath, 45, 81 Witherite, 35, 81 Wohlerite, 62, 8 1 Wolfram, 38, 67, 8 1 Wolframocher, 67, 8 1 Wolfsbergite, 32, 81 Wollastonite, 57, 8 1 Wiirfelerz, 28, 81 Wulfenite, 46, 81 Xenotime, 67, 81 Yttrotantalite, 67, 8 1 Yttrotitanite, 53, 62, 81 Ytterspath, 8 1 Yttrocerite, 54, 81 Zaratite, 81 Zeylanite, 81 Zink blende, 43, 81 Zinkbliithe, 52, 81 Zinkenite, 31, 8 1 Zinkoxyd, 8 1 Zinkspath, 50, 8 1 Zinkvitriol, 43, 8 1 Zinnkies, 40, 44, 8 1 Zinnober, 8 1 Zinnstein, 81 Zircon, 65, 8 1 Zoisite, 63, 8 1 Zwiselite, 50, 81 Printed by Field & Tuer, 50, Leadenhall Street, London, E.G. (.3,784.) 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