U.C.D. LIBRARY CALIFORNIA STATE MINING BUREAU FERRY BUILDING, SAN FRANCISCO FLETCHER HAMILTON State Mineralogist San Francisco] BULLETIN No. 78 [May, 1918 Quicksilver Resources of California WITH A SECTION ON METALLURGY AND ORE-DRESSING By WALTER W. BRADLEY, E. M. COMPttWENTS Of FLETCHER HAMILTON STAU I^INEKALQGIST CAUFORXIA STATE PRINTING OFFICE SACRAMENTO 19 18 UCBtTORARY CONTENTS. Vuge LETTER OF TRANSMITTAL 7 PREFACE 8 Faut I. MINES AND GEOLOGY. Chapter 1. INTRODUCTION 9 Uses 9 Production and Prices 9 Present Economic Situation 12 Chapter 2. GENERAL GEOLOGY OF THE DEPOSITS AND THEORIES 07 ORE DEPOSITION 17 Geographical Distribution 17 Geologic Formations of the Middle Coast Ranges 17 Age of the Ore Deposits 18 The Franciscan Group , 19 Character and Age of European Quicksilver Deposits 21 The Ore Deposition 21 Form of the Deposits 23 Chapter 3. MERCURY MINERALS ; 25 Associated and Gangue Minerals 28 Chapter 4. CALIFORNIA DISTRICTS 30 MINES AND PLANTS, ALPHABETICALLY BY COUNTIES 35 •Alameda 35 Calaveras 35 Colusa 36 Contra Costa 41 Del Norte 41 El Dorado 42 Fresno 43 Glenn 46 Humboldt 46 Into 46 Kern 47 Kings _ 50 Lake 52 Los Angeles 70 Marin 70 Mariposa 71 Mendocino 71 Merced 72 Modoc 72 Mono 72 Monterey 73 Napa 76 Nevada 92 Orange 92 San Benito 93 San Bernardino 123 San Francisco 124 San Luis Obispo 124 San Mateo 149 Santa Barbara 150 Santa Clara 154 91579 4 CONTENTS. MINES AND PLANTS — Contimie-d. P.ise Shasta 168 Siskiyou 169 Solano 171 Sonoma ISl Stanislaus 197 Trinity 200 Tuolumne 203 Yolo 204 Part II. METALLURGY. Chapter 1. INTRODUCTION AND ACKNOWLEDGMENTS 206 METALLURGY OF MERCURY, OR QUICKSILVER 207 Furnaces 209 Retorts 210 Coarse-ore furnaces 220 Fine-ore furnaces '■ — 226 Losses ■ 241 Costs -- -_ 243 Percentage of extraction 245 Revolving- furnaces 247 Multiple-hearth type 250 Drying the ore 254 Condensers 255 Soot 271 QUICKSILVER ASSAYS 277 Chapter 2. CONCENTRATION OF QUICKSILVER ORES 286 The Author's Experiments 286 On tables, with water 294 By flotation, with oils 300 By solution, with an alkaline sulphide 321 PRACTICAL APPLICATIONS OF CONCENTRATION TO QUICKSILA'ER ORES IN CALIFORNIA 329 ESTIMATES OF CONCENTRATION COSTS 349 REDUCTION OF CONCENTRATES 350 ADVANTAGES OF THE ALKALINE SULPHIDE METHOD _ 351 CONCLUSIONS 352 Part III. BIBLIOGRAPHY ON QUICKSILVER. PART A: RE ASSAYS. CHEMISTRY, ORE-DRESSING, METALLl-RGY. ETC. 3.-)4 PART B : RE CALIFORNIAN OCCURRENCES ON GEOLOGY, MINERALOGY, AND MINE EQUIPMENTS 358 PUBLICATIONS OF CALIFORNIA STATE MINING BUREAU 363 INDEX 367 ILLUSTRATIONS. . Photographs P'ulletiu 27, "Quicksilver lie- sourees of California," 1!)();^, reprinted li)OS. p. 10. }*revious to -lune, lf)()4. a 'flask' of quicksilver contained 7().l pounds (the c(|iiivalent of 7") hhids. oi- Spanisli 'piiunds'). hut since that date 75 pounds, net. Photo No. 1. A shipment of 300 flasks of quicksilver from the New Idria Mine, San Benito County. 1850 81)000 1855 a c c: « ♦tlO TOOOP eaooo •100 5Q000 • 40 $80 40P00 »ro $60 3Q0O0 $50 i fO 20000 »» 120 IQOOO PLATE I. 1915 80000 7Q0OO ^ « 1. 4) <^ c eqooo §^ • no 50D00 $100 • 90 40,000 »80 $70 30000 SCO • 50 2Q0OO $40 $30 IQOOO $20 1850 I8S5 i9e Bu/M/h m 78 1). 10 38540 PLATE I. •5 "^ iRsn m.S5 I860 I86S 1870 1875 1880 IS 5 1390 I89S 1900 1905 1910 1915 V : III i ■■ ra Annua/ Price per F/ask. - / / — ; / " . ; _j__l ; ^ ! J 'ri 1 tj / ' 1 1 I 1 I 1 1 \ 1 \ i \ - " " [ ^'' / • IK) 1 ■ 1 1 fC 1 1 ! \ j ^ 'i', ■ IOC 50000 1 '', 1 , • W ^ ' ' J ; 1 •■ r 1 1 1 1 1 ' ' 1 1 ' 1 1 f , , 1 1 1 J I 1 \ • 80 WpOO , #70 « rs/ 1 I7D ' 1 \ 1 \ \ ' / \ 1 \ f s ) ^ t \ ^/ \ 1 /. \ _- I / s } ii ( ^ t ' \ > i \ / ^ 150 ZQCOa 140 ^^ 1 \ \ / \ / x,w^... vo ( H- ]' \ , — ' \ / \T I ^ y f ' — \ t , I , 1 / , ii , \ ' ( \ \ ' i' ^ ', / \ \ ■^ / \ . ' - - \ ' / 2 ■ -r V 1 / ' • ^ \ ,' ^ s > ^ 1 1 ^ 1 ^ . _,, \ / 1 Pr r.f f , ' s 1 / \ f ,_ - \ \ / iqpoo t20 \ / \ A — -■ - - - — — - - — - — — — - — - _ - - - — - - — — — — - — — - — — — — - — — — — — ■^ _ _ _ — — — — _ — _ — _ _ — — _- — — — — — — — — — — ^ - — — — — — — — — — :~ - - ~ - == - - - - - - - ~ - - - - ~ - - - - - - ~ - - - ~ d - ~ - — — - z — — — - - '■.n 855 ^~- ■^ 18 W J_ 1_ B65 J__ -'— le 70 ^— 1 B7S — II 80 ~T 965 IG so" — n le JT 19 io~ 1905 or 7S It i^rt Jint. 'H>*. ef 13 Sf^re Mining Bureau -t-l-M 1 i 1 1910 1915 Accompanying Bulletin /V5 78 I'KODL-CTIUN ANIJ PUKE OF QUICKSILVER IX CALIFORNIA, 1 S.'i II- ] H 1 7 p. 10 38540 QUICKSIIA'KI^ RESOURCES. 11 TOTAL QUICKSILVER PRODUCTION OF CALIFORNIA. Average ,' -Vverapre YlMV Flasks Value price per Year flask Flasks Value price ))er Hask la'jo 7.723 $768,052 .$99 45 1885 32,073 $986,245 $30 75 1851 27,779 1,8.59,248 66 93 1886 29,981 1,064,326 35 .50 1S52 20.000 1,166,600 .58 33 1887 33,760 1,430,749 42 38 1S58 22,284 1,235,648 55 45 1888 33,2.50 1,413,125 42 50 1S54 30,004 1,663,722 55 45 1889 26,464 1,190,880 45 00 lS5o 33,000 1,767,1.50 53 55 1890 22,926 1,203,615 52 50 1856 30,000 1,.549,.500 51 65 1891 22,904 1,036,406 45 25 1857 28,204 1,374,.381 48 73 1892 27,993 1,139,595 40 71 18.58 31,000 1,482,730 47 83 1893 30,164 1,108,527 36 75 18.59 13,000 820,690 63 13 1894 30',416 934,000 30 70 1860 10,000 .535,500 53 55 1895 36,104 1,337,131 37 04 1861 35,000 1,471.7.50 42 05 1896 30,7^5 1,075,449 34 96 1862 42,000 1,526,700 36 35 1897 26,691 993,445 37 28 1863 40,531 1,70.5,.544 42 08 1898 31,092 1.188,626 38 23 1864 47,489 2,179,745 45 90 1899 29,454 1,405,045 47 70 1865 53,000 2,4.32,700 45 90 1900 26,317 1,182,786 44 94 1866 46,.550 2.473,202 5.3 13 1901 26,720 1,285,014 48 46 1867 47,000 2,1.57,300 45 90 1902 29,552 1,276,.524 43 20 r^ 47,728 2.190,715 45 90 1903 32,094 1,33.5,9.54 42 25 1869 33,811 1,-551,925 45 90' 1904 *28,876 1,086,323 37 62 1870 30,077 1,725,818 .57 38 1905 24,655 886,081 35 94 1871 31,686 1,999,387 63 10 1906 19,516 712,-334 36 50 1872 31,621 2,084,773 65 93 1907 17,379 663,178 38 16 1873 27.642 2,220,482 80 33 1908 18.039 763,520 42 33 1874 : 27,756 2,919,.376 105 18 1909 16,217 773,788 47 71 1875 50,2.50 4,228,538 84 15 1910 17,665 799,002 45 23 1876 75,074 3.303,256 44 00 1911 19,109 879,205 46 01 1877 79,396 2,961,471 37 30 1912 20',60O 866,024 42 04 1878 __.- 63,880 2,101,6.52 32 90 1913 1.5,661 630,042 40 23 1879 73,684 2.194,674 29 85 1914 11,373 557.846 49 05 1880 59,926 1,857,706 31 00 1915 14,199 1,157,449 81 .52 1881 60,851 1,815,185 29 83 1916 21,427 2,003,425 93 50 1882 52,732 1,488,624 28 23 1917 24,382 2,396,466 98 29 1883 46,725 1,343,344 28 75 18&1 31,913 973,347 30 50 Totals - 2,137,728 $101,992,560 *Flasks! of 7.') pounds giac? -June, 19(U; of 7(iJ pounds previously. The accompanying- chart (Plate No. I), shows graphically th(- Huctiiations in the annual output by tlasks and the average annual prices. Previous to the high prices induced by the present war situ- ation, the high-water mark in the price of quicksilver in California was reached in 187-1 (the highest quotation being $118.55 per fiask), with $105.18 the average San Francisco figure for that year. This was pre- ceded by an average of $80.33 in 1873, and followed by $84.15 in 1875. The following year it dropped to $41.00. The low record sah'.s price was $25.25 in 1879, but 1882 was the lowest year, with an average of $28.23. A study of the production chart (Plate I) reveals several interesting features. It will be noted that the two highly productive periods, 1861-1869 and 1875-1883. were accompanied by low prices, though each was immediately pi'cccded by a sudden increase of price. The increased production at tlu' i)fcs('i]1 time is responding, in a meas- vire, to the stimnlus of the higher prices of the past three years; but, even at that, the production ha.s not yet attained tlie level of the [)erio(l QUICKSIIAKl^ KM'.SorKCKS. 11 TOTAL QUICKSILVER PRODUCTION OF CALIFORNIA. Ye;u- law 1851 1852 1858 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 18&1 FhlsUs Value Aveiafte Iirice 1)01" II ask Y.ar 7.723 27.779 20.000 22,284 30,004 33.(X10 30,000 28,204 31,000 13,000 10,000 35,000 42,000 40.531 47,489 53,000 46,550 47,000 47,728 33,811 30,077 31,686 31,621 27,642 27,/ 56 50,2.50 75,074 79,396 63,880 73,684 59,926 60,851 52,732 46,725 31,913 $768,052 1,859,248 1,166,600 1,235,648 1,663,722 1,767,150 1.549,.5O0 1,374,381 1,482,730 820,690 535,500 1,471,750 1.526.700 1.705,544 2.179,745 2,432,700' 2.473,202 2,1.57,300 2.190.715 1,.551,925 1,725,818 1,999,387 2,084.773 2,220,482 2.919.376 4.228,538 3,303,256 2,961,471 2,101,652 2.194,674 1.857,706 1,81.5.185 1,488,624 1,343,344 973,347 $99 45 66 93 58 33 55 45 55 45 53 55 51 65 48 73 47 83 63 13 53 55 42 05 .36 35 42 08 45 90 45 90 53 13 45 90 45 90 45 90 57 38 63 10 65 93 80 33 105 18 84 15 44 00 37 30 32 90 29 85 31 OO 29 83 28 23 28 75 30 50 1885 1886 1887 1888 1889 1890 1S91 1892 1893 1894 1895 1896 1897 1898 1899 1900^ 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 Totals .Xveiasp Flasks \'alne lince pel- flask 32,073 $986,245 .$30 75 29,981 1,064,326 35 .50 33,760 1.430,749 42 38 33,250 1,413,125 42 50 26,464 1,190,880 45 00 22,926 1,203,615 52 50 22,904 1,0.36.406 45 25 27,993 1,139,.595 40 71 30,164 1,108,527 36 75 30,416 934,000 30' 70 36,104 1,337,131 37 04 30,765 1,075,449 34 96 26,691 993,445 37 28 31,092 1,188,626 38 23 29,454 l,4ft5,045 47 70 26,317 1,182,786 44 94 26,720 1,285,014 48 46 29,552 1,276,-524 43 20 32,094 1,33.5,9.54 42 25 *28,'876 1,086,323 37 62 24.6.55 886,081 35 94 19,516 712,.334 36 50 17.379 663,178 38 16 18.039 763,.520 42 33 16,217 773,788 47 71 17,666 799,002 45 23 19,109 879,205 46 01 20',6OO 866,024 42 04 15,661 630,042 40 23 11,373 557,846 49 05 14,199 1,1.57,449 81 .52 21,427 2,003,425 93 50 24.382 2,396,466 98 29 2,137,728 $101,992,560 *riasks; of 7o iiounds sines .June, liiiil: of TfiJ pounds prsviously. The accompanyino- chart (Plate No. I), shows oraphically the tiuctiiations in the annual output by flasks and the averaj^e annual prices. Previous to the high prices induced by the present wai' situ- ation, the high-water mark in the price of quicksilver in California was reached in IST-t (the highest quotation being $118.55 per flask), witli $105.18 the average San Francisco figure for that year. This was pre- ceded by an average of $80.33 in 1873, and followed l\v $84.15 in 1875. The following year it dropped to $44.00. The low record sales price i was $25.25 in 1879, but 1882 was the lowest year, with an average of ! $28.23. A study of the production chart (Plate I) reveals several ' interesting features. It will l)e noted that the two highly productive periods, 1861-1869 and 1875-1883, were accompanied by low prices, though each was immediately preceded by a sudden iiiriTase of price. j The increased ))r()iln('ti()n at the pi'csnil lime is responding, in a meas- ure, to the stimulus of the higher pi-iccs of the past three years; but. even at that, the product i(»ii has not yet attained the level of the period \'2 CALIP'OKNIA STATE MINING BUREAU. 1892-11)04, a period of fair activity in (luantity of outi)ut l)ul of rela- tively low average prices. Some of the reasons for this failure to fully respond to this stimulus are discussed in succeeding })ai"ao-raphs. The changed economic status of quicksilver since the European war began led the writer to plot the second chart, herewith, (Plate II) of the average monthly San Francisco quotations since January, 1914, as pul)lislied by the Alining and Scientific Press. The weekly averages are also shown, for the period of the record peak in December, 1915- April, 1916. and the highest day's quotation during the third week in February, 1916. During that period there were some actual, ho)ia fidr sales made in San Francisco at close to the $300 mark per flask; and at the same time a figure of $340 per flask was quoted on the New Yor-k- market. The fall was as rapid as the rise, so that in spite of sueli previously unheard-of extremes, the average price for 1916 did not come up to the record of $105.18 for the year 1874. The chart (Plate II) shows most strikingly the sharp fluctuations in price. As San Francisco is the primary domestic market for quicksilver, the average yearly quotations on this market were, previous to 1914, used by the State ^Mining Bureau (and the U. S. Geological Survey, also) in calculating the value of the state's output of this metal. However, because in 1915-1917 there was considerable speculation in quicksilver by parties other than the actual producers (particularly in 1916 j, and tlie price changes often rapid, so that quotations did not always mean sales, we have for these years taken for the average 'value' the average actual sales as reported to the State Mining Bureau by the producers. This gave us an average value of $81.52 per flask for the year, 1915, instead of the $85.80 average of quotations ; $93.50 for 1916, instead of $125.89: and .$98.29 for ]9]7. instead of $106.33. PRESENT ECONOMIC SITUATION. Recent consular reports^ indicate that the output of the famous mines of Almaden, Spain, has decreased somewhat, and the expense of oper- ation increased. These mines are owned by the government and oper- ated under cinitract l)y lessees using convict labor. At the time of the above-mentioned report bids were being called for by the Minister of the Ti'easnry I'oi- new leases for Avorking the deposits, and additional cai)ital e\|)enditnre and exploration work were to be required. The cost of jn-oduction of quicksilver at Almaden is stated to liav(> incn^ased fi-om $8.29 i)er flask in 1900 to $15.22 in 1915. Fov two oi' thi-ee yeai's previous to th(^ outbreak of tiie Kuro[)t'an wai', our normal peace-times consumiitioii of (piicksilver in the United States was appro.xiiiuitely 25,000 flasks annually; and oui" domestic produc- T. S. CnminiTrn 'Ropoi-ts, No. 2!1S, Dec. L'O, IDIfi, p. 1079: Annual Soriis No. loB, .June 2:i, I'.M 7. p. :::'.. QUICKSILVER RESOURCES. 13 i->n i\i\i^ xj ,,^i,„ » ... ,.^o,. /IK'iJ..^ f!.,iwl,-« ill 1914, of isk })eace- 'ac'tiire of ying. and ion. Our price and ' importa- 3 in 1912 ; munitions ments cor- urces have )rotect our ated mines $8-$15 per lent-owned iues where iport duty ;ates, as ad number of are being- being tried, in spite of 1917. was the entire level of the 3s for those 5on for this ater capital 1 tonnages, 3 such large rtain. The i preceding 1912: diver industry producers are ind there were vill is required well-developed .•est costs, the during periods I * * * j^ larticularlv in fit. But "little 'McCaskev. H. D.. Mineral resources of the United States for l!i]2 : U. S. Geological Survey, Part I, p. 931, 191.3. 1914 1915 MyA«'y3,/,^^'.^/■J^J 1,15 ,3,^ - /jj JO- <»-«., jt^.t-j **-Sm ar «(v Ac ,•. /■« tif if' lib, jun M> *^ iff Oit n^ Or, J,- r,t ,1,, Af «»-*«-<-> ■'^ --• °-' *•■ *t ;*- /^i «<- 'i' •", Ji-v j^ A^ irg *■ in, Sk Jm- m -i *sao /JIO /»• fl4■ \ 7 \ y s - '31* ' ' -■ ' " '"'|9t5 J" ' *' «• ^^^^ A . '-^'^^ ,',,'_„ '^ " 1917 '* ,** _ . ,^„,,.j Monthly Average Quicksilver January, 191'1- Quotations at San Francisco, California, -Kebruary, 191S, Inclusive. QUICKSIIA'ER l.*KS(^T'RCES. 13 1i..u had fallen below 20,000 Masks per year (16,548 flasks in 1914, of wliieh California produced 11,373 flasks). Of this 25,000 flask peace- time consumption, nearly 50 per cent went into the manufacture of fulminate for explosive, detonating caps for mining, quarrying, and sporting arms ammunition as well as military ammunition. Our domestic output being inadequate, partly because of the low price and the lower average tenor of the ores mined, necessitated the importa- tion of several thousand flasks annually (6,300 in 1911; 1,100 in 1912; 2.280 in 1913; 8,200 in 1914). The enormous increase in munitions manufacture due to the war has obviously raised our requirements cor- respondingly. At the same time, imports from European sources have been, of course, curtailed, if not entirely cut off ere this. I The import duty of 10% ad valorem is not sufficient to protect our American miners against the competition of the convict-operated mines of Spain where quicksilver can be produced for as low as $8-$15 per flask, as noted above. Nor can we compete with the government-owned and operated mines of Idria, Austria, nor with the Italian mines where labor is also cheap. To give us proper protection the import duty should be at least 25% of the selling price in the United States, as ad valorum duties are based on cost values at the point of origin. The present improvement in the price has increased the number of operating properties in California. Lower grade ores are being worked ; and new methods of ore dressing and reduction are being tried, as discussed in the chapters herein on Metallurgy. But, in spite of the inducement of high prices, the output for the year 1917, was barely double that for 1914, both for California and for the entire United States; and, even at that, has not yet regained the level of the annual production for the years 1892-1904, though the prices for those years were relatively low. The most important, single reason for this is the lower grade of the ores, which in turn, requires a greater capital outlay for large-capacity equipment to handle commercial tonnages, and closer economy of operations. Capital hesitates to make such large investments where the maintenance of good prices is so uncertain. The conditions prevailing in the domestic quicksilver industry preceding the European war were well summarized by McCaskey^ in 1912: "Owing to the generally low prices prevailing, the domestic quicksilver industry- was not particularly prosperous in 1912. The great majority of the producers are operating old mines in which high grade ore is now rarely encountered, and there were no new rich ore shoots reported for the year. In most cases special skill is required to prevent the plants running at a loss. * * * Altliough each well-developed property is equipped with its own plant and presumahh- run at lowest costs, the margin of profit in many cases is so small upon low-grade ores that during periods of low prices the mining activity is likely to he considerably curtailed. * * * It is true that further improvements in metallurgical treatment, particularly in preventing furnace losses, sliould result in a better margin of profit. But little 'McCaskev, H. D., Mineral resources of the United States for i:)12: U. S. Geological Survey. Part I, p. 931, 1913. ]•_> CALIFORNIA STATE MINING BUREAU } f 1* 1S!,'2-1!)04. - lively low respond tc The eha began led the averao published are also si April 191 February, sales made the same t market. T previously come up tc II) shows As San ] average ye by the Stat calculating because in by parties . the price c^ sales, we \u actual sales This gave i instead of t $125.89 ; an Recent eo of Almader ation iucrea ated untlci- al)<)V('-iiicul i tlie Treasur eapi1;il cxpc cost of ])1-()(1 from -tS.-J!) For 1 wo () our noniial ,.. ...,^v, ui...i .-. v.mi.-,iciii|m mn oi (|MicKsii\'er in Tlie I uited Slates was api)i-o.\iniately 25,000 Hasks aunually ; and our dumi'slie i)i'oduc- 'T'. S. rommorce Rojiorls. No. 20S. Ttor. 20. lOin, )>. 1070: Annual Series Nn. 15B, .liilH' L'L'. I!il7, p. 3:{. QUICKSILVER RESOURCES. 13 linn had fallen below 20,000 liasks per year (16,548 flasks in 1014, oi" which CaliL'oriiia produced 11,373 flasks). Of this 25,000 flask peace- lime eonsuinption, nearly 50 {ht cent went into tlie manufacture of J'lilininate for explosive, detonating caps for mining, quarrying, and sporting arms ammunition as well as military ammunition. Our domestic output being inadequate, partly because of the low price and the lower average tenor of the ores mined, necessitated the importa- tion of several thousand flasks annually (6,300 in 1911; 1,100 in 1912; 2.280 in 1913; 8,200 in 1914). The enormous increase in munitions manufacture due to the war has obviously raised our requirements cor- respondingly. At the same time, imports from European sources have been, of course, curtailed, if not entirely cut off ere this. The import duty of 10% ad valorem is not sufficient to protect our American miners against the competition of the convict-operated mines of Spain where quicksilver can be produced for as low as $8-$15 per fla.sk, as noted above. Nor can we compete with the government-owned and operated mines of Idria, Austria, nor with the Italian mines where labor is also cheap. To give us proper protection the import duty should be at least 25% of the selling price in the United States, as ad valorum duties are based on cost values at the point of origin. The present improvement in the price has increased the number of operating properties in California. Lower grade ores are being worked ; and new methods of ore dressing and reduction are being tried, as discussed in the chapters herein on Metallurgy. But, in spite of the inducement of high prices, the output for the year 1917, was barely double that for 1914, both for California and for the entire United States; and, even at that, has not yet regained the level of the annual production for the years 1892-1904, though the prices for those years were relatively low. The most important, single reason for this is the lower grade of the ores, which in turn, requires a greater capital outlay for large-capacity equipment to handle commercial tonnages, and closer economy of operations. Capital hesitates to make such large investments where the maintenance of good prices is so uncertain. The conditions prevailing in the domestic quicksilver industry preceding the European war were well summarized by McCaskey^ in 1912 : "Owing- to the generally low prices prevailing, the domestic quicksilver industry was not particularly prosperous in 1912. The great majority of the producers are operating old mines in which high grade ore is now rarely encountered, and there were no new rich ore shoots reported for the year. In most cases special skill is required to prevent the plants running at a loss. * * * Although each well-developed property is equipped with its own plant and presumal)ly run at lowest costs, the margin of profit in many cases is so small upon low-grade ores that during periods of low prices the mining activity is likely to be considerably curtailed. * * * jt is true that further improvements in metallurgical treatment, particularly in preventing furnace losses, should result In a better margin of profit. But little 'McCaskev, H. D., Mineral resources of the United States for l'.l]2: U. S. Geological Survey, Part I, p. 931, 1913. 14 t'AMI'OHMA Sl'A'I'i; MIN'IXC lU'K'KAU. iiiil>iii\f lUfiit (Mil he made with low iiiaiket prices and uncertainty of ore supiilies. The domestic market for (|iiicksilvei- ai)i)ears to demand fiom liO.OOO to 25,000 llasks for consumption per annmn. The foreign market is not profitahle to American pro- iluceis in competition with large Kiiropean supplies availahle at lower prices. At low Iiriccs and nc^-mal output tlieie is little importation, but at liigh prices importation of foreign sui)plies reacts to curtail output l)y cutting prices to a low margin of profit. It would seem, therefore, that unless rich ore. workaljle imder favorable conditions at a large profit, be available, or industrial cliemistry find new uses for the metal and an increase in domestic demand i-esults thereb.v. tlic present producers must continue to operate inider sotnewhat \uifa vorable conditions, and new produceis anil small mines must compete witli established niine.--- and plants now operated presum- ably at minimum costs and witli special skill and knowledge of the art." Accui-jitc and reliable ccLst data as Id miniiiu- and rediielioii of (iiiick- .silvcr ill ('alifonna are ])i'a('l ieally iinobtaiuabk' cxcci)! in Ihe case of two or three of the hiriier operators. The others simply do not know what their per flask costs are, for lack of keepino' properly segregated aecoiints. TTowever, some approximations can l)e stated. In 1!)14, the 'operating costs' of the larger companies amounted to about >\^'.l'y per tiask of quicksilver ])roduced. This did not include interest, depreciation, amortization, etc. For the smaller operators the costs were relatively higher, and the market price having dropped to below $40 per flask ($37.50 average for July. 1914), but few properties were working. Present costs (January. 1918) are nearly doubled, evi'n for the larger operators, and probably more than doubled for the smaller fellows. Not only have the costs of supplies and labor increased all along the line, but it is extremely difficult to get or to keep skilled and reliable labor for either underground or reduction operations, in the quicksilver mines. This is in i)art due to the attractions offered by the extreme, high wages being paid at present in other lines, especially in the cop- l)er mines. This. too. is coupled with a decreasing efficiency of the laborers due to their increasing 'independence' and the spread of the ' r. \V. \V. " spirit among them. The continued maintenance of the present output is problematical, not only by reason of the foregoing circumstances, but from the stand- point of the uncertainties of the deposits themselves. AVith two excep- ticns (New Almaden mine, lowest level 2430 feet below outcrop; and Xew Tdi'ia mine, lowest level 1060 feet below outcrop). th(» deposits are ratlier shallow. Writing in 1887, Becker^ took a souuMvliat similar view: "I can not say that tlie I'utuie of the (nucksiUer industry nn the Pacific slope seems to me to be ver.v liop.'ful. Tlie troul)Ie is not in the lack of cinnabar, but in tile mechanical disintegration of the country effected by the Post-Neocomian iipluaval. To this are due the gi-eat irregularity of the deposits, the dissemination of t-innaliar in minute fissines, or as 'paints.' in tlie language of miners, and the small average size of the deep-si'ated veins. Hejiosits may soniewliere l)e found in firmer or less iissured rock, but tliere only can strong, simple fissure \eins be expected to prev;nl in depth. Sucli deposits are exceptional e\-erywliere. In the Almaden district [Spain] ore is known to occur at over .seventy points, but at onl.v one of them was the acciunula- tion great enough to svipply tlie wnrld with mei-cur.v for thousands of years. The 'Becker. (1. I'"., (Jeoldgv- cii the (|uicksil\er deposits of the Pacific Slope: U. S. Geol. Siirv.. Mon. Xlll. pp. 117-418. 1S8S. QnCKSlI.VKK KKSOrUCKS. 15 Santa Barbara, at Huancavelica [Peru], ton, was one of over fort.v known deposits m the s;ime district. Systematic and intelligent prospecting is even more needful in mines on the Coast Ran.ges of California than elsewhere, and the special attention i>r superintendents should be directed to a study of the tissure system. This will almost invaii.il)l>- be complex, and can be satisfactorily made out onl.v by daily study as the woi-k progresses. When a large p;irt of the mine is abandoned or closed, it is often impossible to find the key to the true distiiViution of the fissures and of the i>re chaml)ers which accompany them. Helpless groping, discouragement, and often abandonment of property which nrobal)l>- t-ontains treasures often follow. An increase of geological skill in the management of quicksilver mines would do much to offset the imfortunately capricious d!stril)ution of ore. Good civil and mechanical engineering is necessary, but not sufficient, to make the best of a quicksih'er mine, nor can occasional assistance suppl.v the place of enlightened daily study of geological structure. There is nothing novel in this warning, nor is there an.v prob- ability that so trite a piece of common sense will be heeded." This may .seem a .somewiiat pes.simi.stie view to take ef the situatiuii. Imt the record of auiiual production since that time shows that Becker was not very far wrong. The districts here, in which from a geological standpoint other and new deposits might be looked for. are almost en- tiiely lield now under agricultural patents, so that there is no induce- ment for the prospector to search for undiscovered ore bodies. The average tenor of the ores now being worked is extremely low. the larger operators handling materials which carry but 0.3',; -0.7% mer- cury. lender the circumstances, to allow at least a 25% margin of profit over total costs is decidedly conservative at the present time. With a production cost approximating $80 per flask for the 'average operator,' this would mean a minimum sales price of $100 per flask. We con- sldcv that at the present time a price of $100-$150 per flask i.s not unreasonable. Without a maintenance of these prices, the mainte- nance of the output is very uncertain.* One particular item of operation expense that has raised, in addition to the labor situation noted above, is that of fuel. Forstner^ showed figures in 1903 of from $3.50 per cord for pine to $5 per cord for oak, in the more favorably situated districts. Present costs are as much as 50% in excess of the above, depending on the locality. "Quicksilver furnaces are great consumers of wood, and even those mines which are located in well-timbered regions find the cost of their fuel steadily increa.sing. Only in exceptional cases can mines get their cordwood delivered for $3.50 per cord; generally the price is higher, in some cases double that figure. Hence most of the quicksilver mine managers are eagerly looking for a substitute for cordwood as fuel in their furnaces. Up to the present time, however, this has not been found." *Since the above was written, the Federal Government is taking 40% of the domestic quicksilver production at a specified price of $10.5 per flask. Producers are permitted to obtain whatever price they may from other consumers. Since which time, the quotations in the open market have ranged between $110 and $115 per flask. 'Forstner, Wm., Quicksilver resources of California: Cal. State Min. Bur., Bull. '1 , . pp. 10, et al.. 1903. 16 CALIFORNIA STATE JMIMXG BL'REAU. Since Forstner wrote the aliove a commercial substitute for cord- wood has been found in crude petroleum. Fuel oil lias now been in use for a number of years at the New Idria mine, San Benito County, and more recently adopted at New Almaden, Santa Clara County; at the Cloverdale aiul Ci-eat Eastern mines, Sonoma County; and for firing a 12-pipe retort at the Cuddeback mine, Kern County. Fuel-oil prices are at the present writing practically double what they were three years ago. Further details as to fuel and other costs are given else- where herein in the accounts of individual properties. QUICKSILVKK RESOURCES. 17 ChAI'TER 2. GENERAL GEOLOGY OF THE DEPOSITS AXD Theories of Ore Deposition. Geographical distribution. Tiit^ tliiit-ksilvei- distriet.s of California, which have thus far proven of C'onnnercial interest are mainly in the Coast Ranges, from Lake County on the north to Santa Barbara County on the south. Other, scattered occurrences, some of which have yielded commercial quan- tities of the metal, will be noted on the outline map (Plate III), as hcing in Del Xorte, Siskiyou, Trinity, Shasta, El Dorado, Kern, and San Bernardino counties. It will also be noted that the Sonoma-Lake- Colusa-Xapa occurrences form a more concentrated grouping than those to the south of San Francisco Bay. The southern string, though more scattered, includes the largest two single c[uicksilver producers of North America. New Almaden and New Idria. GEOLOGIC FORMATIONS of the MIDDLE COAST RANGES. The geologic formations of the middle Coast Ranges of California have been summarized by Lawson,^ as follows : "The micldle Coast Ranges of California, * * * j^j-g composed of many dif- ferent Ivinds of roclv, both igneous and sedimentary. The geologic history of the region is varied, including records of deposition, erosion, diastrophism, and volcanic eruptions, and the geologic structure is correspondingly complex and interesting. * * * * *^* * * "The oldest known rocks are certain quartzites, limestones, and crystalline schists, which are best exposed in the Santa Cruz, Santa Lucia, and Gabilan ranges. The age of these rocks is not yet known, but some of them are probably early Mesozoic and some are possibly Paleozoic. "These older i-ocks are intruded by the granitic and dioritic rocks of the ranges just mentioned and their extensions nortliward through Montara Mountain, the Farallon Islands, and the Point Reyes Peninsula as far as Bodega Head. "Upon the eroded surface of the complex of plutonic and metamorphic rocks rests the Franciscan group, composed chiefly of sandstones, radiolarian chert, foraminifei'al limestone, and lavas, associated with which are intrusive masses of spheroidal basalt and serpentinized peridotite. These rocks are widely distributed in the middle Coast Ranges, occurring notably in the Mount Hamilton and Mount Diablo ranges, about the Bay of San Francisco, and in areas north of the bay. "Upon the Franciscan group the Shasta series (Lower Cretaceous) rests in uncon- formable relation, and upon this group lies the Chico formation (Upper Cretaceous). These Cretaceous formations were once coextensive with the territory now occupied by the present Coast Ranges, and although removed by erosion over large areas where the Franciscan and older rocks now appear at the surface, they still constitute one of the largest elements in the stratigrapliy of the region. They are composed chiefly of shales and sandstones and in the ranges north of the bay have a measured thickness of between 5 and 6 miles. The Eocene rocks, which succeed the Chico, are much less widely distributed. They comprise two assemblages of sandstones and shales known as the Martinez and the Tejon formations, which near the Bay of San Francisco aggregate between 4.000 and 5,000 feet in thickness and in the area farther south are probably much thicker. Evidences of uncomformity between the Eocene and Cretaceous rocks have been observed in some places, but the discordance is not very pronounced. The fossil faunas of the two series are, however, very different. "Some strata referable to the Oligocene series have been observed and recorded, but the next great group of rocks is of Miocene age and is known as the Monterey group. The formations of this group have a wider distribution south of the Bay of San Francisco than those of Eocene age, and in some places they rest directly upon Cretaceous or older rocks, neither the Martinez nor tlie Tejon intervening. The most characteristic feature of the group is its content of bituminous shale, with which nearly all the oil of California is directly or indirectly associated. These shales alternate with sandstones, and the basal formation of the group is at many places conglomeratic. The group attains a thickness of several thousand feet, and in areas 'Lawson, A. C, U. S. Geol. Survey Geol. Atlas, San Francisco Folio (No. 193), pp. 3-4, 1914. 2-36.540 18 CALIFORNIA STATE MINING BUREAU. where it rests upon the Koeene the superposition is uneoniforniable. Tlie rotks of this group were doubtless originally deposited over the greater part of the area of the Coast Ranges from the Bay of San Francisco southward, but since their deformation and uplift they have been extensively eroded. Their remnants, however, form a considerable element of the stratigraphy of the region. "The next overlying formation, the San Pablo, is unconformable with the Monterey group and is mucli less widely distributed. In its southern ai-eas the discordance is strongly marked, but in some of the northern areas it is scarcely discernible. The rocks, which are chiefl.v marine sandstones that are locally intermixed with tuffs, are found on both flanks of the Coast Ranges. Their thickness in the best-known sections ranges from 1500 to 2000 feet. "Above the San Pablo unconformably, but in few places resting directly upon it, lies the Merced formation, a thick accumulation of marine sandstones, clays, and con- glomerates, which were laid down in Pliocene time in deep local troughs that sank as fast as the sediments were deposited. These basins of Pliocene marine deposits were apparently confined to the coastal side of the Coast Range region. On the inland side of that region similar geosynclinal troughs were developed to correspond- ing depths, in which accumulated fluviatile and lacustral sediments, constituting the Orinda formation. The Orinda and Merced formations are each more than a mile thick. Interstralified with the beds of both formations are layers of volcanic ash. "lipon the Orinda and Merced lie various lavas and volcanic tuffs alternating with lacustral clays, limestones, and sandstones. Of these lacustral formations, the Siesta (Pliocene) and the Campus (Pleistocene) are the most extensive. "The later Quaternary formations comprise marine shell beds, sands, and clays overlain by a thick deposit of alluvium that is rich in the bones of extinct Mammalia." AGE OF THE ORE DEPOSITS. The principal Calif ornian (piieksilver deposits are mainly in the Franciscan (Jurassic?) formations, with some also in the adjacent Knoxville (Lower Cretaceous). In the earlier geological writings,- the 'quicksilver series' was designated as being 'Neoeomian,' 'Xeocomian metamorphic,' 'Cretaceous metamorphic' and 'the ]\Ietamorphic Series.' Though occurring largely in these Jurassic-Cretaceous rocks, the age of the quicksilver mineralization is, in the majority of the deposits, certainly much later. In some eases, it is even as late as Quaternary. The comparative youth of quicksilver ore deposits, elsewhere, as well as in California,'' "is attested by the fact that many of them are found in sedimentary or volcanic rocks of Tertiary or Quaternary age. They are not confined to these rocks, however, and may, in fact, occur in rocks of any composition or age. Sandstones, shales, limestone, serpentine, granite, andesite, rhyolite, or basalt may harbor the ores, and the character of the surrounding rocks seems to have little influence on the value of tiie deposits. "The California belt contains ores in Jurassic, Cretaceous, and Tertiary sandstones and shale, in serpentine, and in late Tertiary or Quaternary basalt and andesite." At the Sulphur Bank mine in Lake County, the cinnabar deposits extend from the Knoxville sandstones and shales of the lower levels up through the overlying Quaternary basalt, and is, in fact, conceded to be still depositing* from the thermal waters so much discussed in pub- lished accounts of this mine. Whitney^ writing in 1865 says: "In regard to the geological position of the cinnabar deposits of California, it may be added, that this ore has been found by us in many localities, and in formations of nearly every age. It occurs in the Sierra Nevada and in the southern part of the State in strata of Triassic age, and on the eastern slope of the Sierra, probably in rocks of the same age. In the Coast Ranges it has been found in tlie Tertiary; but. as far as yet known, there are no large and valuable deposits except in the Cretaceous, in which position the localities which have been discovered, and where the ore is known to exist, in small quantity at least, are very numerous, extending in a line with the metamorphic Cretaceous from New Idria to Clear Lake." =See Whitney, Becker, Forstner and Lawson, in the various references noted under Bibliography. 'Lindgren, Waldemar, Mineral deposits, p. 461, 191."?. •Becker, G. F., Geologj- of the quicksilver deposits of the Pacific Slope : U. S. Geol. Surv. Mon. XIII, pp. 263, 270, 1S8S. ''Whitney, J. D., Geology of California: Geol. Surv. of Cal., Vol. I, p. 6S, 1865. QUICKSILVER RESOURCES. 19 Following- a discussion of the geology of the Europeati quicksilver deposits, Beck" states : "The greatest cinnabar deposits outside of Europe are those of California. * * * The deposits are mainly in the Coast Range, formed of folded metamorphosed Neocomian (Early Cretaceous) slates, with later intrusions of granite, quartz porphyry, andesite, rhyolite, and basalt. The tilting and dynamo-metamorphism of the Neocomian strata (.Aucella beds) took place as early as the Middle Cretaceous, and was repeated with accompanying volcanic eruptions. These eruptions, with which the quicksilver deposits are genetically connected continue into post-Pliocene time. "The deposits consist of very irregular veins, often as the chambered veins described by Becker, or forming stock-like bodies which extend laterally from the lode into the shattered or porous country rock." Becker' distinguishes three principal periods of igneous intrusions to which the ore deposition is genetically related: 1. pre-Pliocene, dur- ing which large masses of andesite were ejected, — a bluish-gray rock containing pyroxene and feldspar crystals embedded in a ground-mass of feldspar and magnetite. 2. A later andesitic eruption, near the close of the Pliocene, and belonging to a special group having traehytic physical characteristics, for which he proposes the name 'asperites. ' Rhyolite , probably younger than the andesites, is found near New Almaden and in the northwestern part of San Luis Obispo County. 3. Basalt eruptions belonging to the Quaternary and more recent -periods. THE FRANCISCAN GROUP. The age of the Franciscan formations has not yet been positively determined to the complete satisfaction of all geologists. Not only is the paleontological evidence extremely meager and contradictory, but the stratigraphic evidence is curiously self-contradictory and leads to a conclusion that few geologists may be willing to accept.^ There are exposures of the Knoxville series (Lower Cretaceous) which rest unconformably upon the eroded surface of the deformed and locally metamorphosed rocks of the Franciscan. These would indicate that the Franciscan is pre-Cretaceous. Franciscan rocks are found in por- tions of the southern Coast Ranges resting unconformably upon a com- plex that includes a granitic rock which can be traced continuously from the Coast Ranges around to a connection with the 'granite' of the southern Sierra Nevada. This granite is mapped and described as of post-Jurassic origin. It has also been observed that: 1. The sand- stones of the Franciscan group are composed very largely of granitic debris. 2. At no place has the granite been observed to be intrusive in the Franciscan. 3. The intrusive relation of the granite to the older rocks is clearly shown at many localities ; as, included fragments of these older rocks are common in the granite; but no Franciscan frag- ments have been thus found in the granite, "although the radiolarian «Beck, Richard, Die Lehre von den Erzlagorstatten : edition of 1903, translated by \\. H. Weed, The nature of ore deposits, vol. 2, p. 359, 1905. ■on. cit., pp. 152, et seq., 1888. »Lawson, A. C, U. S. Geol. Surv. Geol. Atlas, San Francisco Folio (No. 193), I'd CALIFOKMA STATE MINING BUREAU. cherts ;ii-(' well adapted lo presei'vatioii as inclusions, as is shown by tlie i'act that ihvy are common in the rocivs tliat intrude the Franciscan strata." 4. The pre-granitie rocks are generally metamorphosed, and consist chiefly of marbles, (luartzites, and schists, none of which resemble the Franciscan strata. 5. The local metamorphism in the I''''ranciscan is dne to basic in-uptives. and not o-i-anitic intrusions. These considerations lead to the c(>iiclusion that the F^'i-anciscan is post- granitic. This being" the case °"and accepting the view that the granitic rocks of the Coast Ranges are continuous Willi and of the same age as tlie granite of tlie Sierra Nevada, we must conclude that the Franciscan group is post-Jurassic. Tliis conslusion is clearly in conllict with that drawn from the fact that the Franciscan lies iinconformal^ly below the Knoxville (Lowei' Cretaceous). At present there appears to be no way of harmonizing the conflict without (1) either extending the geologic time at the interval between the recognized Cretaceous and the Juni.ssic, an extension that should not lie made without the justification of more thorougli in\estigation, oi- (2) assuming a peiiod of hatlio- lithic dexelopment in the Coast Ranges that was distinct from and older than that in the Sierra Nevada, an assumption that should also not be made without fuT-tlu'i- and fuller investigation." The Franciscan group (named from San Francisco, wliere it occurs in extensive exposures and from which it was tirst described'") com- prises.^^ "(1) a volimiinous accumulation of sedimentary formations, some of them clearly marine, others doubtfully so; (2) some Intercalated lavas of contemporary age; and (3) cei-tain crystalline schists produced by the metamorphism of both the sedi- mentary and the igneous rocks. "The formations of the Franciscan group are pierced at many points bj' igneous intrusi\es. which are so intimately associated with the sedimentary rocks, both as to age and as to distribution, that they constitute one of the most characteristic features of the group * * * these intrusives produced the metamorphism that formed the crystalline schists and so gave to the Franciscan group one of its most interesting features. "The sedimentary rocks of the group comprise (1) sandstones, conglomerates, and shales; (2) limestone; and (3) radiolarian cherts. The igneous rocks are (1) basalt or diabase, in many places having a strongly pronounced spheroidal or ellipsoidal structure, (2) periodotites., which have in general become thoroughly serpentinized. The dominant rock in the crystalline schists is glaucophane schist, which is so abundant in them that the schists as a whole are commonly referred to as 'the glaucophane schists,' although other varieties of crystalline schist are associated with them." Witli reference to these intrusives, Smith^- says : "There are in the Franciscan great masses of serpentine and numerous smaller areas of dyke rocks, mapped with the formation, though they ai-e intrusive in it, and therefore yovmger." It is a notable fact, and one of which the genetic connection to the quicksilver deposits is not yet definitely solved, that many, if not nearly all, of the mines in California are either at or near the contact of some of these serpentine bodies. Some are within the serpentine itself, but not the more important ones, at least so far as commercial development to date is concerned. •1-.awson, A. C. oj). cit. p. 7. '"Lawson. A. C, Sketch of the geology of the San Francisco Peninsula : U. S. Geol. ,ir ll^fl-. A.^n TJnn r^ri •? Q O - d 7 ft ISO"". •1-.awson, A. C. o]j. cit. p. 7. '"Lawson. A. C, Sketch of the geologv of the San Francisco Pt Surv. l.'Sth Ann. Rep., pp. 399-476. 189.^. "Lawson, A. C. I^ S. Geol. Surv. Geol. Atlas, San Francis p. 4. 1914. SCO Folio (No. 193). 1, J :m 4 . '-Smith, J. P., The geologic formations of California : Cal. State Min. Bur., Bull, p. 32, 191G. (^ncKSII.VER RESOURCES. 21 CHARACTER and AGE of EUROPEAN QUICKSILVER DEPOSITS. For purposes of comparison, the following snnnnaries relative to the deposits of Spain and Austria are here quoted. Beck^'' states that the deposits at Almaden, Spain, consist of three quartzite beds impreg'- nated witli cinnabar, tlie beds lieing of a mean thickness of 26 to 32 feet. Their richnes.s increased with depth to below 863 feet. (Lind- gren^^ in 1913 says: ''down to 1300 feet.") "The rocks consist of steeply upturned shales of Silurian and Devonian age, witli intercalated (luartzites. which weather out in steep rocky outcrops. The strata are often interrupted by dialiases and huge intercalations of igneous rocks." As to Idria, Austria :'^ "The deposits occur in an area of Alpine Triassic rocks, which have been disturbed at this locality in a very complicated way by a number of faults and overthrusts, and have been broken into a group of fault blocks, with northwest strike. * * * The quicksilver deposits of Idria consist only in small part of true veins, being mainly impregnations in country rock which are in part connected with large, well- detined fissures, though this is no longer demonstrable, owing to the removal of material from the workings. They appear to form stratiform deposits. In both fissures and impregnations the mineralogic character of the deposit is simple. Cin- nabar is the predominant ore. * * * xhe quicksilver ores, therefore, in the most important part of the Idria mines, have impregnated extensive masses of completely disintegrated rock, and have more or less saturated either highly porous or specially bituminous beds which acted as filters. The real channels of supply are not revealed. As the dislocations of the region are of Tertiary (probably Eocene) age it follows that the impregnation with quicksilver compounds is of very youthful age." With reference also to Idria, Lindgren^** states that "The ore bodies, which apparently do not extend below a depth of 1000 feet, in places follow the stratifications. * * * The ores are usually designated as 'impregnations' in shale or marls, but small veins and stockworks are also fovuid especially in the dolomite. The age of deposition is certainly post-Cretaceous, prob- ably Tertiary." It will be noted from the foregoing that these, the greatest two quick- silver deposits of the world, likewise their worthy namesakes in Cali- fornia, are relatively shallow in depth when we compare them with many cf the well-known gold or copper mines, the world over. THE ORE DEPOSITION. The earlier theory of the deposition of quicksilver ores (particularly cinnabar and native mercury) ascribed it to pneumatolitic action — that is, by vapors and l\v sublimation. Following the experiments of Christy^' and Becker,^* it is now generally accepted that the majority of such ore-bodies, if not all. are tlie result of hydro-thermal deposition; and that the hot springs which were the agencies for the deposition I'ither accompanied or followed immediately after periods of volcanic activitv or otlier io-neous intrusions. '='Beck, Richard, Die Lehr von den Erzlagerstatten, 1909, vol. 1, pp. 5iy-.522 ; edition of 1!)03 (pp. 35.5-366) translated bv W. H. Weed: The nature of ore deposits, vol. 2, pp. 350-351. 1905. See also: De Launay, Traite de Metallogenie, vol. 2, 1S93, pp. 672-6S0. "Lindgren, Waldemar: Mineral deposits, p. 465, 1913. '^Beck-Weed trans., op. cit. p. 352. '^op. cit. p. 466. ^"Christy, S. B., On the genesis of cinnabai- deposits: Am. Join-. Sci., 3d ser. \o\. 17, pp. 453-463. 1879. "*Becker. (r. T<\. Geology of the (luicksilvn- d.posits of the Pacific Slope: U. S. Geol. Suiv.. Moil. XIll. jip. 4i;i-).",ii. 17:'>-475. 22 CALIFORNIA STATK MINING BUREAU. According to Becker^" "In any one quicksilver bearing region, such as the Coast Ranges of California or inner Austria, it is difficult to avoid ascribing, a common source to the ore. This can not be the adjoining rocks, for they are most various. On the other hand, granitoid rocks seem everywliere to underlie the superficial, more heterogeneous formations, witliin a very few miles of tlie siiiface. The evidence is overwhelming that in many cases quicksilver oies were deposited from thermal spring.s of volcanic origin ; and the analogy between the deposits is so great that, in the absence of positive evidence of a different origin, the probabilities are in favor of the hypothesis of a similar origin for all of them. This does not imply tliat all quicksilver deposits are of the same age : those of Almaden for example, .si'em to Vie far older tlian most or perhaps any of the California deposits. Assuming that the quicksilver ores have been deposited from hot springs due to volcanism, it would seem that cinnabar might br classed as a volcanic emanation. In that case, however, one would look for this ore as a component of lavas and in craters. It is not certainly known to occur in this way, and if it exists in tliis association it must be very lare. It seems to follow that the volcanic springs must have leached the quicksilver from deep-seated rocks of very wide distribution, i. e., either from the granitic masses or from some unknown infragranitic rocks overlying the foci of volcanic activity. "To account for the limited ai'eas in which quicksilver occurs it must further be supposed either that the volcanic emanations are not everywhere charged with solvents for quicksilver, or that the rocks overlying the volcanic foci do not every- where contain quicksilver. Each of these suppositions involves a certain amount of irregularity in subterranean conditions. This, however, is not of itself a stumbling- block, since the mere existence of mountain ranges forbids the hypothesis of mii- formity within scores of miles from the surface." LindgTen-" suinniarizes similar views, in the following: "The uniform character of the quicksilver deposits points to a common genesis for all of them. The earlier belief that the ores were products of sublimation is generally abandoned, for the usual mode of occurrence, with minerals of aqueous origin, such as calcite, opal, chalcedony, and often barite. is decidedly opposed to such a view. Becker has pointed out that, as the character of the enclosing rocks has little influence on the deposits, they are most probably derived from a common, deep-seated source. Their structure indicates deposition near the surface, as does also the physiographic evidence at many places — for instance, where the ore appears in the crevices of Quaternary and little-eroded lava flows. "When it is noted that hot springs and volcanic surface flows are present in almost all regions of importance (except Almaden in Spain, Idria in Austria, and Nikitowka in Russia), and that cinnabar in considerable quantities is associated with undoubted spring deposits, or is actually deposited in hot springs, the argument becomes very strong indeed that such hot springs have formed the majority of the deposits. For the tew deposits tliat have no such clear connection with volcanic rocks — for instance, those mentioned above — the characteristic mineral association still holds good, and we are forced to the hypothesis that volcanism and hot-spring action are the causes of these also, though the products of the igneous activity may have failed to reach the surface and the hot springs may have subsided." The last statement in the above quotation would apply particularly to the Great Eastern mine in Sonoma County, California, the one not- able example in this state not visibly connected, either intimately or within a few miles, with volcanic or intrusive igneous roeks. Forstner^^ notes that : * * * "It is a striking fact that most of the jtromincnt mines north of S.an Francisco are in close proximit.\' to ba.saltic or relatively recent eruptions, as for instance : The Aetna mines, a basalt dike on the Silver Bow claim, and basalt in the Star claim : the Oatliill mine, a large basalt liodv in close vicinity to the mine ; the Corona and Twin Peaks mines, between the basalt of Oathill and that of the Howell Mountains: the Great Westei'n, a body of liasalt south and in close pi'oximity to the mine; the Sulphur Bank, basalt all around the mine: the Manhattan, surrounded b\ basalt to the east and nortli : the Boston, within half a mile of the basalt in th. Manhattan groun New Idiia district no definitely post-Tertiary igneous rocks can lie found, and those rock;^ which show indications of igneous origin are so altered that it reiiuires microscopic study of the rocks to determine whether they are altered eruptives or sedinientarles. In the Stayton district the country rock near the ore deposition is prominentl.\' basaltic, sometimes closely related to Becker's asperites. In San Luis Obispo County, in the Pine Mountain, Adelaide, and Oceanic districts, the scatt»>red exposm-es of igneous rock are of rhyolite. In Santa Clara Cotuit>- th«' (inly eruptive rock in ihe neighborhood of the ore deposits is rhyolite." "Becker, G. F., Quicksilver ore deposits: U. S. Geol. Surv. Min. Res. for 1892, p. 157, 18!)3. ^''Lindgren, Waldemar, Mineral deposits, p. 469, 1913. ^'For-^tner, William, Quicksilver resources of California: Cal. State Min. Bur.. Bull. 27, p. 21. 1903. QUICKSILVER RESOURCES. 23 Solubility of Cinnabar. After reeonntiug the experiments and experiences of a considerable number of investigators relative to the solubility and syntheses of the sulphides of mercury, Clarke'-- gives the following summary of their data : "It will be noticed that several of the syntheses of cinnabar involve the solubility of mercuric sulphide in solutions of alkaline sulphides or sulphydrates. On this sub- ject, apart from synthetic considerations, there is a copious literature. * * * -phe solubility of the mercuric sulphide manifestly depends upon considerations of tempera- ture, pressure, concentration, and the nature of the solutions employed, whether neutral salts, sulphydrates. or pob'sulphides. That mercuric sulphide is precipitated again by dilution has been shown by various oljservers, and Becker reports admixtures of metallic mercury in the sulphide thus thrown down. Here, then, we have a possible explantition of the frequent association of free inercury and the black metacinnabarite, although relief of pressure may be in some cases the equivalent of dilution as a precipitant. Organic matter, also, is a probable agent of reduction, by whicli the m.etal is liberated. Bituminous substances, such as idrialite, napalite, etc., are commonly associated with cinnabar ; and at the Phoenix mine in California an inflammable gas issuing from cracks in the rocks was found by W. H. Melville to have" 61. 49*^^ of CH4 in its composition. "The hydrocarbon CH,, it must be observed, is the first member of the paraffin series, to which some bitimiens belong. Becker has shown that hydrocarbons will precipitate mercuric sulphide from its alkaline solutions, first, probably, as metacinna- barite, which is afterwards slowly transformed into cinnabar. Another suggestion, due to A. Schrauf, who has studied the occurrence of mercury ores in Idria, is that the metal may be liberated by the direct dissociation of cinnabar vapor. He also ascribes the formation of some metacinnabarite to the action of hydrogen sulphide upon native mercury. Here again we are reminded that the same point may be reached by more than one road." The cliemieal characteristics of mercury are further discussed in the section of this present bulletin on metallurgy (see post). FORM OF THE DEPOSITS. The forms of the deposits vary iu much the same way that those of other metallic ores vary, with the hardness, porosity, etc. of the enclos- ing rocks, and with the extent and character of the fractures invaded by the ore-bearing solutions. Quicksilver ore bodies are found as fis- sure veins, reticulated veins, stockworks, the 'chambered veins' of Becker, impregnations, and placers. With reference to the form of the deposits. Becker-'' observes that it has often been asserted that quicksilver ores do not form deposits similar to those of the ores of other metals, but that he can find no evidence of this. With reference to chambered veins, he states r* "In many cases the deposits occupy zones of broken country rock and can not be regarded as simple veins. They may be divided into stocks, stockworks, etc., but nearly or quite ever>-where the various ore chambe.s are connected by fissures in such a way that tlie whole deposit may be better considered as consisting of fissures with excrescent chambers. I have suggested the term 'chambered veins' for such occur- rences as distinguished from simple fissure veins. In such deposits one may distin- guish lateral chambers and cap chambers according to the relations which the ore chambers bear to the main fissure. These terms have met the approval of some mining engineers. No better or more important instance of a chambered vein can be given than the deposits of New Almaden. "It is only under very exceptional circumstances that disturbances in the earth result in the formation of a single fissure. Much more frequently a system of parallel fissures is produced which, when filled with ore, forms a system of parallel veins. A 'Gangzug' or system of linked veins seems to occur in rocks which present somewhat irregular resistance under the action of forces such as would produce a system of parallel fissures if the rock presented uniform resistance." -Clarke. F. W., The data of geochemistry: U. S. Geol. Surv., Bull. 616, p. 667, 1916. "•■U. y. Geol. Survey., :\ron. XIII, p. 472. ='U. S. Geol. Surv., Min. Res. for lS'.t2, p, 158. 24 CALIF'ORMA STATK MINING BUREAU. While, as deseiilx'd above, the forms of quicksilver ore-l)odies do not dilfer essentially from the forms l\iio\vn and recognized in the cases of the other precions and semi-pi'ecions metals, they do differ in one very important feature — that of depth. As is noted in preeediug para- graphs-^, the most famous quicksilver mines of the woi-ld. Almaden, (Spain), Idria, (Austria), New Almaden and New Idria in California, have been worked to depths of only 1300', 1000', 2450' and 1060' respectively ; and with the exception of the first-named have all appar- entl.y bottomed their ore-])odies. In California, but few of the quick- silver mines have been worked to depths greater than 500 feet below their outcrops. The superficial nature of quicksilver ore dei)Osits is more fully realized, when we consider the fact that numy gold and copper mines, the world over, are being profitably worked at depths exceeding 2000 feet, and some even down to nearly 6000 feet. "■See p. 21. PLATE IV. I C. A. Coarse cinnabar crystals from Culver-Baer Mine, Sonornn County. California. v.. Minutely disseminated cinnabar in silica of recemented breccia, from Goldbank Mine, near Winnemucca, Nevada. C. Massive cinnabar from New Almadcn Mine, Santa Clara County. California. D. 24 38540 i quicksilver resources. 25 Chapter 3. MERCURY MINERALS. Although inei'cin-y is a component of more than twenty distinct min- eral species, there are bnt three of them that can be considered of com- mercial value — cinnabar, native quicksilver, and metacinnabarite. Of these, more than 95% of the world's output is obtained from the sul- phide, cinnabar. Cinnabar— Hg S. (Mercury 86.2%: sulphur 13.8%). Color, cochi- neal-red, often inclinini:- to brownish red and lead-gray. Streak, scar- let. Transparent to opaque. Luster adamantine, inclining to metallic when dark-colored, and to dull in friable and le.ss distinctly crystal- line or 'earthy' varieties. Hexagonal-rhombohedral-trapezohedral. Crystals usually rhombohedral or thick tabular in habit, according to Dana^ rarely showing trapezohedral faces ; also acicular prismatic. In crystalline incrustations, granular, massive ; sometimes as an earthy coating ('paint'). The writer has a hand specimen from the Culver- Baer IMine, Sonoma County, California, (see Plate IV) showing beau- tiful , transparent, somewhat tabular crystals, up to a quarter-inch across. Cleavage: prismatic perfect. Fracture subconchoidal, uneven. Somewhat sectile. IIardnes.s — 2.0-2.5. Specific gravity — 8.0-8.2. Hepatic Cinnabar or Liver Ore, contains some carbon aud clay; color and streak brownish. Cinnabar's most frequent occurrence, in California at least, is in metamorphic sandstones aud shales at or near the contact of an igneous rock (more often serpentine, which is an alteration form of the orig- inal rock), and in serpentine. It is generally conceded to have been deposited by solfataric waters carrying the sulphide in solution, im- pregnating the sandstones and filling cavities among the brecciated masses. Due to silification accompanying or following, much opal and chalcedony are often present. In some cases observed by the writer, notably the Goldbank ^Mine ore, which is described elsewhere herein, (see p. 288, post), apparently the cinnabar and the silica have been deposited sinuiltaneously. There is some question as to whether the earthy or 'paint' variety of cinnabar is not crypto-crystalline or even amorphous.- Specimens have been i^xamined under the microscope which showed no crystal form at 200 diameters magnification ; but pos- sibly a still higher magnification would resolve it. Investigators seem to be not all agreed that there is such a thing as an 'amorphous' min- eral.' •Dana, E. S.. Textbook of Mineralogy, 18519, p. .I'.ri. -See Becker, G. F., re Sulphur Bank, in U. S. G. S., Mon. XIII, p. 257. "See Am. Jour. Sci. XLI, 1916, pp. 490, 4!)1. 26 CALIFORNIA STATE MINING BUREAU. Metacinnabarite — the black sulphide of mercury, has the same chemical formula as cinnabar, Ilg S; but is grayish black in color; streak, black; and crystallizes in tlic isometric system, tetrahedral. It usually occurs massive, and often stated to be amorphous. It readily reerystallizes into cinnabar under certain conditions. Metacinnabar- ite was first reported from the old Redington ^Mine at Knoxville, Napa County, California, in 1872 and occurred there in considerable qiTan- tities; but has since been found at a number of other localitias in this State. It has a hardness of 3.0, and specific gravity of 7.8; being slightly harder and lighter than cinnabar. Native Mercury — Hg. It occurs to some extent in many quick- silver mines, accompanying cinnabar, not often in large quantities, but generally in disseminated fine liquid globules. In California it seems to be characteristic of the quicksilver ore deposits within certain ser- pentine areas, rather than those outside of the serpentine. The less important mercury minerals, occurrences of which have been noted in California are : Amalgam — a native alloy of mercury and gold was reported from Mariposa County by Sonnenschein,* and from Nevada County by Lindgren.^ The silver amalgams, Arquerite of Coquimbo, Chile (AgjoHg) and Kongshergite of Norway (Agj^Hg or Agy^ng) have not been reported as occurring in California. Calomel — Horn Quicksilver, mercurous chloride, HgoCL. Tetra- gonal. Color, white, gray, brown; Adamantine luster; hardness 1.0-2.0; specific gravity 6.48. Mercury 84.9%; chlorine 75.1%. Sometimes found in small, clear, colorless crystals, and in white crystal- line coatings in cinnabar districts. It has been reported from Napa and San Mateo counties." Coccinite — iodide of mercury, Hg I. Color reddish bro-wn. Re- ported with stibnite in Kern County, by J. D. Dana." Coloradoite — telluride of mercury, Hg Te. Rare. INIassive, granu- lar. Color, iron-black ; metallic luster ; hardness, 3 ; specific gravity, 8.63. Identified with other tellurides from the Norwegian Mine, Tuol- umne County by Hillebrand.^^ Eglestonite — oxychloride of mercury, Hg^CI.O. Isometric, in min- ute crystals. Color, yellowish brown, changing to black. Resinous to adamantine luster; hai'dness, 2-3; specific gravity 8.33. This rare mineral has been identified from San ^Mateo County, by Rogers."^ Its ^Sonnenschein, F., Zeits, der grfolog. Oe.scll.scli, Vol. VI. p. 243, 1854. See also Eaklf, A. S., Minoral.s of Califoniia : Cal. State Min. Bur. Bull. 67, p. l.S, 1914. "Liudgrt-n, Walilcmar, U. S. G. S.. Ann. Hop. 17, Pt. 2, p. 13. See also Eakle, A. S., op. fit. J). 1.0. «Cal. Statr- Min. Bur., Bull. fi7, p. r.7. 'Sv.stem of Mincialnny, 1S68. Sec aLso Kakle, A. S.. Minerals of California: Cal. Statp Min. Bur. Bull. 07, p. 61. "Ililli'lirand. Amcr. .lour. Sci., 1S09, Vol. VIII, p. 29.5. See also Eakle, A. S., Minoral.s of California: Cal. State Min. Bur. Bull. 67, p. 59, 1914. "Rogers, A. V., Amer. Jour. Sci., i:il1. ^'ol. 32, p. 4 8. See also Eakle, A. S., op. fit. p. 61. QUICKSILVER RESOURCES. 27 most noteworthy oei'urreiiec is in the Terlingua quicksilver district, Texas, in association with those other oxides and oxychlorides, kleinite, montroydite and terlinguaite, described hereinafter, and also calomel. Tiemannite — selenide of mercury, Hg Se. Isometric, tetrahedral. Oenerally massive. Color dark lead-gray ; streak black ; hardness 2.5 ; specifie gravity 8.30-8.47. Though this selenide is not common, some large masses of it have been found in association with cinnabar, not- ably in the Abbott Mine, Lake County, California, and in the Lucky Boy Mine, Piute County, Utah, the latter yielding quicksilver on a com- mercial scale for some time, in 1887, according to Becker.^° In Cali- fornia it has also been noted in Orange and Santa Clara counties," and in the Socrates Mine, Sonoma County. In addition to the above described mercury minerals, the following have been noted elsewhere but not as yet reported occurring in Cali- fornia : Ammiolite — a doubtful antimonite of mercury, with some copper, sulphur and iron, from Chile. An earthy powder color deep red or scarlet. Possibly antimonate of copper mixed with mercuric sulphide. Barcenite — related to Ammiolite, but contains no copper. Possibly antimonate of mercury. Rare. GuadaJcazarite — a sulphide of mercury similar to metacinnabarite with a portion of the sulphur replaced by selenium. Some zinc is stated also to be present, but probably not essential. From Guadalca- zar, Mexico. Kleinite — ^" possibly a mixture of mercury-ammonium chloride., NHgoCl in great preponderance, with an oxychloride and a sulphate or oxysulphate of mercury."^- From Terlingua, Texas, associated with eglestonite and montroydite. The original color of this mineral in the mine is almost canary yellow, but it deepens slightly to reddish yellow or orange on exposure to light, regaining the lighter shade after returning to the dark. Occurs mostly in small, distinct crystals, hexa- gonal, and showing a good basal cleavage. Luster adamantine to greasy. Hardness 3.5 ; specific gravity 7.98. Lehrbachite — a combination of selenide of mercury and of lead. Massive, granular ; specific gravity 7.8 ; color lead-gray to iron-black. From Lehrbach in the Harz Mountains, Germany. Levig-lianite — an iron bearing guadalcazarite. Living'stonite — a mercury-antimony sulphide, HgS. 2Sb2S3. Re- sembles stibnite in form. Color, lead-gray; streak, red; hardness 2.0; specific gravity 4.81. From Huitzuco, Mexico. Magnolite — mercurous tellurate, Hg Te. O4. "Becker, G. F., U. S. G. S., Mon. XIII, p. 385. "Gal. State Min. Bur. :^iill. 67, p. 47. '=Hillebrand, W. F. and Schaller, W. T., The mercury minerals of Terlingua, Texas; U. S. G. S., Bull. 405, p. 19, 1909. 28 CAUFOK'NIA STATK MINING BUREAU. Montr oydite — oxide ol' iiierciuy, IJgO containing niereury 92.6%, oxygen 7.4%. Occurs in prismatic crystals, some distorted, flattened, also worm-like forms. Color, from deep red almost l)lack, through dark orange to pale yellow. Luster vitreous, inclining to adamantine. Crystallization, orthorhombic ; cleavage perfect parallel to the braehypinacoid. From Terlingua, Texas, associated with eglestonite, kleinite and t(M'linguaite.^^ Onofrite — a sulphide of mercury with part of the sulphur replaced by selenium, Ilg (S,Se), containing up to 6.5% selenium. Sometimes associated with tiemannite. From San Onofre, ^lexico, and ^lai-ys- vale. Utah. Terlingnaite — oxyehloride of mercury, Hg. CIO. Color, "sulphur- yellow, olive green of varying shades, and brown, of which the sulphur- yellow probably changes to the olive-green."^* Hardness 2-3; specific gravity, about 8.7. Occurs as distinct crystals, as a crystalline crust. and as a yellow powder. The powder darkens on exposure to light. Cleavage perfect, parallel to I't^ar unit orthodome. From Terlingua. Texas, associated with eglestonite, kleinite and montroydite. Tocornalite — iodide of silver and mercury. Color pale yellow ; granular and massive. ASSOCIATED and GANGUE MINERALS. Tlie principal associated and gangue minerals in California (^uick- silver ores are: pyrite, marcasite, chalcedony, opal, dolomite, serpen- tine, quartz, petroleum and liitunuMis. Millerite, barite, magnesite, pyrargyrite, pyrolusite, stibnite, redingtonite, knoxvillite, native sul- phur and gold, have also been noted as occurring in association with certain cinnabar deposits in this State. The following table compiled by Becker^^ shows the principal min- erals and gangues, reported from nearly thirty of the most important mines and districts of both hemispheres, and is here given so that "the reader may .see at a Rlance both the frequency \vith which quicksilver is found in company with a sixen metalUc or earthy mineral and the particidar combination in a given di.strict. Tlie table is necessarily impeifect. since the reports a)'e in many cases laekinfi in fullness. The attempt is also made to distinguish the relative fre- quency of tile minerals noted so far as the reports enable one to Judse. » * * Blanks represent tlie absence of reports, for it would manifestly be impossible to demonstrate the absence of any mineral in any tleposit. * * • '■'Hillel))and & Schaller, U. S. G. S., Bull. 405. "Hillehrand & Schaller, op. cit., p. S5. '•"Becker, G. V.. Quicksilver ore deposits: U. S. Geol. Surv.. Min. Res. of U. S. for 1892, p. 14.-), 1893. QUICKSILVER RESOURCES. 29 MINERALS ASSOCIATED WITH QUICKSILVER ORES. p=prevalent; th-j inincrnl usually nccoiii|)iiiiics tlu' (>n> or is prcsviit in groat quantity in the mine. a = 8biinrlant: a oonsidviablv part of th;' ore is charactcriz'Ml by tile mineral. o=occasional: presence easily verified but quantity small. r rare: seldom found or present in very niiinite quantities relatively to quicksilver. Blanks indicate no report. Deposits i ;■"] 3 rt >% P5 fe ^ o q: '^I O 73 O O N P-. r-, Of U c t=< w Ebenezer. Kicking Horse Pass, B. C. Sulphur Bank, California o Manzanita Mine, California a Knoxville District. California o -Etna District, California a Xapa Consolidated Mine, Cali fornia a Great Eastern Mine, California.- a Great Western Mine. California., a Elephant Vein, California Xe^v Almaden Min°, California ' o Xew Idria Mine, California r Steamboat Springs, Nevada.— Guadalcazar, Mexico Huitziico, Mexico Huancavelica, Peru Mieres, Spain Santander, Spain .Almaden, Spain Deposits in Algeria Cape Corso, Corsica Vallalta, Italy Mt. Amiata, Italy o Rhenish Bavaria, Germany o Idria, Austria Copper nn'nes, Hungary Thihuthal, Transylvania .\vala, Servia Tagora and Gading, Borneo.. a r P P r r P P a P a P P a r r •• P P P r p o p P o a a r P ' P P P P i P P r r p a a P P a o o r r r o r a P P r a P a P P a a a a P P r P a P o a P P o a a P P P o P a r r o P P a a P a r a r r a 1 P o o o a o P r P P o P a P a "Gangiie minerals. — Whenever a quicksilver district has been at all fully reported upon it appears that either quartz (frequently associated with hydrous silica) or calcite accompanies the ore, and in the greater number of the cases both of these minerals are present in varying proportions. Not unusually dolmite also is present, as at New Almaden and at Idria. Ferrous carbonate is also met with. Relatively rare are barite and fluorspar. Barite is found in the Napa Consolidated, and thus far not elsewhere in California. It is also reported from near Lewiston, Utah, and from Guatemala. Barite occurs at Huancavelica. At Almaden a small part of the ore is accompanied by the same mineral, and Prof. Schrauf reports it from Idria. It was foimd in the deposits of the Palatinate and at Avala, as well as in Bohemia at Horowitz, in Hungary and in Borneo. Fluorspar is said to accompany cinnabar at Guadalcazar, La Tolfa in Italy, and at Idria. Gypsum, like fluorspar, is infrequent. I am not aware of its pi-esence in the California mines, though it is common enough in the regions surrounding some of them. It is one of the gangue minei'als at Guadalcazar and Huitzuco in Mexico, and at the Vallalta and Monte Amiata mines in Italy. A part of the gypsum is perhaps of secondary origin. "Boi-ax is interesting in association with cinnabar because generally recognized as an indication of volcanic oi-igin. It occurs at Sulphur Bank, Knoxville and Steam- boat Springs, but has not elsewhere been definitely recognized. It is probable that examination would reveal it in the hot springs of the Aetna district, and at the Manzanita. The solubility of Ijorax of course militates against its appearance, excepting where solfatarism is active." 30 california state mining bureau. Chapter 4. CALIFORNIA DISTRICTS. The general distribution of Ihc quicksilver deposits in California maj^ be noted on the outline map (Plate III). The two main sub- divisions are the groups north of San Francisco Bay, and those to the south. The other, outlying districts are each in a single county, and with the exception of a recent prospect in southeastern San Bernardino County, there are none south of Santa Barbara or the Tehachapi. Though the occurrence of cinnabar has been noted at several localities in the Sierra Nevada, at only one of these (-Bernard mine, El Dorado County) has there been any commercial production recorded. The main northern subdivision comprises the following districts : Mayacmas, Clear Lake, Suli)luir Creek, and Knoxville; with the Bella Union-La Joya. and the St. Johns-Hastings forming two somewhat isolated districts to the south of the others. The groups to the south of San Francisco Bay are separated by much longer intervals than those to the north, the principal districts being New Almaden, New Idria, northwestern San Luis Obispo County, and Los Prietos. A description of the general geology and topography of these more important districts, is here taken up in the order above named. Descriptions of other localities or subdivisions are taken up under the various counties. The individual mines and plants are discussed, by 'counties, in alphabetical order. MAYACMAS DISTRICT. The Mayacmas district is so called from the ^layacmas Range of which Mount St. Helena and Cobb Mountain are the most prominent points. It embraces parts of Napa, Lake and Sonoma counties, as will be noted hy the accompanying geological map (Plate V), reprinted from Bulletin No. 27 of the State ]\Iining Bureau. The quicksilver deposits are found on both sides of the range, the main lielt crossing it near Pine Mountain between Mount St. Helena and Cobb Mountain. The eastern section lies north of the range, and the western section, south of it. The following general description of the distrirt is given by Forstner:^ "The general tieiid of the licit is northwest. In it.s southeastern part, in Napa County, it is in very close pioxiniity to a region of very intense and probably pro- longeci eruptive action, covering Tertiai-y and post-Tertiary periods. The center of eruptions in this region was probably in the territory bounded by Mount St. Helena, the Twin Peaks (or Sugar J^oaves), and High Peak; the Hows have, however, spread over a large adjoining territory. Outside of this are found a great many other eruptive bodies in this district, of which the more prominent are : The basalt body on Oathill, some smaller ones in the tei-ritory of the .-T^tna Consolidated Company, and andesitic ei-nptive body northeast of Oathill. Pine Mountain, Cobb Mountain, and others. This district is hence a region of intense eruptive action. Large masses of lava h;ive covered parts of it. and while pai'tly eroded, extensive sheets of tufi cover at present pai-ts of it to a greater or less depth, and make it ver.v difficult to determine the limits of the cores of igneous rocks. The present deeply carved topography of the region is largely governed by the erosion of this capping. 'Forstner, William. Quicksilver Resources of California: Cal. State Min. Bur. Bull. 27. pp. .'55-39, 1903. V 3TAJq \ f. H V. «J?r i Ik tj ^ 3U3 V V averages from $2.50 to $3 Der cord. GEOLOGICAL MAP OF PORTIONS NAPA. SONOMA 8: LAKE COUNTY QUICKSILVER DISTRICTS. CALIFORNIA. ^HBir^ifi V'. ^'#'--- A-^-^ '- -<\\:?' 1903. .- ^ 1lnch= I Mile o; "'covntX ,A[ ^-— ^ ^'•^■"^-^llj:^/^ HUdreth ^ l<^ ■^, A /Andei>*on 1 t> "■■■- SoKuT— ^ ^J^!W-^;, S/^.^' (j^;^ ^^.. Cloverdale Mine. No, Name of Mine, 10 — Geyser, Sulphur. 11 — Black Bear Group. 12— Pluton Den. 13— Clyde. 14 — Culver — -Baer Group. 15 — Rattlesnake. 16— Tunnel Site, i 17 — Incandescent. > 18— Almaden. J No. Name of Mine. 19— Mate. 20 — Eureka Nos. I and 2, 21 — Captain. 22— 23— Cedar. 24— Quicksilver. ( Crow 25 — Queen Group. 26 — Lookout, i 27 — Diamond. \ 28 — Mercury. Eureka Con. vn Point. Q. Mining Co. No. Name of Mine. 29 — Socrates. 30 — Mercury, 31 — Great Northern, 32— Hope. > 33— Hope. \ ' 34 — Denver. 35-1 36 — > Lucky Stone Group, 37— i 38— Hurley. Point Q. Mining Cc. No. 39— Pacific. 40 — Hercules. 41 — Sonoma. 42— 43— 44— 4S — Pontiac. 46 — Pontiac. 47 — Boston. 48 — Empire. Name of Mine, Crown Point Quick- silver Mining Co. No. Name of Mine. 49— Double Star. 50— Occidental. 51 — Hcaldsburg. 52— Edith. 53 — Cinnabar King Group. 54 — Eugenie. I 55 — Maud. |- Bacon Con. 56 — Dragon, 1 5 7 — Napa. Reprinted from Bulletin No. 27. DISTRICT. oup. I Con. No. Name of Mine. 58 — St. George. 1 59— Golden Gate. - Bacon Con, 60— Eagle. ) 61— Helen. 62 — Young America. 63 — Chicago. 64— Wall Street. 65 — Jewess. 66 — Middletown. 67 — Middletown. No. 68 — Gem. 69 — Great Eastern. 70— Hope. 71 — Liverpool Con, 72— Eureka Con. 73 — Eureka Con. 74 — Eureka Con. 75 — Eureka Con. 76 — Eureka Con. 77— Eureka Con. Name of Mine. No. Name of Mine. Great Western. -Standard Q. Co. Napa Consolidated. 78— Eureka Con. 79 — Eureka Con. 80 — Eureka Con. 81 — Contention. 82 — Minnesota. 83 — Manzanita. 84— Mercury. 85— Bone. 86— Fanny. > Napa Consolidated. Napa Consolidated. No. Name of Mine. 87— Osceola. 88— South Side. 89— Corona. 90 — Napa Con. 91— 92— Beechcr. 93 — New Granada. 91 — Twin Peak. 95— Twin Peak. No. Name of Mine. 96— Ida Easly. 97 — Old Discovery. 98— Twin Quart*. 99^Good Enough. 100 — Silver Bow. \ 101 — Phoenix. I 102— Red Hill. { . . - 103-Starr. ( A'^'"* ^° 104 — Pope. I 105 — Washington. / n qAM JAOlDOJOao to evioiTHoq s.'3 a>IAJ d8 AM0I408 .A^ATI piHTSia aaYdi8:aoiijg T ii C n li AIVTHO^JAO .eoei .^' y. Bull. 27, np! ^»'?i-^ .U^3flUS OmUlM 3TAT8 ^ 1 I I I III I I I, V^l pp. 35-39, 1903. QUICKSILVER RESOURCES. 31 "The older rocks are mainly represented by sandstones, sometimes nearly unaltered, sometimes thoroughly altered into schists, with all intermediary gradations. Serpen- tine is very prominent, mostly a hard, dry variety, in places disintegrated and pul- verized by weathering, showing as large bare spots along the ranges. Even where not bare, "the serpentine can be detected at a distance by a sparse vegetation, while on the balance of the surface a very close growth of brush or grass is found. The relation of the serpentine to the (luicksilver deposits is not clear. Most of these are associated with, or in close proximity to, serpentine ; but others, like those at Oathill and Cloverdale. are entirely away from the serpentine and where the serpentine is very prominent and continuous over a certain width, no deposits of any value have lieen found ; as. for instance, between Oathill and the Mirabel around the head of l^ucksnorter Creek ; on the ridge between Bear Creek and Dry Creek ; on the main ridge between the headwaters of Dry Creek and Briggs Creek. Neither are workable quicksilver deposits found in the serpentine. "Where serpentine is associated with any deposits, tliese are always contact deposits, while 'both the Oathill and Cloverdale mines are in the sandstone. "The ciuicksilver deposits appear from their association witli tlie opaline rock, which is presumably an alteration product of serpentine by silicification, to be related to the serpentine to a certain extent. The fact that, where it is very wide, no paying deposits have been found, would indicate, however, that either the sandstones contain the primary disseminated metal, which is concentrated through some process of secondary concentration, or else in the large bodies of serpentine the concentration took place only in those parts affected by contact metamorphism. While this holds true only for the southeastern part of the district, it must be remarked that in the northwestern part, in Dry Creek and Pine Flat districts, there is in many cases an undoubted relation between the quicksilver occurrence and igneous actions. In the Dry Creek district the only deposit of any ascertained consequence is the Helen, which lies very close to the tuffs of Pine Mountain. There are undoubted signs of igneous rocks in the Pine Flat district on both sides of Big Sulphur Creek some of these igneous dikes run. as far as determined, in a direction which would bring them near the ore deposits of the Eureka mine ; others were found near the Cloverdale mine. For a great number of deposits, these relations are not yet determined. Considering the intimate relation of quicksilver deposits and aqueo-igneous actions and the general geological conditions in this region, it may, however, be expected that, at least, laccolitic relations exist there. "Between the Corona and St. Helena Creek, a distance of four miles in an air line, along the headwaters of Bucksnorter Creek, the belt of serpentine is very wide. Between St. Helena Creek and Bucksnorter Creek the Standard Quicksilver Mining Company has in the last few years spent a considerable sum of money prospecting, but so far without any favorable result. "To the west of the Great Western mine are the headwaters of Dry Creek, a bowl- form basin nearly encircled by the main ridge and by a ridge dividing Dry Creek from the drainage of Putah Creek. Serpentine is very prominent in a great por- tion of the Dry Creek basin, and again barren of any workable deposits of cinnabar, notwithstanding some very prominent, peculiar croppings, standing out boldly in the serpentine. These croppings, especially prominent in the Wall Street and Jewess grounds, consist of a network of white quartz seams, mostly thin amorph quartz, with occasional concretions of botryoidal form ; the ground mass is a light yellow- brown, ochreous mass; this material is locally called 'dry bone,' and so far as yet observed, never indicates a workable ore deposit. The same is found on the Bacon Consolidated and Cinnabar King ground (Pine Mountain), and also in the Double Star mine CPine Flat). (Lawson's silica-carbonate sinter.) "Pine Mountain is a mass of andesitic tuff, most probably with an eruptive core, of small dimensions and very steep sides, and entirely disconnected from the Mount St. Helena and the Mount Cobb groups of eruptives. Its main ridge is not over 25 feet wide, and about 300 feet long; elevation, 3475 feet. The tuff is of a light grayish color, and has spread over a part of the adjacent ravines. No signs of basaltic rock could be found on the ridge. The Helen mine is situated on the eastern slope," near the edge of the tuff, and on the southwestern, western and northwestern slopes are located a series of mines, comprising the Cinnabar King and Bacon group of mines. The northwestern slope is vei-y steep and partly covered by tuff, which covers alter- nate beds of serpentine and rnetamorphosed sandstones. At the contacts wide belts of croppings show, partly in place, partly covering the side hill with large bowlders. These croppings resemble very much those of the Wall Street and Jewess. In the canon continuing below the old road from Middletown to Pine Flat a very well-defined cropping on the contact of serpentine and sandstone is seen. A great amount of work has been done here ; remnants of old shafts and tunnels are found everywhere on the hillsides, but all work is now abandoned. Several pockets of very rich cinnabar ore were found at different points on the surface, but none appear to have been found persistent in depth. "The headwaters of Putah Creek are situated in a basin on the south slope of Mount Cobb. In this basin are a great number of hot springs, of which Anderson Springs are bv far the most prominent. These springs generally contain a great amount of .sulphur, and in several places sulphur deposition and rock decomposition bv .sulphurous fumes are taking place. Here, as in other parts of the district, cinnabar deposition does not occur in or close to those places where hot waters and vapors reach the surface. Thei-e are no cinnabar mines in this basin — only a few prospects, which can scarcely be said to give, up to the present, much promise of turning into mines ; a condition partly due to insuflRcient development. "The mines around Mount St. Helena have a considerable supply of timber m their vicinitv although the .^itna, Oathill, Corona, Mirabel, and Great "^^estern mines have made serious inroads on the supnlv. The Oathill mine is the only one having a saw- mill The other mines must use roimd timbers, or get their timbers from the sawmills in Lake County at the foot of Mount Cobb. In the Pine Flat district, the timber supplv is rather scant. There is one sawmill in the district. Round timbers cost per set including lagging, from $2.50 to $2.75 ; timbers. 7 cents per linear foot; lagging, 3 J cents apiece ; sawed square sets at mill, $2.15 ; lagging, 15 at 7 cents, $1.05 ; cordwood averages from $2.50 to $3 per cord. 32 CALIFORNIA SI' A TK MINING Bl'REAU. "This district connects by several t;("nl loads witli raihoads. 'I'ln' southeastern and central parts, by three roads to Calistosa — one fr(jm Oathill, the toll road from Middlotown, and the toll road from the Great Westei-n mine; distances, from 12 to 20 miles. The northwestern part connects with Calistoga and Healdsburs. and for the most extreme northwestern portion also with Cloverdale ; distances, from 16 to 20 miles." The above priees are as of IW-i. arul they are quoted here because they furnish an interesting com])arison with i)resent fijiiires which are much higher. CLEAR LAKE DISTRICT. The Clear Lake district comprises the mines around the soutliern lialf of Clear Lake, the only important producer of which has been the famous Sulphur Bank mine. This territory has been a region of intense volcanic activity, a considerable part of it having been at one time covered liy lava flows. There are several periods of eruptions, the ejected lavas being of different compositions. =Moimt Konocti is formed by later andesites, which are also found to the northeast of the lower part of Clear Lake ; but in the close neighborhood of Sulphur Bank the eruptives are principally, but not exclusively, basalts. These latter eruptions must have been recent, the basalt overlying the Quaternary Cache Lake beds. To the northeast of the lava flows in this district is a very extensive belt of serpentine ; but the rocks underlying- the lava flows ai-e, north of Putah Creek, prominently sandstones and shales." (See geological map — Plate VI.) The district finds its railroad outlet, via IMiddletown, through Calis- toga, from which Lower Lake is 33 miles distant. Nearby sources of timber are limited, but fair supplies of cordwood are available. SULPHUR CREEK DISTRICT. The Sulphur Creek district lies to the east of the Clear Lake district, on the line between Lake and Colusa counties, and comprising the upper part of Sulphur Creek above Wilbur Spring's. This region has been considerably eroded, and the ridge near the Abbott mine, form- ing the watershed between Cache Creek and Bear Creek, is in places covered with gravel, some of the pebbles being derived from igneous rocks. ""Two nearl\- parallel l)elts of .serpentine run through the district [see map. Plate VII] with a nortliwest trend. The western runs partb' on aV)ove-mentioned divide; the serpentine is very siliceous in character and rather oi)alini\ On its eastern contact with a belt of rathei' soft sandstone lies a zone of crushed ojialine. To the -west of this serpentine, lietween it and the adjoining shales, is a zone of a light gray or yellow material, containing inclusions (varying in size from small pel)l)les to l)owlders of considerable size) of obsidian, chalcedonite. and opalinized serpentine. Tlie matrix of this breccia is a tuff, or better, a tuffoid (a tuff altered by i-egional metamorphism, according to Miigge). The same material is found ni the Elgin mine. "The sui-face of this serpentine has been leached by acidic waters, leaving a peculiar hard, siliceous material of a light bluish-gray color, full of cavities, and occurring in thin slabs. Near the surface the sei-pentine is generally not silicified, but the ledge matter is largely a much crushed opaline i-ock, more frialile and less hard than the opaline in the tuffoid. This serpentine belt is not very long and is surrounded by shales and argillaceous sandstones. To tlie east is a wider and more continuous serpentine belt, at the westein contact of which are located the Wide Awake, Empire, and Manzanita mines. "The shales contain bitumen, sometimes forming heavy oil, and sometimes lighter gaseous hydrocai-bons. The waters percolating Ihi-ough these formations are often charged -witli hydrogen sulphide. Occasionally they form hot springs. A hot sulphur spring at Planck's Hotel was cut off bv the Wide .^wake shaft when the latter was sunk from the 200 to the 300 foot level, at a distance of 1.300 feet from the spring, and a depth of about 300 feet b(>low tlie spring, and neviM- reappeared, cold watei' now issuing from the same spring. This proves that this spring was caused by hot ascending waters, following a gentle sloiie of aboiit 1:100 feet iKuizontal ^Forstner, op. cit. p. 39. "I<'orstner, op. cit. pp. 40-42. I teir/ifiK— Di?jiK ^ r^^ 'iS(T;l*i^iii] V t GEOLOGICAL MAP Ol- NAPA, SONOMA, LAKE, AND VOLO COUNTY QUICKSILVER DISTRICTS. UNNAMED IGNEOUS AR£AS ARE EITHER ANDB3ITE OR ASPERITE. Reprinted front Bulletin No. 17. PLATE VII. Green=:Serpentine. Geological Map of Sulphur Creek District, in Colusa and Lake Counties. Reprinted from Bulletin No. 21. 3&540 p. 33 4^ — 4J»4*< — i y:,^;jlf nj^ ^ f-7' '^{(!i s^;s;s^ 'VJr m PLATE VII. Greeni=Serpentine. Geological Map of Sulphur Creek District, in Colusa and Lake Counties. Reprinted from Bulletin Xo. 27. I 38.540 p. ."33 QUICKSILVER RESOURCES. 33 to 300 feet vortical. The si'eat amount of mineralized waters, tlie siliceous sinters and sulphur deposits formed by extinct solfataric springs, and the still existing hot sulphur springs, indicate strong irruptivo action. As no igneous rocks appear at the surface in the immediate neighborhood, this may have been laccolitic. In the bed of Sulphur Creek a conglomerate is constantly forming, the pebbles in the creek being cemented b.v deposits from the water which is charged with sulphur and sulpho-salts. "The shales and sandstones occur unaltered and in various stages of alteration. A belt of limestone passes through the Manzanita property, course southeast, adjoining to the west a belt of conglomerate, a water formation, similar to that now forming in the bed of Sulphur Creek. About three fourths of a mile fartlier on, in the same direction, but without any surface connection with this limestone, is found a small body of fossiliferous limestone, with fossils of the Cretaceous age (Rhynchonella Whitney i)." Timber is scarce, cordwood (oak) is high^ and the roads are rather heavy for hauling'. The nearest railroad point is Williams, 26 miles to the east. KNOXVILLE DISTRICT. The Kuoxville district is mainly in the northeast corner of Napa County, and includes also the adjacent portions of Lake and Yolo counties. There is a body of basalt closely associated with the two principal mines, the Knoxville (formerly Boston) and the Manhattan. <"The Manhattan is in contact therewith, and the Boston is in close proximity and practically in line with the direction of the main fissure through which the basalt was ejected. This basalt is the only eruptive body coming to the surface in the district, and lies on the contact between the large belt of serpentine which runs in a southeasterly direction from Cache Creek and the unaltered Neocomian to the north- east thereof. This serpentine belt, which reaches into Napa County and is several miles wide, contains, as far as yet ascertained, only sporadic signs of cinnabar ore, and it is very doubtful if any workable deposits will ever he found therein." Timber has to be hauled from Lower Lake, there being none around Knoxville, though supplies of both pine and oak cordwood are obtain- able at fair prices. The nearest railroad point is Rumsey, 15 miles northeastward, over a difficult road as a deep caiion has to be crossed. Generally supplies are hauled from St. Helena or Winters, via Monti- cello, each about 35 miles distant. NEW ALMADEN DISTRICT. This, the most important quicksilver district in the state in point of total output to date, is about 12 miles east of south from San Jose, and includes the Gruadalupe mine, in addition to the New Almaden company's properties. These mines are in a ridge just back of the foothill spurs which form the Avestern boundary of the Santa Clara Valley at this point, this ridge being a continuation of the Gabilan Range from San Benito County to the south. South of Mine Hill, this ridge is cut through by the sharp caiion of Arroyo de Las Animas: and. decreasing gradually in elevation in its northwest trend, it is cut off northwest of the Guadalupe mine by the caiion of Los Capitancillos Creek. Being wholly within Santa Clara County, the further description of the geology- and topography of the New Almaden district is taken up under the county heading (see post). *Forstner, op. cit., p. 4 2. 3—38540 34 CALIFORNIA STATE MINING BUREAU. NEW IDRIA DISTRICT. The New Idria district, second only to New Almaden in point of total production to date, is situated in the Diablo Range in the south- eastern corner of San Benito County, a portion of the county which, previous to 1888, was included in Fresno County. There are in reality two other, but less important, districts in eastern San Benito County ; but as all three are almost entirely witliin the boundaries of this county, their description is detailed under the county heading. SAN LUIS OBISPO DISTRICTS. The Oceanic. Adelaide, Pine ^Mountain, and San Carpojaro districts are all adjacent, and somewhat closely grouped in the northwestern part of San Luis Obispo County. They are located in zones along the ridges and spurs of the Santa Lucia Range, and are separated by more or less barren sections of country. '"In the northwestern part of this territory near Pine Mountain there is a line of cones formed of rliyolite, having a general northwestern direction. Tlie cones, while close together, are not connected at the surface. Near Pine Mountain, among tlie debris of the rliyolite covering tlie slopes of tlie cones, are found bowlders of diorite, indicating prior igneous eruptions. "In the Adelaide and Oceanic districts some scattered exposures of rhyolite are found, wliicli have no apparent relation to eacli otlier : lience nothing can be inferred relative to the dislocations whicli caused these eruptions. The serpentine lies prin- cipally on the west slope of the main ridge, wliere it has caused enormous slides, due to its deterioration by atmosplieric influences. Its principal exposure is at Cypress Mountain, where, at several places, its contact can be seen witli tlie under- lying partl.v altered sandstones. The entire appearance of the serpentine mass tends to the supposition that it is an altered peridotite. In one place on tlie nortliwest slope of the mountain some signs of induration by contact metamorpliism of the adjoining sandstone can be found. Tlie Franciscan series are prominently repre- sented by sandstones, whicli are very irregular in texture, gi-ading from entirely unaltered arl^ose sandstones into completely metamorphosed sandstones, nearly, if not entirely, quartzite, and these various phases are intimately mixed, without any traceable system of gradation." Fxirther data on these districts are given under San Luis Obispo County. The railroad point for the Adelaide district is Paso Robles, from 16 to 20 miles distant to the east. For the Oceanic district, freight is received by steamers to San Simeon, 13 miles distant, while mail goes by stage fi-om San Luis Obispo via Morro and Canihria. For the countr}^ to the south of Cambria and the Oceanic niiiu\ the ship- ping point is the port of Cayucos. The Pine ^Mountain and San Carpojaro districts ship tlirough San Simeon. LOS PRIETOS DISTRICT. Los Prietos district is in the Santa Ynez Mountains. Santa Barbara County, about 8 miles due noiili ol" Santa Barbara. As the district is wholly witliin that county, it is further described under that heading. OTHER DISTRICTS. As the other, scattered districts, are each within a single county, their descriptions are taken up under tlie county lieadings. Some of them are not at present (•ommercially producing. "Forstner, op. cit. p. 14 9. QUICKSILVER RESOURCES. 35 MINES AND PLANTS. Alphabetically by Counties. ALAMEDA COUNTY. There has been no commercial production of quicksilver from this county; but an occurrence described by Lawson^ is worthy of note. "On the west slope of the Berkeley Hills, north of Berkeley, cinna- bar has been found in a silicified rhyolite fault breccia that outcrops as a prominent knob. Assay of samples taken from the outcrop showed that the rock contains 0.5 per cent of ciuicksilver. On the slopes below this, however, loose fragments of much richer ore have been found. No attempt has been made to prospect the deposit." Bibl. : CxL. State Mix. Bur., Report XI, p. 121. U. S. G. S., San Francisco Folio (No. 193). p. 22. CALAVERAS COUNTY. The occurrence of cinnabar has been noted- in the Oro y Plata, or Blue Wing mine, north of ^Murphy, in a Cjuartz vein "in limestone close to tlie contact with the Calaveras schists. * * * Cinnabar, stibnite, and galena are present in the ore, and it is said to contain copper." 'Lawson. A. C, U. S. Geol. Surv. Geol. Atlas, San Francisco Folio (No. 193) p. 22. 1914. ^Turner. H. W.. and Ransome, F. L.. Geologic Atlas of U. S. : U. S. Geol. Surv., Big Trees Folio (No. 51), p. 6, 189S. I I 36 CALIFORNIA STATE MINING BUREAU. COLUSA COUNTY. The difficulties of mining' here due to the hot waters could probably Sulphur Creek district, the general geology of which is described in a preceding section. ^ The Abbott mine, also in this district, is just over the boundary line in Lake County, and so listed under that county. The following table shows the recorded output of quicksilver in Colusa County, from 1875, the earliest available figures. Quicksilver Production of Colusa County. Tear Flasks Value 1875 ... 700 407 466 $58,905 17,908 17 382 1876 -_. 1877 — 1878 .-. 1895... 1896 _.. 1897 ... 1898 — 1 58 43 40 2,054 1,510 1899 Tear Flasks 1900. 1901. 1902. 1903. 275 235 605 510 12,359 10,575 26,100 21,708 1904 1805 1906 1907 1908 1909 1910 1911 1912 1916 1917 *40O 326 Value $16,526 12,231 - - 17 &48 21 .. 11 900 545 5 230 25 2,438 Totals. 4,105 I $202,059 *Flasks of 75 pounds since June, lyOi; of 76J pounds previou.sly. Elgin Mine. New Elgin Quicksilver Mining Company, owner; AY. S. Norman, president, Spokane, Washington, S. H. Smith, superin- tendent, Wilbur Springs. This property, consisting of one claim, a mill site and 160 acres of patented land, is at the head of Sulphur Creek, in Sec. 13, T. 14 N., R. 6 W., about 4 miles northwest from Wil- bur Springs postoffice. Except for small yields in 1908, 1909, and 1916, the property has been idle for many years, until the present reopening. During 1917, from 4 to 6 men were employed on develop- ment work. One important difficulty in Avorking this mine has been the hot sulphur water present. From the 'lower' tunnel, which is 500 feet above the bottom of the canon, a stream of hot salino-sulphur water (see Photo No. 2) flows over 40,000 gallons per 24 hours. Its temperature is 138° P., and the odors of both snl!)lmretted hydrogen and ammonia are noticeable. It is strongly saline and is said to carry about 2000 grains of mineral matter per gallon. Tliere is a consider- able deposit of flour sulphur along the edges of the stream, as shown by the photograph. Higher up near the top of the ridge there is another similar spring, temperature 152'' F.. wliich also has a strong flow. The difficulties of uiiuiug here due to the hot waters could probably be minimized (if not entirely obviated) by driving a drainage adit 'See D. 32. ante. QUICKSILVER RESOURCES. 37 from the creek level, as the present 'lower' tunnel is 500 feet above the retorts, as already noted. It is stated that such is the present inten- tion. The ledge matter is a black to white opaline rock (the black resembling obsidian) in an altered tufP, with cinnabar and an abund- ance of native snlphnr crystals. In fact, so highly impregnated are parts of the formation here with sulphur (resembling the famous Sul- Photo No. 2. Hot salino-sulphur water flowing from tunnel of Elgin mine, at head of Sulphur Creek, Colusa County. phur Bank mine in Lake County), that in the early history of the Elgin attempts were made to produce sulphur commercially by dis- tillation. The mine is equipped with a Fitzgerald retort furnace, and a partly dismantled mill containing a Jfo Dodge crusher, 8 Colorado bumping tables, and one Wilfley table. Concentration was tried dur- 38 CALIFORNIA STATE MINING BUREAU. ing the operations of 1908-1909. I\rati\- of the old dumps are said to show assays of 0.3%-0.4% mercury. liibliography : Cai.. State Min. Bur., Reports VI, Pt. 1, p. 136; XI, p. 182; XII, p. 359; XIII, p. 594; XIY, pp. 182-184, 188, 189, 196; Chapter rep. bien. period, 1913-1914, pp. 10-12, 16, 17, 24; Bull. 27. p. 43. U. S. G. S., :\rin. Res. 1907, Pt. I, p. 679; 1908, Pt. I, p. 685; 1909, Pt. I, p. 552. Mix. Res. W. of Rocky Mts., 1875, p. 14; 1876, p. 20. Empire-Central Groups. Empire Consolidated Quicksilver Alining Company, Mrs. Emma B. Boggess et al., Wilbur Springs, owners. These two groups of claims are in Sec. 28, T. 14 N., R. 5 W., near Wil- bur Springs, and were at one time, some years ago, operated in con- junction with the Abbott mine. It was reported under option in 1917, with a prospect of work being resumed. Bibl. : Cal. State Min. Bur. Reports XI, p. 186 ; XIII. p. 594 ; XIV, p. 189; Chapter rep. bien. period, 1913-1914, p. 17; Bull. 27, p. 43. Manzanita Mine. Cerise Gold Mining Company, OAvner; J. E. Simpson, president, Orland; Chas. L. Austin, superintendent, Wilbur Springs. This mine, for some years past owned as a part of the adjacent hot springs resort property, was taken over early in 1917, by the present owners jointly with the neighboring old Cherry gold mine. A mill was built to treat the gold ore by amalgamation and concentra- tion, to be followed by the addition of equipment for recovery of cinna- bar and its reduction. Shortly after completion this plant was destroyed by fire, September 3, 1917 ; but is reported to have since been rebuilt. At present writing, it is idle on account of litigation. jWater for the mill is pumped 8000 feet from Bear Creek. IMining will be by open-cuts. Power is obtained by two 50-h.p. Diesel-type crude-oil engines for the mill, and a 12-h.p. engine for the pump. A 6'xl6' Hardinge mill, and 4 Senn pan-motion amalgamators were installed. By reason of the Manzanita 's ore carrying an important percentage of gold as well as cinnabar, in its earlier history the mine was worked for its gold content. While gold has been found at other places asso- ciated with mercury in small quantities (usually little more than a trace), the Manzanita mine is the one notable quicksilvei- mine of the world where there has been a sufficient percentage of gold to work the ore at times for that metal alone. The major portion of Colusa County's gold output^ to date has come from IMaiizanita. The first recorded mention of this gold occurrence was by Whitney- in 1865. who tells of being shown specimens of rounded and water-woi-n ninss(>s 'Spp Cal. State Min. Bur.. Roroit XIV, p. ITfi. 1915. -Wliitney, J. D., Goolosy of CaUforiiia : Geol. Surv. of Cal., vol. I. p. 92, 1S65. QUICKSILVER ItESOURCES. 39 of pure riniiahai-, with specks of native gold enclosed in them, and that "considerablt> quantities of this remarkable combination of ore and metal are said to have been washed out from the bed of a creek in the canon at that place." The rocks are metamorphosed beds of the Knox- ville" series, consisting of thin-bedded, highly altered, and contorted, shaly sandstones, a part of them somewhat serpentinized. The waters of the liot springs nearby are highly charged with sulphuretted hydrogen, sodium chloride, and also contain ammonia and borax. The total quicksilver production of the mine approximates 2,000 flasks, the most of which was obtained by means of concentration dur- ing the eight years up to 1912. This plant is described in the section of the present bulletin under metallurgy.* The mine has been idle since, and the workings largely inaccessible. Relative to the geological evidence then visible underground, Forstner^ in 1903 wrote : "In the mine near the shaft a whitish friable material (leached sandstone) carries sensible amounts of cinnabar. The ledge is very winding in both strike and dip ; the accompanying gouge is also very irregxilar. The hanging-wall shale is in places altered to a whitish material very similar to that above mentioned. The ledge material, especially in the lower 150-foot level, is principally chalcedonite. In places conglomerate is found on the foot wall of the ledge, but it is doubtful if the real foot wall has been reached. This deposit shows plainly that it is the result of deposition out of solfataric waters, as well in the ore body as by their action on the adjacent rocks. To the west of the deposit lies a belt of limestone, adjoining at the west to a belt of conglomerate." Bibl. : Cal. State Min. Bur., Reports V., p. 96 ; VI, Pt. I, p. 33 ; VIII, pp. 157, 159; X, pp. 159, 161; XI, p. 184; XII, pp. 100, 359 ; XIII, pp. 126, 594 ; XIV, pp. 189-191 ; Chapter rep. bien. period, 1913-1914, pp. 17-18 ; Bull. 27, pp. 44, 198, 202. Geol. SuRV. OF Cal., Geol., Vol. I, p. 92; U. S. G. S., Mon. XIII, p. 367; Min. Res. 1892, p. 147; 1902, p. 252; 1907, Pt. I, p. 679; 1908, Pt. I, p. 685 ; 1909, Pt. I, p. 552 ; 1911, Pt. I, p. 901. Eng. & Mining Jour., Vol. 96, p. 783. Mm. & Sci. Press, Vol. 115, Oct. 13, 1917, p. 24 adv. Wide Awake Consolidated Group (Buckeye), This mine, orig- inally known as the Buckeye, is owned by G. A. Martin, Shreve Build- ing, San Francisco. It is about a mile from Wilbur Springs, and south of the creek, in Sec. 29, T. 14 N., R. 5 W., 26 miles southwest from Williams. It is on the opposite (east) side of the ridge from the Abbott mine. The property has been idle since 1901, and the shaft (500 feet deep) is now filled with water. This mine first appeared in the producing list in 1875. After hav- ing been closed for a number of years, it was reopened in 1896 and yielded a small output for a time. The ore, carrying cinnabar, was found at and near the contact between serpentine and shale, strike northwest, dip southwest about 60°. It is .stated that this contact 'Becker, G. F.. Gcolsgy of the (luicksilver deposits of the Pacific Slope: U. S. Geol. Surv., Mon. XIII, p. .367, 1888. ^See p. 3.30, iiost. =Forstner, William, Quicksilver Resources of California: Cal. Ftate Min. Bur., Bull. 27, p. 45. 1903. 40 CALIFORNIA STATE MIXING BIREAU. has been traced for about a mile in the company's ground, though the croppings are more prominent near the phmt. It was worked by both tunnels and shaft, the latter being sunk in the shale. The vein mat- ter Avas found up to five feet wide, mostly soft, with the shale hanging- Avall well defined, while the values were slightly disseminated into the serpentine footwall. The reduction equipment includes a 24:-ton Scott fine-ore furnace. Bibl.: Cal. State Min. Bur., Reports XI, p. 187; R. XIII, p. 594 ; XIV, p. 190 ; Chapter rep. bien. period, 1913-1914, p. 18 ; Bull. 27, p. 45. Geol. Surv. op Cal., Geol. Vol. II, p. 124. Min. Res. W. of Rocky Mts., 1875, p. 14; 1876, p. 20. U. S. G. S. Mon. XIII, p. 368 ; Min. Res. 1908, Ft. I, p. 685. Wilbur Hill Mine. Wilbur Springs Company, owner, Wilbur Springs, postoffice. It is on Sulphur Creek between Wilbur Springs and the Manzanita mine, being in Sec. 28, T. 14 N., R. 5 W., 25 miles southwest from Williams. A small output of quicksilver was made in 1916, with a concentrator and retort ; but only development work has been done since. QUICKSILVER RESOURCES. 41 CONTRA COSTA COUNTY. -J Quicksilver was at one time mined on the eastern slope of the north peak of Mt. Diablo, in Sec. 29, T. 1 N., R. 1 E., associated with serpen- tine and black opal. There are sulphur springs, nearby. During the late seventies the Ryne mine is said to have produced as high as 85 flasks per month, for a time. The occurrences are limited in extent, and there has been no work done for a number of years. Bibl: Cal. State Min. Bur., Report VIII, p. 162; Bull. 27, p. 195. U. S. G. S., Mon. XIII, p. 378. DEL NORTE COUNTY. Diamond Creek Cinnabar Co. J. W. Ehrman, I. L. Cole, and J. L. Taggart, Monumental, Calif., owners. This group consists of three unpatented claims located on the headwaters of Diamond Creek, four miles south of the California-Oregon Line and eighteen miles from Monumental, all but three miles being by road. The presence of cinna- bar here is said to have been known to the early placer miners, who resorted to it in the '50 's for their quicksilver suppl}'. The group was relocated in 1916. The ore occurs in quartz between serpentine walls, and makes in rich bunches, with a general N-S trend. The owners have traced the outcrop 400 yards and have an orebody eight feet wide. So far, they have been able to do only a little hand mining near the surface, two of the owners working. During the past summer they installed a three-pipe Johnson-McKay retort, having a capacity of 500 pounds of ore. The charge is retorted for six hours so that the daily capacity is one ton. The first ton of ore treated is rej^orted to have yielded nearly one-half flask of mercury. The average of the ore is stated to carry l%-2% mercury. Bibl. : Cal. State Min. Bur., Reports XI, p. 198 ; XIV, p. 390 ; Chapter rep. bien. period, 1913-1914, p. 20; Bull. 27, p. 195. U. S. G. S., Mon. XIII, p. 366. Min. & Sci. Press, vol. 29, Aug. 15, 1874. 42 CALIFORNIA STATE MINING BUREAU. EL DORADO COUNTY. Bernard Cinnabar Mine (originally called the Amador). Bernard Cinnabar ^Mining Company, ovvnei- : Leon C. Osteyee, secretary, 127 Montgomery Street, San Francisco; John C. Jens, Belmont, lessee. It is on Fanny Creek, in Sec. 4, T. 8 N., K. 10 E., ^I. D. M., 2 miles west of Nashville and about 8 miles from Shingle Springs on the Sacra- mento and Placerville Railroad. There is a good wagon road from Shingle Springs to the mine. The deposit is a bedded vein in slates and quartzitic rocks ;^ and the cinnabar, accompanied by pyrite, occu- pies interstitial spaces. There is a belt of serpentine about 1/4 mile to the west. The mine was first opened up in the 60 's and some quick- silver produced ; then reopened in 1903, when only development work was done. It has been idle since. The mineral zone is stated to show a width of 20'-50' along the surface, and in the open cuts. There is a vertical shaft, 75 feet deep, connecting with the lower adit which is in 117 feet. Near that point some stoping has been done. The pres- ent lessee is preparing to reopen the mine, this coming spring. Bibl.: Cal. State Min. Bur., Reports XII, p. 359; XV, p. 306; Chapter rep. bien. period, 1915-1916, p. 36; Bull. 27, p. 190. U. S. G. S. Mon. XIII, p. 384; Placerville Folio (No. 3), p. 3. Geol. Surv. of Cal., Auriferous Gravels, p. 367. Min. & Scl Press, vol. 31, p. 718, 1875. 'Beckftr, G. F., Geolog-\- of the riuicksilver deposits of the Pacific Slope : U. S. G. S., Mon. XIII, p. 384, 1888. QUICKSILVER RESOURCES. 43 V FRESNO COUNTY. In the various earlier reports and papers, it is to be noted that the mines of the New Idria district were described as being in Fresno County : but in 1888. the county boundary was changed, so that New Idria is now in San Benito County. The quicksilver localities within the present boundaries of Fresno County are along its western edge, in the eastern foothills of the Diablo Range. Recorded quicksilver production of Fresno County (for New Idria district, see under San Benito County), is shown in the following tabu- lation. As the figures of earlier years were small and scattering, they were included under the designation of "Various Mines" in published tables. Quicksilver Production of Fresno County. Tear 1 1 Flasks Value Tear Flasks Value 1912 — 1913 336 375 148 $14,125 15,086 7,259 1916- 1917 *10 * *$875 1914 __. 1915 — Totals 869 $37,345 ♦Figures for 1916 and 1917 combined to conceal output of a single producer. Archer Mine. Joseph Byles & Sons, Coalinga, owners; Ben J. Byles, manager. This group of six claims located in 1904. is in Sees. 2 and 3. T. 18 S., R 13 E., M. D. M., 28 miles northwest of Coalinga, and near the ^Mexican mine. Up to 1916, a small amount of quick- silver was produced, using a retort consisting of six 9-incli pipes. A Johnson-]\IcKay retort has since been built; and selected ore is treated : but it is stated that there is considerable low-grade material in sight. The ore carries cinnabar and pyrite. the country rocks being serpentine and slate. There are five tunnels ranging up to 200 feet in length, and several open cuts. Bibl. : Cal. State Min. Bur., Report XIV. p. 462 ; Chapter rep. bien. period, 1913-1914, p. 36. Mexican Mine. Antonio Urrutia et al., Panoche, owners. This group of three claims in Sec. 22, T. 18 S., R. 13 E.. northwest of Coalinga. and nine miles southeast of New Idria. was originally located in the sixties. Development work consists of several adits and some surface cuts. The vein is in sandstone of the Franciscan series close to its contact ^vith the overlying Panoche formation, and carries cinnabar associated with silica and oxides of iron, the oxidation pro- 44 CALIFORNIA STATK MINING BUREAU. duct of iron .sulphides. Only assessiuciit work has been done of recent years. Bibl. : Cal. State Min. Bur., Report XIV, p. 462 ; Chapter rep. bien. period, 1913-1914, p. 36; Bull. 27, pp. 119, 120. U. S. G. S., Bull. 603. p. 207. New Mercy Mining- and Development Co. ( formerly [Mercey Min- ing- & Development Co.; also Pacific Quicksilver Co.; includes prop- erties and claims formerly known under names of Providential. Aram- bide and Aurecoechea, ]Mercy, Croxon). A. R. Warthen et al.. owners; J. Norrish, manager, Los Bafios, c/o Mercey Hot Springs stage. This group includes eighteen claims and five mill sites on a branch of Little Photo No. 3. Furnace at New Mercy (Pacific) Quicksilver Mine, Fresno County. Panoche Creek, in Sees. 32 and 33, T. 13 S., R. 10 E.. and Sec. 5, T. 14 S., R. 10 E., 25 miles southwest of South Dos Palos on the South- ern Paeifie Railroad, and 29.1 miles fi-om Los Baiios. Elevation 1600 to 2000 feet (U. S. G. S). Tlie first work is said to have been done here about 1860. The Pacific Quicksilver Company operated the property from 1911 to the end of 1914; since which time it has been idle until late in 1917. The country rock is principally a metamorphic sandstone, and the ore occurs in a series of leached zones witli quartz and ochre. Relatively little cinnabar can be seen except i>n panning, QUICKSILVER RESOURCES. 45 ■when the odireous material is observed to yield a good percentage of ■concentrate. There is a little pyrite with the cinnabar. Formerly the principal work was done on the Providential and Gabilan claims, but in September, 1914, the ore supply was being drawn from tlie Arambide from a new shoot uncovered in the preced- ing spring. Here the values occur in a series of small veins and stringers over a width of 24 feet, striking east of south and dipping about 60^' E. On this claim there is a 100-foot shaft and 400 feet of adits; and on the Aurecoechea 3000 feet of work, including a 150-foot shaft. Photo No. 4. Drawing off burned ore, New Mercy (Pacific) Quicksilver Mine, Fresno County. The reduction equipment includes a 24-ton Scott fine-ore furnace (see Photo No. 3), and two 'D' retorts with a capacity of 300 pounds each. They are oil fired. In 1914, crude oil cost 88 cents to $1.10 per barrel delivered at South Dos Palos, plus $1.17 per barrel freight to the mine. The furnace is 4 tiles long, 50 tiles high, with a 4-inch spac- ing. The condensers consist of 14 brick chambers and 6 Knox- Osborne cast-iron chambers, the latter being connected in between No. 2 and No. 3 of the brick series (see Photo No. 58, post). From the mine the ore was hauled about ] mile in a bottom-dump wagon onto an ore bin, from whii-li it was trammed to the jaw crusher (run bv a 46 CALIFORNIA STATE MINING BUREAU. small steam enofine), then trammed to tlie furnace. The burned ore was drawn off into a side-tipping steel ear (see Photo No. 4). and trannned to the dump. Bibl.: r.\i.. State :\Iin. Bur., Report XIV, pp. 462-464; Chapter rep. bicn. period, 1913-1914. pp. 36-48; Bull. No. 27, pp. 119, 121. U. S. G. S., :\ron. XIII. p. 380; Min. Res., 1912, Pt. I, p. 939 ; 1913, Pt. I, p. 204 ; P>ull. 603, p. 207. GLENN COUNTY. Cinnabar has been reported on the J. ]M. N\ye ranch, southwest of Fruto, and on the Turner ranch Avest of Elk Creek postoifiee. Not developed. Bibl.: Cal. State Min. Bur., Report XII, p. 360; XIV. p. 199; Chapter rep. bien. period, 1913-1914, p. 27. HUMBOLDT COUNTY. E. F. Wilder, Orleans, has locations made about 1915, in IMill Creek district, near Orleans Bar on a vein carrying cinnabar; but so far onl\' a small amount of development work lias l)een done. INYO COUNTY. Small amounts of both cinnabar and metacinnabarite have been noted in the Cerro Gordo mine,^ near Keeler, but apparently' not in commercial quantities. A vein in limestone containing cinnabar and metacinnabarite has been noted- on one of the claims of the Chloride Cliff mine in the Funeral Mountains west of Rhyolite, Nevada. An 80-foi)t tunnel lia.s been driven on the vein, exposing some fair ore ; but no quicksilver has been produced. Owned by J. I. Crow(^ll. Donald Findley, and Cha.s. Parsons, of Rhyolite, Nev. Bibl. : Cal. State Min. Bur., Bull. 67, pp. 32, 34 ; Mines & Min. Res. of Alpine, Inyo & Mono counties, p. 117 (also Report XV, p. 121, in press). U. S. G. S., Bull. 61. 'Melville, W. H. & Lindfircn, W., Contributions to the mineralogy of the Pacific Coast: U. S. Geol. Surv. Bull. 61, 1S90. -Waring, C. A., & HuKnenin, P^mile, Mines & Min. Res. of Tnvo Coiinl\- : Cal. State Min. Bur., Biennial report 1915-1916, p. 117, 1917. Also in Report XV, p. 121, 1918. QUICKSILVER RESOURCES. 47 KERN COUNTY. Quicksilver production in Kcin County began in 1916, following the discovery of cinnabar in workable quantities close to the famous Tehachapi Loop of the Southern Pacific railroad, near the town of the same name. Slightly over 300 flasks have been produced to the end of 1!)17. with two mines in operation, the major portion of the output coming from the Cnddeback. Cuddeback Cinnabar Mine. J. P. Cuddeback, Tehachapi, owner; Cuddebaek Cinnabar Company, lessee, Tehachapi; A. J. Blackley, president. The mine is on land owned under an agricultural patent, being in Sec. 27, T. 31 S., R. 32 E.. ]M. D. M.. 3 mi. from Woodford Photo No. 5. Cuddeback Cinnabar Mine, near Tehachapi, Kern County. (Keene, post office) station on the Southern Pacific, and a half mile by road from the main county highway at the Loop. The country rock for several miles around is granite, and the white rhyolite dike traversing the granite witli a nearly E.-W. strike is plainly visible from the passing trams (see Photo No. 5. — the dike crosses the hill from left to right, just above the dumps), though the outcrop is not a bold one. The dip is N., about 45° ; and the width is at least 60 feet where most of the work lias been done. Tlio dike rock is a somewhat poi'ous. finely gi'ainilar. p()ri)hyi'i1 ic rhyolite, showing quartz and ortho- 48 CALIFORNIA STATE MINING BUREAU. clase phenucrysts under the niieruseupe (see Photo No. 6). Cinnabar crystals are disseminated through the ground-mass, in some places to such an extent as to give the whole rock a pink color, macroscopically. Portions of the rock whicli are white, and to the unaided eye appar- ently barren, show finely disseminated cinnabar under the glass. From this, the writer presumes that a considerable portion of the dike would pay to mine and reduce with a lar^o furnace equipment which could economically treat a large tonnage of low-grade ore. Of course, this can be definitely determined only by a careful sampling across the full width of the dike. Photo No. 6. Micro-photograph of porphyritic rhyolite carrying cinnabar, from Cuddeback Mine. The black specks are cinnabar. > 60 diam. magnification. Photo by S. A. Tibbetts. The richer accumulations of ore appear to be associated witli cer- tain cross-fi.ssures in the dike whicli are marked by the presence of brown clay seams. The mineralizing solutions apparently came up through these fissures, spread out into and impregnated the somewhat porous rhyolite, similarly to the impregnated sandstone ores as at Oat Hill, Napa County. So far as observed, the rhyolite is but little altered, and the adjacent granite is fairly fresh. At this point, tlie mineralized portion of the dike is \ mile long; and though the dike itself is traceal)I(' beyond, it seems not to show enough cinnabar to be workable beyond. The development work eousists of several short adits, crosscuts, drifl.s, small stopes, and open cuts; and when visited in September. 101 7. a depth of a])out 50 feet below tlie outcrop had been altainci! in a di'ift and sti^pc aroniid th(^ point of the liill to t1ie QUICKSILVER RESOURCES. 49 right of the photograph (No. 5). Reduction equipment consists of a 12-pipe Johnson-]\rcKay retort, oil-fired. Thoi-e were also a 6 h. p. ga.ter rep. l)ieii. period. 1913-1914. p. 103; Bull. No. 27. p. 122. Francis Claims (see Kings Quicksilver Mining Company). Kings Quicksilver Mining Company, Ltd. Win. Gray, president; W. P. Darsh, secretary; office, 520 King street, London. Ontario. Can- ada. A. A. Lewis, superintendent, Parkfield. This |)i'operty includes the Segregation and Summit claims owned by C. F. Francis of Park- field, under bond, besides a number of claims located by members of the company on adjoining ground. The group is principally in Sec. 20, T. 23 S., R. 16 E., 14 miles by road east of l^irkfield and 40 miles north of east from San Miguel on the Coast Division of the Southern Pacific Railroad. Elevation 3100 feet (bar.) at the lower tunnel. \ QUICKSILVER RESOURCES. 51 The country rocks are serpentine, shale and metamorphic sandstone. The ore values occur in a crushed zone, in part as stockworks, earryinji' cinnabar and native mercury with some calcite. In the upper level this zone shows about 35 feet wide, with strike southeast and dip 45° to 50° SW., and in September, lPl-4, had been drifted on for 70 feet. The upper adit was in 700 feet (part crosscut and part drift), with two raises to the surface and one winze of 85 feet to the lower adit. The latter has 850 feet of work and reaches a depth of 200 feet below the outcrop. Hand drills and augers were used. The mine was originally worked about 1902, and again in 1905 and 1910, during which operations it is credited with a total output valued at over .$13,000. The reduction equipment consisted of a series of pipe Photo No. 7. Ten-ton Scott fine-ore furnace and condensers, Kings Quicksilver Mining Company, Ltd., Kings County. retorts. The present company in 1914 completed a 10-ton Scott fine- ore furnace (see Photo No. 7). with brick condensers, which was oper- ated with .some interruptions up to the close of 1916. The bricks were burned in a field kiln at the mine. A concentrating mill was also built, and operated for .some months. This is described in the section under Concentration.^ The mill and the rock breaker were driven bv a 25 h. p. crude-oil engine; and the furnace blower by a 4 h. p. distillate engine. During the summer of 1917. the Scott furnace was utilized by the King ^Magnesite Co.. to calcine magnesite from their deposit 'See p. 33S, post. 52 CALIFORNIA STATE MINING BUREAU. iiearhy. Tlic pioixTty is at present (February, 1918) under option to the Patri(juiii IJi-ollicrs of Paj'kfi(>l(l. who jn-opose to reopen it the com- ing* spring. Bibl.: Cal. State IMin. Bur., Report XIV, p. 529-530; Chapter rep. bien. period. ] 91:3-1914, pp. 103-101; Bull. No. 27, p. 122. U. S. G. S.. Min. Res. 1902, p. 253; 1912, Ft. I, p. 939; 1913, Ft. I, p. 201. LAKE COUNTY. Prospecting and exploitation of quicksilver deposits in Lake County began in the early sixties, and the Abbott mine was a producer as early as 1870. There was no notable production, however, until 1873. As will be noted by reference to the table of production, quicksilver min- ing was most active in this county from 1875 to 1882. There was a revival between the years 1891 and 1896 ; but beginning with 1905 there was a rapid decline, until it reached an almost insignificant figure just preceding the present improved market. There were but two pro- ducers in 1913 — the Helen and the Wall Street, both of them being near Middletown. It may be noted here that in some of the early reports and press notices the Knoxville mines (Manhattan, Lake, Red- i ington, Boston) were erroneously referred to as being located in Lake County. They are in Napa County. There are four recognized quicksilver districts either wholly or in part located in Lake County: (1) Mayacmas, the largest, is in south- western Lake and extends over into northeastern Sonoma and north- western Napa; (2) Clear LaJie district is around the eastern, southern, and southwestern sides of Clear Lake; (3) Knoxville district is at the junction of Lake, Yolo, and Napa, being principally in the last named; (4) Sulphur Creek district is almost wholly in Colusa but includes the Abbott mine which is on the eastern edg:e of Lake County. The gen- eral geology of these districts is described in preceding paragraphs at the l)eginning of this chapter.^ I The recorded quicksilver yield of Lake County is showai in the fol- lowing tabulation. The actual production is known to ])e in excess of these figures, due the production of some of the smaller mines previous to 1894 being included with mines of other counties, unapportioned, under the designation, "various mines." For many years quicksilver was the premier mineral in output for the county; but between 1903 and 1914, it was surpassed by mineral water. 'See pp. 30-33, ante. QUICKSILVER RESOURCES. Quicksilver Production of Lake County. .5^3 Year Flasks A'alue Tear Flasks Value 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 188;^ 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1 8, 14, 18, 14, 15, 17 17 10, 6, 4, 4. 3, 4. 6. 4. 4, 4, 11. 9 12, 12. 6, 880 695 821 199 100 428 582 148 393 193 481 182 765 498 307 636 713 232 975 140 731 471 8.56 307 $70,790 178.280 743,287 624.756 675,130 474,681 309,303 531,588 518,833 287,748 186,329 127,551 146.524 124,179 182,509 282,030 212,085 222,180 225,119 453„509 357,614 382,954 465,074 232,484 1897. 1898. 1899. 190). 1901 . 1902 . 1903. 1904. 1905 . 1906. 1907. 1908. 1909. 1910. 1911 . 1912. 1913. 1914. 1915 . 1916. 1917. 3,585 1,729 2,954 3,165 4,395 3,611 2,595 *2,854 1.462 1,066 802 1,800 1,075 1,048 899 209 395 331 492 1,399 1,067 $134,.546 64,746 128,179 127,345 211,324 161,568 106.397 109,719 51,937 38,909 30,604 54,951 56,277 47,422 41,363 8,786 15,891 16,2.36 41,660 130,806 107,071 Totals 251,166 $9,700,274 ♦Flasks of 75 pounds since June, 1901, instead of 73j pounds as previously. Abbott Mine. E. A. Boggess et al., "Wilbur Springs, owners. The Abbott group is on the eastern border of Lake Count}', in Sec. 32, T 14 X., R. 5 W., about two miles in an air line and three by the road from Wilbur Springs post office. Colusa County. It includes also, the old Di.sturnell. This group was formerly operated by the Empire Consolidated Quicksilver ]\Iining Campany; but the property has been in litigation at various times, and apparently is still not fully settled. The mine was discovered in 1862 and began production in 1870, con- tinuing to 1879 ; then idle from 1879 to 1889 ; and again operated, for a period of sixteen years, till closed down in 1906 ; since which it has been idle except for a short period, February 1916, to ]Mar. 17, 1917. The mine is credited with a total production to date, of 30,8-15 flasks. During 1916, the ore treated was obtained from an old glory hole and by working over some of the old dumps. The underground workings are quite extensive, the greatest depth, however, being only 350 feet below the collar of the 'Bogge.ss' shaft (see Plate VIII). There have been no important developments underground, since Forstner's^ report. "This mine lies on the soutliwestern contact of a serpentine belt, strike northwest, with a shale country rock, occasionally sandstone. The serpentine varies in width from a few hundred feet to a quarter of a mile, and is about 2 J miles long. To the northeast is a belt of sandstone, rather narrow in the southern portion, but widening rapidly going northward. * * * The serpentine is interstratified with beds of shales and sandstone * * * ; the same alternations are found underground. * * * The map of the mine workings indicates that they follow generally the line of con- tact of the tuffoid. with the shales lying west thereof. * * * The shales west of the serpentine contain some hydrocarbons. In places petroleum is found ; in others, gases of light inflammalile hydrocarbons emanate from the rock or bubble up through the water * * * The cinnabar ore forms in these bands of serpentine, more especially in close proximity to the tuffoid ; exceptionally the ore is found in the shale. The gangue is generally strongly crushed opaline. Metacinnabarite occurs occa- sionally, * « * The cinnal)ar is disseminated through the crushed opaline, partly as face metal, but also in seams and pockets. The ore zones contain a great amount of iron sulphides, * * • Very little gouge is found between the ore bodies and the walls. The groimd in the ore zones and in the shales is often swelling, but the tuffoid stands very well." 'Forstner, William. The quicksilver resources of California : Cal. State Min Bur., Bull. 27, pp. 46-48, 1903. 54 CALIFORNIA STATE MINING BUREAU. H < a. QUICKSILVER RESOURCES. 55 The rednction equipment consists of a -t8-ton Scott furnace, with an ore drier located between the crusher and furnace. Present reports (IMarch. 1918) are that the i)roperty is being refinanced, and will be reopened. Ribl.: Cal. State Min. Bur., Reports IV, p. 336 (tc-.ble) ; XI, p. 239; XII, p. 360; XIII, p. 595; XIV, p. 229; Chapter rep. bien. period, 1913-1914, p. 57 ; Bull. 27, pp. 46-48, 227 ; Reg. of Mines. Lake County, p. 3. U. S. G. S., Mon. XIII, p. 368 ; Min. Res. 1902. Geol. Surv. of Cal., Geology, vol. II, p. 124. Min. Res. W. op Rocky Mts., 1876, p. 19. Anderson Prospects, owned by members of the Anderson family of Anderson Springs. They are in Sees. 25 and 35, T. 11 N., R. 8 W., near ]\Iiddletown. They have not been previously developed but are now (March, 1918) being opened up by R. B. Crowell, lessee, under the name of Big Chief. Bibl. : Cal. State Min. Bur., Bull. 27, p. 48 : Rep. XIV, p. 230 ; Chapter rep. bien. period, 1913-1914, p. 58. Bacon. Abandoned. Reg. of Mines, Lake County, p. 3 : Rep. IV, p. 336 (table); XIV, p. 230; Chapter rep. bien. period, 1913-1914, p. 58. Baker Mine. Baker Quicksilver Company, owner; A. R. Short, president, 1100 Delmas Ave., San Jose. The group consists of two patented claims, Baker and Trade, and 65 acres of agricultural pat- ented land adjoining on the east side of Soda Creek, in Sec, 16, T. 12 N., R. 6 W., 6 miles southeast of Lower Lake. The county road passes near the mine. The Baker was first worked at least as early as 1870, and has been operated at various times in a small way. Present oper- ations were begun in 1916 when the dumps were worked over with a screening and concentrating plant and some surface ore taken out in an open cut. The earlier underground workings are caved. In 1917, a two-compartment incline shaft has been sunk 100 feet, and drifting is now being .started. The topography in this vicinity is characterized by a series of rolling ridges and small valleys with longitudinal axes approximately north and south. There is a sparse growth of oak and pine timber. • There are two ore zones, with strike varying from N. 20°, W., to N. 60° W.. and dip of 45° NE. The ore bodies showing widths of 10' to 20', are stated to be in altered shale at a contact with serpentine, both being overlain by sandstone. No. 1, or the West vein, is trace- able on the .surface for about 4000 feet ; and No. 2, or the East vein, is 75 feet distant, l)eing traceable from near the southeast end of the 56 CALIFORNIA STATE MINING BUREAU. Baker claim to the northwest end of the group. The cinnabar occurs disseminated in a zone of crushed and altered material, with occasional high-grade pockets, and associated with iron sulphide and metacinna- barite. From assays reported, the average of the material as a whole appears low grade. Most of the development haa been done on No. 1 vein. Mining equipment consists of gasoline hoist, pump and blower. Surface ore is being taken from an open-cut, sluiced through a revolv- ing screen, and the fines passed over concentrating tables. Water is piped 2,000 feet from Soda Creek, with a raise of 140 feet. The con- centrates are reduced in a 7-pipe retort. At present 5 men are employed. Bibl.: Cal. State Min. Bur., Reports XI, p. 67; XII, p. 360; XIII, p. 595 ; XIV, p. 230 ; Chapter rep. bien. period, 1913-1914, 58 ; Bull. 27, p. 49 ; Reg. of Mines of Lake Co., p. 3. U. S. G. S., Mon. XIII, p. 368. Geol. Surv. of Cal., Geology,* vol. II. p. 125. Big Injun Mine (includes Big In.iun and Digger Injun claims). Peake, Miller, et al. (Union Construction Co.), owners, 604 Mission St., San Francisco ; R. B. Crowell, Middletown, buying under lease and option. This group, consisting of the Big Injun and 8 other claims, is in the S. ^ of Sec. 35, T. 11 N., R. 8 W., M. D. M., 7 miles northwest from Middletown and a mile south of Castle Hot Springs by sled road. There is an automobile road as far as Castle Springs. The outcrop was discovered about 1873, b}^ 'lujun Jeif'. It had been worked occa- sionally in a small way, but was idle for some years preceding its being reopened by the present lessee in 1916. The mine is apparently on a contact of serpentine and sandstone, but the formations are con- siderably broken up at this point. There are two 'veins' or ore zones, the principal development having been done on the eastern one. The strike is NW., and dip SW. The width varies up to 30 feet, with ore shoots showing l'-4' wide. The hanging-wall is somewhat heavy to hold, especially in winter. The ore is characterized by the presence of considerable native mercury with cinnabar ; and the gangue minerals are quartz and dolomite. There are 3 main crosscut adits, the lowest being in 550', reaching a depth of 150' below the outcrop. At 350' in on this crosscut there is a liot sulphur spring. The ore is treated in two 'D' retorts, 700 pounds per charge, 3 charges per 24 hours. A water-spray was at one time tried in the condenser, but diseontiiincd because of flouring the (|iiicksilver. The condensing system on each retort consists of 20 feet of 6-inch thick-wall cast-iron pipe, and a verti- cal wood-stave tank 3' diam. x 8' high, (see I'hoto No. 8) with a con- I 4 QUICKSILVKK RKSOTTRCES. 57 Crete floor. There is also a shakiiiii' screen and a Standard concentrat- ing- table, which are used to dress low-grade ore, during the winter months. A revolving screen will he added. The fines from the screen go to the table. The ore retorted during 10 months up to September, 1917, yielded an average of 2% mercury. Wood consumed was 20 cords per month, at a cost of: $2 for cutting, 50^ stumpage, and $3 hauling, per cord. An average of 12 men were employed, 6 of whom were underground @ $3 per day. Bibl. : Cal. State Mm. Bur., Report XIV, p. 230 ; Bull. 27, p. 50 ; Chapter rep. bien. period, 1913-1914, p. 58. Photo No. 8. Retorts and condensers at the Big Injun Mine, near Middletown, Lake County. The Bullion Mine is 4 miles southwest of Middletown, between the Mirabel and Great Western, Ben H. Otto, J. W. Wrieden, and Chas. Elliott, owners, ]\Iiddletown. It was formerly worked by the Mirabel Company, and had been abandoned for several years, but was relocated in August, 1913. In tlie spring of 1917, a few flasks of quick- silver were produced l)y concentrating old dump material with hand rockers. The concentrates were retorted. Some development work was also carried on. Bibl.: Cal. State ]\Iin. Bur., Reports XII, p. 360; XIII, p. 595; XIV, p. 230; Chapter rep. bien. period, 1913-1914, p. 58; Bull. 27, pp. no. 01. 58 CALIFOHMA STATK MIMXG BrKEAT. Chicago Mine (oi'i^inall>' known as the Pittsburgh; also Ural). This property is owned by the Chicago Quicksilver IMining Company, 522 Bank of San Jose Building, San Jose, Cal. Tt is in Sec. 1, T. 10 N., R. 8 W., about ^ mile west of the Wall Street mine, near IMiddletown. It has l)e(Mi idle for some time. The last operations here were in 1911 on the construction of a tine-ore furnace of 15 tons capacity, with con- crete walls. The furnace was not finished, and consequently never operated. It would be interesting to note the behavior of the concrete when heated. It looks to be an experiment with rather a doubtful outcome. Bibl: Cal. State Mm. Bur., Reports XIII, p. 595; XIV, p. 230; Chapter rep. bien. period, 1913-1914, p. 58 ; Bull. 27, p. 51 ; Reg. of :\rines. Lake County, p. 8 ; U. S. G. S. Min. Res. of U. S. 1909, Part I, p. 552 ; 1910, Part I, p. 697 ; 1911, Part I, p. 901 ; 1912, Part I, p. 940. Great Western Mine. H. M. Newhall & Co., ow^ners, Newhall Build- ing, San Francisco. It is 4 miles southwest of Middletown, and two miles northwest of the ^Mirabel mine, at an elevation of 1860 feet. This mine has, so far, had the longest continuous record as a producer of any quicksilver mine in Lake County. It was opened up in 1873, and was a constant producer up to 1909, being credited with a total yield, to date, of 98,316 t^asks. A few flasks were recovered in 1912 in cleaning-up around the old furnaces; and, again, in 1916, by a lessee with one Standard table, wa.shing and concentrating material from some of the dumps. The former operating company has been dis- incorporated, the furnaces torn down, and the mine abandoned as worked out. In 1916 and 19i7, some chromite was shipped from lenses opened up by lessees, in a body of serpentine on the property. As might be expected from its output record, the Great Western mine has extensive^ underground workings, and to a depth of 750 feet. The mine and its geology are described at some length in the reports noted under Bibliography. The general strike of the ore body was north- west, with a (lip of about 70° SW. The footwall is a very hard sedi- mentai'y rock altci'cd i)y silicifieation,'- locally calhMl 'greenstone'; and the hanging wall, at least at the surface is serpentine. The ledge matter Avas formed by a series of thin ])eds of chert, having their bedding planes parallel to the strike of the ledge and interstratified with day seams. This cli(M-t was locally called '(|uartzite. ' The dip of the ser- pentine being (latter than that of tlie ledge matter, the intervening space was filled with a black 'alia.' The cinnabar occurred in an irreg- ular niannei-. LicneralK- in seams, and as face metal in the fractures of I 'Whitnev. .7. I)., GooloRV of Californlii : Geol. Surv. of Cal.. vol. T. p. !tO, 1865. 'Fnv:ini'r. Willi:ini, Tlic Mnirksilvi r ri'snurcps of California : Cal. .^tate Min. Bur., null. L'T, p. .">!, iiin.1. QUICKSILVER RESOURCES. 59 the chert, bnt in tlie richer spots disseminated through the chert itself, associated with pyrite. The main working shaft was sunk vertically in the footwall. The property was equipped with a 40-ton Litchfield furnace. Bilil.: C.VL. State Min. Bur., Reports X. p. 270; XI, p. 64; XII, p. 861 ; XIII, p. 595 ; XIV, p. 231 ; Chapter rep. bien. period, 1913-1914, p. 59; Bull. 27. pp. 52-55; Reg. of Mines, Lake County, p. 3. U. S. G. S., Mon. XIII, pp. 358-362, 470; Min. Res. of U. S., 1883. 1884. 1892, 1902, 1906, 1907, Part I ; 1908, Part I; 1909. Part I; 1912. Part I. Min. Res. W. op Rocky Mtxs.. 1874. 1875. 1876. The old Hays mine in the E. ^ of NE. i of Sec. 18, T. 10 N., R. 7 W. ( .'), ]\I. D. ]M., near Middletown, has been idle for many years. Some fair looking- pieces of ore are reported to have been picked up on the dump. ]\Ir. Knapp, owner, Oakland; Geo. Lewis, agent, ]\Iiddletowu. Helen Mine (originally called 'Dead Broke'^; one time known as the American. Andrew Rocca, owaier, ]\Iiddletown ; Andrew Rocca, Jr., superintendent and manager. This mine is in Sec. 1. T. 10 N., R. 8 W.. :\I. D. :\I.. 6 miles west of :\Iiddletown, at an elevation of 2675 feet (barometric reading at bottom of furnace). It consists of two claims, the Helen and the Austin, which were patented in 1874 by Pushbecker. later sold to the American company and to the present owner in 1900. The property includes between 600 and 700 acres (partly timbered) besides the mineral claims' area. The timber, some- what scattered for the most part, consists of pine, oak, madrone, and 'fir' (Douglas spruce. Pseudotsuga taxifolia). The mine is at the head of the north branch of Dry Creek. The first recorded production of the Helen mine was 128 flasks in 1873, and it is credited wdth a total yield of something over 6.000 flasks to date. The mineralized ledge is up to 100 feet wide, with an average of 30 feet. It is at the contact of serpentine with sandstone and slate, and has a black gouge on the hanging-wall. The vein outcrop is prominent, and strikes X. 40^ W.. dipping 30° to 40° S. There are three main levels at present operated, being by tunnels, one of which is in 2.000 feet giving a depth of 316 feet below the outcrop. The ore shoots are from 70' to 100' long, and 5'-10' wide. The ledge has been proven underground by drifting, for 1000 feet in length. The ore is cinna- bar, intermixed with pyrite, and occurs in seams, sometimes an inch or two thick, of solid cinnabar. These seams are approximately parallel to the ledge, and are crossed at high angles by other and rather minute ore seams. The serpentine is in i)ai't silicified and carries lenses of 'Whitney, J. D., Geology of California: Geol. Suiv. of Cal., vol. I, p. 89, 1865. 60 CALIFORNIA STATE MINING BUREAU. hard. liii('-,i;i';iiii('(l black ' jasperoid. ' On the outcroi), sonic ore has been stoped out to the surface. Mining' is conducted by square-set stoping, beinj; 75%, by overhand and 25% by underhand sloping. The ore is trammed, horse-drawn, from mine to furnace in trains carrying 3 tons per trip. Both the mine and the furnace have been steadily in operation foi* some years past, at present having 25 men at work — 12 underground, 6 on top, and 6 on the furnace. The furnace is a 50-ton Scott (see Photo No. 0), and has special condenser arrangements designed by Mr. Photo No. 9. Fifty-ton Scott furnace at the Helen Mine, near Middletown, Lake County. Old dumps of the Wall Street Mine in the distance. Rocca, ill whicli the draft is (juntrolled by dampers. It is said to work satisfactorily. The owner states that the ore being reduced averages 0.6% quicksilver, and that he can handle at a profit ore carrying down to 0.25% of the metal. Soot from the condensers, and occasional small lots of rich ore are treated in a 'D' retort of 750 pounds capacity. A small gasoline engine, run intermittently, furnishes power for the rock breaker. The furnace consumes 1^ cords of firewood per 24 hours. The mine equipment includes a 25 h. p., type NB, Fairbanks-]\Iorse oil engine, and a 25 h. p. or "100 cu. ft. of free air pi>r minute." Inger- soll-Rand class E R I compres.sor. This oil engine is stated to operate at a cost of 20^'- ])er horsepower-day. Operating costs are given at $4.10 per ton of ore, distributed as follows: development .$2.20; mining QUICKSILVER RESOURCES. Gl $1.15; treatment 60^; g'eneral 15f. An 80% recovery is claimed. As the upper parts of the mine are ditificult to work on account of water in the wet season, only tlie lower levels are worked during the winter months. Bibl. : Cal. State :\riN. Bur., Reports XII, p. 362; XIV, pp. 231- 233 ; Chapter rep. bien. period, 1913-1914, pp. 59-61 ; Bull. 27, pp. 55-57 ; Reg. of Mines, Lake County, p. 3. U. S. G. S., Mon. XIII, p. 375; Min. Res. 1902; 1907, Part I; 1908, Part I; 1909, Part I ; 1911, Part I, p. 901 ; 1912, Part I, pp. 9-40-942 ; 1915, Part I. p. 269. Min. Res. W. of Rocky Mtns., 1874, p. 30. Geoi.. Surv. of Cal., Geol. vol. I, p. 89. Jewess Prospect (also known as Franklin). It is near the Helen and Wall Street mines, but so far as known has never produced any quicksilver. Idle for several years. Bibl. : Cal. State Min. Bur., Report XIV, p. 233 ; Bull. 27, p. 57 ; Chapter rep. bien. period. 1913—1914. p. 61. Lucitta Mine (also known locally as the Uncle Sam). ^Mount Sam Mining Co., owner; Theo. A. Bell, president, 701 Crocker Building, San Francisco. This group of four claims is located on the south slope of :\Iount Konocti (or Uncle Sam), in Sees. 20 and 21, T. 13 X.. R. 8 W., ]M. D. M., about 7 miles southeast of Kelseyville. The mine has not been worked recently nor has it reported any production for several years past. The formation, here, is mainly igneous,^ boulders of andesites being prominent, the intervening material being a decom- posed tuff bleached by solfataric action. White beds of leached meta- morphic shales are found in these igneous masses, and occasional bodies of clay. In the lower tunnel cinnabar had been deposited on the face of the boulders of ore. A small prospect opening near the dump of Tunnel X"o. 2, showed solfataric action, and formations similar to those at the surface at the Sulphur Bank mine. Bibl.: Cal. State Min. Bur., Reports V, p. 96; XIV. p. 233; Chapter rep. bien. period, 1913-1914, p. 61; Bull. 27, p. oS; Reg. of ]\Iines, Lake County, p. 3. The Maypole prospect. 7 miles west of Middletown, has been aban- doned. Bibl. : Cal. State :\Iin. Bur., Reports XIII, p. 596 ; XIV. p. 233 ; Chapter rep. bien. period, 1913-1914. p. 61. '[-"orstner. Wm.. The quicksilver resources of California: Cal. State Min. Bur.. Bull. 27, p. 58, 1903. f»2 CALIFORNIA STATK MIXING BUREAU. TIk' Middletown prospuL-t, hall" a mile suuthwest from the Jewess, has been al)andoued. Bihl.: Cal. State .Min. Buk., Report XIV, p. 233; Chapter rep. bieii. period, 1913-191-4, p. (il; Bull. 27, p. 59. Mirabel Mine (Bradford). This mine, 4 miles south of Middle- towu. wa.s opened up in 1887, as the Bradford, and later renamed ]\Iirabel, being owned by the Standard Quicksilver Company. J. ]\IcL. Harvey, Calistoga, is agent. For ten years it was one of the important producers of Lake County, but in 1897 was abandoned as worked out ; and the mine has filled with water. In 1908, a small production was reported as having been made from a clean-up around the old furnace ; and in 1916, a similar, small output was made with a concentrating table working on material from the dump and from around the furnace. The property is credited with a total yield of about 30,600 iiasks. Underground, a vertical depth of 500 feet was reached, with 22.500 linear feet of drifts, and 750 feet of shaft work. ]\Iore extended descriptions of the mine and its geology will l)e found in the references noted under Bibliography. Bibl.: Cal. State Min. Bur., Reports YIII, p. 325; X, p. 270; XI, p. 61; XII, p. 361; XIII. p. 595; XIV, p. 233; Chapter rep. bieu. period, 1913-1914, p. 61; Reg. of Mines, Lake County, p. 3; Bull. 27, pp. 60-61. V. S. G. S., Mon. XIII. p, 375; Min. Res. 1888, p. 97; 1891, p. 117; 1892, p. 160. Trans. A. I. M. E., XXII, p. 86. Red Elephant Prospect. W. G. Tremper, owner, Lower Lake. It is in Sec. 3, T. 11 X., R. 5 AV., :\I. D. M., near the Xapa County line ^ mile west of Knoxville. Only suiYicient development, mostly surface work, has been done to cover annual assessments, since its location about 1898. One shaft is down 28 feet. The ore zone is stated to be 20'-40' wide, and has Ijeen proven on the surface for a length of 300 feet. The coun- try is mainly serpentine, much of it being thoroughly weathered to an ochre. There is no reduction equipment. Bibl.: Cal. State Min. Bur., Report XIV. j). 234: Chai)1('r rep. bien. period, 1913-1914. p. (52 ; Bull. 27, p. 92; Reg. of Mines, Lake County, p. 3. Red Rock and Silver Rock Claims. Henry B. AVeipei- and Henry Schalclili. owners. Lower Lake. This group of claims located in 1916, is in Sec. 17. T. 12 N., R. 6 W.. .M. I). ]\I., 5 miles from Lower Lake, on tlie road to Alorgan X'allcy. and near the Bakci- mine. Only a small amount of diNclopment woi'k has so far been ilone. Cinnabar occurs in an ochi'eoiis leduc about 1*1 feet wide on the sni'fnce. Tliis ochreons QUICKSILVER RESOURCES. 63 material eould probably be concentrated on tables without nineh ernshiny. if a suttieient water-supply could be obtained. It appears to be from a very thoroughly weathered serpentine. The cinnabar is dis- tinctly crystalline, but mostly rather fine grained. Rich Hill Prospect. Henry liardester, IMiddletown, has a ciuick- silver prospect in Sec. 19, T. 10 N., R. 6 W., M. D. M., southeast of Middletown and i>ear the Oat Hill miiie. The ore body is stated to show 6'-7' wide, in sandstone; and a shaft has been sunk 106'. Shamrock Prospect. This group of two claims is on Rocky Creek, a branch of Cache Creek, m Sec. 23, T. 13 N., R. 6 W., about 10 miles northeast of Lower Lake. It is owned by the Shamrock Development Company (Jas. Daly, W. P. Swift et al.), Napa. The property is idle. Bibl. : Cal. State ]Min. Bur., Report XIV, p. 234; Chapter rep. bien. period, 1913-1914, p. 62; Bull. 27, p. 60; Reg. of Mines, Lake County, p. 3. Sulphur Bank Mine. Geo. T. Ruddock, owner, 433 California Street, San Francisco; Sulphur Bank Association (a co-partnership), 817 Crocker Building, San Francisco, operators under a lease and bond ; H. W. Gould, general superintendent ; N. J. ]\Iartin, superintendent at the mine. This mine is one of the notable and much written-about cpiicksilver mines of the world. It is extremely interesting from many standpoints — those of chemistry, mineralogy and geology, as well as metallurgy and mining. It was first worked in 1865 for sulphur, and in the four years to and including 1868 produced a total of nearly 2,000,000 pounds of that mineral, valued at $53,500. The property was at that time owned by the California Borax Company which dur- ing the same period was also producing borax from Borax Lake, near-by. The two are still intact and the land has been leased out as part of a cattle range for some years. During the time of working the surface cuts for sulphur, some diffi- culty was experienced in refining the material because of the presence of cinnabar, which darkened the product. The proportion of cinna- bar increased with depth. Cost of transportation to the market and a rapid fall in the price of sulphur caused a cessation of operations, but the mine was reopened and developed for its ciuicksilver in 1873, being a steady and important producer until 1883. After four years of idle- ness, work was resumed and continued until 1897, when it was again shut down. In 1899 the mine was reopened and worked until Decem- ber, 1905, the shaft being kept unwatered until June, 1906, since which time it has been idle until the r(>cent surface work herein described. As a producer of quicksilver, the Sulphur Bank mine is credited with a total output of approximately 92,400 flasks. It is said that at the o c tJJO c o o 3 •a c c o c o o c n) u 3 CO o 2 o a. QUICKSILVER RESOURCES. 65 lime of tlie last closing down of the mine (due to financial troubles as ■well as the increasino- difficulties of ventilation and pumping in conse- (|uence of the hot waters and deleterious gases) they had opened up a good body of high-grade ore underground from the Empire shaft. The Sulphur Bank is a low, rounded hill (see Photo No. 10), on the eastern shore of Clear Lake in Sec. 6, T. 13 N., R. 7 W., about 10 miles Photo No. 11. Exfoliation of basalt at Sulphur Bank Mine, due to solfataric action. Photo by Emile Huguenin. north of Lower Lake. It is also reached by launch from Lakeport. The elevation is 1350 feet at the lake level. The old surface cuts much resemble those of a placer mine with its tailings piles of boulders, except that over it all is a pulverulent, white powdery material, the result of the continuing decomposition of the rocks by the solfataric vapors and waters still present. The glare is -38540 m CALIFOUNIA STATK MINING BUREAU. almost blinding' on a sunny day. Tlie i-oiuided l)oulder.s due to concen- tric decomposition, as described by Becker^ can be plainly seen (see Photo No. 11). The evidences of solfataric activity are numerous and strikiuii'. Iron I'ails, nails, cables, etc., are sulphurized and oxidized. Wood is blackened and rotted. There are abundant sulphur crystals in crevices and flour sulphur around vents where vapors are i.ssuing. At the mouth of an abandoned shaft, now caved, near the eastern edge of the surface workings (either the Hermann shaft or Hermann air shaft — ^see Plate IX, reprinted from Bulletin 27, p. 62), hot, moist, sulphurous gases are still escaping, and under a noticeable pressure. Photo No. 12. Hot springs in bottom of "Western Cut," Sulphur Bank Mine. The odor of snl])hui' dioxide is vwy strong, so th;it it was difficult to breathe whiU' placing a lln'rnioniclcr in one of llir openings to observe the temperature. It showed lOS^ F. — tliis being at llie surface. Becker^ recorded lenii)eratures np to 17() h\ at a depth of -SOO feet. The i^ocks about llie opening and pi-otruding sticks of limber are heav- ily coated with a deposit ol' (lour snlphnr. There is a sound as of a roariiig fui'nace from beh)\v. How ;iny one eouhi bre.ithe in such an atmosphere, much less \voi-l<. is a matter for wondei-ineiit. There Avas a dead rat lying at one of the openings. .\t the npper end of the 'Becker, G. \<\. Geolog.v of the (luieU.silvcr dcpusits of the Pacilic Slope : U. S. G. S., Mon. XIII, p. 2r,6, 1888. -Op. fit., p. 259. PLATE IX. Sulphur Bank Mine. u c h e d ; s.5-.\.. \ '/' > _,Ap'U'''.,' ,'Cuf-'\ ■v*"'*. 'J C^' *!*- »MermaP Jtir Shaft / - ■ " Barron •SAa/t i''l .iiiiL'!'"' fiamoftd Shoff .^' ^ •.fill!!*- i .<^^ Scale of Projections mmi w Q I MP . --'B m m nil,/" Geological Map of Sulphur Bank Mine, Lake County. Reprinted from P.uUetin No. 27. 38540 p. 66 QUICKSILVER RESOURCES. 67 'Western Cut,' there are a number of warm springs with considerable excess gas escaping with the water— the whole having the appearance of a series of boiling cauldrons. (Photo No. 12.) The appearance is deceiving, however, as the temperatures are much lower than one would expect. The following temperatures were obtained by the writer: 84° F. ; 108"^ (water inky, with a black deposit forming about it) ; 100°; 97' (in upper corner). The Empire shaft (the latest sunk) was filled with water to within 15 feet of the collar at the time, and escaping gases were bubbling up through the water. "Tlie gases escaping from the waters are carlion dioxide, hydrogen sulphide, sulphur dioxide, and marsli gas. Tlie waters contain cliieMy carbonates, borates, and clilorides of sodium, potassium and ammonium ; but all-caline sulphides are also present."^ As to the mode of occurrence of cinnabar at Sulphur Bank, it is well summarized bv Becker,* as follows : "It does not occur in sensible quantities at or near the surface, but is found to a considerable extent mixed with sulpliur in the lower portion of the zone of oxidation. The principal deposits are below tliis level. They are found in the m.ore or less decomposed basalt, in the underlying recent lake bottom, and in the Knoxville shales and sandstones. The cinnabar is associated chiefly with silica, in part crystalline and in part amorphous. In the lava it appears as small seams, which commonly follow eitlier the original cracks between the blocks or the concentric surfaces of the decomposed masses. In the lake deposits below the basalt the cinnabar Is found as impregnations or irregular seams. In the workings from the Herman shaft the ore occurs exactly as it does in most of the quiclvsilver mines of California, more or less completely filling interstices in shattered rock masses. * * * p,. Melville has found small quantities of gold and copper in the marcasite accompanying the cinnabar. * * * The intimate association of the ore with the sulphur, opal, quartz, pyrite, and to a smaller extent with calcite, is amply sufficient to show that it has been deposited from water." Also :' "Excepting for the solfataric springs the underground mine at Sulphur Bank resembles the other principal quicksilver mines of California. * * * This fact is an important one, for it proves that deposits indistinguishable from those found in the Redington, New Almaden, and other mhies may be formed in the same manner as those at Sulphur Bank, by precipitation from hot spi'ings of volcanic origin." At the "Little Sulphur Bank," above ^ mile south of Borax Lake, some jjrospectiug has been done. Here, the same sulphurous odors are noticeable as at Sulphur Bank. The property was formerly equipped with a Knox-O.sborne 25-ton furnace, 3 Hiittner-Scott furnaces of 40, n and 30 tons, respectively, and a battery of 9 'D' retorts. Some ((uicksilver was produced during 1915, 1916, and early in 1917, before the present operators began work, by retorting material obtained in tearing down the old furnaces. The present operators built a concentrating plant, utilizing a revolv- ing screen and 4 Deister-Overstrom tables, which they have been using as a test-unit to work out an ore-dressing scheme for the material in the extensive dumps. This plant and its accomplishments up to the time of the author's visit (September, 1917) are described in detail in the section of this bulletin on Metallurgy." As there recounted, much difficulty was experienced in rctoi'ting the concentrates on account of the considerable percentage of native, free sulphur present, forming a •'Becker, oiJ. cit., p. 4 63. ^Op. cit., p. 2^7. '^Op. cit., p. 263. '•See D. 3 4 6, nnat. 68 CALIFORNIA STATE MINING BUREAU. matte witli tlie iron of the retorts. Two 12-pipe banks of Johnson- McKay retorts were then in use, and a battery of 4 'D' retorts was beino- built. Oak and manzanita were being used for fuel at a cost of $4.50 per cord at the retort, divided as follows : $2 cutting ; 50^'- stump- age; $2 hauling. This was expected soon to increase. An assaying j and chemical laboratory is maintained, and the various products are sampled, so that a careful watch is kept on all of the current condi- tions and developments. Since the mine was visited, we are informed that a revolving furnace is being installed, which it is hoped will solve the roasting difficulties. For the present at least, no undergrouml work is planned, there being several hundred thousand tons at the sur- face, estimated as material available for treatment l)y the proposed methods. Practically all of the dumps in sight (see Photo No. 10 i and some over the hill on the north side, have concentratable values in cinnabar. The material can be cheaply excavated with a steam shovel and transported to the mill by motor trucks, as it will have to be moved distances up to i mile and raised to the top of the mill bin. The development of their scheme of ore-dressing and reduction here will be watched with much interest. Bibl.: Cal. State Min. Bur., Reports IV, pp. 157, 330, 336, 339: V, p. 96 ; VI, Part I, p. 136 ; VIII, p. 324 ; X, pp. 238, 239 ; XI, p. 63 ; XII, p. 363 ; XIII, p. 597 ; XIV. pp. 234-238, 240 ; Chapter rep. bien. period, 1913-1914, pp. 62-66, 68; Bull. 27, pp. 61-70; Reg. of Mines, Lake County, ]). 3. U. S. G. S., :\Ion. XIII, pp. 251-270, 463; Min. Res., 1883, pp. 394-397; 1884, p. 492; 1892, pp. 146, 148, 160; 1902, pp. 251, 252; Water Sup. Pap. 338, pp. 98-99. Geol. Surv. op Cal., Geol., Vol. I, p. 99. Trans. A. I. M. E., XXIII, pp. 225 ct seq.: XXXIII, p. 751; Genesis of Ore Dep., pp. 32, 66, 256. JMin. Res., W. of Rocky Mts., 1868, p. 266; 1876, p. 20 Am. Jour, of Sci., Vol. XXIV, 3d Ser., pp. 23 et seq. Thorn Mine (Bear Canon). It is west of Middletown. in Sec. 36, T. 11 N., R. 8 W., near Anderson Springs ; Thorn Bros., owners. Only assessment worl< was done foi- several years, but it is said no ore bodies of consequence have Ixmmi (h'velo])e(l. In 1909. a small production was repoi'tcd from oi'i' taken out during development work, but notli- ing has been done since. Bibl. : Cal. State ]\Iin. Bur., Report XIV, p. 239 ; Chapter rep. bien. period, 1913-1914, p. 66; P»ull. 27. p. 70. U. S. G. S., :\rin. Res. 1909. I 'a 1-1 T. p. 5.52. j Utopia Mine. The Utopia is on Hie eastern shore of Clear Lake in Sec. 25, T. 15 N., K. !) W., near Bartlett Landiu-. northeast from Lake- i QUICKSILVER RESOURCES. 69 port. It is owned by the Utopia Quieksilver .Mining Company of Lake- port ; A. Spnrr, secretary. It has not been operated in recent years, as it is said they were driven out by water, the orebody running- under the lake. Bibl. : Cal. State Mix. Bur., Reports XIII, p. 597 ; XIV. p. 239 ; Chapter rep. bien. period, 1913-1914, p. 67; Bull. 27, p. 70; Reg. of Klines. Lake County, p. 3. Wall Street Mine (originally Cincinnati).^ This mine was a pro- ducer as early cis 1875, about which time it was patented, but aban- doned by the original owners in 1878. The present owner, W. H. Par- sons, acquired the property in 1898, by purchase of tax title from the State, and has been reporting an output of a few flasks of quicksilver annually for the past twelve years. It is located in Sec. 1. T. 10 N., R. 8 W., on a branch of Dry Creek. 6 miles west of ]\Iiddletown. The elevation is 2275 feet (bar.) on the road at the retort. The property includes the Kearsarge group of 3 patented claims, whose principal value is for water supply and timber. The old workings are largely inaccessible. The owner works the mine single-handed, with occasion- ally an additional man, assisted by a packhorse for handling ore, tim- bers and firewood. The Wall Street mine is about ^ mile down the canon from the Helen mine ore-body from which it appears to have been broken by a northeast-southwest fault. Their main mineralized ledges have several characteristics in common and are marked by sim- ilar, prominent outcrops. The Wall Street, however, has a consider- able proportion of native ciuicksilver which does not appear at the other. There is a narrow quartz vein in the main ledge near its hanging-wall side, and parallel to its dip — 30° SW. The vein, which has a comb structure, carries in its numerous cavities and pores much native metal. Parsons states that the serpentine from 1 to 3 feet above and below the quartz carries some 4% of both native metal and cinna- bar in about equal proportions. The silicified ore-bearing serpentine lies above the softer serpentine and carries the quartz vein, cinnabar, pyrite. and lenses of jasperoid. In the mill there is a 20 h. p. Westing- house compressor (being a locomotive air-brake pump, 9^' diam. x 10" stroke), steam driven, which furnishes power for an air hammer drill in underground work. There is also a small Chilian mill, and two homemade, table concentrators, said to have a capacity of 3^ tons per day. Some of the soft ore is concentrated, but the jasperoid and dis- seminated ores are retorted direct. One 'D' retort is used — 14 inches high, 30 inches wide and 8 feet- long — which consumes 1^ cords of fire- wood per flask of quicksilver produced. This retort has a capacity of 'Whitney, J. D., Geolog5- of California: Geol. Surv. of Cal., vol. I, p. S9, 1865. 70 CALIFORNIA STATE MINING BI'REAU. I 600 pouiuls ol ore per day. Tlic old coinpany is said to have expended ' $100,000 and pi-odneed 1-iO flasks. The total ontpnt to the end of 1917 has been approximately 350 flasks. Bibl.: Cal. State Min. Buk.. Report 1\'. p. 183; V, p. rcpoi-ted' at Point Reyes, but no commercial development has taken i)lace there. There is an occurrence of low-grade cinnabar-bearing material near San Rafael (?). From samples shown* the wi'itoi-. it appeal's to have been a silicified serpentine, now nuu-h oxidized and wi'athert'd. 'Mill. & Sci. Press, Feb. 27, 1S75, p. 130 ; also in U. S. G. S., Mon. XIII, p. .^7fl. (^L'lCKSIl.VEK RESOURCES. 71 MARIPOSA COUNTY. There is a 6-inch quartz ledge on the Merced River near Coiilterville that has a X.-S. strike, and oarries on its footwall side a thin seam of qnartz containing crystallized cinnabar. It is not in sufficient quan- tity to be of commercial value for quicksilver ; but it is stated that Chinese between ISoO and 1860 utilized crystals from this vein for ver- milion. Bibl. : Cal. State Mix. Bur., Report XIV, p. 602: Chapter rep. bieu. period. 1913-1914, p. 176. U. S. G. S., Mon. XIII. p. 383. Geol. Surv. of Cal.. GeoL, vol. I, p. 230. MENDOCINO COUNTY. Occident Mine (originally Amrillo — ? Amarillo; also known as Wise's Mine). W. H. M. Smallman, owner, 560 Powell Street, San Fram-isco. It is in Lot 39, Sec. 6. T. 12 X., R. 11 W., M. D. M., 7 miles southwest of Ilopland, and 4^ miles from the State Highway. It was originally located in the 70 's under the name of Amarillo (the com- pany's stock certificate read 'Amrillo'), but patented in 1883 as the Occident. Local legend says that the mine was worked by the Mexi- cans before the American occupation. There are various dumps and other evidences of old workings. Some work was done on this prop- erty in 1875, and again for several years preceding 1907. The only definite record of commercial output is 50 flasks in 1906. There has been no work done since, except a small amount of prospecting. The ore was retorted. IMost of the workings are now caved. The ore is in an ochreous, weathered serpentine material, similar to that found at so many of the quicksilver mines in California. Opaline silica is asso- ciated. The formation is considerably brecciated. Some further development work will be started this spring. Bibl. : :\Iix. Res. W. of Rocky Mts., 1875, p. 1-1. U. S. G. S., Min. Res.. 1906, p. 492 ; 1907, Part I, p. 679. 72 CALIFORNIA STATE MINING BUREAU. MERCED COUNTY. The Staytoii quicksilver district is at the junction of San Benito, Santa Clara, and JNIereed counties. Portions of some of the proper- ties are on the Merced side of the county line; but as tlie principal groups and workings are in San Benito County, they are described under that heading. MODOC COUNTY. Modoc Cinnabar Group. A. H. Dixon and Charles Kirkpatrick, owners, Lakeview, Oregon. This recently located prospect is 'Sh miles southeast of Willow Ranch station on the Nevada-California-Oregon Railroad, and close to the main county road, at an elevation of about 5000 feet. The country rock is stated to be volcanic and the vein of soft gouge-like material 18"-20" wide, carrying cinnabar. There is a good supply of timber and water at hand. Development work has just begun, and a small retort built. Dixon states that the material so far tested in the retort yielded from 6 to 8 pounds of quicksilver per 100 pounds of ore. Quicksilver ore has also been reported 25 miles southeast of Cedar- ville, but there has been no work done recently. Bibl. : U. S. G. S., Min. Res.. 1902, p. 252. MONO COUNTY. In the Museum of the State Mining Bureau, there is a specimen (#10340) of ore showing beautiful cinnabar crystals, from 5 miles NNE. of Bodie. The material is high grade. The gangue mineral appears to be mainly calcite, and there are some globules of native mer- cury present. The country rock is apparently an altered igneous or metamorphic rock, as there are a couple patches of ehloritic mineral attached to the specimen. In the locality to which this specimen is credited there is a small plateau of volcanic material underlain by meta- morphic rocks. There has been no commercial development of this quicksilver occurrence. Bibl. : Cal. State ]\Iin. Bur., Bull. 67. p. 35. QUICKSILVER RESOURCES. 73 MONTEREY COUNTY. The quicksilver properties in ^lonterey Coiuity from wliieli eom- iiiercial production has thus far come, are a.ssociated with the area of serpentine near Parkfiekl in the southeastern corner of the county. Nearly the entire output of the district, 530 flasks, to date has come from one mine, the Patriquin. Several quicksilver prospects have been reported in the southwest corner of the county, north of ^Mount ^Mars near the coast, and north- west of the producing districts of San Luis Obispo County, but little development work has ever been done there. Dutro Mine. F. D. ]Martinez, owner, Santa Maria. It is at the head of the west fork of San Carpojaro Creek in the SW. ^ of SE. ^ of Sec. 28. T. 24 S., R. 6 E., M. D. :\r. Idle for sevearl years; 100' shaft and 40' drift, caved. Bibl. : Cal. State ]\Iix. Bur., Report XY, 613 ; Chapter rep. bieu. period, 1915-1916, p. 19 ; Bull. 27, p. 124. Monte Cristo Group. AY. D. Cruikshank et al., are reported to have located quicksilver claims near Gorda. So far only assessment work has been done. Patriquin- Gillett Quicksilver Mining Company. Henry Ludeke, Jr., owner, Parkfield ; Lewis & A. G. Patriquin, Nathan Gillett, lessees. It is on agricultural patented land in Sec. 1, T. 23 S., R. 14 E., M. D. M., 5^ miles north of Parkfield at an elevation of 2400 feet (U. S. G. S.). The ore body is a southeasterly continuation of the mineralized zone of the Patriquin mine which is above it on the same ridge to the north- west of Table Mountain. There is a black 'alta' on the footwall, and the vein shows a width of 6" to 3'. There are 6 or 7 crosscuts having lengths up to 35', with a total of 150' of work. Reduction equipment consists of a 'D' retort built in April, 1917, and which is operated occa- sionally. A few flasks of quicksilver were produced in 1917. Patriquin Quicksilver Mine (one time called Pitt; also Cholame- Parkfield; and Parkfield). Louis, A. G. & Mrs. L. S. Patriquin, and J. AY. B. Anderson, owners, Parkfield. This group of four claims and two fractions is in Sec. 2, T. 23 S., R. 14 E., 6 miles north of Park- field; elevation 3000' (bar.) at the middle tunnel. It was first worked about 1873, by a Mr. Pitts, who is said to have produced 60 flasks of quicksilver, using a small mud-plastered furnace. In 1913. about $6,000 worth of development work was done by a lessee, but no ore reduced. The mine has now been in steady operation since its reopening in 1915. It is credited with a total production of 511 flasks to the end of 1917. 74 Cx\LIFORNIA STATE MINING BUREAU. The ('ountry rocks nrv serpentine jiiid Franciscan metamorpliic sand- stone. 'I'he ore body is a zone eontaining parallel stringers of cinnabar with the intervening rock and ils fractures more or less impregnated with the mineral. It is in part sleckworls. The vein tilling is quartz, opaline siliea, and ehaleedony, and iiuu-h of the serpentine is silicified. The cinnabar occurs mainly in tiie fractures, as distinct crystals, not as 'paint.' There i.s also some metacinnabarite, pyrite. and calcite asso- ciated. There are two ore zones with a ridge (see Photo. No. 13) of serpentine between them, the north one being 100' wide, and the other Photo No. 13. Patriquin Mine^ near Parkfield, Monterey County. Mine on ridge in back- ground ; retorts in foreground. wider. The strike is N. 73" AV., and tlie dii) a1)ont (15"^ X. In these areas the surface soil yields einnahar by panning. On tlie south vein at the west end, an old tunnel in 800' is stated to cross-eut six shoots, none of which hnvc l)cen drifted on. Thei-e is anothci- adil in *).")()'. 500' of which is ;i drift. The oi-e of the south vein is harder and less oxidized. On the north vein, the mi(hlle adit crosscuts tlie ore zone for over 100'. Most of the pi-oduct ion to date has come from the north side. The ore i.s extracted by adits aiul stopes. and the workings are somewhat ii-regular, because of following the high-grade shoots in ord(M' to maintain a i-etoi'ting grade. There is much material being left which would pay to put througli a large rurnace. it seems a pity to gouge QUICKSILVER RESOURCES. 75 a property like this for a retort, when with a Scott furnace or other large-capacity plant, the mine could be systematically developed, more cheaply operated, and its life doubtless prolonged. Some of the shoots have been stoped out up to 10 feet wide. The coarse ore. being mostly low grade, is sorted out onto the dump and the fine ore with occasional high-grade lumps is trammed to the retort. Water is obtained from a spring and the lower tunnel ; but most of the mine workings are dry. Reduction equipment consists of 2 banks of Johnson-McKay 12-pipe retorts (see Photo No. 13; also Photos 43 and 62, post). No water is used for cooling the condenser pipes, yet they keep cool except for the first 2 feet next to the retort. This feature is discussed elsew^here herein under the section on IMetallurgy.^ AVhen visited they were charging 3 scoops per charge per pipe, each pipe being charged twice a day, or 240 pounds of ore per pipe per 24 hours. The nearly 3 tons of ore treated per day by the two banks was yielding 1^ to 2 flasks of quicksilver or a content of 2%-2.6% mercury. About 200 pounds of lime per week was being added, at a cost of $3 per bbl. (180 lb.) delivered at the retorts. Wood costs approximately $5 per cord at the retorts, and an average of 1^ cords are consumed per. 24 hours (less of oak, but more when using pine). The condenser pipes are scraped out every other day — i.e. 1 bank each day — and about ^ flask of metal obtained thereby each time. iMost of the metal is stated to condense in the upper part of the pipe, and soot forms at about a foot from the retort. Samples of the burned ore are panned occasionally and are stated to show a fairly clean extraction. Nine men are employed, including 3 at the retorts. Bibl. : Cal. State Min. Bur., Report XV, p. 613 ; Chapter rep. l)ien. period, 1915-1916, p. 19; Bull. 27, p. 123. U. S. G. S., Min. Res. 1915, Part I, p. 269. Table Mountain Claim. G. W. White, owner, Parkfield. This pros- pect is on Table Mountain in Sec. 30, T. 23 S., R. 16 E., about 9 miles east of Parkfield; elevation 3000' (U. S. G. S). Cinnabar occurs with opaline silica in serpentine. Idle except for assessments. A 12-pipe retort was built in 1916, and two or three flasks of quicksilver pro- duced. Bibl.: Cal. State Min. Bur., Report XV, p. 614; Chapter rep. bien. period, 1915-1916, p. 20 ; Bull. No. 27, p. 124. 'See r>. 257, post. 76 CALIFORNIA STAI'i: MINING BUREAU. NAPA COUNTY. Development work began on the quicksilver mines of hotli the Knox- ville and the Pope Valley sections about 1860. In the former, the Lake mine (afterward merged with tlie Manhattan) was the pioneer, fol- lowed closely by the Redington mine; and in the latter district, the Val- ley mine (now a part of the ^tna mineral springs property) was the first. Although the industry has had its ups and downs, Napa County was one of California's most important quicksilver producers from 1864 to 1903, from which later date the decline was very rapid until the present revival. The available published records show for Napa County, to the end of 1917, a total value of quicksilver produced of practically $15,200,000. That tliis value is below the actual output is known, as the product of some of the mines was included in the earlier reports of the state's production, under 'various mines.' In fact, the Knoxville mines alone are said to have yielded $17,000,000 in quick- silver, while Oat Hill is credited with another $5,000,000, to say noth- ing of the ^tna and others. The following tabulation gives the recorded production of quicksilver in Napa County, annually since 1863 : Quicksilver Production of Napa County. Year Flasks Value Tear Flasks Value Manhattan Mine output 1863 to 1876 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 187.5 1876 1877 1878 1879 1880- 1881 1882 1883 1884 1885 1886 1887 1888. 188!) 3,594 444 852 2.714 3,545 2,2.S4 7,862 9,808 6,598 5,766 4,098 4,876 5,266 11,705 9,453 11,303 13,127 10,810 9,446 6,830 7,746 9.013 7,784 5,188 3.891 5,656 6,247 5,150 5.402 $235,876 16,139 35,852 124,573 162.716 119,755 360.866 4.50,187 302,848 330,853 258,584 321,475 423.018 1.231,1.32 795,470 497.332 489,637 355,649 281,961 211.730 231.063 2.54,467 223,790 158,234 119,frl8 200,788 2r>l,717 218,875 243,090 1890 1891 1892 1893 . 1894 1895 . 1896. 1897. 1898. 1899. 1900. 1901 1902 nm . 1904. 1905. 1906. 1907. 1908 1909. 1910. 1911 1912 1913. 1914 1915 . 1916. 1917. 3,934 4,896 8,612 11,505 9,705 9.318 11,411 12,281 12,368 11,696 8,724 7,798 7,142 7,859 *o,328 4.853 2,.380 2,500 2,340 1.625 6-16 140 287 287 240 .507 1,150 834 Totals. 336,794 $206,535 221,544 350,595 422,809 298,016 372,500 403,031 459,753 472,972 598,322 403.500 388,176 3l>4,474 333,006 199.586 171,910 86,870 95,400 98,912 80,535 29,231 6,441 12.065 11,546 11.772 45,224 107,525 78,320 $1.5.190,895 •Flasks of 75 lb. since June. 1901 ; of 70 J lb. previously. QUICKSILVER RESOURCES. 77 ^tna Quicksilver Mine (foniR'ily iEtna Consolidated, one time oalled Pope Valley). Lawley Brothers, owners, Calistoga ; California Mines Development Corporation, lessee, 441 Monadnock Bldg., San Francisco; E. B. De Golia, president; E. B. Frost, superintendent. The ^tna group is at the southeast end of the Mayacmas district near the head of a branch of Pope Creek, on the ridge separating it from James Creek. It is in Sees. 2 and 3, T. 9 N., R. 6 W., 2 miles southeast from the Oat Hill mine and 9 miles northeast of Calistoga, though St. Helena (18 miles) is its railroad shipping point on account of better roads and easier grades. Post office is .Etna Springs. The group con- sists of Phoenix, Silver Bow, Red Hill, Washington, Pope, and Star claims, all patented. Quicksilver ore is said to have been discovered here in 1854 by Lawley; and the property was operated in 1863 by the Hamilton Quicksilver Mining Company.^ It was later sold to Hauf- meister et al.. then to the .Etna Consolidated Quicksilver Company; then in 1904 to the present owners. The earliest production was from the Phoenix. The most important producing periods of the .Etna group were between 1877 and 1887, and for about six years beginning with 1892. The available records credit this group with a total output of at least 45,580 flasks to the end of 1917. The last two or three years that the .Etna Consolidated Company had the mine mainly prospect- ing was done. In 1910-1912, a small production was made from clean- up by lessees around the old furnaces, and the retorting of small lots of sorted ore. Concentration operations at the ^tna mine during 1913- 1917. under the Soderhjelm and Gibson leases are described elsewhere herein- under the heading of ]\Ietallurgy. In addition to their concen- trates, the lessees retorted occasional lots of sorted ore from the mine. Late in 1916, the 60-ton Scott furnace was rehabilitated. The present company has been operating the property since September 1, 1917. Extended descriptions of the geology and the underground workings are given by Becker" and by Forstner.* According to the latter: "The serpentine in this region appears to be underlaid by sandstone, being a brealc above tunnel No. 2 in the Phoenix claim. Tunnel No. 7 runs toward a basalt dike, which breaks through to the surface, and reaches the contact at a depth of from 800 to 1000 feet. This dike shows at the surface for a length of about 1000 reet ; the imderground works [in the Silver Bow claim] which run around the dike show it to be .surrounded by sandstone. The basalt is cut off at the surface by the same serpentine showing" at tunnel No. 2 ; "but fi'om the fact that the latter does not go through the sandstone, the surface indications are not convincing that this basalt dike does not connect with the main seat of eruption, having uplifted the serpentine and broken through the sandstone. The tuff surrounding the basalt is more siliceous and probably older than the basalt. It overlies the sandstone but not the serpentine, confirming the above supposition. The tuff overlying the serpentine has probably been eroded. For some reason, in this region tlie tuff is invariably found overlying the .sandstone but not the serpentine. In the Star claim another short dike of basalt, about 100 feet long, has been followed at its contact with tlie sandstone to a depth of 600 feet. ■Whitnev, J. D., Geology of California: Geol. Surv. of Cal., vol. I, p. 91, 1865. =See p. 336, twst. "Becker, G. F., Geologj^ of the quicksilver deposits of the Pacific Slope: U. S. G. S., Mon. XIII, pp. 354, 371-374, 188S. was found. In the Phoenix workings, at tunnel No. 9, only sandstone was found underground in the Red Hill, while tlie surface of that claim is almost entirely co\<"red by serpentine .ind its allied opaline rock; a winze simk from this tunnel follows a contact between igneous rock and san the rurnace bins, withonl reipiiriiig the wagon haul. QUICKSILVER RESOURCES. 79 The rediietioii equipment euusisLs of a (iO-toii Seott tiiie-ore t'uniace to which are connected three series of condensers. The first series is of l)riek. consisting of 10 compartments, each 14'x38'xl2' average heii^lit ilhc top being sloped). Next is a series of 10 cast-iron chani- l)(>rs similar to the Knox-Osborne type, 3' wide x 9' long x 5' and 4' liigli. the slope being on the bottom; with an interior bafHe extending 2/3 of the way down from the top ; and connected by vitrified pipe (see Photo No. 64, post). The third series consists of 2 rectangular, wooden chambers 10'xl8'x9'. The fuel used is wood. The blower is ^m 'J^lt^msmmiim.^ .9 *• * ae.' Photo No. 14. Bins and furnace plant at the .ffitna Mine, Lake County. driven by a 1^ h. p. gas engine banks-^Morse, type Z, 350 r. p. just below distillate, at a cost grade soot from the condensers residue washed over riffles and were 30 men employed, miners $3.00. Bibl. : C.\L. State :\[m. B p. 362; XITI. p. ,597; period, 1913-1914; pp. G. S., Mon. XIII, pp. and the rock breaker by a 15 h. p. Fair-, m., oil engine, using a grade of fuel oil of 60f*-70^' per 8-hour day. The high- is worked on an inclined plate, and the through a series of baffle boxes. There being paid $3.50 per day, and muckers UR., Reports V, p. 96; XI, p. 72; XII. XIV, pp. 284-286; Chapter rep. bien. 111-114: Bull. 27, pp. 72-76. U. S. 354, 371-374; IMin. Res. 1884, p. 492; 80 CALIFORNIA STATE MINING BUREAU. 1892, p. 148; 1902; p. 252; 1909, Ft. I. p. 553; 1910, Ft. I, p. 698; 1911, Ft. I, p. 901 ; 1912, Ft. I, p. 942 ; 1913, Ft. I, p. 205 ; 1914, Ft. I, p. 326; 1915, Ft. I, p. 269. Mm. Res. W. op Rocky Mts., 1872, p. 523; 1873, ]). 11 ; 1S74. p. 30; 1876, p. 20. Geol. SuRv. OK Cal., Oeol. vol. T. ]). 91. Exo. & ^Min. Jour., Nov. 1, 1913. p. S28. ^tna Extension Claims. Chas. A. Lawley, owner, Calistoga, It is on tlie soutli side of James Creek, adjoining- or near to the JEtna gTonp, being in SE. ^ of SE. ] of Sec. 33, also S. ^ of SW. J and Lot 2 of Sec. 34, also Lots 1 and 2 of Sec. 35, all in T. 10 N., R. 6 W., M. D. M. In January, 1916, this property was leased to D. S. Llewellyn, but there is no record of any quicksilver being produced and it is now idle. Apparentl,y only a small amount of development Avork has been done. Bella Union Mine. Bella Union Quicksilver Company, owner; AA^ H. Hamilton, attorney. No. 556 Mills Building, San Francisco; Rutherford Mining Company, lessee ; II. A. Broughton. manager, Rialto Building, San Francisco. This group includes the Bella Union and Oakvilie mines in Sec. 20, T. 7 N., R. 5 W., M. D. M., just on the edge of the Napa Valley, 1| miles west of Oakvilie; elevation 500 feet. The Oak- vilie was a producer in 1872-1873 (about 400 flasks) and the Bella Union is credited with 271 flasks in 1876; but the exact total figures are not available. The total output to date for the group has been at least 825 flasks. The ore carries cinnabar with pyrite, quartz and cal- cite in serpentine, largely, and a metamorphosed rock (possibly a sedi- mentary) which seems to be in process of serpentinization. Chlorite, an end product of the weathering of the serpentine, is noticeably pres- ent. The cinnabar is coarsely crystalline and massive, occurring in part as veinlets. The strike of the vein appears to be W. of N., and the dip is about 40° W. In the winter of 1909-1910, under a working bond for tlie purchase of the mine, certain of the old tunnels were re-opened, exposing some good ore; but the contract lapsed for failure to continue operations. Early in 1916, tlie mine was again leased, and has boon oporatod at inloi-vals since, being at present (March, 1918) idle. Iji 1916, the two old Neate coarse-ore furnaces (see Fhoto No. 46, post) were repaired and used for a short time. This was followed by concentration orpiipment. First, tables were tried ; then, flotation ; and finally, the Iwo combined. Willi tli(> last-named, the installation included a bali-mill. K. & K. eii'cular. tlolation machine, and two Deister-Overstroin lablos. The undei-llow of the K. & K. machine went to the tables, and the overflow froth with its concentrate was carried by a launder to a sellling tank. The plant was driven ])y a 20 h. p. West- QUICKSILVER RESOURCES. 81 ern isras engine. The concentrates were roasted in a 10-pipe Johnson- I\rcKay retort, l)ui'nin,L;' wood. Following the shutting-down of this plant, the retorts were run for a time on sorted ore, and 6 men Avere employed. "When visited by the writer in September, 1917, a Lillard furnace (a vertical, continuous-feed retort) was being built. ^ It is stated that at present (March. 1918) the property is idle. Bibl. : Cal. State Min. Bur., Reports IV, p. 336 (table) ; X, p. 362; XII, p. 364; XIII, p. 599; XIV, p. 286; Chapter rep. bien. period. 1913-1914, p. 114; Bull. 27, p. 76. U. S. G. S., Mon. XIII. p. 377; Min. Res. 1909, Pt. I, p. 553; 1915, Pt. I, p. 269. Min. Res. W. of Rocky Mts., 1873, p. 11 ; 1874, p. 30. Calistoga Hot Springs. There is a flat, semi-marsh area of 200 acres or more on the eastern side of Xapa Creek at Calistoga, in which hot sulphur springs occur. It is only necessary to dig down a foot or two anywhere in this area to get hot water. In places, the mud is said to have shown native quicksilver on panning.^ Corona Mine. Vallejo Quicksilver Mining Company, owner; J. B. McCauley. president; E. J. ]McCauley, secretary, 409 Carolina St., Vallejo. It is in Sees. 32 and 33, T. 10 X., R. 6 W., 9 milas southeast of Middletown, between the Oat Hill mine on the northeast and Twin Peaks mine on the south; elevation, 2200 feet (barometric reading). The Corona was opened up in 1895, but closed down in 1906, follow- ing a heavy winter, being driven out by w^ater in excess of the pumping capacity. They also had furnace troubles on account of the large amount of pyrite occurring with the cinnabar. The pyrite rendered the ore self-burning, making it difficult to regulate the furnace temper- atures, and the condensing. A white powder (probably sulphate of mercury) formed as an incrustation in the condensers, the result of reaction between the released quicksilver and SO3 gas. This incrusta- tion had to be broken out and retorted. The furnace, of the Scott type, with the walls built in part of volcanic tuff quarried nearby, is of 50 tons capacity. The mine has since been idle except for some production made in 1916 by retorting ore taken out in the course of prospecting work during that year. Figures of the total output of the Corona are not available, but it is claimed to have been approx- imatelv 5000 flasks. 'See D. 217, nost. -Cal. State Min. Bur., Report XIII, p. 514, 1896. 6— .3S540 82 CALIFORNIA STATE MINING BUREAU. The Corona mint' is on llir contact of the Oat Hill sandstone and a serpentine belt (see Plate X). According to Forstner,' who visited the mine when it was open and in operation: "The ore occurs in & zone of black chert rock, lying between a sandstone footwall and probably a serpentine hangins wall. The general strike of the zone is N. 4.")° W. Three ore slioots sliow at the suiface. Tlie development consists mainly in a level which enters the hill running very nearly west and cross-cutting tlie sandstone foot- wall for about 4 00 feet. The sandstone here is mixed with some shales. At 4 00 feet, the tunnel cuts the vein and follows it about 800 feet to the southeast, and 1300 feet to the northwest. The tunnel cuts the vein at the southeasterly ore slioot, witli about 130 feet of backs. The workable ore body here is from 10' to 15' wide, the cinnabar forming in fissures running through the opaline rock. Underlying the latter is a white talc, wherein pieces of white and gray rock are found, determined as plitlianite, indicating that originally a body of shales overlaid the sandstone and were silicified, probably by the same solution wliich formed the overlying chert beds. Tliis ore shoot has in tlie "past produced some lich one, * * * ; development work being central- ized on the middle ore shoot, wliich tlie tunnel cuts at a depth of 350 feet below the suiface. A vertical shaft, 100 feet deep, has been sunk from the tunnel level on this shoot. The tunnel is driven northwest to cut the third ore shoot. Part of the tunnel is driven nortliwest to cut the third ore shoot. Part of the tunnel is run in the sandstone footwall, determining its persistency, but no crosscut has been run into the hanging wall. A very soft decomposed material overlying the ore body was crosscut to a width of 35 feet, without finding unaltered material; hence the assump- tion of a serpentine hanging wall rests on surface indications. The black chert wherein the ore makes is from 40 to 45 feet wide; * * * The centr.al ore shoot has been opened for a length of 160 feet, and has been persistent in depth from the surface to the present depth of 450 feet. The cinnabar forms occasionally in such hard and compact material that it can scarcely be understood how it found access to its place of deposition." Bibl.: Cal. State Min. Bur.. Keports XIII, p. 597: XIV. p. 287; Chapter rep. bien. period, 1913-1914, p. 114; Bnll. 27. pp. 79, 206, 207. U. S. G. S., Min. Res., 1902, p. 252; 1908. Pt. I. p. 686. James Creek Placers. Several men, operating in a small way with rockers have, during the past three years, been concentrating cinnabai' from the stream gravels in James Creek for several miles below the Oat Hill mine and in part near Aetna Springs. This material has come largely through erosion by winter rains of the extensive Oat Hill dumps during their exposure of many years. Lindblom Bros., leasing on land owned by Mrs. M. Patton, Calistoga, just below Oat Hill, have been the principal producers by this method. In 1916, they (two men) were making as high as 30-40 pounds of concentrates per 8-hour day, which yielded 309^-40% mercury in a retort consisting of two 4" pipes. Among those working farther down the creek and near -^tna Springs Avere : A. IMarro, Joe Paulishich, Bert and Henry Wells. Knoxville Mine (Boston, Redington). Beiryessa Cattle Company, owner; George Holcomb, president, Keno, Nevada; C. S. Wheeler, sec- retary. It was recently sold to the present owners by F. E. Johnston of Napa who had owned it since the Boston company ceased operations. This mine, known for years as the Redington, and later as the Boston, was finst called 'Excelsior'- being owned liy the X. L. C. R. Alining Company. It was discovered in cutting a grade for a highway, and 'Op. cit., p. 79. =Whitney, J. T)., Geology of Califoinia ; Ceol. Surv. of Cal., vol. 1, p. 02. 1S65. X 5 a ^ ^ H 5: < ft If fi ^ Ji ^7 / 1 11 ° 1 1 / ^. ) Jhy. / /i/r^SF \\7 V i \ /~j? y? / / / ^' ^ _J / / ^ W^ ^ II (( ' »i \l^ W-_ ^\ /■ 4 / ^^ J / 7 ci / 's / °^ 1 / ii tf / ^ f / ^ V /" g ^> / J ' : L ^ '^^ ^ ^ 1 1/ S ^ -^ ^' . 1 /^ ^' •• > i^-^ -On 1^ /::,.: ->! -< 1 7i3 west ui' Oakville. by a road wliicli is fair in suiinnt r. Imt lira\'y in win- ter. The property consists of 11 claims and li'actinns. all patented, divided into two gronps known as La -loya Consolidated Mine and La Jnya %2 Consolidated. I'espectively ; a total aica of 1S4.5S acres. Tlie Accident claim at tlie west end of the first-named ut'onj) is nndei- lease to Frank Hooks. ()ak\'ille. who. in Seplember. IIMT. had :!!• feet (d' tun- nel di-iveii. with some cimiabar showing in a siliceous ganuue. The La 'Joya property had been idle many y(>ai's. but was i-eopened in 1915, the present opei-alors takim:' charge in .hd.\. 1916. A total of 405 tla.sks QUICKSILVER RESOURCES. 85 of quicksilver have been produced to the end of 1*?17, not including the earlier day operations, as those figures were not segregated. The vein is in a nmch-altered serpentine, bnt there is a contact with sandstone nearby. The strike is uorthwest and the dip southwest rather tiat ; average width 6', but iu the 'Big Stope' it is np to 6 sets (36') wide. There is another, smaller vein ir the hanging w^all. The cinnabar is mostly crystalline, with a little pyrite, and the gangue is largely siliceons, both chalcedony and quartz being present. Chlorite, characteristic as an eud product of the weathering of serpentine, is Photo No. 15. Furnaces at La Joya Mine, Napa County. Fitzgerald furnace in buildings at left; Livingston at right; and retorts on bench between. abnndaiit. A little native mercury has been noted. The main adit was driven 820' to crosscut the vein, which has been drifted on for a length of 400 feet. (See sketch map, Plate XL) This is at a depth of 2.50'-300' below the ontcrop. Ore is being broken by raises and stopes. A Fitzgerald furnace was bnilt some years ago. This was suppos- edly an inclined retort.^ but it appeared to the Avriter to have been oper- ated like a Livermore furnace, with the flames passing along the top of the ore instead of outside the ore-chamber as designed. This furnace in March-lMay, 1917, was treating 6 tons per day with a yield of 1 flask of quicksilver daily. It is stated that at first there was condensation of quicksilver in the upper part of the ore chamber, following which a =See p. 216, post: also Forstner, op. cit., pp. 201, 305. 86 CAIilFORNIA STATE MINING BUREAU. blower was added. ]\Iore quicksilver was thereafter recovered and the capacity of the furnace was increased, hut the stack loss was also noticeably increased as shown by a gold-piece test of the escaping gases. From retort tests, the ore then being treated was estimated to carry 1% Hg; and a sample sent to the writer, assayed 2% Hg. A 12-pipe Johnson-lMcKay retort was built, and utilized the greater part of the year 1917. This treated 3 tons of ore, daily. A pipe was dis- charged and refilled every 45 min., giving a 9-hour cycle; and 3/4 cord of wood was consumed per 24 hours, at a cost of $6.50 per cord. Wood is obtained from the surrounding hills and packed in by burros. When visited by the writer in September, 1917, a Livingston furnace,' calculated to treat 20-25 tons per day was being installed (see Photo No. 15). We are informed, its use has now (IMarch, 1918) been dis- continued, as it did not prove satisfactory. In September, 1917, 24 men were employed, of whom 9 were underground. Equipment includes a jaw crusher driven by a 9 h. p. gas engine. Bibl. : Cal. State Min. Bur., Report XIV, p. 2SS ; Chapter rep. bien. period, 1913-1914, p. 116; Bull. 27, p. 80. Manhattan Mine (Lake). R. B. Knox and Hugo D. Newhouse, owners, 819 Pacific Building, San Francisco. This group, formerly owned by the Lake Mining Company, includes the old Lake mine, and the Porphyry mine, and is in Sec. 1, T. 11 N., R. 5 W., and Sec. 36, T. 12 N., R. 5 W., M. D. M., 1 mile northwest of Knoxville and 20 miles southeast from Lower Lake. The nearest railroad point is Rumsey to the eastward. The total area is about 350 acres. The mine was first worked in 1862, the place being then known as Johntown. and the ore reduced in the furnaces of the Redington mine. It was idle from 1877 to 1884, from which time to 1905 it was again in the producing list. Some work was done in 1916, from which production resulted. The total recorded yield of the group has been 15,979 flasks of quicksilver. The mine and its geology have been described at considerable length ill i)revious reports, particularly by Becker- and by Forstner,"* the fol- lowing being quoted f )-om the latter : "The study of this mine is especially interesting in regard to the relation of igneous rock and the ore deposition. The ore deposits are found in a belt having a general northwestern direction, lying between l)asalt to the northeast and serpentine to the southwest. The basalt does not show at the surface in a continuous line : * * * The territory between the basalt and the serpentine is almost (>ntirel\- covered by tuff, except in * * * [;:;] places: * * * "The imdcrlying country rock is an altered Neocomian,^ crushed and altered into a material which is found through the entire mine in various conditions of hardness, * * * This material is locally called 'mudrock.' and is found also in other mines. * * * On contact of the mudrock and the basalt occurs a lireccia * * * 'See p. 217. post. =Becker, G. F., Geology of the (|uicksilver deposits of the Pacific Slope: U. S. Geol. Surv., Mon. XIIT. pi>. 2SL'. 4ti4. ISSS. ^Forstner, William. Quicksilver resources of California : Cal. State Min. Bur., Bull. 27, pp. Sl-89, IDO.-?. 'Becker, 021. cit., p. 464 I QUICKSILVER RESOURCES. 87 "Underground explorations liave proven that the sin-face indications in many instances do not represent underarround conditions. * * • One fact is, liowever, beyond doubt : Tlie eruptive actions are intimately connected with the ore deposition. Throug:h ttie serpentine runs a very prominent cropping of opaline material, near its northeastern boundary, wliich cropping is almost continuous to the Boston [Knox- ville] mine, where large ort> bodies have been found tlierein. A great amount of exploration worlv lias been done on tliese croppings without disclosing any ore, until recently a seam of fair ore. from 6 to 12 inches wide, has been discovered therein, about 400 feet soutlieast of tlie furnace. "All the territory between the basalt and the serpentine shows the action of mineral springs, which have formed large beds of sinter and other siliceous material. ****** 'The absence of ore deposits in the serpentine must be noted. * * * i\^q ore deposits are all contiguous to the basalt and do not extend to any distance from it, except in the St. Quentin deposit, where the cinnabar has been deposited from solfataric waters, which must have been related to the basalt. * * * Considering that the Boston and Manhattan deposits are only one mile interdistant, and that from tlie topograpliy it miglit be inferred that while not appearing at the surface, the vent tln-ough which the basalt extruded in the Manhattan persists toward the Boston, the entirely different nature of ore formation in these two lines is very notewortliy. "It is to be regretted that in no place in the Manhattan mine has the commercial development of the ore deposits caused the underground works to be run in a manner to determine the vent of the basalt extrusion, or whether on or near this vent deposits of greater persistence in depth would be found. The fact that every deposit as yet opened in this mine terminates in depth with the basalt, justifies the expectation that such persistence might be the case. "The irregular basalt occurrences found in the mine are probably intrusions, which follow pre-existing fissures, joints, bedding planes, or contacts, which would account for the lack of heat effect on the adjoining rocks by these igneous intrusives." There is occasionally a little pyrite, sulphur, and stibnite associated with the cinnabar. The maximum width of the ore body as worked was 100'. at the surface ; while the width was 6' at the 200' level. There are 3 series of fissures : N-S, E-W, and NW-SE, the dip aver- aging about 60°. There is no distinct foot wall. On Lake #4 claim, the hanging wall is sandstone. There is a shaft do^Mi 206', with levels at 106'. 156'. and 206'. Equipment includes: boiler and hoist; 20-ton Knox-Osborne coarse-ore furnace ; 24-ton Knox-Osborne fine-ore furnace : and a retort. Knox writes that : "This mine has been worked superficially only, and no definite ore system has been developed. The deposits, usually largest at the surface, diminished In size and value with depth and became improfltable at from 2.5' to 125' from the surface. "The outcrops were large and open pits twelve in number cover possibly four or five acres in aggregate area. "The cinnabar has evidently been deposited by springs resulting from regional volcanic activity. "Any revival of this property will demand considerable work, and a large amount of intelligence, if an extensive ore system is to be found beneath the basaltic surface. No attempt has been made to open at any depth." Bibl. : Cal. State :\1ix. Bur., Reports IV, p. 336 (table) ; V, p. 95: VI. Pt. I, p. 33; VIII, p. 412; XI, pp. 71, 72; XII, p. 363; XIII, p. 598 ; XIV, p. 288 ; Chapter rep. bien. period, 1913-1914, p. 116; Bull. 27, pp. 81-89. Geol. Surv. of Cm.., Geol. vol. I, p. 92 ; vol. II, pp. 126-128. :\Iin. Res. W. op Rocky Mts., 1867, p. 178 ; 1871, p. 15 ; 1874, p. 30 ; 1876, p. 20. U. S. G. S., Mon. XIII, pp. 282, 464; Min. Res., 1892, pp. 147, 160; 1902, p. 252; 1908. Pt. I, p. 686. Mountain Mine (also known locally as Simmons). 'SI. Johnson, owner, Yountville; E. E. Lillard, et al., lessees, Oakville. This pros- pect is in Sec. 2, T. 6 N., R. 5 W., M. D. M., west of Yountville and 88 CALIFORNIA STATE MINING BUREAU. south of the La Joya mine. A little work has been done spasmodically. The present lessees are planning to open it up. Bibl.: Cal. State Min. Bur., Reports X, p. 362; XIV. p. 291; Chapter rep. bien. period, 1913-1914, p. 119. Northern Light Prospect. Fr. Josh, owner, Lower Lake. It is about 2i miles west of Knoxville, and near the Lake County line. Idle. Bibl. : Cal. State Min. Bur., Report XIV, p. 289 ; Chapter rep. bien. period, 1913-1914, p. 117; Bull. 27, p. 92. Oat Hill Mine (Napa Consolidated). E. J. Sittig, 1216 Oxford Street, Berkeley, and R. P. Newcomb, 1052 E. 11th Street, Oakland, owners. E. J. Sittig and Earlbert Newcomb, Middletown, have leases on the dumps for concentration ; and Murray Innes, Kohl Building, San Francisco, has taken a lease on the underground portions of the mine. There are 17 claims in the group, all patented, lying at the Photo No. 16. Dumps of low grade ore at Oat Hill Quicksilver Mine, Napa County, from Eureka, Osceola and Humboldt veins. junction of Sees. 27, 28, 33 and 34, T. 10 N., R. 6 W.. :\r. D. M. (see Map, Plate V), between James and Bueksnorter creeks, and 9 miles southeast of Middletown. Elevation: 2250' (bar.) at the office. This mine was for many years one of the important quicksilver producers of California, having been opened up in 1876 and operated contin- uously up to 1909, when it was closed by the Napa Consolidated com- pany as being worked out — at least, the ore had dropped below a profitable working grade for tlie i)riee at which quicksilver was then f selling. The records show a total output of 152,066 flasks from 1876 to 1917 inclusive. The older worked ore shoots were on the Mercury and ^lanzanita veins, the later developments being to the southwest and around on the other side of the ridge, on tlie Escape, Eureka, Humboldt and Osceola veins. Though the ore w;is comiccted with the veins and on their foot- , QUICKSILVER RESOURCES. 89 Avail, there was little cinnal)ar in the siliceous vein matter itself. The values occurred almost entirely as impregnations in the soft, light-gray sandstone. The lenses of ore were all near to the surface, the deepest one on the Eureka reaching only a depth of 400 feet ; though the Man- zanita vein carried values down to the 750' level. In places, the stopes broke through to daylight. The largest single lenses were opened upon the Humboldt and Osceola veins, in both cases being stoped for a length of 500 feet. A flow of basalt is a prominent feature of the sur- face at Oat Hill. During the last two years that the Napa Consol- idated Company operated, the territory outside of the zone explored by underground operations was prospected by boring numerous holes to a depth of 200' to 350' from the surface, with a Davis-Calyx core drill. During their last year, no underground development was car- ried on, only the ore then in sight being extracted. It is estimated from the maps of the property that there are over 21 miles of under- ground workings in the mine. Equipment included two 50-ton Scott furnaces, which were dismantled and cleaned up when the mine was closed. Since 1913, during the seasons when water has been available, R. P. Xewcomb and succeeding lessees concentrated material from the extensive dumps on the property (see Photo No. 16). These oper- ations are described elsewhere herein^ under the section on metallurgy. Neweomb estimated that there are in excess of 250,000 tons of ore on the dumps w^hicli can be economically treated by this method, and that he could handle at a profit material carrying as low as 0.15% quick- silver (3 pounds per ton). Being a friable sandstone with impreg- nated cinnabar, and having lain out in the weather for some years, it is more or less disintegrated and air-slaked, requiring no crushing; so that it is particularly favorable for low-cost concentration treatment. Since the writer's last visit to Oat Hill, Murraj^ Innes, as lessee, has put on a number of men reopening certain of the old underground' workings and exploring for available orebodies that will pay to extract under present conditions. If developments justify it, his intention is to install furnace equipment. Wood costs $5 per cord. The present lessees on the dumps, Sittig & E. Neweomb, plan to carry classification of their table feed to a greater degree than has been done by any of their predecessors. On the trails and roadways about the Oat Hill ^See DD. 332-335, post. 90 CALIFORNIA STATE MINING BUREAU. miiK'. after a rain, cinnabar can l)e si-eu L-unceutraled aniun^- the rocks and small crevices of the water courses. Bibl. : Cat.. State Min. Bur., Keports V, p. 96; VIII, 413; X, p. 270; XI, pp. 65, 72; XII, p. 364; XIII, p. 598; XIV, pp. 289- 291; Chapter rep. bien. period, 1913-1914, pp. 117-119; Bull. 27, pp. 89-91. U. S. G. kS., Mon. XIII, pp. 354-358, 469; Min. Res., 1883, pp. 394-397; 1884, p. 492; 1888, p. 97; 1892, pp. 145, 160; 1902, p. 251; 1906, p. 497; 1907, Ft. I, p. 679; 1908, Pt. I, p. 686; 1909, Pt. I, p. 553; 1910, Pt. I, p. 698; 1911, Pt. I, p. 902. Eng. & I\IiN. Jour., Nov. 1, 1913. p. 828. Palisade Silver Mine (locally called Grigsby). R. F. Grigsby, owner, Calistoga. This silver mine is in Sec. 24, T. 9 N., R. 7 W., 3i miles northeast of Calistoga. It was first opened up in 1876, and was a bullion producer from 1888 to 1893. The vein mineral is quartz carry- ing antimonial silver sulphide, with which are associated cinnabar and pyrite. The ore was treated by dry crushing, roasting, and pan amal- gamation for its silver contents ; l)ut no attempts were made to recover the quicksilver present. Bibl. : Cal. State IMin. Bur., Reports V, p. 93 ; VI, Pt. I, p. 77 ; VIII, pp. 413-415 ; X, p. 363 ; XII, p. 376 ; XIII, p. 606 ; XIV, p. 270; Chapter rep. bien. period, 1913-1914, p. 98. U. S. G. S., Mon. XIII, p. 370 . Patten Claims (see also James Creek Placers). Mrs. M. F. Patten, owner, Calistoga. These consist of 600 acres of patented ground on James Creek, adjoining the Oat Hill group. So far, only the placer gravels in the stream bed has been worked; but there is stated to be cinnabar in i)lace in the sandstone on this property, which prospects are as yet undeveloped. Philadelphia Claims (James Creek prospect). This prospect is near (southeast from) the Oat Hill mine, l)ut has been abandoned since the death, about 1911, of the owner. Bil)l. : Cal. State Min. Bur., Report XIV, p. 291; Chapter rep. bien. period, 1913-1914, j). 119; Bull. 27, p. 93. Summit Mine. Joseph Scheerer, owner, 747 Noe Street, San Fran- cisco. It is in Sec. 19, T. 7 N., R 5 W., M. D. M., 3 miles west of Oak- ville and south of the La Joyd. It was a i)roducer in tlie early seven- ties, l)ut was idle for many years until quite recently. In 1916, some development work was done. Bibl.: Cal. State Min. Bur., Reports XIl, p. im'i; XIII, p. 599; XIV, I). 291 ; Chapter rep. bien. period, 1913-1914, p. 119; Bull. 27, p. 92. I\riN. Res. W. of Rocky Mts., 1874, p. 30. QUICKSILVER RESOURCES. 91 Twin Peaks Mine. B. A. & A. A. Wilson, and L. U. Pay, owners, Aetna Springs or Calistoga. This gronp of 5 claims near Oat Hill adjoins the Corona mine on the southeast, and is in Sec. 33, T. 10 N., R. 6 W.. and Sec. 4. T. 9 N., R. 6 W., M. D. M., about 9 miles north- east of Calistoga. In two years preceding 1906, it' is stated that a total of $40,000 in (|uieksilver was produced from a lens of ore. As the sur- plus is stated to have been all paid out in dividends and none used for further development, the mine was closed for lack of funds for devel- opment work, when the pocket had been mined out. Except for assessments-, the property remained idle until reopened in 1915 by the present owners, then under a lease. The mine is credited with a total output to the end of 1917 of 275 flasks. The footwall is sandstone and the hanging wall, serpentine. In 1916, a portion of the quicksilver yield was obtained by concentrating material from the dumps with a New Standard table. In September, 1917, they had 4 men at work. Some good ore had been struck on the 200-foot (upper adit) level; and a lower adit (400-foot level) was being driven to cut the vein with depth. Reduction equipment con- sists of 2 'D' retorts. Bibl. : Cal. State Mm. Bur., Report XIY, p. 291 ; Chapter rep. bien. period, 1913-1914, p. 119; Bull. 27, p. 92. U. S. G. S., Ann. Rep. XXI, Pt. VI, p. 278; Min. Res., 1902, p. 252; 1907, Pt. I. p. 679; 1911, Pt. I, p. 902; 1915, Pt. I, p. 269. Whitney Mine, G. B. Whitney, owner, Calistoga. This prospect is in Sec. 21, T. 10 N., R. 5 W., M. D. M., in Snell Valley, 10 miles south- east of ]\Iiddletown, on agricultural patented land. The property was not visited by the writer but we were shown specimens of the ore, which is a schistose sandstone impregnated with cinnabar. The coun- try rock is said to be sandstone and serpentine. Development consists mainly of a drift and winze, and several prospect holes. A few flasks of quicksilver have been produced, with a retort. The owner states that lack of capital has prevented more extensive development. Bibl.: Cal. State Min. Bur., Report XIV, p. 292; Chapter rep. bien. period, 1913-1914, p. 120. 92 CALIFORNIA STATE MINING BUREAU. NEVADA COUNTY. The reported occurrence has been noted by Lindgren/ of gold amalgam in the Odin drift mine, and of cinnabar in the Manzanita hydraulic mine, near Nevada City. Apparently neither had been definitely identified in place in the quartz veins themselves, though not unlikely, as such occurrences have been found elsewhere in the Sierran 'Gold Belt.' The same author, with Turner- describes an occurrence, in place, a short distance south of the above area in this same county : "One of the few occurrences of cinnabar in tlie Sierra Nevada is found near Nicker- son's ranch in the soutlieastern corner of tlic Smartsville area [12 mi. south of Grass Valley]. The ore occurs sparingly scattered tlirough a quartzose and dolomitic gangiie on the contact of serpentine and quartzite." Bibl. : Cal. State ]Min. Bur., Bull. 67, p. 35. Report State Bd. OF Agr., Annotated Cat. of iMineral species in Cal., 1866. U. S. G. S., Ann. Rep. 17. Pt. II. pp. 116. 119; Smartsville Folio (No. 18). p. 4. ORANGE COUNTY. The occurrence of native mercury associated with small veins of barite has been recorded, 2 miles east of Tustin, in an outlying hill of Tertiary sandstone, partly surrounded by the Santa Ana plain. There has been no commercial development. Bibl.: Cx\L. State :\Iin. Bur., Reports XI. p. 118; XV, p. 516; Chapter rep. bien. period, 1915-1916, p. 56; Bull. 67. p. 35. ^Lindgren, Waldemar, The gold-ciuartz veins of Nevada City and Grass Valley dis- tricts, California: U. S. Geol. Surv., Ann. Kept. 17. Part II, pp. 116, 119. 1896. =L,indgren, W., and Turner, H. W., Geologic Atlas of U. S. : U. S. Geol. Surv., Smartsville Folio (No. IS), p. 4, 1S95. QUICKSILVER RESOURCES. 93 SAN BENITO COUNTY. San Benito County ranks aniouo- the oldest and most important quicksilver producing counties in California. It contains the New Idria mine, which stands second only to the New Almaden mine, both in length of continuous operations and in point of total production to date. In fact, since the decline of the latter mine from its former importance, the New Idria for some years past has been the largest single producer of quicksilver in the state. The total recorded output of the quicksilver mines of San Benito County is shown by the accompanying tabulation : Q uicksilver Production of San Benito County. Tear Flasks Value Year Flasks Value 1865 *17,455 6,525 11,493 12,180 10,315 9,888 8,180 8.171 7,735 6,911 8,432 7,272 t2,000 6,316 5.138 4,425 3,209 2,775 1,953 1,606 1,025 1,144 1,406 1,890 1.320 980 977 792 $943,617 346.673 527,529 559,062 473.459 567.373 516,158 538.714 621,353 726,899 709,553 319,968 139,000 2.35,587 169,040 1.32,048 99,479 82.778 55,123 46,173 .31,263 35,178 49.913 80,088 56,100 44,100 51,293 35,838 1892 848 869 1.005 1,100 1.335 3.605 5,000 4.780 3.990 4.80O 7.291 8,180 ±8.480 7,764 7.203 7,675 9,600 8,900 10.800 9,775 9,743 9,719 6,633 6,291 11,110 11,150 $34,523 1866 _- 1893 31.936 1867 1894 30,861 1868 1869 1870 1895 1896 1897 36,000 46,725 135.185 1871 1898 - 190.000 1872 1899 - -- 245.000 1873 1900. - - - 180,000 1874 1875 - 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 242.300 300,081 1876 - _. 344,251 1877--. - - 314.000 279,651 1878 262,909 1879 -- 292,878 1880 1881 1882 1883 1884 188.5 1886 1887 1888 - 405,792 440,241 488.700 449.748 409,596 390.995 325,349 475.370 1,032.156 1889 1890 1891 1917 Totals 1,057,770 316,159 $16,641,376 *Production of Xew Idria Mine from IS^oS-lseO: yearly details not obtainable. tEstimated output of Cerro Bonito, Monterey and Stayton mines, 1870-1877; yearly details concealed under heading of "Various Mines" in early reports. JFlasks of 75 pounds since June, 1904: of 7&1 pounds previously. There are three quicksilver districts in the couut.y, all situated in the Diablo Range, which traverses the eastern part of the county in a northwest-southeast direction. The Stayton district is at the northern end at the junction of San Benito, Santa Clara and Merced counties. The New Idria district is in the southea.st corner of San Benito County; and the third district, in which are the old Cerro Bonito and Bradford mines is situated between the other two. Only the New Idria district has been active recently, or has ever produced quick- silver to any notable extent, the others having been idle for many years. 94 CALIFORNIA STATE MINING BUREAU. NEW IDRIA DISTRICT. The general geology of this region, with particular reference to the quicksilver deposits, has been described in considerable detail by- Becker^ and Forstner.- The nio.st recent geological map of this part of California is that accompanying the report of Anderson and Pack'' on the oil possibilities of the region and from which we have prepared the map presented herewitli (Plate Xll). with some minor ndditions from our own observations. Photo No. 17. Serpentine surface near New Idria, San Benito County, showing characteristic sparseness of timber and brush growth. The most striking feature of the geology of this district is the large area of serpentine to the south and southeastward from New Idria. Many of the ridges and slopes within this area are characterized by the scarcity of underbrush and the sparseness of the timber growth (see Plioto 17). In such phiccs the serpentine is light colored, pale blue and green, and pulverulent. In other portions of this .serpentine area where the reddish eoloi- of the soil indicates the presence of iron, tlie underbru.sh is fairly abundant. This is paiiicularly the case on 'Beckor. G. F., OeoloKV of tlio quicksilver deposit.-? of the Pacific Slope: U. S. Geol. Survey., Mon. XTII. pp. fi4. 1S9. ^2^:K 2in-.''.n!). 4f)r>-4fi7. ISSS. =Forstner, Willi.im, Quicksilver resources of California: Cal. State Min. Bur., Bull. 27. pp. 12.">-12tt. 1!tn3. "Ander.son, R.. & Pack. R. W.. Geolosy and oil resources of the west border of the ."^an .loariuin Vallev north of Coalinga, California : U. S. Geol. Surv.. Bull. 603, pp. 206. rt scq., 191, "5. PLATE XII. GEOLOGIC MAP OF NEW IDRIA DISTRICT SAN BENITO CO.. CAL. Sca/e of miles. (Affer i/SGS. with addifions by the aufhors.) LEGEND Tej TV Efchego/n ^-v Jacalitos Vaqueros Tk Kreyenha- ^^ gen sna/e I Martinez Moreno Ttj Tejon Tmc J Cantua %^^J> Panache sandstone.) w^jjI^ Franciscan Serpentine 1916 QUICKSILVER RESOURCES. 95 the westt-ni slope of Sampson Peak where the magnesite deposits are being worked. In the gravels of many of the stream beds in this area, chromite float and sands are noticeable. Some commercial shipments have been made of such ehromite float gathered together; but thus far no bodies of workable size in place have been reported. Most of the smaller quicksilver properties in the New Idria district are within this serpentine area. The Aurora mine, a mile south of the New Idria mine, is just within tlie boundary of the serpentine, being not over ^ mile from the contact. In contact with the serpentine along its northern edge, is a tongue of Franciscan shale and sandstone, this being covered to the north and east l>y the overlying Panoche formation, a member of the Chico group of the Upper Cretaceous. This latter formation is covered to the north by succeeding later Cretaceous, Eocene and other Tertiary sedi- mentaries in turn. The ore bodies of both the New Idria and San Carlos mines, the most important in the district, occur in the altered and highly fractured shale and sandstone of the Franciscan formation near its contact with the overlying Panoche formation. The principal source of the ore in the New Idria mine is the stockworks deposits, where the cinnabar acts as a cementing material binding together the brecciated Franciscan rocks. Cinnabar also occurs here disseminated in the more porous sandstone, as thin films coating fracture surfaces, and as fillings in true fissure veins. The metal now obtained is entirely from cinnabar, but in a portion of the earlier, upper workings a considerable deposit of metacinnabarite was taken out. The railroad outlets for the district are: via Mendota, 40-45 miles to the northeastward, and via Tres Pinos about 55 miles to the north- west. For the mines at the southern end of the district, near Hernan- dez, the rail outlet is via either Coalinga or Kings City, each about 40 miles distant by the roads. Round timber for mining is obtainable in the district by contract with the U. S. Forest Service, but not abund- ant. The New Idria Company for many years used local, round tim- bers, but is now hauling in sawed timbers by motor trucks from Tres Pinos. That company also, uses oil for fuel, which is brought in via ^lendota. CENTRAL SAN BENITO DISTRICT. The central San Benito district is not a well-defined district as are the other two, but includes a few scattered mines between the New Idria and Stayton areas. The principal mines are the Cerro Bonito and Bradford which yielded some quicksilver in the 70 's, but have had little work done on them since. They arc in the Diablo Range, which here consists mainly of rocks of the Franciscan series, in places cov- 96 CALIFORNIA STATE MINING BUREAU. crcd l\v or adjaeent to yoniiajer formations. The countrj^ is fairly well t iiiiluTcd, holli I'oi' iiiiiiiiiu' ;ind fuel purposes; and the rail outlet is via Tres Pinos. STAYTON DISTRICT. The Stayton district is mainly in San Benito County, but in part extends over Ihc l)oundary lines into Santa Clara County on the north and into Merced County on the east (see Map, Plate XIII). The mines in this district have been mostly idle for many years, and were not visited by the writer, the following description being quoted from Forstner's^ report: "The surface rock of this district is prominently of igneous origin and except in tlie northwestern pait the underlying sedimentaries are almost exclusively found in the bottoms of the deeply-eroded gulches. The post-Tertiary igneous rocks vary greatly in cliaracter ; from very fine-grained, dark-colored basic, basaltic rocks, to very fine-grained, nearly white acidic rocks. The great majority is, however, a light grayish-colored porphyritic rock, which Whitney classed as trachyte, but which closely answers the asperites described by Becker. There is no doubt that this district has been the locus of repeated igneous eruptions, and that these different igneous rocks represent various stages of magmatic differentiation. "The sedimentary rocks belong to the metamorphic series, prominently sandstones. * * * Some shales are also exposed, * * * Only at one place in the northwest corner of the district, in the old Comstock property, is an exposure of serpentine noted, and this not over 1000 feet wide, abutting to the west against schist and to the east against a flow of basalt. "There are no hot springs in the district, but in the western belt, sulphur emana- tions principall.v carrying antimonious ores, are very prominent, and the ledge matter and part of the wall rocks in all the metalliferous deposits have been so thorouglily leached by sulphurous waters that determination of tlieir original com- position is extremely difficult, if not impossible." The district is 15 miles from the railroad at Hollister. The vicinity is practically devoid of mining timber, but there is ample wood for fuel. The following claims correspond to the numbers appearing on the map of the district: 1. Santa Cruz; 2. Mariposa; 3. Green Val- ley; 4. F. Smith; 5. Cold Springs; 6. McLeod; 7. Badger; 8. Fair- play; 9. Santa Clara; 10. Pacific; 11. Last Chance; 12. North Star; 13. Stayton. Alpine Quicksilver Mining Company (one lime called the Esmer- alda Quicksilver Mining- Company). H. B. Leonard, manager, San Benito; D. McPhail, Hollister. Cal., secretary. The company owns 32 full claims in Sees. 13 and 14, T. 18 S., R. 11 E., 6 miles from Hernan- dez and 40 miles from Coalinga, the nearest railroad point. These claims occupy the southwestern portion of the zone of highly metamorphosed silicified serpentine which extends from the creek just east of Los Picachos Peak, to the old Clear Creek and Boston mines in Sec. 2, T. 18 S., R. 11 E., M. D. M. They have a total length of about 1^ miles along the strike of the outcrop zone and join the INIouterey Group on the northeast. The original discovery was made by Sil- vester Tirado, who sold the early holdings to the present company about 1910. They have since made additional locations. The surface outcrop is . ochreous and hinhlv silicified. but as one descends into the mine the 'Op. cit., pp. i:?)-].-?!. PLATE XIII. Geological Map of Stayton District. Reprinted from I'.ulletin No. 27. 38:>10 p. 96 QUICKSILVER REtSOL'KCES. \J i serpentine shows less and less alteration. A slip at the discovery point strikes S. 20° E.. with a dip of 70- NE. Ore so far mined has been taken out in bunches alonii' the loeus of this slip for an inclined depth of 190 feet, alonii" wliich the sliekensided wall can be easily traced. The width of ore at the outcrop was about two feet. No sur- face work has been done to determine the extent of mineralization along the strike. The older work was carried on through a tunnel 150 feet long- from which an inclined raise at an angle of about 45° fol- lowed the mineralized fault zone 100 feet to the upper tunnel, which was only a few feet long. Small stopes along the raise yielded some good ore wliich was treated in 'D' retorts and pipe retorts, giving a nominal output. A small stope was also driven ofit: the lower tunnel and a 15-foot drift from the raise between the levels, but the latter did not uncover ore. Later woi-k has gone on through a new tunnel, which had been connected with the next level above by an inclined raise of 90 feet and which is 230 feet on the incline below the outcrop. In December. 1915. this had been driven 800 feet in an endeavor to cut the 'vein' at depth, but Avas in serpentine the entire distance. This showed minor fractures filled with silica and calcite, but only small traces of cinnabar. Two crosscuts, driven 45 and 75 feet respectively, off this level, failed to sliow^ ore. Work had started on a stope four sets wide off the middle level (the old lower tunnel). This had entered a mineralized lens and had been carried 15 feet without having passed out of ore. The cinnabar made in a chaleedonic gangue varying in color from light to black, and also in the fractured serpentine with a gangue of silica and calcite, in narrow stringers. Hand specimens show bunches of grey and greenish chalcedony carrying cinnabar, asso- ciated with lumps of magnesite, through which tiny specks of cinnabar are sprinkled. Considerable native mercury in serpentine was also noted in this stope. This ore was of furnace grade, and in spots rich enough to retort. The reduction plant formerly used, and still in order, consists of 8 'D' retorts and 2 pipe retorts, with 6 other pipe retorts which had been burnt by using too hot a fire. The new plant, which was com- pleted early in 1916 includes an improved Scott furnace of 20 tons capacity, and four brick condensers. The bricks w^ere burned at a clay bed on the stream four miles from the mine, and heavy Avork was encountered in hauling them to the furnace site. This plant was oper- ated for several months up to November, 1916. since which it has been closed down, except for a few weeks in the summer of 1917. The total recorded output of the Alpine mine has been 408 flasks to the end of 1917. 7— 3.S540 98 CALIFORNIA STATE MINING BUREAU. This district is handicapped by having roads which become nearly impassable after a rain, and mining development is bonnd to be retarded by the difficulty and cost of transportation. The furnace is located at an elevation of 3GU0 feet (U. S. G. S.). The country is entirely serpentine, with the characteristic sparse growth of brush and only scattered pine timber. The company obtains timber from its own land, and pine wood for fuel cut near])y at a cost of .$8 to $9 per cord, delivered. A few men are at work on development, and report a new shoot of ore encountered, which promises well. Bibl. : Cal. State Min. Bur., Keport XV, pp. 649-651 ; Chapter rep. bien. period, 1915-1916, pp. 55-57. Andy Johnson and Fourth of July Mines (Flint Group). Thomas Flint, owner, Jlollister; 0. A. Austin, et al., lessees, fll85 Busch Ave., Hanchett Park, San Jose. This group comprises the old mines known as the Andy Johnson, Fourth of July, and Clear Creek, and consists of 552 acres of patented land in Sees. 2, 11, 12 and 13, T. 18 S., R. 11 E., and Sec. 18, T. 18 S., R. 12 E., M. D. M. The Clear Creek, and Andy Johnson (and the adjacent IMonterey Group of the Esmeralda company) occupy the northwestern portion of the prominent zone of ochreous, silicified croppings which strike northwest from the Hernan- dez (Los Picaclies) mine. They lie adjacent to Clear Creek, taking in the hills to an elevation of about 3700 feet (barometric reading) and 600 feet above the creek. The Andy Johnson claim adjoins the recently located Capitola on the southeast, where some very rich sur- face ore is being retorted. These properties have been idle so long that definite data concerning them is not obtainable. The Andy John- son, according to INIr. Flint, was worked by an open cut and was noted for the amount of native mercury yielded, as much as a pint being taken at times from one spot. The Clear Creek mine was oper- ated through a tunnel 600 feet long, from which underground oper- ations on rather an extensive scale revealed good ore. All these work- ings caved in years ago. A furnace for I'educing the ore was oper- ated on the bank of Clear Creek near the junction of the Alpine and New Idria roads, but this also has long since fallen to ruin, and defin- ite information concerning the output of mercury fi-om it is not to !)e had. The mines were closed in tlie early eighties Avhen the price ol' quicksilver was so low as to practically prohibit mining. It is believed that workal)le ore remains in these properties. Most of the ground has not been thoroughly explored, and in view of the showings of ore in other near-by mines on the same series of out-eroppings, it aj^pears as though thorough prospecting would hr justified on these lioldings. Values of $1.50 to .$2 per ton, in gohl, are reported from assays of QUICKSITA'ER RKSOURCES. 99 samples of the ore. The country is mantled by serpentine in deeply disintegrated and rounded knolls, carrying- little vegetation except along the watercourses. A fairly good road reaches the mines from Hernandez. 5 miles distant. In 1916, the lessees built a Johnson-^NIcKay retort, and made a few flasks of quicksilver. They did some exploratory work and reopened portions of both the Andy Johnson and the Fourth of July mines, up to November, 1917, some ore being taken out and retorted. At present idle. Bibl. : Cal. State ]\Iin. Bur., Report XY, p. 654; Chapter rep. bien. period, 1915-1916, p. 60; Bull. 27, pp. 131, 137, 138. U. S. G. S., Mon. XIII, p. 309. Geoi.. Surv. of Cal., Geol. vol. II. p. 123. Aurora Group (one time called Morning Star Mine), and Monterey Group (one time called Boston), owned by the Esmeralda Quicksilver ^Mining Co., Richard Phelan, president; R. W. Gilloghy, secretary; II. T. Hays, engineer; office, 942 Phelan Bldg., San Francisco, Cal. The two groups consist of a total of 38 claims, the Aurora being in Sec. 5, T. 18 S.. R. 12 E., M. D. M., and the IMonterey Group mainly in Sec. 12, but extending into Sees. 11. 13 and 14, T. 18 S., R. 11 E., 5 miles southeast of Idria, and just north of the Alpine mine. Both groups are within the serpentine area. Only a small amount of devel- opment work has been done on the ^Monterey, which it is stated wnll be .equipped and worked in conjunction with the Aurora. In the latter the principal development is an adit, in between 300' and 400' and a raise connecting with the surface, where there are several open cuts. The cinnabar occurs in a vein-tilling of chalcedonic silica dark green to white in color. The croppings have a course of S. 15° E. Though said to have been discovered in 1853, it has been worked only at irregular intervals. In 1911 a revolving furnace, similar to a cement kiln (see Photo X0..I8), was installed, but owing to mechanical difficulties it was operated only one day. The flue connections leading to the condensers can be seen at the upper end. In October, 1915, the furnace was repaired and refitted, and operated for a few weeks, until severe win- ter storms damaged the roads from ]Mendota, cutting off the supply of fuel oil. Operations have not since been resumed except for a short period of prospecting work in the open-cuts in July, 1917. The capac- ity is stated to be 50 tons per day. According to J. H. Eggers,^ who superintended the work at that time, the ore was crushed to ^ inch, ai.d passed througli the furnace in 9 minutes. This he considers too 'Personal conversation with the autlior. lUO CALIFOUNIA STATE MINIX(; BIHKAU short a time, as tlie furnace should he lonjior and set on a flatter pitcl). During these latest operations, ore was quarried from the outcrop. Bibl. : Cal. State Min. Bur., Report XV. p. 652 ; Chapter rep. bien. period. 1015-1916, pp. 57-58; Bull. 27, p. 131. Min. Res. W. OF Rocky Wrs., 1874. p. 381. U. S. G. S., :\ron. XIII, pp. 309, 466; ]\Iin. Res. 1914. Pt. T. ]). 326; 1915. Pt. I. p. 269. Geol. Surv. op Cal., Geol. vol. 11. p. 12(». ■«!V 'Mikf Photo No. 18. Rotary furnace, Aurora Mine, San Benito County. Benta Group, in Sees. 20 and 29, T. 18 S., R. 12 E., M. D. M., was located in 1913 hy IM. G. Ramirez and S. Tirado. of Hernandez. There are two claims in the group, which joiii.s the Ramirez or Los Picachos claims on the southwest. The claims are on the same series of highly siliceous cropping.s which sh(»\v so prominently on the Ramirez prop- erty, lint the serpent iiie appears less silicilied. Only the annual assess- ment work has been done so far. A little cinnabar has been found, occurring in veinlets with silica in the serpentine fractures. It is in the Monterey National Foi-est. reached only by tJ-ail. P.ibl.: Cal. Statk .Mix. P»i'k.. Reitoi't XV. p. (i52; Chapter rep. i)ien. |)ei'i(i(i. 1915-1!)1(), p. 58. Bonanza Group. P>onanza Quicksilver ]\Iining Co., owner; S. H. Bauman, president, llernaiulez. ^1. G. Ramirez and Ramon Tirado, QUICKSIIA'KR RESOURCES. 101 of Hernandc/., m.-ulc locations here on two claims, naiiiinii' lliciii 1he Jk)iianza 1 and 2 in tlic winter oC lill-'x There is no variation in geolo.ii'y from the other ])roperties near-by, except that these claims are a little away from the line of croppings and exhibit a less highly siliciHed serpentine. They lie just southwest of the Benta claims, in Sec. 29, T. 18 S., R. 12 E., in the IMonterey National Forest and are accessible only by trail, a distance of 2.] miles from the Florence Mack, o)- T) miles southeast of the Alpine mine. An adit has been driven in about 60 feet, and is reported to have crosscut a promising looking body of ore. A few men are at present employed on development work. Bibl. : Cal. State Min. Bur., Report XV, p. 653 ; Chapter rep. bien. period, 1915-1916, p. 59. Bradford Mine (Cerro Gordo). J. F. Tatham, lessee, Almaden Road, Los Gatos. It is in Sees. 3, 4, and 9, T. 15 S., R. 8 E., M. D. M.. on Tres Pines Creek about 5 miles each of Emmett; and 18 miles from Tres Pinos. Cinnabar was discovered here in 1859 as an incident to the construction of a road from Tres Pinos to the New Idria mines; and for a inimber of years various prospecting and development work was done. It is at the contact of a belt of sandstone on the west, and serpentine to the east, both having a northwesterly strike. The west- ern part of the serpentine consists of a highly silicified belt of varying width, in part opaline rock, carrying some cinnabar. Between this belt and the sandstone is a wide belt of black gouge, and at least one other belt of black gouge has been found in tunnel No. 2 in the silici- fied serpentine. An incline shaft, following the contact of the opalized serpentine with the underlying gouge, was sunk 200 feet. At 160 feet vertically below the collar of the shaft, a tunnel was driven in 535 feet, and connected by a raise to the shaft. No defined orebod.y was found, but the serpentine is stated to carry some cinnabar throughout. The surrounding country is well timbered. There has been no production in recent years. Bibl.: Cal. State Min. Bur., Report XV, p. 653; Chapter rep bien. period, 1915-1916. p. 59; Bull. 27, pp. 131-133. Butts Mine. Wm. Butts, owner, Pine Rock, via Tres Pinos; Geo. Kline, lessee, Pine Rock. Located in Sec. 4, T. 16 S., R. 8 E., M. D. ^[., 21 miles south of Tres Pinos. The old workings of this mine, wliicli have been abandoned for years, produced only a small amount of mercury. The new workings, which have recently yielded some metal are located about -| mile north of the old mine. An open cut and tunnel totalling 75 feet, driven some time ago l)v Kline, in wliieli 102 CALIFORNIA STATE MINING BlREAir. it is reported tlial liooil ore \v;i.s fouiid. have caved in. A tiimn'l atul ()]n'n (111 totaling 60 feet have been driven above this caved ground and al)()iit 20 f(M't lidow the oiilci-oi). Tliis lias ciil dia'^onally across a chert and sandstone breccia which carries ore for a width of about 18 inches. Cinnabar and metacinnabarite occur in the cementing material of the breccia witli a calcite gangue. The work done is not sufficient to show conclusively that the deposit is in place and there is only one outcrop of the cinnabar-bearing breccia, but the strike of N, 35° W., and dip of about 60° NE. (as closely as they can be measured in the shallow workings) agree with the general run of the country rocks and appear to confirm the supposition that the deposit is in place and not fragmental. The claim is at an elevation of about 2300 feet, with sandstone and shale country rock and metamorphics derived from these sediments. Reduction is carried on in a 'D' retort. Two men are occasionally employed. In December, 1915, one man produced a flask of mercury in 19 days, working alone and carrying the ore on his back some dis- tance to the retort. Wood for fuel is available, but there is little min- ing timber near-by. Bibl. : Cal. State Min. Bur., Report XV, p. 653 ; Chapter rep. bien. period, 1915-1916. p. 59 ; Bull. 27, p. 133. Cannon Mine. A. C. Cannon, formerly owner, Emmett. It is in Sec. 4, T. 15 S., R. 8 E., M. D. M., north of and adjacent to the Brad- ford mine, being on the same line of croppings. Some development work was done years ago. but nothing recently. The, serpentine car- ries cinnal)ar, but no shoot of payable ore was found. Bibl.: Cal. State Min. Bur., Report XY, p. 6'A: Chapter rep. bien. period, 1915-1916. p. 60; Bull. 27, p. 133. Cerro Benito Mine. Cerro Bonito Quicksilver Mining Company, owner; Thos. Flint, president, Hollister; N. C. Briggs, secretary. It is in Sec. 31, T. 15 S., R. 10 E., M. D. M.. 30 miles southeast of Tres Pinos and two miles south of Llanada. It was one of the early mines opened in the county. Patented. A Knox and Osborne furnace w^as in operation here previous to 1874. and production up to 1876 is said to have been about 800 flasks. The mine showed little activity after that until about 1902, when some work rebuilding the furnace and reopening the tunnel was done; but no production since then has been reported. The geology of the vicinity is complicated. Between the property and Panoche Valley is a flow of basalt. The top of Cerro Bonito liill, which rises steeply, is surrounded by two lines of blufl's. one forming the top itself, the other from 200' to 300' lower and mucli more prominent, especially on the north and northwest sides, where in QUICKSILVER RESOURCES. 103 places the bluffs are 100 feet hioli. Tliese bluffs are of a hard siliceous material, probably a nietamorphic breccia recemented by silicificatiou. Some black opaline rock is found through this formation, and occa- sionally some sandstone. In three places the breccia overlies the regu- larly-bedded sandstone. The mine was developed by a large amount of surface work and rather extensive underground workings, which are now mostly inaccessible. The geology was described in some detail by Forstner^ who states that the ore bodies in the two upper series of workings in the breccia, were never connected with those in the under- ground works of the main, or 'sandstone' tunnel, and appear to be a separate deposit. "From the fact that in the sandstone tunnel cinnabar is found in the sandstone, it must be conchided that the ore deposition took place through water channels cutting: through this sandstone ; but the occurrence of the recemented breccia so extensi\ely overlying unaltered and undisturbed sandstone is as yet unexplained. Tlie large bodies of blaclv gouge (attrition products), showing very important move- ments in the strata resting upon tlaese same sandstone beds, render the explanation all the more difficult. It is hardly conceivable that all this metamorphic material lias been moved into its present position by dynamic action finding its center in Cerro Bonito Hill. * * * The cinnabar forms generally in the hard, siliceous bi-occiated material, which may be considered the gangue rock.'" Timber for both mining and fuel purposes is available near-by. Bibl. : C-VL. State Min. Bur., Report XV, p. 651 ; Chapter rep. bieu. period, 1915-1916, p. 60; Bull. 27, pp. 131-137. Min. Res. W. of Rocky Mts., 1875, p. 14. Don Juan and Don Miguel Mines (also known as San Benito, and Cody). AV. A. Breen, manager, Hernandez. This group in Sec. 36, T. 18 S.. R. 11 E., and Sec. 31, T. 18 S., R. 12 E., M. D. M., on the San Benito River southwest of Picacho Peak has been idle for many years. It is stated that a company has recently been formed, and 8 men are now at work, reopening and retimbering the old tunnel. It is proposed to build a small furnace the coming spring (1918). Bibl.: Cal. State Mix. Bur., Report XY, p. 651; Chapter rep. bien. period, 1915-1916, p. 60 ; Bull. 27, p. 137. Florence Mack Mine. C. P. Smith, owner. King City. In 1915-1916 it was leased to G. AV. AVarner and S. M. Suffron, Paso Robles, but is at present idle. The holdings consist of 6 full claims, with a total length of 6000 feet, in Sec. 32, T. 18 S., R. 12 E., M. D. M., on Saw Mill Creek. 7 miles from Hernandez and 30 miles from Coalinga, about 'Op. cit., pp. 134-137. 104 CALIFORNIA STATE MINING BUREAU. Photo No. 19. Old and new prospect tunnels. Florence Mack Mine. The old (upper) tunnel was a few feet too high and failed to uncover the vein; the lower tunnel showed a fair prospect of cinnabar. Photo by C. A. Logan. one mile from the main liishway joining" Ilollister and tlic latter. According to Logan^ : "The development of the propert>' was done largely liy a Mr. Courtney, of Hanford, who prospected it under bond in l!t04 and the following years. The mineralized zone strikes northwest and (lii)S 40" to 4.5" SW. The tunnels and crosscuts show a stratimi of black clay shale or 'mudiock' about two feet wide, carrying cinnabar values near the footwall, which is a fine-grained indurated sandstone or shalt>. This belt is cut by numerous p.N'rite stringers, carrying considerable cinnabar. There are three tunnels on each side of the creek, but the work was done mostly on the left or northwest side. "The lower and chief tunnel on this side enters the hill alnmst east and west. Near the portal the first crosscut north about 40 feet shows no ore. About '^0 feet from the portal this tunnel branches, the chief working running N. 20° "W. A crosscut 12.'J feet long east and west shows stringers of small size, striking noi'th and south and carry- ing ciniKiliar. One hundn^d feet from tlic portal a crosscut l.'i feet long was driven to follow a highly pyiitized zone one foot wide striking northwest. r>i'ite stringers about 2" wide, nearly solid, occur here, giving out, however, at a length of C to S'. They carr.v good fiuantities of cinnabar. l>\air ore in the vein was struck in this tunnel at a distance of 154 feet, and was followed to a shaft, 50 feet farther. This 'Logan, C. A., Bradley, W. W.. et al., Cal. State Min. r?ur.. Rep. 1'.)ir, 1!il(;, p. Mineral resources of Montere>-, CI, 1017. et al counties QUICKSILVER RESOURCES. 105 slial't ami the tunnel, at a distance of 50 feet beyond the shaft, were inaccessible and efHoresccnces cm the tunnel sides obscured observation. "The second tunnel runs N. 20° E., 100 feet. It shows mudrock, 2 feet wide, carry- insi' cinnal)ar near the footwall. A crosscut 20 feet southwest follows F'eS- stringers l"'wide carrvins cinnabar. The main crosscut runs 120 feet NW.-SB. and at its end is a small hole cut down on the vein; a 20' branch crosscut connects with the raise from tile lower tunnel. 60 feet below. "The upper t\umel is 40 feet above the second and 50 yards west. It is a crosscut tunnel, exposing at the breast the same 2' stratum of black clay shale, but no cinna- bar is in evidence. "There is a large tonnage of low-grade ore on the dump at this mme, which has lieen lying for some time and should prove susceptible to concentration. A considerable portion of it would make furnace ore. '' * * The sedimentary country rocks and tlie nature of the vein filling distinguish the mine fi'om those 2 miles or more north. It is comjiletelv outside the serpentine belt. The old tunnels south of the creek were sliort and appear to have been driven too high. The vein crosses the creek and has Iieen exposed on the southeast side bv a short tunnel driven in 1915 ; one of the old tunnels, driven in 1906 scarcely 10 feet above and to the left of the new opening, failed completely to uncover ore." (See Photo No. 19.) In December. 1915, a 12-pipe retort plant, with a daily capacity of 250 lbs. of ore per pipe, was built. It was observed that no water had been provided to cool the exit pipes, and the fire seemed to be too hot for o'ood recovery. The ore is highly pyritiferons and so requires great care to avoid roasting at too high a temperature. Bilil. : Cal. State j\Im. Bur., Report XV, pp. 655-657 ; Chapter rep. bien. period, 1915-1916, pp. 61-63. French Ranch, H. French, owner, Hollister. This now embraces Hie old properties formerly known as the Santa Cruz and Mariposa mines, of the Stayton district, in Sees. 20, 21, 28 and 29, T. 11 S., R. 7 E., M. D. M. Some surface indications of cinnabar here caused prospecting in the seventies, but a little work revealed the fact that the cinnabar did not persist, and stibnite was found to be the principal mineral. Bibl.: Cal. State Min. Bur., Reports XII, p. 365; XV, p. 657; Chapter rep. bien. period, 1915-1916, p. 63 ; Bull. 27, p. 147. Hernandez Quicksilver Mining Company (knoAvn also as Picachos or Los Picachos Mine, and the Ramirez Consolidated). ^I. G. Ra- mirez, president, San Juan Bautista; A. E. Reynolds, secretary. King City ; Silvester Tirado, superintendent, Hernandez. Six claims, 5 of which are patented, form the group. They lie in Sees. 19 and 20, T. 18 S., R. 12 E., M. D. M., and are accessible only by trail, being 5 miles from the Alpine mine and 2 miles north of the Florence IMack mine. The elevation is 4500 feet (U. S. (1. S.). Through this property, strik- ing northwest and extending to the northern end of the Flint group, 5 miles distant, is a wide and prominent mineralized zone, revealed on the surface by deeply altered, bold, siliceous outcroppings, stained a rusty color by the iron oxide present. The softer parts of this rock have been weathered out, leaving an altered material composed prin- cipally now of silica, showing in different places a great number of phases — chalcedony, quartz, flint, and agate. At the Hernandez this ]0G CALIFORNIA STATE MINING BUREAU. zone of croppings is nearly ^ mile wide, ending abruptly about 1500 feet southeast of the furnace. The mine was opened in the days of the old quicksilver boom by a tunnel driven northward from the southern slope a distance of 3000 feet, designed to cut the ore exposed in the outcrop at depth. As far as can be learned, this work never led to any appreciable production. In later years operations have been confined to the exploration of the outcrop near the surface in the southeastern part of the holdings, although there are other prospects of cinnabar in the mile of outcrops Photo No. 20. Characteristic outcrops; Los Picachos Peak, Hernandez Quicksilver Mine, San Benito County, California. embraced in the claims, which would seem to warrant prospecting. The present company has been in possession since 1904, but work has been desultory and actual progress in development small. For about four years up to 1916, a small yearly production of metal was made in a retort of four pipes. The ore has come from the southern and eastern sides of the outcrop near the surface. Inclined shafts, one of 160 feet and two of 50 feet each, have been driven, besides which some rich ore has been taken from the face of the oiilcrop. The bluffs a1 llic riiniaee face southwest and stand up about 100 feet above the furnace, showing cinnabar in iiiaiiy plates (see Photo No. 20). The ore being treated in QUICKSILVER RESOURCES. 107 December, IDl."). came partly from an itu-line about 45 feet deep. This had been sunk on a knis of ore wliicli hatl a thickness of about 3 feet, width of 40 feet and had been worked out 50 feet along the strike. The shoot strikes X. 35° W.. with a dip 50° to 60° NE., and appeared to be about 100 feet long on the strike, judging by the shape of the por- tion mined. In this lens cinnabar had been deposited in various ways. It occurs with stringers of pyrite, apparently occupying minor fissures ; it is also seen as a coating in fracture planes. The most characteristic occurrence, however, is where a layer of cinnabar about 1/8" thick, in association with pyrite, had been deposited from solution on the main fissure wall; superimposed on this and indicating a second period of deposition was a layer of silica crystals of equal thickne.ss. The ore from this lens had yielded as high as 150 pounds of mercury per ton. A fine-ore furnace of 4 tons capacity with 2 brick condensers was completed in December, 1915. xV few flasks of quicksilver were pro- duced in 1916, but the property has since been idle. The district north and east is sparsely timbered and watered, being mantled by serpen- tine, but there is a fair growth of timber to the south, outside the ser- pentine belt. Dry wood for fuel costs .$3.00 to $4.00 per cord. In the summer 5 men are employed. Bibl. : Cal. State ]\Iin. Bur., Report XV, p. 658 ; Chapter rep. bien. period, 1915-1916, pp. 64-65; Bull. 27, p. 145; Geol. SuRV. OF Cal., Geol. vol. II, p. 121, U. S. G. S., Mon. XIII, pp 309, 466. Lone Star Mine. Geo. Wapple, owner, Hollister; M. T. Dooling and M. Forcade, Tres Pines, lessees. .Located in the Rancho Real de las Aguilas, 18 miles southeast of Tres Pinos, near Los Muertos Creek. A tunnel said to be 800 feet long has been driven. Rock purporting to come from this mine showed a little cinnabar in altered and iron- stained serpentine, but no ore in commercial amount was reported. There is no reduction equipment. The country rocks are highly altered and silicified sedimentaries. Bibl. : Cal. State Min. Bur., Report XV, p. 659 ; Chapter rep. bien. period, 1915-1916, p. 65. New Idria Quicksilver Mining Company. AV. B. Buckminster, vice president and general manager; home otfice, #70 Kilby St., Boston, Mass. ; H. W. Gould, general superintendent, Crocker Bldg., San Fran- cisco ; John Mocine, superintendent ; Maurice Bowman, assistant super- intendent; mine office, Idria, Cal. It is 40 miles south of west from ^Fendota, and 58 miles southeast from Tres Pinos. The mining prop- erty includes the Idria, West Idria group (3 claims). Sulphur Spring, Molino. San Carlos group (6 claims), covering 240 acres in addition to « g c (U t. p J. bo (U .5 — O a «S c "1 o « (U eg « C U fe 3 U CO a £ Q 3 O bJI C C 3 O u cq •3 c o 2 o QUICKSILVER RESOURCES. 109 other patented land. The ehiims are located in Sees. 28, 29, 32, 33, 34, 35, T. 17 S.. R. 12 E.. and Sees. 3 and 4. T. 18 S., R. 12 E., M. D. M. The elevation at tlic office is 2500 feet (U. S. G. S.) and 4000 feet at Idria Peak, the sununit of the mine hill (see Photo No. 21). Approx- imately 97% of San Benito County's recorded production of quick- silver has come from the New Idria property, it being credited with a total of 306,475 tlasks from 1858 to 1917 (inc.). The mine has been in continuous operation since 1850, and its total yield is exceeded in North America by only that of the New Almaden mine. The present company has been in possession since April, 1895. There are two main ore areas (so to speak), the New Idria group and the San Carlos group, the latter of which lies over 2 miles to the south- eastward of the former. The principal output to date has come from the New Idria though at present ore is also being drawn from the San Carlos mine and transported by aerial tram to the Idria furnaces. For some months during 1915-1916, previous to the installation of the rope- way, ore from the San Carlos was taken out through the 'IMolino Tun- nel.' then trammed around the hill. The portal of the Molino tunnel is about midway between the two main groups. This adit was driven southeasterly about 4000 feet in length and cut the ore body some dis- tance below the old San Carlos workings. A raise was driven and con- nections were completed early in 1915. At several places in the Molino adit near cinnabar-bearing veins, pyrite in small crystals was encountered, stated to assay $1.40 per ton in gold. Much of the ground through which this adit passes is soft and ver^^ heavy to hold open, for which reason it was superseded by the aerial tramway. NEW IDRIA MINE. An idea of the size and shape of the main New Idria ore-body, or rather 'ore-zone,' may be gained from the outline shown on Plate XIV, which was traced from the mine map. On account of the very large number of adits, crosscuts, drifts, levels and intermediate levels, no attempt was made to reproduce them, which would only have compli- cated the drawing. For similar reasons, the outline of the ore zone was taken at three separated levels, only: the 2d, 5th and 10th. This shows a roughly elliptical shape in the upper levels, narrowing, length- ening eastward, and curving toward a crescent shape in the lower levels. The No. 7 level (not shown) has a distinctly crescent outline. This zone has a general dip to the southeast of about 60° to 65°. It varies up to 235 feet wide between walls and 800 feet long on the No. 5 level, and averages about 120 feet wide, with a length of nearly 1200 feet on the No. 10 level. The term 'ore zone' is deemed by the writer a better designation in this case than 'ore-body,' because all of the rock within the outlines PLATE XIV, OUTLINE or ORE BODY NEW IDRIA QUICKSILVER MINE San Ben /to Co. Cal. Sca/e ■■- I inch = ^oo feet 'Tracecf from the mine map, 6ep'f /9/4-. W.E.C. QUICKSILVER RESOURCES. Ill noted is not ore. The ore occurrences are not altogether regular. There are various vein.s, cross-veins, stock-works and impregnations. The main ore-body within the area is stock-works in sandstone and shale, and in places an impregnated sandstone, somewhat harder than the others. As will be noted from the map (Plate XII), the mine is in the Franciscan metamorphic sandstones and shales and some distance Photo No. 22. Flashlight view in square set stope (30' wide) between No. 2 and No. 2'j levels, New Idria Mine. from the contact of the large serpentine area already mentioned. Some of the shale is indurated so that it resembles slate, and was so called in some of the earlier reports. The hanging wall is marked by a black clay 'alta' outside of which is metamorphosed shale, then sand- stone and finally serpentine beyond. The footwall is not as distinctly defined as the hanging, the value frequently not showing a sharp stop- ping off line. 'Wl CALIFORNIA STATK MINING BUREAU. Tile iiiinc work inns arc (•()iii[)li('a1(Ml and iiiiinci'oiis, due to the irreg- ularity of the ore shoots. Consideral)h' timbering is required, especiallx- in th<' larger stopes, where the s(iuare set system is employed (see Photo Xo. 22). The stope shown is 5 sets (6 feet each) wide, or 30 feet. Others arc up to ")() feet S(iuare. The two more important ore shoots developed are at o])i)()sitc ends of the zone. The 'Bodie slioot' is at the east end, the other being known as the West End shoot and has becMi an important producer, especially below the No. 5 level. There are two other veins, known as the Elvan Streak and the New Hope, whicli are quite distinct from the main ore-body. The former cuts across the main zone, while the latter cuts across the hanging wall to the ore-l)ody but stops at the alta. At tlie time of Becker's visit (1884)^ development had not yet proceeded to the point that these relations were as evident as they now are. The Elvan streak is described as a "clean-cut tissure, filled with decomposed attrition pro- ducts which arc impregnated with cinnabar." This gouge material is misnamed 'talc' by the miners. At one point a.ssociated with this vein was a considerable amount of metacinnabarite, which it is stated, amounted to several tons. Tlie Ncav Hope vein was distinctly of metacinnabarite, in the upper levels, where it was very rich ; but it has not been worked in the lower levels. In the main zone pyrite, though not abundant, is associated with the cinnabar, and the gangue minerals are quartz, calcitc and gypsum. From the north end of the New Idria to the south end of the San Carlos, the ore-bearing area has been proven for a length of 2i miles. As already stated, the mine workings are rather complex, if one attempts to consider them in detail. Development is mainly by adits, with connections by raises and winzes. There are ten main levels. No. 1 to No. 10, and a number of intermediates. The No. 10 tunnel, which is the main haulage way for delivery of ore to the furnaces, is 3175' in length to the vein, at which point it is 1060' vertically below the outcrop. There is a total of 15 to 20 miles of underground develop- ment in the coiiipany 's property, including 500(V in the San Carlos. 5000' ill the Molino. (iOO' in the Creek tunnel and over 3 miles of open working tunnels ( crosseiits) in the New Idria. The system of mining in use is that of overhand sloping, and timbering with square sets. Pneumatic stopers and drills are employed; and a certain amount of hand-sorting is done within the mine. On the No. 9 level there is a grizzly 22' long of J," bar iron on edge, sjiaced ^" apart at the top and 1]" at the Ixjttoiu. At that jxiint there are two ehules. one for fine ore and the other for coar.se, leading to No. 10 level, where the cars are loaded and hauled in trains to the runiaees. No. 10 adit is a mile in •U. S. G. S., Mon. XlII. p. n05. QUICKSILVER RESOURCES. 113 U'ligtli from the chutes to its poi'tal. Formerly mules were used for ]uotive j^ower, hut have heen superseded ])y a Iti h. [». Edisou storage- liattery locomotive (see Photo No. 23), for uuderground haulage; while a Ford gasoliue motor is used for surface haulage. The hot ore dis- charged from the furnaces is hauled to the dumps l)y mule-drawn trains. There is a winze from No. 2 level to No. 9, in winch a gasoline hoist operates a skip for tools and timber down to the No. 7. A 25-h. p. distillate engine furnishes the power. Photo No. 23. Ore trains at New Idria Mine. At left, an electric storage-battery locomotive for underground haulage. At right, gasoline motor for surface haulage. At the time of the writer's visit in September. 1917, a considerable part of the New Idria ore going to the furnaces was from the old dumps and from quarries being opened up near the top of the hill along the original outcrop workings (see Photo No. 24). The coarse, waste rock is sorted out, and the finer rock and pieces carrying cinnabar sent to the chutes. ^Material from the dumps between #2 and #5 levels was lianled by mule-train into #5 and dropped down a winze to the chute on jflO level. It was stated that the dump ore cost S^(l' per ton placed in #10 level chute. One shift (day) only was worked here. This out- side ore supply will continue to be drawn upon except during winter months, when two .shifts will be worked underground. An aerial tram- way 3500' long is being installed between ^r> level and the furnace e— 38.540 lU CALIFORNIA STATE :MIXTX0 RTREAr. teriniiial of the Sail Carlos tram. l)ciii<:- of llic same type and size of buckets as the San Cai'h)s instaUation. With this tramway in oper- ation, this surface ore will he moved at even a cheaper cost figure than that (juoted al)ove for the underground route. In excavating- the upper dumps made from the early outcrop workings at least as early as 1860, niucli hroken, slide material is being encountered, some of it apparently from tlie original outcrop: as the writer noted many pieces of very high-grade ore containing massive cinnabar. It is intended to quarry off a considerable portion of the top of the hill. Photo No. 24. New Idria Mine, showing open cuts and dumps being reworked at top of hill. Much of this is to be quarried off. Buildings in center are at portal of No. 2 level. Within the mine during the summer months, the main gangways will all be kept oix^n. \\\\\\ some stoping and development work carried on. They will stope. largely above the #6 level, for some time yet: but expect to break a larger tonnage of lower grade ore. At the portal of #2 level there was formerly a ste.nn-driven sawmill of 2000 b. m. ft. daily capacit\-. Round timliers were used — both pine and cedar — some being cut on land owikmI by the comjiany and some also at a point 11 miles to the south of Idria. within the Monterey Xalional Forest, under contract with the V. S. Foi-est Service. At present. saAved timliei's. cut to dimensions, from Santa Cruz, are hauled in by motor trucks I'l-oin the railroad at Tres Pinos. This freighting is con- tracted at il^lO per ton from Trois I'inos to j|2 level. Hauling from Men- QUICKSILVER RESOURCES. 115 tlota edsts •^9 per ton for miscellaneous freiii'ht and H^IO per ton for oil, witli a drawhaek for ontgoini;' shipments. The t-ompany maintains most of the rei)air work on the roads, thouuh San Benito County does some work on the Tres Piuos road. Equipment at #2 level portal includes a timber framer driven l)y a !l li. p. distillate engine, which consumes 53 gallons of distillate per month. There is also a saw especially set for cutting wedges. The blacksmith shop, here, is equipped with a Waugh drill sharpener. The T2 adit is the main entry to the mine for timbers and other supplies, from which they are distributed to the levels lielow ])y means of the winze and hoist previously mentioned. The power-house is situated around the hill to the left (see Photo Xo. 21) of the Scott furnace. There are two semi-Diesel engines, Type Y, Fairbanks-Morse, 75 h. p. and 50 h. p., respectively, direct-con- nected to a common line shaft, which drive the compressor, also a 60 k. w. generator for lights and furnace blowers. These are also boosted l)y a water-wheel. The generator is on a short-center drive from the line shaft. In the winter time, this drive is dropped, and water used, and the compressor is run by one of the semi-Diesels. Water-power is obtained from San Carlos Creek, the reservoir being above a series of falls, near the Aurora mine, and giving a head of 975 feet. SAN CARLOS MINE. Like the New Idria mine, the San Carlos orebodies are also within the area of Franciscan rocks noted on the map (Plate XII), but appar-^ ently nearer the serpentine contact than tlie former. ^lost of the ore is in sandstone, which is in part metamcrphic. Some of the cinnabar is in seams, and some is disseminated. The sandstone is blocky, and harder than in the Xew Idria mine. There is a serpentine ''dike' Cross- ing through the workings, which also is mineralized. It is considerably decomposed, and is characterized by an abundance of chlorite, an end lu'oduct of the weathering of serpentine. There is some "iine-grained sandstone, and some 'mud-reck.' At the left of the quarry shown in ]*hoto Xo. 25 there is a vein of amethyst crystals cutting through the sandstone. The resumption of San Carlos ore shipments to the Xew Idria fuinaces in September, 1915, is stated to have been the first since 1864. All the work is at present being done above #2 level haulage tiuinel which has been driven clear through the ridge, and is 1030' long. A Ford motor is used for hauling to the aerial tram 1)in. Raises are driven at various points up under the dumps on the surface. It is intended to (juarry off the entire top of the hill down to i^2 level. The ore being sent from here to the furnaces in Septeml)er. 1917, was aver- aging about 0.79^ mercury. 116 CAI.Il'ORXIA STATK :MINING BUREAU. The ore rroni the San Carlos mine is transpoi'tcd to tlie reiliietiou works by a I'aintfi- aci-ial trani\va\'. 2 miles lon0. ixist. QUICKSILVER RESOURCES. 110 Ore sizing. Ore broutiht out through #10 tuuiifl of the New Adria mine is tirst taken to tlie 'screen house' where it is dumped onto a grizzly with H" aperture. The oversize from the grizzly goes to No. 3 coarse-ore furnace. Tlie undersized is elevated to a revolving, wire screen which makes a segregation into 3 sizes: -]-7/8" to H" which goes to No. 2 coarse-ore furnace; — 7/8 to +1/^" "^vhich goes to the Scott fine-ore furnace: — 1/8" which goes to the mill for concentration. Ore from the San Carlos mine is dumped at the tramway terminal onto a grizzly with a 1" aperture. The oversize is sent to the coarse- ore furnaces. A part of the nndersize, up to the mill's capacity, is sent to the concentrators. IMost of the balance is sent to the revolving screen in the screen house. Some of the grizzly nndersize has been sent direct to No. 1 (Scott) furnace. Descriptions of the concentrating mill, the soot mill, and the experi- ments made on flotation with oil, are described in the section of this report on Metallurgy.'' The following summary of operations during the years 1914, 1913 and 1912, is taken from a published' extract from the annual report of the New Idria company for the year, 1914, and is quoted here to show the status before the present high prices of quicksilver were in vogue : 19U 1913 Development, feet Ore treated, tons Quick.-iilver recovered, flasks- Average price per flask Total revenue 12.367 62,578 6,550 ^1 $295,361 Operating expenses ! 340,371 Loss Dividends Previous surplus Surplus carried forward. 45,010 10,000 144,60^] 89,590 9,182 76.993 9,700 ^363,0.54 298,041 *65,013 40,000 119.587 144,600 1912 11,0'80 76,348 9.600 $377,484 303,721 *73,763 120,000 165,824 119,587 *Profit. In 1914, up to Jul.v, 400 men were emplo.ved, when the number was curtailed owing to the low price of quicksilver then prevailing, and one of the coarse-ore furnaces shut down ; so that in September when the writer first visited the property, there were 171 in the mine and 53 on top and around the furnaces — a total of 224 men on the payroll. Since then, however, due to the rise in the price of quicksilver, more are being employed, and all of the furnaces are operating; so that when last visited, in September, 1917. there were 295 men on the pa,^■roll, though 350 men was considered a full crew. ^liners were being paid ij;3.00 per day; muckers ^2.15; furnace men $2.75 and $3.00 with the charge and 'See pp. 275. 339-.342. post. •Min. & Sci. Press., vol. 110, p. 601. Apr. 10, I'.n." 120 CALIFORNIA STATK MINING BUREAU. draw nu'ii working' 8-huur .shifts. A full crew on the furnaces at that time consisted of o2 men. Bill].: Cai.. Statk Mix. Hik., Reports I, p. 26: IV. pp. 88(i, :33i) ; VIII. pp. 48:5-485 : X. p. 51.1: XI. p. 373; XII, p. 365; XIII. p. 59f^; XIV. 1). 228; XV. pp. 660-668; Chapter rep. bien. period, 1915-1916. pj). 66-75; Bull. 27. pp. 9, 22, 125-129, 138-145. 213, 214, 234. 241. 245; Bull. 67, pp. 33, 35. U. S. G. S., Mon. XIII, pp. 64, 189, 215, 291-308, 465; Min. Res., 1882 to 1915. Mm. Res. W. op Rocky Mts., 1868, p. 264; 1869, p. 10; 1870. p. 759; 1871, pp. 58, 528; 1872, p. 523; 1873, pp. 10, 497; 1874, pp. 28, 37; 1875. p. 13. Geol. Surv. op Cal., Geol. Vol. I, pp. 57-60; Vol. II. pp. 113-120. Trans. A. I. M. E., Vol. XXXIII. p. 484. Niesen Group. John Niesen. owner, Hernandez. Two claims, the Tiger and Buck, in Sec. 31, T. 18 S., R. 12 E., and Sec. 36, T. 18 S., R. 11 E., M. D. ]\I., make up the property, which lies on the headwaters of the San Benito River, 5 miles from Hernandez and about 30 miles from Coalinga. The country rocks ai'e the sedimentary formations, sandstones and shales, lying' south of the serpentine area. They have been somewhat indurated by folding. The tunnel on the Tiger claim, which is the only development so far done, was driven 100 feet north- east and 75 feet east and is entirely in an indurated black clay shale, Avhieh shows abundant efflorescences of epsomite and some ferrous sul- phate. A 2" streak of gouge at the end of the drift carried a trace of cinnabar, as did also the rock. There was no other evidence of miner- alization ; no contact had been cut and surface indications were not such as to encourage exploration. Bibl. : Cal. State :\Iin. Bur., Report XV, p. 669; Chapter rep. bien. period, 1915-1916, p. 75. Stayton Mine. Stayton Mining Company, owner; John W. Baxter, president, 3015 Ilillegass Ave., Berkeley; R. B. Knox, secretary and manager, 819 Pacitic Building, San Francisco; E. B. Kendall, suiierin- tendent. This group which is the principal property of the Stayton district is in Sees. 5 and 8, T. 12 S.. R. 7 E.. :\r. 1). :\I.. 15 miles east of Hollister by a good road. The jiroperty has been owned by the Stay- ton company since 1876. and consists of the following patented claims and mines: Stayton. North Stai-. Pacitic, Santa Clara, Fairplay. Green Valley, Cold Spring, Badger Co. No. 2, Last Chance, F. Smith Co., ]\IeLeod Co., a total area of 900 acres, and a length of 3000 feet along the lode. Ore was discovered here in 1870, and was tii-st worked for antimony. The limber siip])ly consists of scattered oak. and water is obtained from springs. The total production is slated to have been QUICKSllAKR RESOURCES. 121 800 to 1000 Hasks, all before 1880, most of which eaine fi-oiii the ( Jypsy vein and was taken out with a 'D' retort. The country roeks are basalt and acidic tnflf breccias, and are under- lain by sandstone. There are six veins, called Grey Buck, Gypsy, Chimney, North Star. Blue Win^', and Pacific. The general strike is approximately N.-S., with dip 60'^ W. The cinnabar values occur near the footwall with associated fissures extending west into the hanging wall. The associated minerals are quartz, pyrite, and stibnite. The last-named is particularly characteristic of the district, and for which, as above noted, the mine was first worked. The mines are located on both slopes of the main ridge of the Diablo Range, the principal cinna- bar deposits being on the east side accompanied by some stibnite; while^ the principal deposits on the west side are of stibnite, with some cinna- bar veins. In the Stayton group, there are six ore shoots, with average lengths of 40' and widths averaging 5'. The maximum width of the mineralized zone is 70', with an average of 35'. The Grey Buck shaft was 250' deep with levels at 70', 150', and 235', and drifts of 150', 775' and 10' in length respectively. In October, 1917, sinking was in progress in this shaft to open up the vein at the 300' level, ore then showing at 252'. Preparations were also being made for a furnace. Equipment includes a 20 h. p. Doak distillate engine, Sullivan straight- line WG3-10"x8" compressor, Murray Bros, direct-connected friction hoist. Water Leyner drills, and Worthington Duplex pump. A total of 10 men were employed, 6 of whom were underground. It is stated that there are 4000 tons of ore on the dump, which will be available for furnacing. Bibl. : Cal. State Min. Bur., Reports VIII, p. 485 ; X, p. 515 ; XI, p. 371; XII, p. 365; XIII, p. 599; XV, p. 670; Chapter rep. bien. period, 1915-1916, p. 76; Bull. 27, pp. 147-149. U. S. G. S., Mon. XIII, p. 380. Tirado Group. Jose Tirado, Hernandez, owner. There are two claims, the Capitola and San Domingo, in Sec. 18, T. 18 S., R. 12 E., M. D. M., 2^ miles by trail northeast of the Alpine furnace. The locations were made late in 1914, as the result of discovery of some rich float by Silvester Tirado. The claims follow the strike of the mineralized zone mentioned in describing the Alpine and Picachos mines. The Andy Johnson corners the San Domingo on the southwest and the IMonterey claims nearly surround the Tirado group. At only one spot has a cropping of rock been found apparently in place and carrying cinnabar. This is on a steep hillside near the southeast end of the San Domingo, in a stream cut where the loose serpentine has been deeply eroded by a tributary 12"J CAI.IKOKMA STATK ^11X1X0 BFREAr. of Clcjir Creek. The rock liei'c is in pnrt a siliceous l)reccia which appears to have Ix'cn I'eeeiiieiited l)y silica (ie|)osite(l from solution whieh ap{)ai'ently also hoi-e ciniiahMi'. oi- was followed hy deposition of cinnabar in the cavities of the rock mass. The cinnabar is found at limes in cavities as diaisy coatinjj's or in nearly solid masses (i" or 8" J thick. Elsewhere the boulders resemble the croi)pinTOup, with an area of 120 acres. The cinnabar occurs in a soft. i)artly serpentinized sandstone, in part as an impreanation and also as seams 1" to l.l" in width. Some pyrite accompanies the ore. The strike of the vein is east of south. There are three adits, all beino- drifts, two of which are on nearly the same level. One i.s in 195', another 180', and the third 80'. There are also 2 or 3 short crosscuts and some small overhand stopes. Wheelbarrows are used to carry the ore to the retort, which is of seven 10-inch pipes set in rather crude walls of mud-plastered rubble masonry. Each pipe treats 100 lbs. of ore daily; and 6 cords of wood are burned per week. The wood is sci*ub oak and iiian/anita. cut closi' to the mine, and costs $1.50 to $2.00 pel' cord. There were four men at work (three of them being Gonzales' sons), two being underground, one at the i-etoi't and one cutting wood. The mine is operated only 7 months each year; and is credited with a total protluction of 119 tiasks of quicksilver to the end of 1917. more than half of which \\as taken out during 1917. Bibl.: Cal. Statk Mix. Bik.. Report XV. p. (571 : Chapter i-ep. bien. |)ei'io(l. 1915_1!)1(). \). 77. QUICKSIIAKR RESOl'RCES. 12:1 SAN BERNARDINO COUNTY. Tlie oec'urrence of (Mnnal)ai' has been noted in at least four localities in San Bernardino Connty. hut as yet there has been no eonimerci^il pi'oduetion i'e[)orted. Mercury Group. W. G. Pinkett, J. L. Wedekind, F. L. :\radden et al.. owners. Dauby via (ioft's. This group of 14 claims is 9 miles northeast from Uanby station, by a good road, and was located in January, 1917. The country rocks are stated to be schist and serpentine. From speci- mens of the" ore examined, it is apparently a breccia which has been re-cemented by deposits from hot springs, which also carried cinnabar. There is considerable reddish iron oxide in some of the material. The veins or mineralized zones, of which there are several, are stated to range from 4' to 10' in width, and cut through a series of 'dikes'. The strike is E-W., with dip S. A 20' shaft has been sunk and a num- ber of superficial prospect holes dug. Myrickite. This is a local name given to a white, gray and bluish, translucent chalcedony containing bright red inclusions of cinnabar. It is found in the southern end of the Death Valley region, 15 miles northeast of Lead Pipe springs, and 45 miles N. of E. from Johannes- burg, on claims owned by F. IM. ^Myrick of Randsburg. Specimens have been mined and cut for jewelry. The chalcedony occurs in 1 lunches and small masses in a lava cap. Some development work was done about 1912 to ascertain its possibilities as a source of quicksilver, l>ut no commercial production has yet been made, so far as the writer is aware. ' Bibl. : Cal. St.vte Min. 'Bur., Bull. 67, pp. 66, 67. U. S. G. S., :\rin. Res., 1911, Pt. II. p. 1039; 1913, Pt. II, p. 651. Specimens of wolframite from the Jack tungsten claim in the Clark ^lountaius near Ivanpah, have ])een found showing cinnal)ar associated. The mercuric sulphide occurs in the middle of a thin wolframite vein, but was deposited at a later time. Bibl.: r. S. G. S., Bull. 652. p. 47, and Plate V. A cinnaljar-bearing ledge on City Creek, six miles from San Ber- nardino, is statcMl to have been worked prioi- to 1873. in which year another prospect was located a little over a mile from the first one. The record does not show definitely if any metal was actually reduced. Bibl.: r. S. (;. S.. M(m. XIII. p. 3S3. :\rix. c^' Sci. Press., vol. 27. I). Kiii. 1S73. 1'J4 CALIFORNIA STATK MIN1X(! BIRKAT'. SAN FRANCISCO COUNTY. The occurrence of luilivc (jnicksilver and einnal)ar in siiinll ijuanti- ties in tlic hills around the ^lission was known in the early days, ])ut no connnereial deposit cvci- developed. About 18f)2. cinnabar was found in sti-ingers and l)uiiches in a siliceous vein enclosed in serpen- tine on Divisadero street near ^McAllister street. Cinnabar and globules of the native metal have also been noted on Twin Peaks. None of these have ever yielded quicksilver in commercial amount. Bibl.: Cal. State Min. Bur., Report XII, p. 3(>6 ; Hull. 67, pp. 18, 35. U. S. G. S., Min. Res., 1892, p. 160. (;eol. Surv. op Cal., Geol. vol. I, p. 78. SAN LUIS OBISPO COUNTY. As noted in the introductory paragraphs to Chapter 4 herein,^ there are four quicksilver districts in San Luis Obispo County (see Map, Plate XV) : Oceanic, Adelaide, Pine ^Mountain, and San Carpojaro. They are all adjacent, and somewhat closely grouped in the north- western part of the county, being located in zones along, the ridges and spurs of the Santa Lucia Range, and separated by mort^ or less barren sections of country. These districts are enumerated above in the order of their importance. Cinnabar from the Sierra Santa Lucia had l)een used by the Indians for pigment for generations before the miner appeared. In 1861 active search by prospectors began and the first location is said to have been made in 1862. The usual rush of miners followed and many claims were taken up. The county became an important producer in 1876, but, although many properties are mentioned as yielding, the records give the individual outputs of only the largest, so that we have not an exact figure of the county's total. At the properties, too, no systematic data was kept and hardly a person is now to be found who can give first-hand information concerning past operations. With the exception of the Rinconada group, and the \)vvv Trail mine, all Ihc mines which have prodnced (jnicksilver are located along the Santa Lucia Range from San Carpojaro Creek in the noi-thwest coi-ner of the county, to the middle of T. 27 S.. R. 10 E.. a distance of about 30 miles. All except the Oceanic and Polar Star are at elevations of over 1000'. The mines may be i-oughly grouped into two classes, depending on the character of oi-e : to the first l)elong the properties like the Oceanic, which exhibit sedimentary formations impregnated with cinnabar and 'See p. 34, ante. I QUICKSILVER RKS(MTRCKS. ..i,;..u 125 •ire of h. ^ -V?- -H.i3^: i Y i~'- • rtia*A^>,.__JUt ,, Vf. iS,j(3. N^"^^ '<;!^:^^' Mill /, ^«\*v\\' • ^ stita en th he »"'ea ')St ^ f:he in ; nic ne. md ;he ler ks. )US ne. he '11- id- lOt \ct lie ' in Jth to >se or of ies -.. > •>/V. moil bainiiqsfl Ql If-KSU^VER DISTRICTS NORTHWTSTf;U.N PORTION OF SAN MlIS OBISPO COUNTY ^mi /GN€OUS I I CHicn scffFSfVTwe 3 MCTAMOf!PHlC CftOPPiNi;s D'a>\n by C.Naramofi Geo/opy hy Wm. /orsfner.r/^* Reprinled from Bulletin 27. QUICKSILVER RESOURCES. 125 carrying' liigli {HTceiitaiiVs of pyrite; tlu' other has vrvs wliieli are highly silieitiecl metaniorpliies (incliuling- serpentine). In a recent report, speaking of the character of work done at some of these mines in the past, Logan- remarks : "Tlie nature of the ore occurrences in most of tlie mines, and the extreme insttibility of the tiuicksilver inarlcet in the past liave no doubt been the chief factors in determin- ing the ruinous policy of exploitation — it lan liardly be called mining — wliich has been followed at a number of the properties visited. The approved method of procedure has been to find a rich pocket of ore, erect a wasteful retorting plant and liurn higli- grade ore only. The result has not been generally realized, perhaps, until the recent I phenomenal rise in tlie price of merciu-y. Many owners find now to their chagrin that tlie.v have neither high-grade ore bodies rich enough to pay for retorting, nor furnaces to treat the nimierous occurrences of low-grade material. Consideration of the costs 1 entailed, and the length of time for which capital would be tied up in erecting and ' bringing a furnace plant to the producing stage, furnish ample explanation for the i lack of activity in mercury mining, in spite of the alluring prices now ruling." OCEANIC DISTRICT. I The Oceanic district is on the west slope of the main Santa Lucia I ridge, and covers the headwaters of the three northern forks of Santa Rosa Creek (Santa Rosa, Cooper, and Oceanic) and the divide between Santa Rosa and San Simeon creeks extending northerly to the south fork of the latter. The geology of this district is complicated, and the rocks belong almost entirely to the Franciscan series, except for an area of overlying, younger formations in the southeastern corner. The most important mine of the district and of the county is the Oceanic. According to Forstner -r "There are several scattered exposures of rhyolite in this district, which apparently, however, have no relation to the location of the ore deposits. There are very clearly defined lines of croppings. having a northwestern direction ; one. starting in the Vulture mine, crosses the divide and runs through a part of Cooper Creek basin ; another, starting southwest thereof, crosses the divide between Cooper and Oceanic creeks, on the ground of the Oceanic No. 2 mine, and runs through the Oceanic mine. ,A third line of croppings lies northeast of the latter, and may be those of a second or back ledge found formerly in the old works of tunnel No. 4 and below in the upper shaft levels of the Oceanic mine. These croppings go some distance farther northwest, but do not reach the divide between Santa Rosa and San Simeon creeks. On this divide a very bold line of croppings starts northward, forming a contiguous line of bluffs about a quarter of a mile long. Hanked on both sides by serpentine, which, however, appear not to carry any cinnabar. The principal material of the croppings is a rather light gray, flinty quartz. "The principal rocks exposed at the surface are, besides the rhyolite above men- tioned, sandstone, shales, some chert, and occasionally some serpentine. The sand- stone is generally much decomposed, with a brownish or greenish gray color, but not nearly as much silicified as in tlie Adelaide district. The deep erosions and the fact that the country is continually sliding, lead to the supposition that a large part of the underlying rock is more or less serpentinized, which is confirmed by the fact that in most of the gulches the hard sandstone is found underlaid by shales or serpentine. "In the Lehman property the younger sandstones are found impregnated with cinnabar in close vicinity to the rocks of the Franciscan series, which would tend to show that the period of ore formation was posterior to that of the deposition of those upper Cretaceous or Eocene rocks. -As this deposition was contemporaneous with, or closely following, a strong process of silicification. the highly siliceous character of the ledge matter of most of the mines is readily explained, the Franciscan series having alread.v undergone a prior process of silification." -Logan, C. A., et al. Mines and mineral resotu-ces of Monterey et al. counties: Cal. State Min. Bur.. Report for biennial period, 1915-1916, pp. 101-10.5. liUT. Reprinted in Report XV, p. fi9S, 1918. 'T^orstner. William, Quicksilver resources of California : Cal. State Min. Bur., Bull. 27, p. 151. 190n. 124 CATJFOHXTA STATK :\IIXlX(i I'.IHEAT. are \ Plat.J< The.V west ' spill secti^"" of U>^ for acti"' beer olaii 187( reeo not syst' ' "'' . can all i San of t 30 1 d ^ /^- /• .IJIXf^HOWt HO /OITHOH /UTrHf//f 11510/ YTl/I JO ) O^lRIHO >X\\ VAV. li?. nf j;)! ovei T \vhi( tst .<7 OMee 'See p. ;i4. (Uiff. QUICKSILVER RESOURCES. 125 carrying- hi.uli [xTreutages of pxritc; the other has ort'S whie-h are hiii'hly silieitied nietainorphics (including serpentine). In a recent r('{)i)rt. speaking of the character of work done at some of these mines in the past, Logan- remarks : "The nature of the ore occurrences in most of the mhies, and the extreme instaljility of the quicksilver market in the past liave no doubt been tlie chief factors in determin- ing tlie ruinous policj' of exploitation — it can liardly be called mining — wliich has been followed at a number of tlie properties visited. The approved method of procedure lias been to tind a ricli pocket of ore. erect a wasteful retorting plant and burn high- giade ore only. The result has not been generally realized, perhaps, until the recent phenomenal rise in the price of mei'cury. Many owners find now to tlieir chagrin that they have neitlier high-grade ore bodies rich enougli to pay for retorting, nor furnaces to treat the numerous occurrences of low-grade material. Consideration of tlie costs entailed, and tlie length of time for wliich capital would he tied up in erecting and bringing a furnace plant to the producing stage, furnish ample explanation for the lack of activity in mercury mining, in spite of the alluring prices now ruling." OCEANIC DISTRICT. The Oceanic district is on the west slope of the main Santa Lueia ridge, and covers the headwaters of the three northern forks of Santa Rosa Creek (Santa Rosa, Cooper, and Oceanic) and the divide between Santa Rosa and San Simeon creeks extending northerly to the south fork of the latter. The geology of this district is complicated, and the rocks belong almost entirely to the Franciscan series, except for an area of overlying, younger formations in the southeastern corner. The most important mine of the district and of the county is the Oceanic. According to Forstner :"■ "There are several scattered exposures of rh.volite in this district, which apparently, however, have no relation to the location of tlie ore deposits. There are very clearly defined lines of croppings, liaving a northwestern direction ; one, starting in the Vulture mine, crosses the divide and runs tlirough a part of Cooper Creek basin ; another, starting southwest thereof, crosses the divide between Cooper and Oceanic creeks, on the ground of the Oceanic No. 2 mine, and runs through the Oceanic mine. , A third line of croppings lies northeast of the latter, and may be those of a s?cond or back ledge found formerly in the old works of tunnel No. 4 and below in the upper shaft levels of the Oceanic mine. These croppings go some distance fartlier northwest, but do not reach the divide between Santa Rosa and San Simeon creeks. On this divide a very bold line of croppings starts northward, forming a contiguous line of bluffs about a quarter of a mile long, flanked on both sides by serpentine, which, however, appear not to carry any cinnabar. The principal material of the croppings is a rather light gray, flinty ciuartz. "The principal rocks e.xposed at the surface are, besides the rhyolite above men- tioned, sandstone, shales, some chert, and occasionally some serpentine. The sand- stone is generally much decomposed, with a brownish or greenish gray color, but not nearly as much silicified as in the Adelaide district. The deep erosions and the fact that tlie country is continually sliding, lead to the supposition that a large part of the underhing rock is more or less serpentinized, which is confirmed by the fact that in most of the gulches the hard sandstone is found underlaid by sliales or serpentine. "In the Lehman property the younger sandstones are found impregnated with cinnabar in close vicinity to the rocks of the Franciscan series, which would tend to show that the period of ore formation was posterior to that of the deposition of those upper Cretaceous or Eocene rocks, ^s this deposition was contemporaneous with, or closely following, a strong process of silicification, the higlily siliceous character of the ledge matter of most of the mines is readily explained, the Franciscan series having already undergone a prior process of sillflcation." -Logan, C. A., et ah Mines and mineral resources of Monterey et al. counties : Cal. State Min. Bur.. Report for biennial period, 1915-1916, pp. 104-10.5, 1917. Reprinted in Report XV, p. fi9S. 191S. 'Forstner. William, Quicksilver resources of California : Cal. State Min. Bur., Bull. 27, p. 1.51. 190.1. 12() CALIKdl^XlA STATK .MINIXd' BlRKAr. ADELAIDE DISTRICT. The Adelaick' disti'ict is on the castri-ii .slope of llic Santa I^uciu ranjie. to the northea.st of the Oeeanie district, and covers tlie liead- watei's of Las Tabhis and El i'aso de Rohh's creeks. '"The rocks of this district belong prominently to the Francisc:in or metamoriiliic series, principally sandstones, with occasionall>' some shales, and in a few places e.xposures of chert l)eds. One wide body of serpentine is found at Cypress Mountain, extending southward past the headwaters of S;inta Rosa Creek. The wliole belt has a northwest trend, and a narrower and shorter belt of serpentine lies west thereof. In the northern part of the district, on the main ridge, north of Cypress Mountain, is an exposure of rhyolite, belonging to the scattered exposures above mentioned; it has a northern trend, but is of relatively small dimensions. "The territory comprising this district must at one time have been covered b>- the" Chico series. It is Ijoundi'd on the east and northeast by the Cliico sandstone, and in places larger and smaller patches of the same are foimd on the top of tlie ridges, the Franciscan rocks l)eing exposed lower down the hillside or in the canons. At the con- tact, the Chico .sandstones are so much broken up and contorted tliat it is impossible to give any idea as to the strike and dip of the beds. "A line of croppings which can readily be followed runs in a northwesterly direction through this district ; though more or less parallel to the direction of the main ridge of the Santa Lucia range, this line is clearly independent thereof. These croppings, starting from the southern part of the district in the Madrone property, run contin- uously through the La Libertad, Josephine. Alice. Modoc, and Elizalieth mines. Then they become much less prominent and only show occasionally in the ridge between Johnson and Carmine creeks and farther north toward the Cypress Mountain group. The Karl and Mahoney mines are situated on a belt entirely disconnected from these croppings. * * * "The cinnabar is often accompanied by sensible amoimts of iron sulphides, which by their oxidation near the suiface give an ochery yellow color to the ore. As a rule, the ore carries more iron sulphides as the cinnabar contents increase. The ore bodies are contiguous to more or less extensive strata of dark-gray to black-colored clays, mixed with bowlders of lighter gray-colored sandstones. They are of the same nature as that of the black clays, generally associated with quicksilver deposits — 'alta.' only here they are almost invariably indiu-ated. Their outcrops frequently accompany those of the ore Ijodies ; they are of a light-gray color, liaving the appearance of a f disintegrated sandstone, traversed by a network of narrow seams of an ochreous yellow color : in places small inclusions of serpentine are found. This material, while contigucus to the ore deposits, is always barren of cinnabar." A large amount of work has been done in this district, especially between 1867 and 1872. Except in the Klaii mine, sntificient develop- ment work has not been done to enable one to .iudge as to the character of the ore bodies in depth. PINE MOUNTAIN DISTRICT. The Pine ^Mountain District is sevei-al niih's to the nortliwest of the Oceanic district, around Pine ]Mountain. and coA^ering the lieadwaters of Arroyo del Pinal and the north fork of San Simeon Creek. The district is characterized by consideral)le ('\i)osures of rliyolite. which appear in a series of knolls. These outcrop.s are not continuous, l)ut are separated bv short exposures of Franciscan formations. To the west lies a wide belt of serpentine, but on the east, serpentine sliows only at tlie Pine ^Mountain group. .Xcar Rocky Butte, the Chico saiul- stone lies close to the igneous rocks. SAN CARPOJARO DISTRICT. The San Carpojai'o district (not shown on IMa1c X \' ) is to the noi'th- wcst of the Pine .Mountain district, in Ihe extreme northwestern cor- ner of San Luis Obispo County and extending over the line into I\ronterey County. Between San Carpo.iaro Creek and the ocean, the formal ion is prominent Iv of a liiLiliK' silicified h'ranciscan sandstone. ^Forstner, op. cit. p. I.0O. (,) r K" KS 1 1 ,\' KK K KSOURCES. 127 To 11i<^ ojist of the creek and fonnin,u' the backbone of the lUHiii ridge is a wide belt of serpentine, along whieli, on its western line, rnn.s a belt (if (Toppings in which cinnabar has been fonnd on the iiorthern water- sIuhI of Salmon Creek. In the basin forming the headwaters of the west fork of San Carpojaro Creek is a minor, parallel belt of serpentine to the west of which are the croi)pings in which the Dntro mine is fonnd. Timber ancJ transportation. Timber is rather scattered and scarce in these districts, except around Cypress Monntain between the Oceanic and Adelaide districts, and in the Pine IMonntain district. The Oceanic mine, at the present time, o])tains its mine timbers and fuel mainly from Pine ]\Ionntain. The transportation outlet for the districts on the west slope is via steamer at San Simeon and Cayucos, 12 to 19 miles; and for the Ade- laide district, to the railroad at Paso Robles, 16 to 20 miles distant on the east. ProcJuction. The total recorded production of the quicksilver mines of San Luis Obispo County is shown by the following tabulation. There are no figures available for the years previous to 1876, though some small properties are known to have been in operation. Their output was combined in the published data with that of other small mines of the state under the heading 'Various IMines'. Quicksilver Pro(duction of San Luis Obispo County. Year 1876 1877 1878 1879 1880 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 Flasks Value Tear 6,428 3,310 2,151 779 $282,8!]2 123,468 70,768 2,358 20 800 101 3.400 101 3,939 384 11,660 394 17,700 515 23.8^^6 840 41.513 3,312 147.215 4,577 1F3 5:'0 4,746 176.616 1905 1906 lf;07 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 Totals Flasks Value ,733 ,511 ,509 867 317 563 569 666 ,160 .266 ,473 227 ,565 47,084 $133,748 128,152 95,743 36.648 15,510 25,476 26,180 27,998 46,667 62,097 125,542 114,724 151,034 $2,079,199 Benton Ranch Deposit. (Lehman Mine.). This property, formerly known as the Lehman, is in Sec. 13, T. 27 S., R. 9 E., 12 miles from Cambria. It is on the continuation of the 'mudrock' zone which has l)i-oven so productive in tlie Oceanic mine. Some develoi)ment work has been done, principally in the fiu'iii of a tunnel in nearly SOO' from 128 CALIFORNIA STATK MIXING BUREAU. ■which short drifts have hccii niii and which are stated to show pi-oni- isinsi" prospects. Thei'e is no reduction (Mniipiiient as yet. Bil)l. : Cm,. St.VTE ]\Iin. IWk., I\e|)01't X\\ ]). 711; ('ha[)tel- l'e[». l)ien. period. IDl.VlDKi. p. 117: Uuil. -!7. p. 161. Cambria Mine (fonuerly tlie Bank Mine). Cambria Quicksilver 'Co., owner; II. K. Gaye, president. 12.");) St. Andrews Place, Los Angeles ; E. W. Carson, agent, Cambria ; located in Sec. 36, T. 26 S., R. ,8 E., M. D. M., 13 miles north of Cambria by road and 11 miles from San Simeon, the steamer shipping point. The holdings consist of min- eral rights on 360 acres. This mine was first exploited in 11)03 by E. S. Rigdon and made a notable output of quicksilver between IDO.") and 1908. It is credited with a total of 4135 tiasks to date. The surface showings were quite poor but exploration underground revealed an ore- body of considerable size, and quite rich. The present owners obtained the property in 1905, but they carried development work for a year before erecting a reduction plant. A tunnel 800' long was driven to use in handling the ore and from this a cut 200' long was driven into the ore-body which proved to be vei-y flat and to consist of a zone of Ijrecciated serpentine about 40' thick, dipping northeast. When the icompany had carried development work underground to the point where they were convinced of the value of the ore body, they erected a furnace. During the 18 months ensuing, operations were very satis- factory. An ore body 180' long. 40' wide and 150' in height was worked out l)y stoping and yielded 3927 flasks. The ore averaged 0.38'/ mercury (7.6 lb. per ton). Square setting was used but not- withstanding this the cost of production per flask was very hnv. l)eing stated as .$26.03. The ore carried little or no iron sulphide and gave little trouhh' in the furnace. Early in 1908 the ore gave out, the body apparently being cut otf either from faulting or sliding. Operations were sus- pended till the fall of 1!:M5. when prospecting began on a series of crop- pings north of and slightly higher than the old mine. There ai'e 3 deposits, more or less i)arallel but not overlapping, l)eing in a sort of step|)ed relation extending northerly and separated by spaces of 4 and 1/8 mile respectively. I'l) to December, 1915, about 1400' of new drifts had be(Mi driven on two levels and crosscuts totaling over 400' as well as about 300' of raises and winzes. All this was done by iiand drilling, and was at times in heavy ground. The main croppings. which show on the surface foi- 70(1' Imve been followed underground for hall' that distance. Suiierlicially a rather flinty am! ochi'eous crop- ping, the appearance uiiderLircund is that of au intensely lirecciated serpentine carrying small stringers of i-icli ore in a siliceous gangue, ( y— 3>r>-io 1:^0 CAUKOKMA STATK MIN'I\(; BUREAU. and (Mialiii.us of ciiiiKibMr on llic sorpeiitine fragments. The miner- alized zone iis I'cvcjilcd ;il tlijil time was about 20' in avera^'e width, witli a dip of about 40"^ N. and strike of a few degrees X. of W. Throughout its width proinincnt sti-caks of chirk clay selvage occnr. and in places t'oim an 'alta,' hnt the country rock is serpentine (;n both sides. As above noted, the gronnd is heavy, and carries a good deal of ' Photo No. 27. Detail of tramway and ore-bin, Cambria Mine, San Luis Obispo County. Photo by E. W. Carson. water in phices. Square setting with i-ound tiinbci-s is cniploycd and close lagging is needed at times. The furnace was |»nt in operation in the snninier of 1915 on surface ore of low grade from the croppings, bnt considerable dif'ticulty resulted, as the rock was a chiyey, highly altered serpentine, eari-ying considerable water. In (October, the reduction of ore fi-oni the niKh'r- groiind woi'kintis beizan. and |>rodueti(>n eonlinned up to Aniinst. IDlii. QUICKSILVER RESOURCES. 131 Since that date, the property has been icUe; but it is reported flint tlun-e are prospects of a reopening- this spring (191S). The reduction e(iuii^inent includes a 50-ton Scott furnace l)uilt in l!K»ti at a cast of $30,000, with 8 brick condensers, one 'D' retort, an >"xl2" Hercules-Blake crusher, and a 40 h. p. Fairbanks-]\Iorse com- pressor. From mine to eru.sher the ore is hand-trammed in one-ton cars. Storage equipment consists of two bins with a total capacity of 1500 tons. To carry the ore from crusher to storage bins, a Broderiek and Bascom two-bucket tramway system was installed in 1915. at a i-ost of .$6,000 (see Photo No. 27). This handles the ore for a dis- tance of 3000' at the rate of 6^ tons an hour and dumps into the upper ore bin from Avhich it is trammed to a lower bin and to the furnace. When operated in 1915-1916, the ore was roasted 24 hours at a somewhat higher temperature than usual. The furnace and con- densers are in excellent condition ; the air is excluded as much as prac- ticable from the furnace and the formation of excessive amount of soot is avoided. Labor was cheap ; miners were paid .$2.50 and muckers .$2.00 per day. Total cost of mining including overhead, in 1907. was $1.66 per ton : liut it must be borne in mind that the cost of square-set timbering contributes largely to this item. A considerable increase in the cost of timber is noticeable in 8 years. In 1907. lagging cost $8 to $12 per thousand; but in 1915, $20. Timber which was then obtainable for 3^^- to 5^' a running foot, increased to 6c. These advances and other slight increases in transportation brought the 1915 mining cost to about $2.00 per ton. Treatment cost $0.82 per ton. 'Jakwood cost $6.00 per ccrd delivered, and the furnace burns 1^ cords per day. The retort burns ^ cord per day for about 7 days per month when the furnace is working steadily. Other general expense, aside from superintendent's salary, was 20^ per ton, making a total oper- ating cost for the 1907 period of $2.68 per ton, and for 1915 of .$3.00 l>er ton. Transportation to or from San Simeon, the shippiiiu' point, was $5.00 per ton. Power for the tram and the rock crusher is furnished hy an Otto gas engine of 12^ h. p. burning distillate. The cost per horsepower- hour was stated at 1^^-. The rock crusher requires two-thirds of the power generated. The total crew last employed was 34. distributed as follows: 22 undergroiind. 4 on toj) at the mine, and 8 at the fiii'iiace. Bibl.: C.\L. St.\te :\1ix Bur., Report XV. pj). 700-705: Chapter rep. hieii. i)ei-iod. 1915-191(i. pp. KHi-lll; Bull. 27. p. 154. Capitola Mine and Santa Monica Claim. Felipe ]\I. Villegas, AVm. Lane and L'has. Pemberton, ownei-s. Klau. This gi-oup is in Sec. 33, T. 26 S.. R. 10 E., M. D. M., adjoining the Klau mine on the ea.st and ]32 C.\I,IK(»KMA STATE MINING BUREAU. south. alxMit 1-') miles west from Paso Robles. Tn tlic Cjipitola, ore was struck at WO' in tlic lower tunnel and followed for 70', being stoped out two sets wide for "J;") in length, in lilKi. Some work was done by lessees in 191 5-1 !)](). but this tunnel i.s now caved. The total output has been 24 Hasks. The formations are the same as in the Klau mine, of Avhich the (yapitola is an extension heiiig saiulstone and serpentine with considerable clay (probably an attrition product). In addition to some cinnabar, the clay carries considerable pyrite in crystals as large as ^" on an edge and often in aggregates of several inches in diameter where the crystals are intergrown. The outcrop is highly ochreous and does not show any cinnabar to the naked eye, but is stated to pan 0.25% quicksilver. The strike is northwest. The reduc- tion plant consists of a 24" 'D' retort with capacity of 1000 pounds of ore per day. and two concrete-covered condensers 4'x4'x6'. lu February, 1918, development work had been resumed. The Santa Monica claim was located by Villegas in 1917, on a parallel vein on the south side of the Klau mine, but on the opposite side of the creek. When visited by the writer in September. 15' of tunnel had been driven. The formations and ore shown ai'e similar to those on the adjoining properties. Bibl. : Cal. State ]\Iin. Bur., Report XV, p. 705; Chapter rep. bien. period, 1915-1916, p. 111. Glaus Group. C. P. and Cecelia Clans, owners, Santa Margarita. This group of 4 claims is in Sec. 28, T. ;}() S., R. 14 E.. M. D. :\1.. 11 miles southeast of Santa INIargarita and adjacent to the Rinconada Group. Claim No. 1 covers the old Pedro mine which has bei'ii i)ros- pected considerably, and ('laim No. 4 has a 75' tunnel which shows a promi.se of ore. The geology of this district is covered in the descrip- tion of the Rinconada group, where developments justify fui-ther work. Assessment work is maintained and in 1915 some ore was taken from near the surface and hauled to the pipe retorts on the Rinconada claims. Bibl.: Cal. State Min. Bur., Report XV. p. 70B ; Chapter rep. bien. period. 191 5-191 (i. [). 112; Hull. 27. p. 166. Cypress Mountain Group. W. S. Forrington. owner. Paso Robles. There have l)een no new developments recently at this property, although assessment work is maintained fi-om year to year. The claims are in Sees. 1 ami 2 of T. 27 S.. \l 9 K.. M. 1). M., about sixteen miles from r'aml)i-ia. All the work done in ri'cent years has been of a (^ri(Mil)l.: Cm,. St.vtk Mix. liru.. Keport W. p. TdT : ("liai)tei' i-ep. hieu. period. li)15-li)l(J, p. JKJ; Bull. No. 27. p. LIT. Josephine Group (also known locally as the Tartaglia Group; also George Mine). .)oe Tai-taglia. owner. Klaii post ofh'ce. It consists of two claims in Sec. 2!), T. 21 S.. H. 1(1 K.. M. J). M., 20 miles west of Paso Rubles, elevation al)out 1!)0()'. The original discovery was made in 1S()2. A furnace was built, and the dum[) indicates consitlerable oi'e was burned, but the j)lant has long since gone to {)ieces, and there are no segregated records of the output. The works are all superficial, the ore being similar to that of the Little Bonanza nearby. There is one tunnel in 150 feet, opening up a vein 12' wide. A small amount of development work is being done to cover the annual assessment. Bibl. : Cal. State Min. Bur., Keport XV, j). 720; Chapter rep. bien. period. 1915-1916, p. 126; Bull. 27. p. 157. Photo No. 28. Old coarse-ore quicksilver turnace. erected 1873, at Keystone Miiie. ijan Luis Obispo County Photo by E. W. Carson. Keystone Mine. IMielan IJi'os.. owners, Cambria. It is on patented l.md on the Ihink of Rocky I'.ntte. in Sec. 1:5. T. 26 S.. K\ S E., M. I). .M.. 16 miles ea.st of San Simeon l)y road. This pi'opertx- was located QUICKSILVER RESOURCES. 135 in the early seventies and has ht'eu eredited in former i-eporls with considerabh' produetion. The furnace and condensers, shown in the pliotograph (No. 28), were completed late in 1874 and the mine pro- duced about 60 flasks of quicksilver in 1875, according to the best information obtainable, and which seems to be the only production of whicli there is record. The furnace is of the old coarse-ore type of 5 tons eapacity and there are 6 of the sheet-iron condensers. The whole plant is quite an interesting relic, as most of such equipment has long since disappeared. The underground workings consisted of a tunnel said to have been about 300' long with a winze sunk from it to a depth of 50', but both have been inaccessible for years. It is stated that the winze was in good ore when work was abandoned. The out- crop shows cinnabar in highly altered serpentine, with a black clay 'alta' and a serpentine footwall, striking E., and dipping 40° N. In 1916 and 1917, some work was done by the owners, intermittently, in driving a tunnel on the level of the old main tunnel to reach the reputed rich ore in the winze. In September, they still had 40'-50' to drive before reaching the old stopes. Bibl. : Cal. State Min. Bur., Reports X. p. 581; XV, pp. 113- 114; Chapter rep. bien. period, 1915-1916, p. 113. Min. Res. W. OP Rocky Mts., 1875, p. 14. Kismet Group. Three claims in Sec. 7, T. 27 S., R. 10 E., M. D. M., in the Adelaide district. Idle. Bibl.: Cal. State Min. Bur., Report XV, p. 114: Chapter rep. bien. period, 1915-1916, p. 114; Bull. 27. p. 159. Klau Mine (oi-iginally calKHl Sunderland; Santa Cruz; also known as the Karl, or Sierra Morena). Owners: Antone Luehessa. San Luis Obispo, E. Bianchini and Wm. Bagby, Paso Robles. The group includes 3 claims and a mill site as well as the mineral rights on cer- tain adjacent land, being in Sec. 33, T. 26 S., R. 10 E.. M. D. M., at an elevation of 1400' on the eastern side of the Sierra Santii Lucia, 16 miles west of Paso Robles. The original Iccation was made in 1868 and it was among the list of producing quicksilver properties in 1874, though no segregated record of output is available till 1876, when the mine yielded 1590 flasks of mercury with a furnaci^ of only 15 tons daily capacity. The recorded production from 187() to 1879 was 1777 flasks. No further output is shown till 1895, although development work was going on for several years [H'evious. the faihu-e to strike ore being due to ill-advised mining methods, according to local re[)oi't. Intermittent work w;is done without iiiiieli production till 1901. In the following year the Klau was the foui-th largest pi'odueei- in the state and the chief mine of the county in jxiint of output \\ ith a yield 136 CALIl'OKMA SI'ATE MINING BUREAU, of approxiiiialc'ly ;>;5()(l flasks, as tlic Oceanic furnace was not started till the fall of the year. Work eontiiined, with an 8-tile, 60-ton Scott furnace and 8 condensers lill lildS, in which year the only outi)ut was made from cleaninu out ohl condensers. Another period of inactivity ensued, and in 1911 the wooden structure over the furnace and con- Photo No. 28a. Klau Mine. San Luis Obispo County. Old stopes and drifts exposed by later, open-cut operations. Looking northeast across the strike of the ore zone. densers was burned (see Photo No. 56, post). The recorded produc- tion of the Klau mine totals 14.213 flasks, to the end of 1917. There appears to Itc a mineralized /xme 200'-300' wide running- through the property N. of W., within which the ore shoots are segre- gated along two priiicipjil lines oi- 'veins'. Large opencuts and extensive undergi-oiiiid workings have Ix'cn made. The geology of the QUICKSILVER RESOURCES. 137 mine was deserilit'd in considerable detail by Forstner/ who states that there were two main ledges developed, running nearly parallel N. 50° W., dipping NE., but approaching each other on the dip. The more southwesterly ledge is locally called the serpentine ledge. Its footwall is a belt of serpentine from 20'-40' wide, rather siliceous in places, to ehalcedonic in character. This serpentine does not appear at the sur- face, but is capped to a. depth of 20'-30' by the croppings of the gouge accompanying the ore deposit. The ledge matter of this orebody is loose, coarsely-granular quartz, carrying iron and mercury sulphides. In this loose quartz are found boulders of very hard ehalcedonic quartz and of a laminated, somewhat calcareous material. Some of the boulders carry visible amounts of cinnabar and pyrite; others are entirely barren, and their relation to the surrounding country rock is not clear. The hanging-wall of this 'ledge,' which forms also the foot- wall of the second ledge above mentioned, is a slightly metamorphosed sandstone. This parallel ledge forms in what appears to be a brec- eiated zone of country rock, probably of cpiartzose character, but hav- ing some clay in it, probably an attrition product. This ore contains considerable pyrite and some free sulphur. Both these ledges are developed by the 60° inclined shaft sunk, it is stated, to a depth of 800', but a large amount of drifting and crosscutting failed to reveal workable ore on the lower levels. These workings became so extensive that a raise to the surface for ventilation was required, and in the course of driving it the best orebody found in the mine was uncovered. These old workings are now largely caved, and inaccessible. In some of the later operations, large open cuts were made (see Photo No. 28A). The cinnabar is crystalline, occurring in part as .stringers, in. part disseminated, and on fracture faces. In some of the old work- ings, particularly in the 'serpentine ledge,' there are abundant efflorescences of epsomite and iron salts. At the southeast end, the ore zone either becomes wider or it splits and the Capitola mine is on one branch and the Mahoney mine on the other. In 1915, a lessee did some superficial work, confining himself to searching for small, high-grade pockets along the outcrop. He waa successful in finding several such, from which the broken ore wa,s hand- sorted, and the richer material hauled on a sled to the retort. This method of handling brought his co.st per ton to about $6, but the grade of the resulting ore was .such as to yield a net profit as high as $28 per ton, some of the rock giving 1.5^^ mercury. Considerable work was done by the owners in 1916 and 1917, mostly in reclaiming ore from around the old stopes and open cuts, and about 30 flasks of quick- ^Forstner, William, Quicksilver Resources of California: Cal. State Min. Bur., Bull. 27. pp. 157-159, 1903. 138 CALIFORXIA STATE MIXING BUREAU. silver [)vv iiioiitli wci'c i)i-()(liicfd in ilu- first hall' of 11)17, with 2 banks of 12-pipe Johnson-McKay retorts (see Photo No. 44. post). At the south end. a new adit was stalled in the footwall side of the ore zone. At the time of tlie writer's visit in Sepieiiil)ei-. 11M7. the retorts were idle, hilt some ore was beiny- aeciiimdated from the o]ierationsof two men who were takinu out hand-sorted ore from the upper edi>e of old fo .stope at the east end. They expected soon to resume retorting. Wood for fuel, mostly live oak, is almndant nearby. Formerly it cost $3.50 to .$4.00 per cortl delivered: l)ut this has increased to .$4.50, being $2.00 for cutting and $2.50 for hauling. Bibl.: Cal. State Min. Bur.. Reports IV, p. 336 (table); X, p. 580: XII, p. 366; XIII, p. 600; XV. pp. 709-711; Chapter rep. bien. period, 1915-1916, pp. 115-117; Bull. 27, p. 157. U. S. G.- S., Mon. XIII, p. 382; Min. Res. 1902; 1906, p. 492; 1908, 1910; 1912. p. 943. Min. Res. W. of Rocky Mts., 1875, p. 14: 1876, p. 20. ]\IiN. & Sci. Press, Nov. 12, 1904. La Libertad Mine. G. A. Trafton, manager, Watsonville. This mine is in the Adelaide district, in Sec. 21, T. 27 S., R. 10 E., M. D. .M., about 20 miles west of Paso Robles, at an elevation of 1900'. In 1915- 1916 it was operated under lease by the Belt Quicksilver ]\Iining Com- pany, which has since dissolved, the mine being at present idle. Con- siderable work has been done, development having been carried on mainly through 3 tunnels: and some fair orebodies were stoix'd out. The company's report of March 1. 1!)15. states that there were 1000' of drifts, raises and slopes. The work underground revealed an irregular ore body dipping at different angles, which had a width of 20' to 25' and has been worked by slopes of 40' to 60' in length. New work was being done in driving a ero.sscut off the lowest drift, which showed some ore. The cinnabar is in the form of small crystals with silica in a highly metamor|)liosi'(l I'ock which has been classed as ser- pentine, and which shows a rather soft clayey texture. The ore is near the contact witli a dark chiy footwall which carries sandstone in small rounded Ixxilders and shows calcite stringers, as well as the charac- teristic epsomitc ellloivscences. The reduction e(|nii)iiient consists of a 12-pipe retoi-t. in good order. Bibl.: Cal. St.u'e :\l!X. Bur., Report XV. p. 700: Chapter rep. bien. period. 1015-1916. p. 106: P.uli. 27. p. 159. Little Bonanza Mine (originally Josephine; lati'i- Alice and Modoc). ]\Irs. Korl)es (an eastern estate), owner: R. \V. I'ntnam. aiivid. San Luis Obispo, Cal. This the lirst (piicksilver mine woi-ked in San Luis Obispo County, consists of 2 patented claims in Sec. 17. T. 27 S.. R. K) K.. M. 1). .M.. about 20 miles east of Paso Robles. and near the QUICKSILVER RESOURCES. 139 sumiuit of the iSaiita Liu-ia divith'; elevation 2(M»ti'. In 1915 and 1916, it was operated under lease by E. S. Rigdon & E. liianeliini of Cambria, who produced a fair amount of metal witli a 12-pipe retort; hut the property was idlr wlicn visited by the writer in September, 1917. The original discovery is said to have been made in 1862 liy ]Mex- icans. The temporary closing of the New Almaden ]Mine prompted the purchase of this property by ^Messrs. Barron & Company. Con- siderable money was spent in development and an 8-ton furnace was put up. An adverse report on the property by its superintendent, and the reopening of the New Almaden. led to the abandonment of the Josephine. In later work, several bodies of ore were taken out by stoping: two in particular showing a thickness of 10'. The ore shoot has been stoped out for about 200' along the strike, which is S. of W., with dip S.. about 30^ at the surface, but steeper in the lower tunnel. It appears to be cut off by a cross slip near the lower level which is down about 200' on the dip of the vein, but the displacement may not be great. The stopes are np to 20' wide. Much of the work done, however, has taken the form of gouging out rich bunches. These stopes have broken through to the surface. In the upper workings, there were 2 parallel shoots stoped out, leaving a pillar of 15'-20' between. The ore is in the form of a network of cinnabar veinlets, and cinnabar on fracture faces, in a silicified, altered serpentine. On the footwall there is a gouge with brecciated masses. The hanging wall is serpentine. There has been no stoping, as yet, on the lowest level. Bibl. : C.vL. State Min. Bur., Reports X. p. 580; XV. p. 711-. Chapter rep. bien. period, 1915-1916. p. 117; Bull. 27, p. 154. ^IiN. Res. W. of Rocky Mts., 1875, p. 14. Madrone Mine. John Carmine, owner. Cayucos. This is in Sec. 22, T. 27 S., R. 10 E.. adjacent to La Libertad mine. It was worked about 1900 and considerable mercury recovered by retorting, lint no depth was attained in any of the operations. The croppings are similar to those in the Little Bonanza, and La Libertad, Some small rich bunches of ore are present both in the characteristic siliceous gangue and in a softer ochreous material, and the wall rocks are similar to those in the two properties above mentioned. In addition to the mineral found in place, there are several bodies of material scattered over the property where free mercury can be panned out. It is found in the loose soil and is probably the weathered product of a one-time outcrop. Samples of this, taken from several places by ^Ir. ^rerrifield. the former superintendent, gave from 1^ to I 140 CALIFORNIA STATE MINING BrREAU. 2^ pounds (if mercury per ton in the i-etoi-1. There would seem to be justification for more extensive wdik on this ])roperty. Jiihl.: Cal. State Min. I'.ik.. Rcjxirt XV. p. 712; Chapter rep. hien. period, ]915-191ti. |>. 118; Bull. 27, p. IB]. Mahoney Mine (also called Gould; also Buena Vista). Miss ^Fary I. 'Toole, owner, San Jose. It is in Sec. 83, T. 26 S., R. 10 E., M. D. M., 14 miles west of Paso Robles; elevation 1140'. It is on the extension of the Klau ore zone, to the southeast. There is a tunnel said to be in 400', but it was inaccessible when visited by the writer. No work has been done for some years, Bibl. : Cal. State Min. Bur., Report XV, p. 712 ; Chapter rep. - bien. period, 1915-1916, p. 118; Bull. 27, p. 161. Marquart Ranch Prospect. John Marquart, owner, Cambria. There are cinnabar-bearing croppings on the jMarcjuart ranch, 2 miles north- east of the Oceanic mine. Undeveloped. North Star Mine (Santa Maria). In San Carpojaro district, in Sec. 13, T. 25 S., R. 6 E., M. D. M., southeast of the Polar Star mine. Idle for years. Bibl.: Cal. State Min. Bur., Report XV, p. 712; Chapter rep. bien. period, 1915-1916, p. 118; Bull. 27. p. 162. Oceanic Mine. Murray Innes, owner, 217 Kohl Building. San Fran- cisco; Ellard W. Carson, manager, Cambria. It is 5 miles easterly from Cambria and comprises three patented claims containing 60 acres, also the mineral rights on 400 acres of ad.joining land. The property is in Sees. 15 and 21, T. 27 S., R. 9 E., on Santa Rosa Creek. The patent for the three original claims was granted in 1865. being signed by President Lincoln. The mine has had an interesting and instruc- tive history. In 1875 it was taken hold of by a corporation who began' developments on a very ambitious scale. A large force of men were hired and 600 acres of timber land purchased. Seven tuiuiels were driven and a body of good ore opened u}). A Louis Jaiiiii furnace was built in 1875. The first recorded production occurred in 1876. when the yield was 2358 flasks. The metal at that time was worth about $1.50 per pound ;iiid the cjuicksilver mining industry was at the high- est pitch of pros|)('city which it has evei- (Mijoyed previous to the present war-boonL During the period of 187()-187!) inclusive, the Oceanic produced 7391 flasks. Sharj) declines in price. Iiowevei", brought quicksilver to less than 40f'' a pouiul in 1882 and left only 6 mines in the state which could produce without loss. The ()ce;inic had prac- tically closed down three years l)efore. jiiid riMiiaiued idle till 1!)02, when ;i new company assumed ownei'ship ;ind ei'ccfed a 50-ton Scott furnace. QUICKSILVER RESOURCES. 141 ^ Production was resumed soon after, aiul was inaiiitained more .stead- ily than at any other property in the county. In 1906 the Oceanic was one of the six chief producers in California and in 1908 it is also men- tioned as one of the nine leaders, in spite of the depressed condition of the industry. . In 1909-1910 the mine was operated by lessees and in the latter year was the only producing quicksilver property in the f Photo No. 29. Open cuts at Oceanic Mine, looking northwest along strike of ore zone. In foreground, top of stope caved through to surface. county. Al)out this time the coarser sandstone ore gave out. The rock on the hanging wall side of the old vein (and easterly on the strike) proved, on exploitation, to be a finer-grained material, carrying cin- nabar in much smaller percentage than the old ore. It was erroneously named a shale 'mudrock.' In 1912. the present owner took control of the property, rebuilt the furnace, and made a small production that year, besides developing a vei-y large orebody of this low grade 142 CAUFORXIA STATK MINING BfRKAr niatt'rinl. Tii l!)l»;. Kdward A. Clark. v\ al.. oT New York, took a bond on the property, built a SOO-ton coiiccntratino- niill.^ a new aerial tram- \va.\- ol' greatci- capacity llian the old one. and a second 50-ton Scott furnace. They gave up Ihcir boud cai-ly in 1!'17. aud 1hc property with iniprovcnicut.s reverted to limes. The total recorded outpnt of the Oceanic iidnc to llic end of 1!)17 lias l)een 28.251 flasks of quick- silver. Mine. The ore is a dark-gray, fine-grained sandstone. Avhich contains enongh calcite to cause marked slaking on exposure. Petroleum is also associated. There is considerable pyrite. and tlie cinnabai" values are Photo No. 30. Micro-photograph of diorite-gabbro at the Oceanic Mine. ■ 60 diam. magnification. Photo by S. A. Tibbetts. SO finely disseminated as to be hirgely invi.si])le undergi-ouud. luit if specimens are taken from any part of the ore bk)ck. reduced on a buck- board and panned, a surprising prospect is obtfuned. 'I'hei'e ai'e also occasional crystalline accunndations of cinnabar on fracture faces. This ore is quite uniform in value. The ore strikes NW-SE, (see Plate X\'1I), and the dip is nearly vei'tical tli(MiL;li in |)laces it reverses itself, being mainly KK. (see IMioto. No. 29). It is from 15' to 00' wide, being 40' wide at the top ol' tlie hill. The hanging-wall is ser- pentine and Mie footwall. shale. ()n the southwest side, and more or less parallel to the orebody, is a body of igneous rock of the diorite- gabbro series (see Photo \o. :{0). The sam|)le from which the thin- •See descriiition. p ;!.'iO, pos^ IIVX HTAjq RAISE - ' ■A.w-'.ji ' . I ... I l l I . n u mm n H i wjti w i wi w II I I I M'DTJIMAHi].. klAJ' 3 HI 3HTfc-' .lUAD,Am 3JAD< diei.3M \\*i>^ot> ^ .t) . \^ V>^<:\«\\ • r»M HlTlj.,\j»..»^j»».* G-r n,i| PLATE XVII. r^ D QrirKSITA'ER RESOURCES. 143 set'tion was cut was obtained bv tbe writer on the 250-foot level (i.e. 150' below No. 4 tunnel). There is an expc^nre of the same or another body of similar rock on tlie road between the mine and the furnaces (see Photo 31). It has not been opened up sufficiently underground, nor did the writer have sufficient time for tield study to ascertain if this diorite-gabbro has had any connection with tlie mineralization of the orebodies. The innnediate walls of the orebodies are composed of harder sand- stones than the ore itself: that on the northerly side being gray, and that on the southerlj^ side being darker and more compact ('barren mud- rock'). The actual ore boundary is merely a slip, in the sandstone, and very difficult to follow. In the earlier-worked 'sand' orebody, the north wall was well defined, being an 'alta' of black clav slate, but it Photo No. 31. Plant of Oceanic Mine, San Luis Obispo County. The light streak below the arrow is the line of the open cuts. ran out to a point at the west end as the 'sand rock' ran out. The best ore was obtained next to this alta. At the westerly end of the prop- erty, these formations can be traced acro.ss the cailon of Santa Rosa Creek. l)ut no ore values have been found there. The methods of mining used are a caving system and that known as sublevel slicing. As used at the Oceanic, two main or working levels v\ere driven ]50' vertically apart along the strike of the orebody for 300'. These are well timbered. At vertical intervals of 25' between the two main levels, sublevels are driven. Mining begins on the far end of the block, where a raise has been cut through. The angle of drilling is such that the ore can fall freely to the lower level, and at the same time permit easy handling of the machines. Holes are driven above and below on a slice and the two rounds of shots break through it, and so on through the block. There are several adits, but the prin- r -^ 3XI«TC' 3MT ailOjA WOlTMd 3HIM DIHA300 OViVM .1 >w^^3i ^i\Aw^tv«?, -A '< V QT'TCKSIT-VER RESOT'RCES. 143 section was cut was obtained by tlio writer on the 2r)0-foot level (i.e. 150' below No. 4 tunnel). There is an exposure of the same or another body of similar rock on the road between the mine and the furnaces (see Photo -M). It has not been opened up sufficiently underground, noi- did the writer have sufficient time for field study to ascertain if this diorite-gabbro has had any connection with the mineralization of the orebodies. The immediate walls of the orebodies are composed of harder sand- stones than the ore itself: that on the northerly side being gray, and that on the southerly side being darker and more compact ('barren mud- rock'). The actual ore boundary is merely a slip, in the sandstone, and Yery difficult to follow. In the earlier-worked 'sand' orebody, the noi'th wall was well defined, being an 'alta' of black clay slate, but it Photo No. 31. Plant of Oceanic Mine, San Luis Obispo County. The light streak below the arrow is the line of the open cuts. ran out to a point at the west end as the 'sand rock' ran out. The best ore was obtained next to this alta. At the westerly end of the prop- erty, these formations can be traced across the caiion of Santa Rosa ('reek. l)ut no ore values have been found there. The methods of mining used are a caving sj'stem and that known as sublevel slicing. As used at the Oceanic, tw^o main or working levels \vere driven 150' vertically apart along the strike of the orebody for 300'. These are well timbered. At vertical intervals of 25' between the two main levels, sublevels are driven. ]\rining begins on the far end of the block, where a raise has been cut through. The angle of drilling is such that the ore can fall freely to the lower level, and at the same time permit easy handling of the machines. Holes are driven above and below on a slice and the two rounds of shots break through it. and so on through the block. There are several adits, but the prin- 144 CAKII'OHNIA STATK MINING BUREAU, cij)al opei-ations arc L-arried on through No. 4 tuimol. A vc-rtieal winze extends 150' below the level of this adit. Durincf the Clark operatioiis in 1!)1()_1!)17, the ground ])eoan caving on them aiid i^ol Ix-yond control, so that it became impossil)l(' to use the Braun shaft. 'I'hc "New Shaft' (winze) was sunk by the present man- ager and connections made on the 150' level with the Braun workings. Then a new gangway was driven in the north wall and parallel to the old 150' drift which w^as in ore, and from tliis crosscuts were being driven every 20' to the old level. Through these crosscuts and new gangway the caved ore was being reclaimed, when visited by the writer in September, 1917. The material simply required shoveling into the cars and tramming to the shaft, only occasionally having to bulldoze a chunk too large for handling. This caved ore was being delivered on the 150' level to the hoist at a cost of 30^ per ton ; and on the No. 4 tunnel level it was being delivered to the chute at the same figure. Hoisting and tramming to the crusher, costs about 15^ per ton. The hoist is on No. 4 tunnel level. The total operating cost on this ore, exclusive of overhead charges and development, was approximately $1.50 per ton. In one portion of the mine, called the 'Wright stope', this caving of the orebody had extended through to the surface (see Plate XVII, and Photo 29). In 1917, up to September, approx- imately 2400' of development work, mostly not in ore, was done at a cost of $2— $4 per foot, to make available this large tonnage of caved ore. When visited by the writer, one shift only (day) was required in the mine to keep the two 50-ton furnaces going. Square-set stoping costs $1.50 to $2.00 per ton of ore extracted. The machine drills used are principally IngersoU-Rand jack hammers. On the No. 4 tunnel level, in the north-wall side about 50' NE. from the Braun shaft, a new cinnabar occurrence of a ditferent type from the main orebody was cut in the course of driving the new gangway to get back of the caved ground. The cinnabar and associated minei-als have crystallized in open fractures in a hard siliceous material, possibly chert or a highly silicified serpentine. An interesting sequence of deposition is shown. First pyrite was precipitated, followed in orde? by calcite, coarse crystals of cinnabar, and finally scattered euhedral transparent crystals of calcite. This occurrence will be further pros- pected to determine its extent, and its i)ossiblc i-elation to the main ore- bodies. At the portal of No. 4 tunnel are located the blacksmith shop, com- pressor, crushers, and tramway loading terminal. The rock bi-eakers are set at 3" and 2i" openings. The ore is transported to the furnace bins one-half mile l)y a Painter aerial tramway, having twenty 10-cu. ft. buckets, and a capacity to dclivci- LM) tons per hour. It has a ehain drive, but the dilTercnce in elevation between terminals is such that QUICKSILVER RESOURCES. 145 occasionally .some power is developed and the brakes have to be used. The old aerial tram, a Hallidie, having 1| eu. ft. buckets and a capacity of 50 tons per day, is still retained in repair for use in case of emergency. The buckets on the new tram are dumped by hand (see Photo No. 32). The ore bins at the discharge terminals of the two trams have a combined capacity of 1500 tons. Reduction equipment. There are two '50-ton' Scott fine-ore furnaces, the second one having been built in 1916. It is stated that the first furnace, which was built in 1902, cost $30,000. the brick having been made at the mine. The Photo No. 32. Tramway unloading terminal at Oceanic Mine. second one cost $50,000, the brick being shipped from San Francisco. A careful check recently made on the tonnage, with an average mois- ture allowance shows these two furnaces to be handling an average total of 90 tons of ore daily. A heads sample of the ore is taken from each bucket at the tramway loading terminal, and the tailings sample is taken from the car at the furnace discharge. These samples are quartered down weekly and sent to an assayer in San Francisco. A portable screen with 2" sciuare opening is laid on top of the furnace- charging ore car while filling it at the ore-bin chutes. The coarser 10— 3S540 14G CALIFOHMA STATE MINING BUREAU. pieces are rejected. The furnaces have a special fume trap, which is described in the section of tliis report on ]\Ietallurgy.^ The first condensino; cliamber on each furnace is of brick. On the older furnace, #2, pi and #4 chambers are of wood, the following three being of brick. On the new furnace, the brick chamber is followed by two large wooden condensers, each 16' wide x 40' long x 23' high. These condensers are constructed of 1" tongue and groove redwood or pine, with a IV' floor; not painted; and held together with wooden pins instead of nails. There is an aii'-inlet hole in #1 condensing cham- ber. The old brick condensers show considerable efiflorescence of salts on the outside. This is said to show a noticeable increase when wet ore is being roasted. There is a dead-end, wooden condensing chamber about 20'x20'xl6', connected to the series on No. 1 furnace, but it seems to collect very little mercury. It was built as an experiment. Soot is treated in 'D' retorts, being charged in large sheet-iron pans or 'boats.' There are two 'D' chambers set in brick work with a single fire-box under their center. They obtain 40% of the total quicksilver yield from the soot. The retorts are operated 3 weeks of each month. No extra labor is required, as the Scott furnace shift-men also keep the retorts going. Repairs are slight, and 10 cord.s of wood per month are consumed as fuel. In 1915-1916, wet concentration of the Oceanic low-grade ores was tried, but has now been discontinued. A detailed description of those operations is given elsewhere herein,- as is also a discussion of furnace operation costs. ^ Power for the mine and crusher plants is furnished liy distilhite engines, at a cost of $25 per h. p.-year in 1915, but this has doubtless increased somewhat since. In that year, labor underground and at the furnace was paid .$2.50 per day, and 2 foremen, $4.50 each. In Sep- tember, 1917, muckers were being paid $2.75 and miners $3.25 per day. A total of 57 men was employed, including 27 underground. 13 on top, and 17 at tlie furnaces. Bibl.: Cal. State I\riN. Bur.. Reports IV, p. 336 (ta])le) : YIII, p. 531; X, p. 580; XII, p. 3(iti: XIII. p. 600; XV, i)p. 712-718; Chapter rep. bien. period, 1915-1916, pp. 118-124; Bull. 27. pp. 151, 162, 243. U. S. G. S.. Mon. XITI. p. 382. :\riN. Res. W. OF Rocky Mts., 1875, p. 14; 1876. p. 20. A. I. :\r. E.. Bull., Fel)., 1915, pp. 497-504; also Trans, vol. LI, i^i). 110-119. Eng. & MiN. Jour., vol. 102, p. 512, Se])t. 16, 1916. Pine Mountain Group. Mrs. Plioebc A. Hearst, owner, San Fran- cisco. Tliis gi-()U|) (»r 22 tiiininij claims and sevei-al ti-acts of timber 'See p. 241. post. "See p. 338, post. •See p. 2H. post. QUICKSILVER RESOURCES. 147 land on and around Pine ^Mountain, in Sees. 3, 10, and 11, T. 26 S., R. 8 E.. M. D. M., includes the Buckeye, Little Almaden, Pine Moun- tain, and Ocean View prospects, 11 miles east of San Simeon. The principal workings are on the east side of the body of rhyolite forming Pine Mountain, which is the most southerly of three eruptive cones, close together, but not connected and of slightly varying material, lying along the backbone of the main ridge. The country rocks are of the Franciscan series. There has been no work done on these claims for years; and the holdings are now occupied by the cattle ranges of the Hearst estate. I Bibl. : Cal. State Min. Bur., Reports VIII, p. 531 ; X, pp. 580, 581: XV, p. 718; Chapter rep. bien. period, 1915-1916, p. 124; Bull. 27, pp. 163-165. Polar Star Mine (also called Santa Clara, or Black Hawk). This group of two claims, relocated in 1915, by A. L. Carpenter of San Luis Obispo, is in See. 13, T. 25 S., R. 6 E., M. D. M., in the caiion of San Carpojaro Creek, 3 miles above its mouth and 15 miles north of San Simeon. It has been worked sporadically since 1870 by various owners, the earlier operations being confined to retorting float material. Between 1890 and 1900, E. S. Rigdon and others, tried hydraulicking in an attempt to expose a vein. This has not yet been uncovered, although the surface dirt for several hundred feet up the steep hill- side is said to carry cinnabar to the extent of 0.1%. Logan^ states that he "found no ore in place, but in the creek bed in the center of the claims he found a boulder of over a ton m weight which shows prospects of cinnabar, and some pieces ot the ore which were left by the last operators contain good amounts of the sulphide Ihe rock in which the cinnabar makes its appearance is extremely hard, being apparently a highly metamorphosed and silicified sandstone. The large boulder no doubt came from either hillside nearby." Bibl. : Cal. State Mix. Bur., Reports X, p. 581 ; XII, p. 366 ; XV, p. 718; Chapter rep. bien. period, 1915-1916, p. 124; Bull. 27, p. 165. Rinconada Mine (also called San Jose Valley Mine). Mrs. Theresa L. Bell, owner, San Jo.se; C. B. Claus, lessee, Santa Margarita. This group of 4 patented claims, named San Jose, Rincon, Tres Amigos, and Livermore, is in Sees. 21 and 28. T. 30 S., R. 14 E., M. D. M., 11 miles southeast of Santa Margarita. It is, as noted in the introduction to San Luis Obispo County, quite apart from the main quicksilver dis- trict of this county which is in the northwestern part. The property was located in 1872 and in 1876 was equipped with a furnace of the old sheet-iron type, with 5 sheet-iron condensers. The designer attempted to keep the mercury vapor separated from the fuel Logan, C. A., et al.. Mines and mineral resources of Monterey et al. counties: cal. State Min. Bur., chapters of State Mineralogist's report, 191.5-1916, p. 125, 1917. 148 CALIKOIJMA STATE MINING BUREAU. smoke, but the only definite result achieved appears lo have been the salivation of the furnaee employees. It is said that little if any quick- silver was recovered, and the plant was abandoned in 1883. In 1897, two benches of 10-pipe retorts were put up ; some rich ore treated and a small production made, but no definite figures of which are now obtainable. The upper tunnel, said to be 75' long, is now caved and inaccessible. Two intermediate adits w^ere driven 40' and 25' respec- tively, and there is a lower adit 400' long as well as several shorter ones and open cuts. The country rock is largely serpentine, but some shale exposures are found in the bed of a creek about a quarter of a mile west of the main M'orkings. The mine is in a basin formed b}^ a bend of the mountain ridge. Through this basin runs a line of outcrops showing boldly in places. The face of the lowest adit is at the contact of the serpentine and sandstone. The ore thus far worked is stated to have occurred in small rich bunches, at times nearly solid cinnabar. Pyrite, calcite, dolomite, quartz and organic matter accompany the ore. It is to some extent disseminated, Init usually occupies cracks in the rocks, which it often only partly fills. A former employee at the retort says that some ore gave 5 flasks from 2^ tons and in a few cases as much as 65 to 80 pounds were obtained from a single charge in one pipe. Some samples which have been assayed carried a little silver and iron sulphide with $2.60 per ton in gold, besides the quicksilver. A little ore was mined in 1915 and hauled to the retort on a sled. The capacity of the retorts is 3-J- tons per day. Fuel is easily obtainable nearby, but timbers for mining are scarce. Bibl. : Cal. State Min. Bur., Reports X, p. 581; XII, p. 866; XIII, p 531; XV, p. 719; Chapter rep. Men. period, 1915-1916, p. 125; Bull. 27, p. 166. U. S. G. S., Mon. XIII, p. 381. Sunset View Mine. In San Carpojaro district, in Sees. 13 and 18, T. 25 S., n. 6 E., M. D. M, southeast of the North Star mine. Idle for years. Bibl.: Cal. State Min. Bur., Report XV. p. 720; Chapter rep. bien. period, 1915-1916. p. 126; Bull. 27. p. 1(57. Vulture Mine. Mark Rickles, owner, Cam])]-ia. Tt is on Vulture Mountain, in Sec. 24, T. 27 S., R. 9 E., M. D. M.. 10 miles east of Cam- bi'ia. The development has been insufficient to uncover any ore, although there are prospects of cinnabar. Only a little superficial and desultoiy work has been performed. Tt is located on an outcrop of QUICKSILVER RESOURCES. 149 black, flinty, siliceous rock, more or less ehar.ued witli cinnabar, in a belt of serpentine. Bibl.: Cal. State Min. Bur., Report XV. p. 720; Chapter rep. bien. period, 1915-1916. p. 126; Bull. 27. p. 167. Warren Ranch, adjoining the Oceanic Mine. AV. W. Warren, owner. Float ore occurs over an area ^ mile wide down a steep hillside from near the summit. IMurray Innes, of the Oceanic Mine, drove a 60' tunnel into the hill in an effort to find an orebody in place. Wm. Spargo also drove two tunnels totaling- about 200', but no deposit of any value was uncovered in either instance. Bibl.: Cal. State Min. Bur., Report XV, p. 720; Chapter rep. bien. period, 1915-1916, p. 126. William Tell Mine in Sec. 32, T. 26 S., R. 10 E., M. D. M., west of the Klau mine, shows no new development in recent years. Bibl.: Cal. State ]Min. Bur., Report XV, p. 720; Chapter rep. bien. period, 1915-1916, p. 126; Bull. 27, p. 168. Wittenberg Mine in Sec. 8. T. 27 S., R. 9 E., M. D. M., near the Oceanic mine, has been idle for a number of years. Bibl.: Cal. State Min. Bur., Report XV, p. 720; Chapter rep. bien. period, 1915-1916, p. 126 ; Bull. 27, p. 168. SAN MATEO COUNTY. Cinnabar was early noted on the Corte de Madera Rancho near Searsville in San Mateo County, west of Palo Alto. Some prospect- ing was done about 1863, but nothing of commercial value was found. About 1910, minute yellow crystals of the mercury oxychloride, eglestonite (Hg^CLO), were identified by Rogers,^ about 5 miles west of Palo Alto in seams and cavities in a similar siliceous material to that so common in the serpentine of the cinnabar districts. The crystals showed on analysis 88.0% Hg. and 7.4% CI, and were asso- ciated with cinnabar, mercury, calomel, dolomite, magnesite, opal and quartz. This is evidently the same locality as the first-mentioned, above. Bibl.: C-VL. State Min. Bur., Bull. 67, p. 61. Geol. Surv. op Cal. Geol. vol. I, p. 71, 1865. Amer. Jour. Sci., vol. 32, p. 48. 'Rogers, A. F., Eglestonite from San Mateo County; Amer. Jour. Sri., vol. 32, p. 48. 1911. 150 CALIFORNIA STATE MINING BUREAU. SANTA BARBARA COUNTY. Quicksilver was discovered in Santa Barbara County at the Lo.s Prietos mines in 1860. Seven years later i.ji MAP NKW AI MINING ] SANTA C CALIF! Accompanying Stai Bulletin - ^ \ V --(;>-^- V (^ V V w V V w V \# •SVA^rbo\V\ ^- QMn-^fc BPPI^^ SSdIO p. 154 PLATE XVm. .School -i^tl^^^-i^i • Vt" '• >\\^!5f'T.«.»^«s/ ^ - M.neMill 3 7';.- MAP OF NEW ALMADEN MINING DISTRICT. SANTA CLARA CO. CALIFORNIA — Scale — . „ . , Accompanying State Mining Bureau Bulletin NS 78 38i*l p, 154 Rhyoldc Serpentine Metamorphic Series QUICKSILVER RESOURCES. 155 that the fissures wherein the orebodies have formed have invariably a serpentine footwall : hence the serpentine must be considered to occur underground in a con- tinuous body tlirough this entire territory and to be in places covered by overlying sandstones "and shales. Southwest of Capitancillos Creek lies another parallel exposure of serpentine, contiguous to which the outcrops of the Costello mines are found. The Santa Teresa and Bernal mines are located in the serpentine of the Santa Teresa hills, and the North Almaden or Silver Creek mine close to those of the most northern ridge. In the latter a great part of the serpentine is very highly altered by silicificalion, as also the sandstones, a great portion of the rocks being jaspilites.' The western slope of the adjoining Mount Diablo range is nearly e.xclusively formed of shales. "In this district the occurrence of cinnabar-carrying orebodies is clearly closely allied to that of serpentine, and as the New Almaden was the first extensively worked quicksilver mine in California, tliis association explains the reason why, for a con- siderable lapse of time, cinnabar ores were, in the opinion of most quicksilver miners, considered related to this rock formation. The croppings consist of a more or less weathered material having usually an ochreous color from the o.xldation products of the iron sulphides, and traversed by a network of quartz seams, from a knife blade to quarter of an inch wide. Overlying the ore bodies is almost invariably found a body of clay, generally black, and containing more or less inclusions of a dark-gray sand- stone. As this ciay overlies the ore bodies it has received the name of 'alta' (Spanish for 'high' or 'upper'). At the surface this 'alta' crops as a light-gray material, resembling disintegrated sandstone, traversed by a network of very thin, yellowish- brown seams, often very much like a bunch of very fine roots. In places the same material can be found in the New Almaden mine several hundred feet below the surface, forming part of the 'alta.' * * * -phe rocks of the Franciscan series in tills region show a great amount of silicification. The chert beds are, however, almost entirely unrepresented. "To the west of the New Almaden ridge a belt of bedded sandstone is exposed. The beds are from 3 to 5 feet thick and interbedded with thinner beds of shale. * * * The country west of the New Almaden ridge and south of Capitancillos Creek, belonging to the Gabilan mountain system, consists almost exclusively of the sandstones and shales of the Franciscan series with occasionally some jaspilites. * * * TVest of the serpentine belt which lies west of the New Almaden ridge, south of Costello's house, a small exposure of glaucophane schist was found. A body of rhyolite lies in the northern part of the New Almaden ridge, having a nearly east and west strike and being about two miles long." The alta. or so-called clay referred to above, is not a substance of definite composition, though it is usually a dark or black mass, readily disting-uishable even in hand specimens from the country rock. It is simply an attrition product of the country rock and varies in composi- tion with the material from which it has been produced. Its black color is in part due to the presence of manganese. With reference to the age of the formations in the New Almaden dis- trict, Becker^ summarizes his observations in the following : "Upon highly metamorphosed rocks lie Miocene sandstones, ■uiiich were sharply folded at the Post-Miocene upheaval. They are not conformable with the lower series and contain pebbles from these older beds. In the older rocks near New Almaden Mr. Gabb found AuceUa. proving the presence of the Knoxville series. "In this district is the only mass of rhyolite thus far found in the Coast Ranges. It forms a dike nearly parallel to the line connecting the New Almaden and the Guadalupe. It is almost continuous, and I have followed it for a distance of several miles. It is certainly Post-Miocene and probably Post-Pliocene. "The New Almaden is a very extensive mine * * * Tiie ore is cinnabar, with occasional traces of native quicksilver, accompanied by pyrite and marcasite, with rare crystals of chalcopyrite. The gangue is quartz, calcite, dolomite, and magnesite. Tliese materials were deposited in shattered masses of pseudodiabase, pseudodiorite, serpentine, and sandstone. * * * "The other mines of the district contain similar ores in similar rocks. The Guada- lupe was the most productive. * * * "All the deposits of the district appear to occur along a rather simple fissure system. The main fissure is nearly parallel to the rhyolite dike at the Guadalupe. It follows the direction of the hills, the axis of which curves gradually away from the dike for a certain distance. Passing through or near the San Antonio and Enriquita. it seems to break across the ridge at the America and enters the Almaden on the strike of its two great fissures. It is near this fis.sure that new orebodies are most likely to be found. The Washington seems to be on a branch of the main fissure. "This was probably formed at the time of the rhyolite eruption, to which also I ascribe the genesis of the ore." ^Op. cit., p. 467. \ ■t-.v 3MIM lAi'R Ae3R3T A,THA8 3V11M .-^o^v^^^ am^vv •--^5 4o*'^ .•-'K. fr-^' -^ t liUl 0, '<;'*^ AV. i.V.< 1 • . .T^iHTaia ovimm ARAJD ATHAa 9l>. I -^ b. ^ ^ ; Jilj Ji tcl u f^'-Mt QUICKSILVER RESOURCES. 155 that the fissures wherein the orebodies have formed have invariably a serpentine footwall ; hence the serpentine must be considered to occur underground in a con- tinuous bodv through this entire territory and to be in places covered by overlying sandstones and shales. Southwest of Capitancillos Creek lies another parallel exposure of serpentine, contiguous to whicli the outcrops of the Costello mines are found. The Santa Teresa and Bernal mines are located in the serpentine of the Santa Teresa hills, and the North Almaden or Silver Creek mine close to those of the most northern ridge. In the latter a great part of the serpentine is very highly altered by siliciflcation, as also the sandstones, a great portion of the rocks being .iaspilites. The western slope of the adjoining Mount Diablo range is nearly e.KClusively formed of shales. "In this district the occurrence of cinnabar-carrying orebodies is clearly closely allied to that of serpentine, and as the New Almaden was the first extensively worked quicksilver mine in California, this association explains the reason why, for a con- siderable lapse of time, cinnabar ores were, in the opinion of most quicksilver miners, considered related to this rock formation. The croppings consist of a more or less weathered material having usually an ochreous color from the oxidation products of the iron sulphides, and traversed by a network of quartz seams, from a knife blade to quarter of an inch wide. Overlying the ore bodies is almost invariably found a body of clay, generally black, and containing more or less inclusions of a dark-gray sand- stone. As this ciay overlies the ore bodies it has received the name of 'alta' (Spanish for 'high' or 'upper'). At the surface this 'alta' crops as a light-gray material, resembling disintegrated sandstone, traversed by a network of very thin, yellowish- iM-own seams, often very much like a bunch of very fine roots. In places the same material can be found in the New Almaden mine several hundred feet below the surface, forming part of the 'alta.' * * * The rocks of the Franciscan series in this region show a great amount of siliciflcation. The chert beds are, however, almost entirelv unrepresented. "To" the west of the New Almaden ridge a belt of bedded sandstone is exposed. The beds are from 3 to 5 feet thick and interbedded with thinner beds of shale. * * * The country west of the New Almaden ridge and south of Capitancillos Creek, belonging to the Gabilan mountain system, consists almost exclusively of the sandstones and shales of the Franciscan series with occasionally some .Iaspilites. * * * "West of the serpentine belt which lies west of the New Almaden ridge, south of Costello's house, a small exposure of glaucophane schist was found. A body of rhyolite lies in the northern part of the New Almaden ridge, having a nearly east and west strike and being about two miles long." The alta. or so-called clay referred to above, is not a substance of delinite composition, though it is u.sually a dark or black mass, readily dLsting'uishable even in hand specimens from the country rock. It is simply an attrition product of the country rock and varies in composi- tion with the material from which it has been produced. Its black color is in part due to the presence of manganese. With reference to the age of the formations in the New Almaden dis- trict, Becker^ summarizes his observations in the following : "Upon highly metamorphosed rocks lie Miocene sandstones, which were sharply folded at the Post-Miocene upheaval. They are not conformable with the lower series and contain pebbles from these older beds. In the older rocks near New Almaden Mr. Gabb found Aucella. proving the presence of the Knoxville series. "In this district is the only mass of rhyolite thus far found in the Coast Ranges. It forms a dike nearly parallel to the line connecting the New Almaden and the Guadalupe. It is almost continuous, and I have followed it for a distance of several miles. It is certainly Post-Miocene and probably Post-Pliocene. "The New Almaden is a very extensive mine * * *_ xhe ore is cinnabar, with occasional traces of native quicksilver, accompanied by pyrite and marcasite, with rare crystals of chalcopyrite. The gangue is quartz, calcite, dolomite, and magnesite. These materials were deposited in shattered masses of pseudodiabase, pseudodiorite, serpentine, and sandstone. * * * "The other mines of the district contain similar ores in similar rocks. The Guada- lupe was the most productive. * * * "All the deposits of the district appear to occur along a rather simple fissure system. The main fissure is nearly parallel to the rhyolite dike at the Guadalupe. It follows the direction of the hills, the axis of which curves gradually away from the dike for a certain distance. Passing through or near the San Antonio and Enriquita, it seems to break across the ridge at the America and enters the Almaden on the strike of its two great fissures. It is near this fissure that new orebodies are most likely to be found. The Washington seems to be on a branch of the main fissure. "Tills was probably formed at the time of the rhyolite eruption, to which also I ascribe the genesis of the ore." ^Op. cit., p. 4 61 156 CALlFdHMA STATK .MIMXG BUREAU. Also .0 "This dike not only proves the former existence of volcanic activity in this district, but emphasizes a fundamental structural axis. The character of the metamorphic rocks .shows that the line alons which compression and upheaval took place in the early Cretaceous was about west by north, east by south. The folding- of the Tertiary rocks shows that compression was repeated in the same direction at the close of the Miocene. The position of the rhyolite dike proves that the dislocation which opened a passage for this lava again followed a similar course." Also :' "Ore deposition followed the eruption of lava. The minerals deposited and the manner of their deposition are such as in the more northerly quicksilver districts were induced by volcanic springs. Though there are now no indubitable remnants of the volcanic activity which certainly prevailed here since the beginning of the Pliocene, the analogies of the deposit, togethei- with the presence of lava of approximately the same age as the ore, make any theory of deposition excepting from hot sulphur springs improbable." There have been but two mines of con.seqnence developed in this dis- trict, the New Almaden and Gnadahipe, though there are a number of small properties which havt^ at times produced a few flasks of quick- silver. The total recorded output of quicksilver from this county is given in the following tabulation : Qi .jjcksilver Production of Santa Clara County. Year Flasks Value Year Flasks Value 1850 7,723 27,779 15,901 22,284 30,004 29,142 27,138 28,204 25,761 1,294 7,061 34,429 39,671 32,803 42,489 47,194 35,150 24,461 25,628 16,898 14,423 18,568 18,574 11,042 9,084 *20,000 16,980 27,930 30,237 24,924 36,054 .30,135 31,288 29,208 29.084 20,000 .$768,052 1,8.59,248 927.505 1,235,648 1,663,722 1,560,5.54 1,401,678 1.374,381 1,2.32,149 81,690 .378,117 1,447,7.39 1,442.041 1,380.,3.50 1,9.50,245 2.166,205 1.867.519 1.122,760 1,176,.325 775,618 827,592 1.171,641 1,224..584 887,004 995.4.55 *1, 098,000 1,428,867 1.228 920 1.127;S40 820,000 1,076,212 934,185 933.321 824,. 54 2 8.36,165 610,000 1885 21,400 18.000 20.000 18.000 13,100 12.000 8,200 5,563 6,614 7.235 7.050 6,222 4,700 5,875 4,435 5,145 5.220 5.869 5,603 t3.889 2.693 2,592 2,518 2.460 3,747 4,038 7,533 8,695 3,709 2.407 4.386 4.016 5.921 $658,050 639 000 1851 1886 1852 1887 847 600 1853 1888 765 0(10 1854 1889 .589 500 1855 ... 1890 630 (¥10 1856 1891 371 105 1857 .. _ 1892 1893 226 470 18.58 243 064 1859 1894 222.169 1860 1895 ... 253.8(10 1861 1896 •'11 570 1862 1897 169.200 1863 1898 2.35.000 1864 1899 •. _ 186.270 1865 190(1 241 073 1866 1901 •"'36 608 1867 1902 ■254.260 1868 1903 . 233.130 00 19114 148,1(13 1870 1905 95.968 1871 1906 94.608 1872 1907 96,086 1873 1908 . 103.984 187-1 19(19 191(1 1.58 490 182.719 187.- 1911 346..593 1876 ..... 1912 1913 1914 365 538 1877 ... 149.213 1878 118.063 1879 1915 376.319 188(1 1916 375.496 1881 .. ... 1917 639.-594 1882 'rotalfs 1883 1,127,380 $.52,299,517 1884 ♦Estimated production of Guadalupe Mine previous to 1875. + Flasks of 7.-) pounds since June, 1904: of 7G>. pounds previously. '■Idem, p. .314. 'Idem, p. 328. QUICKSILVER RESOURCES. 157 Bernal Mine. Mrs. Yynacio Beiiial, owner, Edenvale. It is 10 niile.s southeast of San Jose, on the east slope of the Santa Teresa hills, at an elevation of about 450 feet. A tunnel, over 200' long, was driven along a ehiy gonge and serpentine contact, many years ago ; but failed to encounter any important orebody, so it was abandoned. No work has been done in recent years. Bibl. : Cal. State ^Min. Bur., Bull. 27, p. 171 ; Chapter rep. bien. period, 1917-1918, in prep. Bowie Prospect, New Almaden district. Circle B. Mining Company, owner. Prospect only. Idle. Brainard Prospect. This is on patented property owned by Mrs. M. D. Brainard et al. of San Jose, situated south of the Guadalupe mine, and west of the northern end of the New Almaden lands. There is an old adit in Avhich it is stated some cinnabar-bearing material was cut, Init therr has been no work done in recent years. Comstock Mine. T. H. French, OAvner, Lone Tree via Hollister. It is in the extreme southeastern corner of Santa Clara County, in Sec. 19, T. 11 S., R. 7 E., M. D. M., and in the Stayton district most of which lies in San Benito and is described herein under that county. The Comstock mine is located on the only surface exposure of serpen- tine found in the Stayton district. Abandolied some years ago. Bibl. : Cal. State Min. Bur., Report XII, p. 367 ; Bull. 27, p. 172 ; Chapter rep. bien. period, 1917—1918, in prep. Min. Res. W. of Rocky Mts., 1875, p. 14. Costello Mine. M. Costello, owner. New Almaden. It is about 1^ miles by road southeast of the Guadalupe mine, on the hillside above Los Capitancillos Creek at an elevation of about 1000'. It is a pros- pect only and no ore was found in place. It has been idle for a number of years. Bibl.: Cal. State Mix. Bur., Bull. 27, p. 172; Chapter rep. bien. period, 1917-1918. Guadalupe Mine. New Guadalupe Mining Co., owner; Hugh C. Davey, president ; John L. Stubbs, vice-president ; Chas. W. Aby, treas- urer ; Route A, Los Gatos. This property, covering a territory of 2500 acres, is situated 10 miles south of San Jose on the west slope of New Almaden Ridge, and adjoins the land of the New Almaden company on the northwest. The mine was discovered in the early 50 's and is said to have produced 20,000 flasks of quicksilver up to 1875, when it became the property of the Guadalupe ^Mining Company. This com- pany erected furnaces and made many surface improvements. In 1886 the mine was shut down due to litigation, remaining idle until 1900 3 O J3 3 c 3 O u o c a 00 Q. 3 3 o o 2 o QUICKSILVER RESOURCES. 159 when H. C. Davey. one of the present owners, organized the Century Alining Company. The old furnaces were remodeled, the mine unwatered, and operations resumed, since which time it has been an important and continuous producer. The total recorded output has been 105.772 tiasks to the end of 1917. The mine was first worked by a vertical shaft, 625' deep, sunk on the south side of. and near the bottom of Capitancillos or Guadalupe Creek. It was very difficult to keep the surface w^ater out of this .shaft during the wet seasons, and it was finally abandoned. A 700-foot incline, which is now the main working' shaft, was then sunk on the opposite side of the creek on the dip of the vein (see Photo No. 34). It has 3 compartments down to 180' on the incline (where it connects with Xo. 1 Tunnel, whose portal is just above the creek bed), and 2 com- partments below that. There are many miles of underground work- ings in the Guadalupe. Several shallow shafts and drifts have been driven on different outcrops about the property, but mining is now^ eon- fined to the main workings. From the plan of the old workings, it appears that the orebody developed by the vertical shaft on the south side of the creek had a northwest strike and southwest dip. The second level, 300' below the collar of the vertical shaft, connects with the incline shaft on the oppo- site bank of the creek. From the sixth level (625') of the vertical shaft an incline winze was sunk from which the seventh, eighth and ninth levels w^re driven ; but ore Avas developed only on the seventh .and eighth levels. The ore of the Guadalupe mine is similar in appear- ance to that of the north-end New Almaden ground, being in part at least a silicified serpentine with cinnabar. There is some associated pyrite. "When visited by the writer in September. 1917, the bed of the creek was being replaced by a concrete flume, 740' long and 55' wide, with side walls 9' high, to carry the stream over the portions of the old mine beneath. There is a 1' high cross-wall CA^ery 100' to hold the gravel and protect the flume floor from excessive wear. With this improvement in service, it is intended to un-water and again open up the old workings. Electric power will be used. Equipment includes electric hoi.sts. air compressors and machine drills. The reduction plant consists of 2 coarse-ore furnaces of 18 tons capacity each, and 2 fine-ore furnaces of 30 tons capacity each, all oil-burning, and modeled after the Davey patents. The ore is broken to cobble size and sorted by hand in the mine, the waste being partly used to fill old stopes. At the surface, the ore is screened, and then trammed by mule-drawn trains to the fine and coarse-ore furnaces respectively. The fine ore is passed through a rotary drier, 29' long x 28" diam.. lined Avith one row of fire-brick, and driven by a 3 h. p. electric motor at 2 r. p. m. The discharge is ]60 CALIFORNIA :>TATE MINING BUREAU. directly into the feed end of the fine-ore furuaee, in a sealed compart- ment to prevent escape of any mercury vapors that might be present. A concentrating plant of 50 tons daily capacity was built, and started operating in February, 1917, handling material from the old mine dumps. Crushing is done in a ball mill with 20-m&sh screen. After classification, the fine pulp goes to a Deister table, and the sand to two WiWeys. The plant is driven by a 25 h. p. semi-Diesel oil engine. The concentrates are said to assay 8%— 10% mercury, and are reduced in the fine-ore furnaces. In September, 1917, there were 75 men employed, 25 of whom were underground. Bibl. : Cal. State Mm. Bur., Keports, VIII, p. 542 ; XIII, p. 600 ; Bull. 27, p. 173; Chapter rep. bien. period, 1917-1918 in prep. MiN. Res. W. of Rocky ^Its., 1875, p. 13 ; 1876 ; p. 20. U. S. G. S., Mon. XIII, p. 326. Hillsdale m- San Juan BaUtista Mine (one time called Chapman; also Chaboyaj. Elizabeth Kohrs, owner, Hillsdale via San Jose, R. F. D. It is about 2 miles southeast of San Jose on the east slope of the San Juan Bautista Hills, and within one-half mile of a street-car line. These hills, an isolated group, composed of metamorphic rocks, largely serpentine, rise to a height of only a few hundred feet above the valley, and are a northward continuation of the Santa Teresa Range. The mine is said to have been discovered in 1847 and worked to 1861 by ^Mexicans, subsequently becoming the property of a Mr. Chapman who worked it up to 1874. In the spring of 1871, production was at the rate of 30-40 flasks of quicksilver per month. ^ It lay idle from 1874 until 1892, when it was reopened by R. H. Harper of San Jose, and worked spasmodically in a small way up to 1907. In 1915, under the name of New Discovery Quicksilver Company, a lease and bond was taken and a few flasks of quicksilver produced ; but little work was done underground, and the lease forfeited. R. H. Harper was recently reported to be negotiating for the purchase of the property. There are said to be over 4,000 feet of underground workings, but most of the tunnels are now inaccessible, being caved. The reduction phint consists of two 12-pipe retorts, evidently built in later years, as they are in good condition. Bibl.: Cal. State IMin. Bur., Report XIII, p. 600; Bull. 27. p. 174; Rep. bien. period, ]917_191S. in prep. (Jeol. Surv. oi Cal., Geol. vol. 2, pp. 112-113. New Almaden Mine (originally Chaboya; tlien Santa Clara). The Quicksilver Alining Company, owner; New Almaden Company. Inc.. 'Ooodvp.nr. AV. A., Report on examination of quick.silvor mines in California: Gcol. Siirv. of Cal.. Cit-ol. vol. 2, pp. 112-113. 1882. 1^ ^ 1 T 1 n T." *. ' T T T T-' *-» T-» T-. ^ axAjq tO 31/11 M H3aAMJA W31/1 JA^.OD A51AJD ATMA8 VIGI .rpLiJeb es lUH sniM ^O ron //■X u *"4 I sfner. Wr '•FBi-sfnpr. Wm.. Quicksilver resources of Calil'ornia : Cal. State Min Bur p. lio. 1003. 11— 3S,>tO 161 has. A. ger, 57 } acres, le New to the 5 prop- being 1845, ed) it ia into ^'orbeS worked were ipany |uiek- Hiitt- com- total 1917, dur- ished Idria , the ■eave- hich nine cans e of ;'s of iles, itest oint 300' lere s at aft, rry the Bull. 27, PLATE XIX. NEW ALMADEN MINE SANTA CLARA CO.. CAL. SHOWING PRINCIPAL STORES. LEVELS AND DUMPS 1917 l ; . -A : j^ ' * i COMPILED FROM t I sroPES COMPANY necoRos OUMPS NOTE Elevations are rrfinus (-) and refer to outcrop at summit of Mine Hill as datum. Aetompof„jinff atjlMt,n Nt> 7S. Ca'iforr..o State M.^:x^ Buree 88040 p. im QUICKSILVER RESOURCES. 161 Icssei'; Geo. II. Srxtoii, pivsideiit, 45 Broadway, New York; Chas. A. Frank, secretary and treasurer; Edmund Juessen, general manager, 57 Post Street, San Francisco. This property, covering over 8000 acres, lies from 8 to 13 miles east of south from San Jose' along the New Alniaden Ridge, and was at one time second only in production to the famou.s Almadeu mine in Spain, after which it was named. This prop- erty is the oldest known quicksilver mine in the United States, being first worked in T824 by Antonio Suiiol and Luis Chaboya. In 1845, Andreas Castillero, a Mexican army officer, 'denounced' (located) it under the name of Santa Clara. After the admission of California into the Union, Castillero and associates leased the mine to Barron Forbes & Co.. who changed the name to New Almaden. It has been worked continuously since 1845, but the greatest surface improvements were made after it became the property of The Quicksilver Mining Company in 1864. ]\Iauy important practices and appliances in the metallurgy of quick- silver had their beginning here, including the development of the Hiitt- ner-Seott tine-ore furnace in 1875-1876. The present operating com- pany look over the property under a lease and bond in 1915. The total production has been 1,021,183 flasks of quicksilver, to the end of 1917, surpassed by only one mine in the world (Almaden Mine, Spain) dur- ing the period in which New Almaden has been operating. Published records show that this total, however, has been exceeded by the Idria mine. Austria, and the Santa Barbara mine, Huancavelica, Peru, the bulk of whose production was made prior to 1850; in fact, Huancave- lica has yielded but little quicksilver since 1800. GEOLOGY AND MINE V^^ORKINGS. The New Almaden property really contains three mines, all of which are located on the same mineral belt: the great New Almaden mine proper, the Enriquita, and the Senator or El Senador as the Mexicans named it (also referred to as the North Line Mine). A distance of nearly 4 miles separates the first and the last-named. The workings of the main New Almaden mine, cover a territory of about 2^ square miles, wliich i.s exclusive of the Enriquita and Senator; and their greatest depth is 2450 feet below the top of ^line Hill, which is the datum point for all underground workings. The elevation of Mine Hill is 1600' above sea-level. In this territory 18 shafts have been sunk, and there are nearly 100 miles of underground excavations, much of which is at present inaccessible. Forstner states^ that in 1903, the Victoria shaft, a short distance to the southwest of the Randol shaft, and the Harry shaft, on the southeast slope of ]Mine Hill (see Plate XIX) were the 'Forstner. Wm., Quicksilver resources of California: Gal. State Min. Bur., Bull. 27, p. 17.5. 1903. 11-3S.>40 160 n \T Ti.'MiJVl \ 1. QUICKSILVER RESOURCES. 161 Icssrc ; (u'O. 11. Sexton, president, 45 Broadway, New York; Cha.s. A. Frank, secretary and treasurer ; Edmund Juessen, general manager, 57 Post Street, San Francisco. This property', covering over 8000 acres, lies from 8 to 13 miles east of south from San Jose' along the New Almaden Ridge, and was at one time second only in production to the famous Almaden mine in Spain, after which it was named. This prop- erty is the oldest known quicksilver mine in the United States, being first worked in 1824 by Antonio Suiiol and Luis Chaboya. In 1845, Andreas Castillero, a Mexican army officer, 'denounced' (located) it under the name of Santa Clara. After the admission of California into the Union, Castillero and associates leased the mine to Barron Forbes & Co.. who changed the name to New Almaden. It has been worked continuously since 1845, but the greatest surface improvements were made after it became the property of The Quicksilver Mining Company in 1864. k ]\Iany important practices and appliances in the metallurgy of quick- silver had their beginning here, including the development of the Hiitt- uer-Scott fine-ore furnace in 1875-1876. The present operating com- pany took over the property under a lease and bond in 1915. The total production has been 1,021,183 flasks of quicksilver, to the end of 1917, surpassed by only one mine in the world (Almaden Mine, Spain) dur- ing the period in which New Almaden has been operating. Published records show that this total, however, has been exceeded by the Idria mine, Austria, and the Santa Barbara mine, Huancavelica, Peru, the bulk of whose production was made prior to 1850 ; in fact, Huancave- lica has yielded but little quicksilver since 1800. GEOLOGY AND MINE WORKINGS. The New Almaden property really contains three mines, all of which are located on the same mineral belt : the great New Almaden mine proper, the Enriquita, and the Senator or El Senador as the Mexicans named it (also referred to as the North Line Mine). A di.stance of nearly 4 miles separates the first and the last-named. The workings of the main New Almaden mine, cover a territory of about 2^ square miles, which is exclusive of the Enriquita and Senator; and their gTeatest depth is 2450 feet below the top of Mine Hill, which is the datum point for all underground workings. The elevation of Mine Hill is 1600' above sea-level. In this territory 18 shafts have been sunk, and there are nearly 100 miles of underground excavations, much of which is at present inaccessible. Forstner states^ that in 1903, the Victoria shaft, a short distance to the southwest of the Randol shaft, and the Harrv shaft, on the southeast slope of ]\Iine Hill (see Plate XIX) were the 'Forstner. W'm., Quicksilver resources of California : Cal. State Min. Bur., Bull. 27, p. 175. 1903. 11— 3S540 162 CALIFORNIA STATE MINING BUREAU. only two shafts then in operation. The deepest workings then being followed were on the 1000' level, as below 1300' the mine was filled with water. Since that time, most of the work has been done through the Harry shaft and the Day tunnel, and more recenth* at the Senator mine. Geology. The geology of the New Almaden mine has been studied and described in considerable detail by a number of authors, the most important of whom was Becker. He states r "Tlie ores * * * are composed of the usual association of minerals : cinnabar (sometimes accompanied by a little native mercury), pyrite, quartz, calcite, and dolo- mite, and more or less closely associated masses of bituminous matter. Accompany- ing the deposits is a small amount of chalcedony or opal, usually black in color, but this substance is much less abundant here than in the greater part of the northern mines. Dolomite is more prevalent as a gangue mineral here than in most quicksilver districts * * *_ "The rocks associated with cinnabar in this district include every variety of the metamorphic series. Where the rock happens to be a permeable sandstone, impreg- nations have resulted. Elsewhere the ore seems to occur exclusively in crevices in the rock * * * j ^as unable to perceive any indication that ore had been deposited by substitution or that the rock had influenced the deposition of ore by its chemical properties. Ore is found Mntli nearly equal frequency in contact with various rocks and the existence of fissures appears to have been the necessary and sufficient condition for the deposition of cinnabar and gangue minerals. * * * "The ore in the New Almaden mine seems never to occur except close to evidences of faulting. This evidence consists in the presence of layers of attrition products, so-called clays, full of slickensides and of fragments of rocks more or less rounded by attrition. These layers of clay usually occur on the hanging side of deposits and are known to t!ie miners as altas, the Spanisli term for hanging-walls. The clays are impermeable to solutions and the ore usually forms on their lower side, as if the cinnabar had ascended and been arrested by the altas. * * * "While the evidence of the existence of a fissure system is. if possible, more abundant in the New Almaden mine tlian in most quicksilver deposits of the Pacific Slope, the deposits themselves are of various types. The commonest is the reticulated mass, or stockworks, consisting of irregular bodies of broken rock into which solutions of cinnabar and gangue minerals have filtered, cementing the fragments together with ore. Where the disturbance has been less extensive and irregular, clean- cut fissures may sometimes be seen filled with ore, and these can only be classified as veins, though they are not persistent. * * * "Certain features must be common to the ore bodies taken singly and to the ore- bearing ground as a whole. It would be impossible to suppose that each stockwork has an independent fissure system, and a mere glance at the mine map shows that a connection between them exists. It is also a historical fact that the thin seams of ore * * * ]iave led from one ore chamber to another. * * * "The distribution of serpentine, the average strike of the metamorphic strata, the compression of the Miocene beds, the position of the rhyolite dike, and the trend of the range, in short the whole structural geology of the region shows that the fundamental axis of disturbance must have a direction which is approximately north- west and southeast." Also :^ "Considered in detail, the ore bodies are stockworks : but they are arranged along definite fissures and tlio deposits as a whole have a vein-like cliaracter and an.swer to the 'cliambered veins' defined in a subsequent paragraph. The workings have developed two main fissures. One of these dips from the smface at a high angle and in a nearly straiglit line. Tlie other strikes in nearly the same direction as tlie first, dips steeply from the .surface, then flattens and appi'o.aches tlie first fissure rapidly, again becomes very steep, and in the lowest woi-kings almost coincides witli the first. In vertical cross-section the two fissures form a figin-e i-esembling a V. Tlie great ore bodies are distributed along these two fissuies. making irregiflarly into the walls. The wedge between tlie fissures also contains ore Vtodies." Mine Hill Workings. The surface and woi-kiugs of the New Alin;ideii mine have been minutely surveyed ;ind tlie data carefully preserved by the officers of the Quicksilver Alining Coiiii);iiiy in the form of a large, detailed, ^Becker, G. V.. Quicksilver deposits i)f the Pacific Slope: U. S. Geol. Surv., Moii. XTTI. pp. 3H et seq, 1888. "Op. rit.. p. 467. QUICKSILVER RESOURCES. 163 colored map which hangs in a specially-constructed fireproof draught- ing room, adjoining the office at the Hacienda. An excellent repro- duction of this map, up to the date of its publication, 1888, accom- panies Becker's report.* The map herewith (Plate XIX) was com- piled from the company's records and is reproduced herewith by courtesy of Mr. Edmund Juessen, general manager. The principal dumps are shown in brown with the surface contour lines. The prin- cipal orebodies extracted since Becker's publication of the map, are indicated by: 1. The N-S line of stopes to the west of and nearest the Harry shaft. 2. The line of stopes lying approximately at right angles across the northwestern end of the older stopes, and extending south- westerly from the 'mouth of Randol tunnel.' 3. Portions of the stopes south of the Cora Blanca shaft. The ore deposits are limited on their hanging-wall side by the alta, which being an impermeable layer prevented the passage Of water cir- culation. According to Forstner,^ the footwall side is persistently ser- pentine, from which it is concluded that the serpentine, or rather the intrusive peridotite which has altered to serpentine, is the cause of the fracturing of the other rock strata. "The fracturing has taken place on both sides of tlie serpentine, which apparently can not be considered otherwise than as an intrusive body having uplifted the roclis of tlie Frixnciscan series. "The ore bodies form principally in tliose parts of the zones where the dip of the 'alta' is very flat * * *. The contact of tlie alta with the underlying vein filling, and where this is missing with the serpentine, is very tortuous in botli directions, vertically and horizontally, so that in the gangways, which * * * follow this contact, it is an exception to find a straiglit line of any length. The stopes are locally called 'labores.' The material whicli fills the zones of fracturing and wherein in places cinnabar forms, is generally rather hard and siliceous, traversed by a , network of seams of quartz and dolomite, showing repeated fissuring and filling con- taining some inclusions of serpentine, the cinnabar forming principally in connection with the seams. In places the vein-filling has more of an ochreous character, the matrix being more or less leached out, leaving only the network of seams intact. * * * "The general character of the vein-filling indicates that, as in most of the other quicksilver deposits in the State, tlie deposition of cinnabar has been associated with the process of siliciflcation, which characterizes the alteration of the rocks of the Franciscan series. "The general direction of the seams in the vein-fllling is not parallel to the line of contact with tlie alta. * * * jj^ ^l^g upper workings the part nearest to the alta is seldom the richest, the cinnabar forming more plentifully at from 5' to 8' below the alta, while in the lower workings the richest ore is invariably close to the alta. "The contact between the alta and the vein-filling is very sharply marked, but there is a gradual change of the above-described vein-fllling into the material of the serpentine foot-wall, tlie vein material gradually carrying more serpentine, until it has entirely changed into the latter. Tlie hanging-wall is a shale, judging from surface exposures. Underground, no crosscut through tlie alta to the hanging-wall was seen." Recent work. When visited by the writer in September, 1917, some ore was being broken in stopes connected with the Day tunnel, and which it was intended to burn in the coarse-ore furnaces at the Hacienda. Plans were being made to drive a connection on the 800' level, from the Santa Rosa drift near the main shaft, to Deep Gulch tunnel. This will per- mit of tramming around the hill to the Hacienda furnaces, a distance of about ^ mile, or about one-half that now traveled for delivery from *0p. cit.. Atlas Sheet IX. ^Op. cit., p. 178. ]l>4 CALIFORNIA STATE -AIIXIXG BUREAU. the D;iy tnnncl. Eqnij)ni('nt ;it the inoulli of the l)a>" Tunnel includes an Inuersoll-Kand duplex compressor. I()"xl4" and 1ip several feet aliove the level of the throat, thus giving an auxiliary ore-bin ,ind providing an automatic furnace-feed. There are eiglit new condensing chambeis connected with this furnace, arranged in a double row. The first cliamber in each row is of concrete, and the other three are of tongue and groove redwood, built rectangidar. A 3-foot redwood-stave flue was being put in to connect the last of tliis series of condensers to the first circular wooden condenser of tlie HerreschofY sei-ies. Crude oil is used for fuel. "See pp. 250-253, post. ""Ijanders, W. IT., The smelting of mercury ores: Eng. & Min. Jour., vol. 102, p. 634, Oct. 7, 1916. QUICKSILVER RESOURCES. 167 Between the condensers and the outlet stack is a second Cottrell fume- precipitator (called the 'cold treater') to throw do^^^l any remaining mercury 'mist' that may still be in the gas flow. It is stated that a little quicksilver is obtained in this cold treater. For the Cottrell electric precipitators, the incoming line current of 440 volts is trans- formed up to 50,000 volts for the 'hot treater', and to 100,000 volts for the 'cold treater'. During 1916 and a part of 1917, concentration plants including flo- tation units were in operation at the Day tunnel and at the Senator mine, but both had been dismantled just previous to the writer's visit in September, 1917. These plants are described in detail elsewhere herein." in the section under Metallurgy. There is little or no mining timber available in the vicinity of these mines. Sawed timber is brought in by the railroad from outside points^ Fuel oil is used at the furnaces. In September, 1917, a total of 105 men were employed, including 60 underground, and 6 at the Senator furnace plant. Bibl. : Note— The New Almaden mine and plant have been described by so many writers, that only the principal references are here given. Others will be found in the Bibliography in Part III. of this bulletin. Cal State Min. Bur., Reports I, pp. 26, 27; IV, pp. 336 et al; YIII, pp. 541-542; X, pp. 604-606; XI, pp. 374-375; XII, pp. 367-370; XIII, pp. 600-601; Bull. 27, pp. 174-186; Chapter rep. bien. period 1917-1918, in prep. U. S. G. S., Mon. XIII, pp. 8, 310-330, 467; Bull. 78, pp. 80-83; Min. Res. 1883-1915 inc. :\Iin. Res. W. of Rocky Mts., 1867, pp. 170-178; 1874, pp. 33, 380, 540; 1875, p. 13; 1876, pp. 4-18, 20. Miv & Sci. Press, vol. 84, pp. 393^04, 1902: vol. 87, p. 201, 1903; vol. 100, pp. 15-16, 446-447; Feb. 16, 1916, pp. 282-284. Eng. & MiN. Jour., vol. 34, pp. 185-186, 334, 1882 ; vol. 91, p. 85, 1911; vol. 102, p. 630, 1916. Geol. Surv. of Cal., Geol. vol. I, p. 68;'vol. II, pp. 91-110, 122. Santa Teresa Mine. Enos Fontis, of Edenvale, owner. This prop- erty is 8 miles southeast of San Jose on the east slope of the Santa Teresa hills. It was developed by the Santa Teresa Quicksilver :Min- ing Company, of which R. H. Harper of San Jose was superintendent. A°40-ton Scott furnace was erected, and several tunnels driven into the hill to cut the vein. The country rock is serpentine, and the ledge mat- ter an alteration product of serpentine through silicification, carrying a low percentage of cinnabar. After working a few years, without "See pp. 343-344, post. 168 CALIFORNIA statf: mixing bureau. encountering' any orebodies of sufficient size or riehness to warrant their further exploitation, the mine was abandoned; and is still idle. Bibl.: Cal. State Min. Bur., Bull. 27. p. 186: CMi;i[)t('r rep. bien. period, 1917-1918, in prep. Silver Creek Mine (North Almaden). A. R. Bradford et al., owners, 770 E. St. John St., San Jose. This property, formerly known as the North Almaden mine, is 12 miles by road southeast of San Jose, on the east side of Silver Creek. A large body of serpentine containing cin- nabar was found in Silver Creek gulch, overlying Knoxville gravels. This detached body was evidently due to a great landslide which is plainly visible about the works. It was approximately 1000' in length, 300' wide, 60' in thickness, and was exhausted in a few years, produc- ing about .$60,000 worth of quicksilver. Occasional prospecting has been carried on since, but no important ledge has been found in {ilace. The property is equipped with a 20-ton Scott furnace and a pipe retort. Bibl.: Cal. State Mm. Bur., Reports XII, p. 367; XIII, p. 600; Bui. 27, pp. 187, 235, 238; Chapter rep. bien. period, 1917-1918, in prep. Wright Mine. Mrs. A. Rodgers, owner, San Francisco. It is 3 miles south of the New Almaden Hacienda, on Llagas Creek, and is said to have produced some high-grade ore many years ago. It is hardly more than a prospect, and has had but little deevlopmcnt work done on it. Idle. Bibl.: Cal. State Min. Bur., Reports XII, p. 370; XIII, p. 600; Bull. 27, p. 187; Chapter rep. bien. period, 1917-191S. in prep. SHASTA COUNTY. Clover Creek Mine (formerly Clover Creek Cinnabar Company). N. B. Frisbie and F. P. Primm, owners. Redding. It is on patented ground in Sees. 4 and 5, T. 32 N., R. 1 W., M. 1). M., 30 miles north- east of Redding, and was discovered about 1898. A mineralized zone containing cinnabar is reported, 100' wide, striking northwest and dip- ping 30°, having been treated for one-quarter mile in length. Devel- opments consist of several shallow shafts the deepest of which is ;")()'. and some drifts. No commercial pi-oduction of (|uicksilvt'r has as yd been reported. Thci-c is j^lenty of wood and watci- at haml. 'I'he owner states that the property has been twice Ijonded to St. Louis parties; but that they spent most of their money on salai-ies and office rent instead of mine development. Bibl.: Cal. State Mis. Bur., Bull. 27. u. 196. QUICKSILVER RESOURCES. 169 SISKIYOU COUNTY. ^ Several occurrences of cinnabar have been noted in the northern part of Siskiyou County in the vicinity of Oak Bar on the Klamath River, northwest from Yreka. Some development work has been done at intervals, and the records indicate a small commercial production of quicksilver some years ago. There is prospect of further output the coming season. 1918, in at least one property. Cinnabar is often found in the sluice boxes of the hydraulic mines of this district. Minnehaha Mine (also known as Barton-Lange Mine). H. J. Barton, owner, Oak Bar. It is in Sec. 15, T. 46 N., R. 10 W., M. D. M., on the Klamath River near the mouth of Horse Creek, about 5 miles west of Oak Bar. Patented, 20 acres. Discovered in 1878. The cinnabar mineralized zone is in an area of metamorphic rocks stated to be in contact with granite. The development work done so far has all been superficial, consisting of open-cuts and ground sluicing. About 1916 some cinnabar concentrate was obtained by ground shiicing, about enough it is stated to yield 4 flasks of quicksilver, but it has not yet been treated as there is no reduction equipment at the property. Small amounts of the translucent red, cinnabar crystals obtained here by sluicing Avith pole riffles were formerly sold to the Chinese for medicinal purposes. Bibl.: Cal. State Min. Bur., Reports XIII, p. 602; XIV, p. 870; Bull. 27, p. 196 ; Chapter rep. bien. period 1913-1914, p. 126. Mt. Shasta Cinnabar Mine (also referred to as the Cowgill Mine; formerly owned by the Ivanhoe Quicksilver Mining Company). Mer- cury Company of America, owner; Eugene C. Belknap, manager, Yreka. This group of claims is in Sec. 34, T. 48 N., R. 9 W., M. D. M., on the west fork of Beaver Creek, 10 miles in an air-line northwest of Gottville, and adjoining Clarretson Springs. It is 12 miles by trail, or 24 miles by a steep, difficult wagon-road from Gottville, and about 3 miles south of the California-Oregon state line. Gottville is 20 miles by a good county road down the Klamath River from the Southern Pacific railroad at Hornbrook. Locations have been made by this com- pany on other quicksilver prospects in nearby sections, and an option taken on the Herzog-^Iorgan claims in Sees. 24 and 25, T. 47 N., R. 8 W., on Empire Creek. Some work was done years ago on this prop- erty by the Siskiyou Quicksilver Mining Company, who built a 10-ton furnace, and are stated to have produced a few flasks of quicksilver. The present owners have recently completed a 12-pipe Johnson-^IcKay retort. The cinnabar, which is coarsely crystalline, occurs in a wide mineral- ized zone with sandstone and metamorphic rocks some of whicli are 170 CALIFORNIA STATE MINING BUREAU. schistose. Belknap states that screen tests made on the surface soil in this mineralized zone showed that after passing through a j" screen, 72.3% of the material will pass a 20-mesh screen and assays 0.013% mercury. Owing to the fact that apparently such a large percentage of low-grade material can be gotten rid of by simply screening, the values being mainly in the particles coarser than 20-mesh, it is pro- posed to adopt such a method of ore dressing. A scraper and cable equipment Mill be installed for excavating the ore, which will be passed through a revolving screen with a stream of water, as it will be simpler to carry the tailings away in a launder than to transport it dry. The oversize, or concentrate, will then be dried and retorted. It is expected by this method to test out the ground. The soil occurs up to a depth of 60 feet. There is plenty of water at hand both for power and mill- ing purposes. Bibl. : Cal. State Min. Bur., Reports XII, p. 370 ; XIII. p. G02 ; XIY, p. 870; Bull. 27. p. 196; Chapter rep. bien. period, 1913- 1914, p. 126. QUICKSILVER RESOURCES. 171 SOLANO COUNTY. The quicksilver mines of Solano County are situated on the prom- inent ridge known as Sulphur Springs IMountain from five to seven miles northeast of Vallejo. This ridge trends northwest, and has been the locus of volcanic or other igneous activity and consequent meta- morphism. The Vallejo hot sulphur springs are on the western side of this ridge, about midway, being a mile and a half south of the St. John's mine, and about a mile northwest from the Brownlie and Hast- ings properties. The St. John's mine is at the northern end of the ridge, the culminating point of which is Mt. St. John, elevation 1110' (U. S. G. S.). The Brownlie and Hastings w^orkings are on opposite sides of the ridge, about three miles southeast from the St. John's mine which has been the only important producer of quicksilver in Solano County. The recorded production of quicksilver in Solano County is shown in the accompanying tabulation: Quicksilver Production of Solano County. Tear Flasks Value Year Flasks Value 1873 1,800 1,900 2,100 1,683 1,463 802 1,290 492 $144,594 199,842 176,715 74,052 54,570 26,386 38,507 15,252 1906 1907 528 640 764 $19,272 1874 24,422 1875 --- -. . 1908 a3,294 1876 1909 1877 1910 1878 _ 1911 1879 1912 1880 1913 1881 1914 . - - - 320 466 660 554 15,680 1901 -- 1915 35.000 1902 42 100 -377 542 1,890 4,100 15,080 18,518 1916 61,710 1903 1917 . 52,765 1904 1905 Totals 16,523 $1,011,649 *Flaslcs of 75 pounds since .June, 1004; of 76^ pounds previously. Brownlie Mine. John Brownlie Estate, owner, Vallejo. It is on patented ground, on the western side of Sulphur Springs ]\Iountain, about -i mile due west from the Hastings mine, and 4 miles north of east from Vallejo. It is in Sec. 10, T. 3 N., R. 3 W., M. D. M. ; eleva- tion 600' (U. S. G. S.). Some work was done on this property in the '70 's, but it consi-sted only of .shallow, surface cuts. An option has recently been given by the owners to parties who may soon start explor- ation work. Bibl.: Cal. State IMix. Bur., Reports VIII, p. 631; XIII. p. 599. Hastings Mine. Hastings Estate, owner; Chas. Wendell Hunt, agent ; White Investment Company, lessee, G. A. Newhall et al.. New- hall Building, #206 California St., San Francisco; John Andrews, 172 CALIKOKMA STATE MINING BUREAU. superintendent at the mine. It is in Sec. 11, T. 3 N., R. 3 W., M. D. I\r.. on the eastern side of Sulphur Springs Mountain. 7 miles by road north of Benicia, and 4j miles in an air-line, north of east from Val- le.jo. The lea.se covers the mineral rights on 600 acres of the Suscol Raneho, also known as the D. N. Hastings Sulphur Spring Valley Kanch. The property was originally operated in the '70 's by a series of shallow surface cuts, and 'coyote holes'. Some work is reported to have been done about 1904-1905, but apparent!}^ no production of metal was then made. A small yield was reported in 1916. In P^eb- ruary, 1917, the mine was reopened by A. G. Kullberg, et al., under lease; and a fair output of quicksilver made, the lease being trans- ferred to the present operators in November. The mineralization occurs in a brecciated zone about •l:0'-60' wide, striking W. of N., and dipping 70^-80°' W. There is an igneous mass (dike?) on the hanging-wall side, which resembles the granular, meta- andesite dikes of the St. John's mine and which w^ere formerly described as 'metamorphic sandstone.' The ore occurs in the fractures of the brecciated rocks. An indurated shale or chert, and opaline material were noted. Both cinnabar and metacinnabarite are present, being mainly crystalline, with little or no pyrite apparent. The main tunnel cuts the vein at 950' in, and continues another 150' to the igneous formation noted above. This gives a depth of 112' below the outcrop. It is stated that on the surface some ore has also been found on the other (west) side of this igneous rock. In fact, the Brownlie mine is on the west side of it, ^ mile distant. There is another adit, 20' above the main level. There is one slope 30' high x 15' long x 10' wide, and another 40'x20'x20', besides other smaller ones. The mine car dumps into a small ore-bin with a grizzly, at the portal of the main adit, from which point the ore is hauled in a dump cart, about 200 yards down the hill to the furnaces. Reduction equipment consists of a small, Neate coarse-ore furnace of about 6 tons eapacit.y, and a bank of 3 retorts similar to a large 'D' retort but having a rectangular cross-section, instead of an arched top. They have a capacity of li tons each per day. They are arranged to use oil, but when visited l)y the writer (IMarch, 1918), were being fired by coke, because of inability to get oil for a time. The Neate coarse- ore furnace is not now utilized. There are 4 brick condensers, with 3 chambers, each. The ore being treated was yielding 1.72% mercury. Thci'c were 9 men employed. Bibl.: Cai. State Mik. Bur., Report XI II, p. 599. St. John's Mine (originally referred to as the Vallejo). St. John's Mines Company, owner; Clifford 0. Deiuiis, president and manager, X'allcjo; C. F. Colmai'. secretary, ^[(u-hanies Institute Building. San , W^j MAP ST. JOHNS QUIC NE VALLEJO.SOl SCALE ( zoo 400 1 I ' >^=> G£OLOGy By ost AccomponL//nff Bij//6 PLATE XX. IVH/ TE A RE AS - i/AfS TUD'ED Accomponi//nff Bu//etinNo. 78, Co/ifom/o State Mjning Bureau SERPE/^ TiNE E R0>- WESTON, oei QUICKSILVER RESOURCES. 173 Francisco. It is in See. 33, T. 4 N., R. 3 W., M. D. M., 6 miles north- east from A'alle.jo, with an e.xcellent oiled road to within 1 mile of the furnaces. The mine is at the northern end of the Sulphur Springs Mountain ridge. Cinnal)ar was first found here in 1852 by John Neate, who carried on prospecting in a small way for a number of years. Commercial production of quicksilver began in July, 1873, with the mine's discoverer as superintendent, who first built here the Neate coarse-ore furnace. This first producing period continued to 1880, yielding a total of 11,530 flasks in the seven years. The St. John's Consolidated Quicksilver IMining Company reopened the mine in 1899 and continued production up to 1909, following which only a small amount of development work and occasional retimbering to keep the mine open was done until the present operators took over the property in 1914. The total recorded production of the St. John's mine has been 16.453 flasks of quicksilver to the end of 1917. GEOLOGY. A detailed study of the geology of the St. John's orebodies and adjacent formations was made in 1916 by Oscar H. Hershey, from whose report^ most of the following geological data are abstracted, and the accompanying maps. (Plates XX and XXI) reproduced. The rocks consist primarily of a series of sedimentary beds and igneous intrusions therein. The intrusive rocks have been highly altered, at least near the surface, and only remotely indicate their original condi- tion. The sediments are Lower Cretaceous in age and appear to Ix' divisible into two series, the earlier of which may possibly be Fran- ciscan, but because of not yet being definitely identified as such is here designated the 'Lower Series'. The upper series is bf Knoxville for- mations. The Lower Series: The summit of Mt. St. John and the rugged ridge extending thence northwest to the old St. John's furnace has extensive outcrops of rather hard rocks consisting basally of a light-gray, rather Iieavy-bedded sandstone, succeeded by shaly and calcareous layers of dark-graj^ color. These rocks strike northwest and near the summit of the mountain dip southwest 50°, but they straighten to nearly vertical toward the northwest. The sandstone may be 80 feet thick and the shaly division several hundred feet. Beyond a fault of small throw as shown on the map, the sandstone appears to have been cut out and only the shaly belt outcrops. The shaly division seems to become more calcareous toward the northwest and at a i)oint about 500 feet north- west of the old furnace, it appears as a considerable body of light-gray impure limestone. This limestone is traversed l)y a network of quartz 'An unpublished private report made for the St. John's company, and kindly loaned with accompanying maps to the present author by courtesy of the manager, Mr. Clifford G. Dennis, with permission to publish. I QUICKSILVER RESOURCES. 173 Francisco. It is in Sec. 33, T. 4 N., R. 3 W., M. D. M., 6 miles north- east from A'allejo, with an excellent oiled road to within 1 mile of the furnaces. The mine is at the northern end of the Sulphur Springs INIountain ridge. Cinnabar was first found liere in 1852 by John Neate, who carried on prospecting in a small way for a number of years. Commercial production of quicksilver began in July, 1873, with the mine's discoverer as superintendent, w^ho first built here the Neate coarse-ore furnace. This first producing period continued to 1880, yielding a total of 11,530 flasks in the seven years. The St. John's Consolidated Quicksilver IMining Company reopened the mine in 1899 and continued production up to 1909, following which only a small amount of development work and occasional retimbering to keep the mine open was done until the present operators took over the property in 1914. The total recorded production of the St. John's mine has been 16,453 flasks of quicksilver to the end of 1917. GEOLOGY. A detailed study of the geology of the Sti John's orebodies and adjacent formations was made in 1916 by Oscar H. Hershey, from whose report^ most of the following geological data are abstracted, and the accompanying maps. (Plates XX and XXI) reproduced. The rocks consist primarily of a series of sedimentary beds and igneous intrusions therein. The intrusive rocks have been highly altered, at least near the surface, and only remotely indicate their original condi- tion. The sediments are Lower Cretaceous in age and appear to 1k' divisible into two series, the earlier of which may possibly be Fran- ciscan, but because of not yet being definitely identified as such is here de.signated the 'Lower Series'. The upper series is of Knoxville for- mations. The Lower Series: The summit of Mt. St. John and the rugged ridge extending thence northwest to the old St. John's furnace has extensive outcrops of rather hard rocks consisting basally of a light-gray, rather heavy-bedded sandstone, succeeded by shaly and calcareous layers of dark- gray color. These rocks strike northwest and near the summit of the mountain dip southwest 50°, but they straighten to nearly vertical toward the northwest. The sandstone may be 80 feet thick and the shaly division several hundred feet. Beyond a fault of small throw as shown on the map, the sandstone appears to have been cut out and only the shaly belt outcrops. The shaly division seems to become more calcareous toward the northwest and at a point about 500 feet north- west of the old furnace, it appears as a considerable body of light-gray impure limestone. This limestone is traversed by a network of quartz 'An unpublished private report made for the St. John'.s company, and kindly loaned with accompanying map.s to the present author by courtesy of the manager, Mr. Clifford G. Dennis, with permission to publish. 174 CALIFORNIA STATE MINING BUREAU. seams. Throug-hout a larger part of tlie formatiou the quartz was very abundant, and has given rise, through the decay of the limestone, to rough outcrops of very porous flinty quartz. This quartz-skeleton country has been locally called 'carbonate rock', and most of it on this property is associated with serpentine. In the particular area now under discussion, the main body of which is about 1000' long and 300'- 400' wide, some serpentine was recognized and a fine-grained granular rock that represents a basic intrusion different from that which altered to serpentine ; but, the main body is a great mass of skeletal quartz with interstices either filled with fine-grained, calcite-like limestone, or is leached and iron-stained. The structure and hence thickness are not clear. Probably most of it has a rather low, southerly dip, and the maximum thickness may be not over 100' or 150'. The attitude of the 'Lower Series' in relation to that of the rocks surrounding the area indicates that it is bordered on the northeast by a fault of considerable throw and on the southeast b}' a fault of great throw. The northwest limit is probably a fault, but the southwest limit has sufficient irregularity as to suggest that it is the line of orig- inal contact between the Lower Series and the overlying Knoxville series, a contact that probably represents a non-conformity. Knoxville Series : This series consists predominantly of a great thick- ness, probably many hundreds of feet, of dark-olive, to nearly black soft shale, which is evenly and thinly laminated. The lower portion of it is characterized by the presence of many lentils, usually not over 2' or 3' in length and 2" to 6" thick of fine-grained compact limestone of brownish-gray color. These weather out into hard boulders that accumulate along the gulleys. The limestone lentils may be seen at various places on the 100', 160', and 260' levels. They are of no economic significance but aid in the determination of the structure. At a higher horizon, thin beds of brown, fine-grained, soft, impure sandstone appear in the shales. Particular attention was given to a study of the attitude of the Knoxville rocks, because of an opinion then held at the mine that the ore occurs chiefly where faults are intersect- ing certain sandstone ])eds. The mine workings, so far as studied, are in a fairly uniform block of Knoxville formation dipping northeast at an average angle of 35°, though locally somewhat di.sluihed especially along the faults. Serpentine : The sedimentary series were inti-uded b}' peridotite, which was subsecjuently altered to serpentine. The serpentine areas were doubtless at one time co-extensive with wluit hns been mapped as serpentine and 'silica-carbonate' rock, except a portion northwest of the old St. John's furnace discussed above. QUICKSILVER RESOURCES. 175 'Silica-Carbonate Rock': A large part of the serpentine has been altered to an aggregate of carbonates of iron, magnesia, and lime traversed by small veins of chalcedony, opal, and quartz. This weathers into a skeleton of rusty quartz. Except on Mt. Lutfman, none of the quicksilver deposits of the property occur in this material, but there is an area extending southwest from the new furnace, in which conditions appear to be favorable for the formation of ore in this phase of rock. Dike Rock: The important rock from an economic standpoint, is a certain type of intrusive that occurs in many relatively small bodies in the easternmost one-third of the property. The rock has been highly altered and at present appears to be largely a fine-grained aggregate of silica and carbonates. In outcrop it is a pinkish-brown, fine-grained rock consisting of white, fine-grained replacement quartz abounding in small porous areas stained brown by limonite. There are some black manganese stains and traces of a carbonate, probably calcite. Under- ground it is whiter and more compact, and has frequently very fine- grained pyrite disseminated. This is the rock that in former published accounts was designated as a metamorphic sandstone. On the 350-foot level it has been found apparently much less altered than above, and by examination of thin-sections has been identified as a 'meta-andesite'. It is a light-gray crystalline rock, having somewhat the appearance of a very compact, fine-grained sandstone, resembling some of the Fran- ciscan metamorphic sandstones. "The important fact is that it is an intrusive rock that was injected into Knoxville shales in bodies that are generally more or less elongated in a north to northwest direction, forming short blunt dikes, though a few are rounded or irregular chimneys to which the term dike can only be applied by courtesy. Some of them tend to follow the bedding on the dip, but most of them cut the bedding planes at high angles. Where the borders are not faults, the contacts are typically intricate intrusive contacts, with angular fragments of the shale in the dikes. Furthermore, the shales near the contact have been altered to a hard, black, siliceous shaly material. No further evidence is needed to prove that these bodies are intrusive. These dike-like masses show no tendency to pinch with depth, but rather the opposite." To facilitate correlation of these dikes from level to level, they have been designated by letters, on the map. At least 11 of these dikes have been identified, the most impor- tant ones from the standpoint of associated orebodies thus far devel- oped, being dikes C, D, and E. Faults: The rocks of the area are traversed in various directions by many faults, most of them of small displacement. To facilitate their correlation from level to level, the more important ones are designated on the map by numbers. At least 20 of these have been so designated. 176 CALlFOKNrA STATK WINING BUREAU. 1 o 4 -^-^y^^^-^ ! /yl^ CO - -^ A C, -•''/ z UJ Z C5< •» 0^' J ^=^ %' 2 2 z --$ i / * ^ ^ ^ ^x a: O UJ UJ > _i o o u o UJ -J r^ •> \V-*° >^ /^ > ^ > HI _i < z 2ij ^ Q /' CQ _l 1/1 d O ^ o 1- u h U. * O '// A. \ ^ . O O O z < _l o UJ H O _) /p. FAULT O 10 CO Z if) O in J' ^^ ^ ^ cc I - z^::^ LlI o \\ ^^ <. Q -> \\ // % Z D 0) m T- za ^ OO SIf See p. 217, post. 188 CALIFORNIA STATE MINING BUREAU. This includes the yield of the Mt. Jackson mine adjoining, as the two were operated in conjunction for a number of years, and their individ- ual figures are not separable. As noted in a foregoing paragraph, from 1882 to 1894, tlie Great Eastern mine was the only quicksilver producer in Sonoma County. This Great Eastern-Mt. Jackson lode is peculiar because of its isola- tion from other workable quicksilver deposits and from any known eruptives. It resembles somewhat the Culver-Baer ledge with its bold, ochreous outcrop between a serpentine hanging-wall and sandstone footwall. (Seen at left of Photo No. 38.) The strike is north of west and dips north at 50'' to 60^, being steeper at the surface. The Great Photo No. 38. Great Eastern Mine, near Guerneville, Sonoma County. Ledge outcrop at left; furnaces in center; furnace dump at right. Eastern vertical shaft sunk in the sandstone footwall is down 550', with two winzes of 160' each sunk from the 500' level. There is also a 400' drift on the 500' level. The collar of the shaft is about 200' below the upper outcrop, and at that level there is a tunnel in 1100', with connecting drifts and stopes in the ledge above. From the shaft there are levels at 150', 220'. 360' and 500', respectively. The ore shoot is enclosed within the ledge of opalized rock which was originally probably mostly serpentine. Becker^ considers that this silicification ''preceded the deposition of ore, though somewhat closely connected with it." Occasionally a little pyrite accompanies the cin- nabar. The ledge filling is characterized by numerous cross-fi.ssures, at a flat angle, filled with quartz stringers, like the 'ladder veins' described by Lindgren.- The ore forms principally in relatively softer zones in this material. Accompanying the ore, frequently in stringers 'Becker, G. F., r.colon.v nf the quicksilver deposits of the Pacific Slope: U. S. Geol. Surv.. Mon. XIII. p. :;G4, ISSS. 'Lindgren, Waldemar, Mineral Deposits: pp. 133, 146, 1913. QUICKSILVER RESOURCES. 189 parallel to the above-mentioned quartz partings, is a brittle black bitumen, which may possibly be grahamite, as its properties correspond in part at least to that bitumen. It is partly soluble (even in frag- ments not powdered) in ether; completely soluble in chloroform; dis- tinctly soluble in California kerosene; apparently insoluble in Penn- sylvania petrolic ether of 88° Baume; and is broken up by, but only slightly soluble in carbon tetrachloride. It deflagrates, and only partly melts in a candle flame. This bitumen is usually associated with good ore values. For several years previous to 1905 (in which year it expired), the Great Eastern Company had a lease on the Mt. Jackson ground adjoin- ing and worked it through the Great Eastern levels. The earthquake of April 18, 1906, shook from the outcrop cliff near-by a large rock which rolled into the shaft, killing three men coming up in the cage. It also partially wrecked the shaft. The damage to the shaft has been repaired, but the lower levels have not been operated since, being at present filled with water. Ore reduction was resumed in May, 1915. Only the upper portions of the mine, above the hoist level, are being worked. The ore is broken in stopes and open-cuts and dropped through chutes to the main adit level. There is an abundant water supply from several springs on the property. The hoist was operated by a w^ood-burning steam plant. The crusher plant adjoins the hoist and a gravity tram conveys the ore to the furnaces. After screening through the grizzly, the wet fine ore is hauled in wheelbarrows and spread out on a level 'patio' in the sun to dry. After drying, it is returned to the ore-bins by the same route. There is too much handling of the ore by manual labor before it gets to the furnace. When visited by the writer in September, 1917, the old Knox & Osborne 11-ton coarse-ore furnace was being partly torn down to be rebuilt as a Scott fine-ore furnace of about 80 tons capacity. Their #1 Scott fine-ore furnace has a capacity of 18 tons. There are two 'D' retorts, 18" and 24" respectively; but they are not much used now, as there is very little soot to handle since the use of oil fuel instead of wood, and the construction of the new concrete condensers. The 18- ton furnace was using 100 gal. of 23° B. fuel oil per 24 hours at a cost of slightly over 3^ per gallon. A Hauck crude-oil burner is used, with compressed air for atomizing. On the retort, a 'Rotary Oil Burner' is used, driven by a small water-wheel. With this, it requires 30 hours to heat up the retort, after which the consumption of oil is 100 gal. per 48 hours. Condensers on No. 1 Scott furnace : No. 1 is a 2-chamber, brick con- denser. 10' X 12' X 22'; No. 2 is a 2-ehamber, concrete unit, 16' X 10' X 22' ; No. 3 is a 4-cliamber, concrete unit, 16' x 8' x 22'. These concrete condensers cost about $600 apiece. They are built with 190 CALIFORNIA STATE MINING BUREAU a 6" wall, i-einforeed with wire and painted on the inside with 'neat cement' to fill the pores. In the cleaning-iip, these walls are simply hosed down with a stream of water. The old brick condensers which these replaced, yielded 8 flasks of quicksilver. They were set in cement mortar. In September, 1917, the ordinary qnicksilver flasks were costing $2 apiece. Roeth had had some cast of stove-iron, to. his own pattern, at a foundry in Oakland at a cost of approximately 75^ apiece, weight 18 pounds. At that time, some of these had made three trips to San Francisco without damage. Bibl. : Cal. State Min. Bur., Reports IV, p. 336 (table) ; V, p 95 ; VIII, p. 633 ; XI, p. 460 ; XII, 371 ; XIII, p. 602 ; XIV, p 347 ; Chapter rep. bien. period. 1913-1914, p. 175 ; Bull. 27, pp 108-112, 226, 239, 246. U. S. G. S., Mon. XIII, pp. 362-364 An. Rep. XX, Pt. VI, p. 271 ; Min. Res. 1883, pp. 394, 396, 397 1902, pp. 251, 253 ; 1907, Pt. I, p. 680 ; 1908, Pt. I, p. 690 ; 1915 Pt. I, p. 271. MiN. Res. W. of Rocky Mts., 1875, p. 14; 1876, p. 20. Min. & Sci. Press, vol. 89, p. 391. Great Northern Group. In Sec. 2, T. 10 N., R. 8 W., M. D. M., near Pine Flat. Abandoned. Bibl.: Cal. State Min. Bur., Report XIV, p. 348; Chapter rep. bien. period. 1913-1914, p. 176; Bull. 27, p. 112. Hurley Prospect. In Sees 4 and 5, T. 10 N., R. 8 W., M, D. M., near the Sonoma mine. Abandoned. Bibl.: Cal. State Min. Bur., Report XIV, p. 348; Chapter rep. bien. period. 1913-1914, p. 176 ; Bull. 27, p. 112. Lookout Group. In Sec. 32, T. 11 N., R. 8 AV., M. D. M., near ihe Eureka group. Abandoned. Bibl.: Cal. State Min. Bur., Report XIV, p. 348; Chapter rep. bien. period, 1913-1914, p. 176; Bull. 27, p. 113. Lucky Stone Group. In Sec 4, T. 10 N., R. 8 W., M. D. M., near Pine Flat. Abandoned. Bibl.: Cal. State Min. Bur., Report XIV, p. 348; Chapter rep. bien. period, 1913-1914, p. 176; Bull. 27, p. 113. Maricoma Prospect (Santa Rita). In Sec. 36, T. 10 N., R. 8 W., M. D. ]VI., near Pino Fiat. Abandoned. Mt. Jackson Mine. Mi. Jackson Quicksilver Mining Company, owner; 0. T. Ilassett, president, Geyserville, R. F. D. This mine adjoins the Great Eastern mine near Guerneville on the northwest, but QUICKSILVER RESOURCES. 191 has no plant of its own, having been Avorked through the Great Eastern levels for a number of years by the Great Eastern company under lease. The I\It. Jackson mine has been idle since 1905, but recent press reports (March, 1918) state that an option has been given to J. H. Kendall. 64 Regent St., Oakland, who is reopening one of the upper tunnels. Bibl.: Cal. State Mix. Bqr., Reports VIII, p. 633; XII, p. 371; XIII, p. 602; XIY, p. 349; Chapter rep. bien. period, 1913- 1914, p. 177; Bull. 27, pp. 108-112. Napa Prospect. In Sec. 11, T. 10 N., R. 8 W., M. D. M., near Pine Flat. Abandoned. Bibl. : Cal. State ]\Iix. Bur., Report XIV, p. 349 ; Chapter rep. bien. period, 1913-1914, p. 177 ; Bull. 27, p. 113. ¥ New Sonoma Mine (formerly Sonoma Consolidated Group, includ- ing Crown Point and Hope). T. Gale Perkins et al., owners. Pine Flat postoffice, or #1822 Pacific St., San Francisco. This group of 7 claims is in Sees. 4 and 5, T. 10 N., R. 8 W., M. D. M., in the Pine Flat district, about 16 miles northeast of Healdsburg. About 1910, this property was bought by the Culver-Baer company, particularly for its surface equipment including a Scott furnace, which was transferred to the Culver-Baer mine 5 miles to the northwest. Under the impres- sion that the claims were patented the Culver-Baer company did no work on the mine for several years, following which the ground was ' relocated by the present owners, as they found it to be unpatented. The last previous operations were by the Crown Point company. Pro- duction began with an output of 50 flasks of quicksilver in 1873. The early production was from rich surface pockets. There is an adjacent serpentine belt, striking N. 48° W. Perkins states that he has found the orebody at 5 separate levels and points in a zone striking southeast, but swinging around to the south and dipping easterly. He has driven 9 crosscut adits up to 110' in length, until each one cut the orebody, to prove its continuity. He now proposes to drive a lower adit of 1100' in length. There is con- siderable native quicksilver with the cinnabar, particularly in the ore near the surface. It is proposed to concentrate the soft, surface ma- terial. Some ore taken out in the course of development was retorted in 1917. The reduction equipment is a 'D' retort of 1000 lb. capacity, being 12" high x 32'' Avide x 9' 2" long. A water spray is used in the conden.ser-pipe, similar to that at the Oat Hill mine described else- 192 CALIFORNIA STATE MINING BUREAU. where herein -^ but Perkins states that he obviates loss of floured quick- silver floating away, by syphoning the flow to successive settlers. Bibl. : Cal. State Min. Bur., Reports XIII, p. 503; XIV, p. 350; Chapter rep. bien. period, 1913-1914, p. 178; Bull. 27, pp. 102. 112. U. S. G. S., Mon. XIII, p. 377; Min. Res. 1902, p. 253. Min. Res. W. of Rocky Mts., 1874, p. 30 ; 1875, p. 14. Trans. A. I. M. E., vol. Ill, p. 290. Occidental and Healdsburg Group. In Sec. 10, T. 10 N., R. 8 W., M. D. M., near Pine Flat. Abandoned. Bibl. : Cal. State ]Min. Bur., Report XIV, p. 349 ; Chapter rep. bien. period, 1913-1914, p. 177 ; Bull. 27, p. 114. Old Chapman Prospect. In Sees. 25 and 30, T. 10 N., R. 8 W., M. D. M., at the mouth of Sausal Creek caiion, on Deer Creek. On the south side of Deer Creek a line of croppings, course about N. 15° W., runs down the slope toward the creek, but the underground workings have not disclosed any continuation of ore in depth. Abandoned. Bibl. : Cal. State Min. Bur., Report XIV, p. 349 ; Chapter rep. bien. period, 1913-1914; Bull. 27, p. 114. Pacific Group (Crystal or Red Cloud; also known locally as the Abbey). Wm. Jacobs, owner. Pine Flat. This group consists of pat- ented claims in Sees. 5 and 6, T. 10 N., R. 8 W., M. D. M., near the New Sonoma group in the Pine Flat section. Only a small amount of prospecting work has been done for several years past. There is no reduction equipment. Bibl: Cal. State Min. Bur., Reports XIII, p. 603; XIV, p. 349; Chapter rep. bien. period. 1913-1914, p. 177; Bull. 27. p. 114. U. S. G. S., Min. Res., 1902, p. 253. Rattlesnake Mine. G. W. AVheeler and Frank G. Kiessig, owners, Pine Flat ; R. A. Sallee, l&ssee. Pine Flat. This group of 3 claims and 2 mill-sites is in See. 31, T. 11 N., R. 8 W., U. D. M., on the road between the Culver-Baer mine and Pine Flat. This mine is credited with a production of 65 flasks in 1875, entirely from native quicksilver, with which was associated an oily bitumen. Not only was the metal entirely in the native state, but it is claimed that there was considerable mercurial vapor in llic underground workings. The mine was idle and inaccessible for many years, until reopened liy the present owners in 1916. A few flasks of quicksilver have since been recovered by wasli- ing and retoi-ting. When visited by the writer in September, 1917. 'See p. 211 ' QUICKSILVER RESOURCES. 193 the lessee was trying a revolving' screen and sluice boxes for washing the material. Judging from the surface, the country i-ock consists of altered sedi- mentaries, with occasional small occurrences of serpentine. The native metal occurs in a black, brecciated mass and gouge. No definite walls have been found. There are two adits, each in about 200', the upper one being at the road level, and the other 60' below, near the portal of which tlie retort is located. The furnace consists of 3 pipes of 300 lb. capacity, each. Like the Socrates mine, the difficulty here is to handle the native metal economically. If the underground situation can be handled successfully and safel}^, it would seem that the ore-dressing end might be solved by concentrating tables or b}' hj^draulic settlers. The ore is rather wet and requires drying if it is to be furnaced. If collected direct by concentration, however, the native metal would not need to be put through a furnace. Only such cinnabar as would appear in the concentrates would need to be roasted. Bilil. : Cal. State Min. Bur., Eeports IV. p. 336 (table) ; XIII, p. 603; XIV, p. .349; Chapter rep. bien. period, 1913-1914, p. 177; Bull. 27, p. 115. U. S. G. S., Mon. XIII, p. 377. Min. tKES. W. OF Rocky Mts., 1874, p. 37 ; 1875, pp. 14, 176. Trans. A. I. M. E., vol. Ill, p. 273. Socrates Mine (originally Pioneer; includes Pontiac Group; also Mercury Group). Socrates Consolidated Mining Company, owner; . iWm. H. Jordan, attorney, ]\Ionadnock Building, San Francisco ; U. S. ■ Mines Development Corporation, lessee ; Paul Messchaert, pi-esident ; B. G. Holt, secretary; office, 514 Sheldon Bldg., San Francisco. This group is at the junction of Sees. 32 and 33, T. 11 N., R. 8 W., and Sees. 4 and 5. T. 10 N., R. 8 W., M. D. M., in the Pine Flat district, on the divide between Big Sulphur and Little Sulphur creeks, 6 miles south- east from The Geysers. Elevation 3,000' at mine ; 2500' at furnace. The Pioneer claim of this group was the first quicksilver claim located in Sonoma County. The Socrates, proper, is patented, besides which there are 53 other claims mostly unpatented. In 1904, the adjacent property of the Mercury Mining Company was taken over by the Socrates Company. It is about equidistant, 20 miles, from Healdsburg and from ^Middletown, being on the road between the two which passes through Pine Flat. Owing to the difficulty of handling the native metal which makes up the major portion of the values here, the mine was idle for many years. The occurrence of tiemannite, the selenide of mercury, has also been noted in the Socrates mine. The recorded production for the years 1900-1917, inclusive, totals approximately 3,500 flasks of quicksilver; there being no segregated figures of the early-day output, which is reported to have been about 1000 flasks. lS-35540 394 CALIFORNIA STATE MINING BUREAU. In 1903, a White-Howell rotary roaster was installed and operated for several months on the Socrates ore. The surface plant was destroyed by a forest fire in the fall of 1907. During 1908-1910, the Socrates Development Company, operating the property under bond, made a fair output of quicksilver, employing a Huntington mill and a Woodbury concentrator. The concentrates were retorted. The pres- ent operators reopened the mine in 1916, and have built a 40-ton Scott furnace. (See Photo No. 39.) They have cut down the length of the Photo No. 39. Socrates Mine surface plant, Sonoma County. The mine is on the ridge at the left. White-Howell kiln and reinstalled it as an ore-drier above the Scott furnace.^ The country rocks are sandstone and serpentine. The ore occurs in a ledge of soft opaline rocks, considerably fractured, but in the upper levels it is also in sandstone. The strike is about N. 20° W. In the upper levels, the footwall consists of sandstone and shales slightly swelling, and there is a heavy hanging wall of black gouge. A 'horse' of black serpentine runs through the middle of the ledge matter. In the lowest level, the dip appears to have reversed, so that the black gouge is on the footwall, and the hanging-wall is a hard serpentine. There the dip is nearly vertical. In llu' upper levels, the quicksilver ■See Photo No. 51. post. QUICKSILVER RESOURCES. 195 was nearly all iu the native form ; but in the lowest level when visited by the writer, a considerable proportion of cinnabar was showing in the ore. The values occur both disseminated and in veinlets. Some pyrite or marcasite and calcite are associated. Chlorite, an end pro- duct of the alteration of serpentine, is also abundantly present. The ore shoots are from 18" to 5' in width, in an ore zone of 60' maximum width and 30' average. There are 3 main adits (#1, #2, and #3) and 2 others, (P| and #4) and the vein has been opened up for a length of 750'. A depth of 400' below the top of the hill has been reached. Many of the old workings are inaccessible. Square-set timbering is used. There is a fair local supply of oak, pine and 'fir.' A single-rope aerial tram, 1875' long, steam-driven, transports the ore to the furnace bins. Equipment also 1 includes a compressor, Water-Leyner jack-hammer drills, and an air- ( driven hoist. Keduction equipment includes the rotary ore-drier and the 40-ton •Scott above mentioned, also 2-18" 'D' retorts. When visited by the writer in September, 1917, the surface plant was being rearranged and development work carried forward underground. A small amount of I- sorted ore wa^ being put through one retort. They had added 16' onto the top of the dust-chamber of the Scott furnace, and were covering it with a sheet-iron top to be used as a final drier before the ore is charged to the furnace. From the tramway bin, the ore was to pass through the rotary drier to another bin, thence by a belt conveyor to the slueet-iron drier. In February, 1918, a total of 70 men were employed, 32 of whom were in the mine. At the present writing (April, 1918), we are informed that operations are shut down. Bibl. : Cal. State Mm. Bur., Report XIV, p. 350 ; Chapter rep. bien. period, 1913-1914, p. 178; Bull. 27, pp. 115-116. U. S. G. S., Mon. XIII, p. 376 ; Min. Res. 1902, p. 253 ; 1906, pp. 493, 497; 1907, Pt. I. p. 680; 1908; Pt. I, p. 690; 1909, Pt. I, p. 554; 1910, Pt. I, p. 701 ; 1915, Pt. I, p. 271. Geol. Surv. op Cal., Geol, Vol. I, pp. 88-91. Min. Res. W. op Rocky Mts., 1875, pp. 14, 176, 177. Min. & Sci. Press, Vol. XC, p. 22, Jan 14 1905. Squaw and Big Chief Claims. L. D. Kissack and John June, Clover- dale, owners. These claims are in Sec. 4, T. 11 N., R. 9 W., M. D. M., adjoining the Cloverdale mine, 12 miles east from Cloverdale ; eleva- tion 2200 feet (bar.). The ore is similar to that of the Cloverdale. A tunnel and a short incline from it have been driven in about 60 feet, 196 CALIFORNIA STATE MINING BUREAU. and a small amount of hii^li ii'rade ore sorted from the material taken out. Assessment work, onlv, is maintained. Bibl. : Cal. State ^NFin. Bur., Repoi-t XIV, p. 3')!; Chapter rep. Men. period, 1913-1914, p. 179. Walker Prospect. On patented ground in Sec. 7, T. 8 N., R. 10 W., j M. D. M., near Guerneville, owned by the Meeker Estate of Camp Meeker. A few stringers carrying cinnabar are said to have been : found, but nothing of consequence developed. ' Bibl. : Cal. State Min. Bur., Report XIV, p. 351 ; Chapter rep. bien. period, 1913-1914, p. 179; Bull. 27, p. 116. Wall Spring Prospect. H. C. Wall, Hilton, owner. In See. 30, T. 8 N., R. 9 W., M. D. M., near Hilton. Idle. Bibl. : Cal. State Min. Bur., Report XIV, p. 351 : Chapter rep. bien. period, 1913-1914, p. 179; Bull. 27, p. 117. QUICKSILVER RESOURCES. 197 STANISLAUS COUNTY. There is aii extensive area of Franciscan rocks following along the trend of the Diablo Range, from the canon of Corral Hollow Creek at Tesla, sontheasterly for at least 75 miles. The Stayton quicksilver dis- trict at the junction of ]\Ierced, San Benito and Santa Clara counties is at the southern end of this belt. Within this belt in western Stanis- laus County, and on the eastern slope of the range, are several quick- silver prospects, from some of which metal has been produced. These are east of and near the Red Mountain magnesite district. There are four groups on the upper branches of Orestimba Creek, and one group on Deer Park Creek or the north branch of Arroyo del Puerto. The total output of the district appears to have been slightly in excess of 200 flasks of quicksilver. Adobe Valley Mine (formerly Stanislaus). E. P. Newhall, owner, Box 354, Livermore. This consists of 320 acres of patented laud in Sees. 23 and 2-4, T. 6 S., R. 5 E., M. D. M., east of the Phoenix mine, 21 miles from Patterson. The Patterson & Western Railroad, recently built up the Arroyo del Puerto, passes about two miles from this prop- erty. This prospect was opened up in 1884, and a small amount of quicksilver produced up to 1888, since which time, it appears to have been idle. The country rock is a gray sandstone. The ore occurs in 3 veins which have a northerly strike, and are cut by a 2-compartment vertical shaft sunk to a depth of 180'. The upper vein, with dip of 45° was opened up by a series of open-cuts, short tunnels, and an incline shaft 70' deep. The vertical shaft cut the first vein at a depth of 40', at which level a drift was run 30' N., then a crosscut to the hanging-wall, showing the orebody 4'-5' wide. At the 75' level, the second ( ?) vein was cut, and a drift run 100' N. This may be a spur from the lower vein, as it dips at a very flat angle ; and is irregular in shape and siz^. At 100' depth, the third orebod.y was cut, showdng cinnabar in a fine- grained dark sandstone, with associated pyrite. The shaft is closed below 120' in depth. It is stated that at 170' a crosscut was driven westerly, which cut the vein at 70' showing a width of 15'. This lower orebody shows cinnabar disseminated in the sandstone, as well as occurring along the fracture zones. There is considerable black clay gouge on the hanging-w^all. There is no reduction equipment at present on the property. kBibl.: Cal. State Min. Bur., Reports X, p. 680; XIV, p. 632; Chapter rep. bien. period, 1913-1914, p. 206; Bull. 27, p. ]89. Crocker-Winship Prospect. M. I. Crocker and K. D. Winship, owners, San Francisco. There are some quicksilver prospects on Sec. 31, T. 5 S., R. 5 E.. M. D. M., on which it is stated some work was done about 1913, under a lease, by the Mt. Boardman Quicksilver Company. 198 CALIFORNIA STATE MINING BUREAU. Gigax Claims. A. B. Gigax, of Patterson, is reported to have recently located claims on a quicksilver prospect on Mt. Boardman in the northwestern corner of the county, near the Newhall claims. Interaational Mine, In Sec. 3, T. 8 S., R. 6 E., M. D. M., on the south fork of Orestimba Creek, southeast of the Phoenix mine. The prospect was worked for a short time, prior to 1880, and some metal produced with a small furnace and retorts; but it has been idle since. Bibl. : Cal. State Min. Bur., Report X, p. 680. Newhall Mine (formerly Deer Park). E. P. NewhaU Quicksilver Mining Company, owner; E. P. Newhall, president, Box 354, Liver- more; Chester M. Beck, secretary. Mills Building, San Francisco. This group of 7 claims is on Deer Park Creek in See. 32, T. 5 S., R. 5 E., M. D. M., 22 miles from Patterson via the Arroyo del Puerto. There are several croppings which show cinnabar in sand- stone and in serpentine. Some development work has been done, prin- cipally by a tunnel ; but no metal has as yet been produced, and there is no reduction equipment. Some work was done on these prospects in 1913 under a lease by a company known as the Mt. Boardman Quick- silver Company, who are stated to have also had a lease on adjoining land in Sec. 31 owned by K. D. Winship and M. I. Crocker of San Francisco. Bibl: Cal. State Min. Bur., Reports X, p. 681; XIV, p. 632; Chapter rep. bien. period, 1913-1914, p. 206. Phoenix Mines (includes the former Summit, Grayson, and Ores- timba mines; also referred to as the Hayward). Alvinza Hayward Estate and Mrs. Emma Rose, New York, owners; E. S. IMcCurdy, man- ager, 576 Mills Building, San Francisco. The Summit-Grayson group is in Sees. 20, 21, 28, and 29, and the Orestimba group in Sees. 25, 35, and 36, all in T. 6 S., R. 5 E., M. D. M., 39 miles southeast of Liver- more by a good road. It is also 24 miles south of west from Patterson, but the road is poor. Elevation 2150' (bar.). Oak timber is avail- able, and the water supply is from springs. There are 7 patented claims, 4 millsites, 6 unpatented claims and 160 acres of timber land in the Summit-Grayson group ; and 2300 acres of patented land in the Orestimba group. This property was first worked in the 70 's by a Mr. Waterford, and sold to Hayward about 1901. The furnace was built in 1902-1903. Tlie mine was reopened in Septem- ber, 1915, and operated during the higli prices prevailing for quick- silver during that winter, closing down in June, 1916, becau.se of the decline in market price of quicksilver, the low grade of the ore, and the need of a larger equipment and more extensive development to handle such low-grade ore. The total production to date lias been nearly 200 fla.sks. QUICKSILVER RESOURCES. 199 The country rocks are sandstone and serpentine. The cinnabar is disseminated with infiltrated silica in an altered weathered sandstone; also in serpentine. The Summit-Grayson group is opened up mainly by 3 crosscut tunnels, connected by raises and winzes, which show 3 zones of mineralization ; Summit vein, strike N. 15° E., dip 60° SE. ; a belt of sandstone, with northwesterly strike, crossing the Summit vein ; the Grayson vein, with a northwesterly strike and northeasterly dip. m04 - - ■ ■ - •'^'^iBMfc^J'ij'Jl^^^^B /^^^^^^^^^^^^^^■^^^^l Ivd:„...... II!!!r Photo No. 40. Fifty-ton Scott furnace and condensers at Phoenix Mines, Stanislaus County. Photo by F. L. Lowell. The gangue contains calcite. The principal development is on the Summit vein, which has an average width of 10'. The grade of the ore averages 0.25%-0.30% mercury. The lowest adit is the main haulage level. No. 2 level is 100' below No. 1, and #3 is 110' below No. 2. Ore was extracted by overhand stopes. Only a small amount of work has been done on the Orestimba group, where the country rock appears to be a silicified shale. When last operated equipment included a 12"x7^"xl2" Chicago Pneumatic compresor and machine drills, and haulage was by mule- train ; but the movable equipment has now been taken away. There is a 50-ton Scott furnace (see Photo No. 40). Bibl. : Cal. State Min. Bur., Reports X, pp. 680, 681 ; XIII, p. 603; XIV, pp. 632, 633; Chapter rep. bien. period, 1913-1914, pp. 206, 207; Bull. 27, pp. 188, 180. U. S. G. S., Min. Res., 1915, Pt. I, p. 271. 200 CALIFORNIA STATE MINING BUREAU. TRINITY COUNTY. Surface indications of quicksilver ores are found in several places throughout Trinity County, but active mining for this metal ha.s only been carried on in tlic northeastern part of the county, between Crow Creek, a tributary to the ea.st fork of the Trinity River, and the north fork of tlie east fork of Trinity River. On the surface the country rock is principally serpentine, usually very hard. Chromite and chrysotile asbestos are found in these serpentine areas. There are exposures of metamorphic rocks, principally sandstones, west of the quicksilver zone, on the stope toward the North Fork. The material in which the quicksilver orebodies form is a very much altered rock, probably originally igneous, as it appears to have been porphyritie. The principal commercial output of quicksilver has come from the Altoona mine, with some also fi'om the Integral mine. The recorded production for the county is shown by the following tabulation : Quicksilver Production of Trinity County. Year Flasks Value Year Flasks Value Altoona before 187.5 (estimated)* 1875t 1876* 1877 1878 1879 1880 1881 18901 1891 1895 1896 1897 1898 1899 1900 1901 I l.,000 l,.5O0 1.979 1,H17 1,534 1.919 245 ■•?. Christ}'^ on furnaces and condensers, respectively, at New Ahnaden, California. Is it not oiit-of-place at this point to remark that m;iny experiments of various operators have been conducted. al)solutely unaccompanied by any thought or attempt at technical control. This often results in the hasty adoption of some method or piece of apparatus, M'hicli a care- ful control would have shown to be useless or inefficient ; or it may result in the hasty rejecting of what might ultimately prove to be a really economic feature. PROPERTIES OF MERCURY OR QUICKSILVER. To assist to a better understanding of the subsecpient discussion, the properties and some of the reactions characteristic of this element, are here summarized: Mercury is tlie only metal which is fluid at ordinary temperatures. According to various authorities it solidifies at — 39.4° C." "It contracts upon solidification, and forms a wliite, very ductile and malleable mass, which is readily cut with a Knife." Sp. gr., lluid, at 0° C. is 13.59; solid, 14.19. "Its electrical conductivity according to Mattliiesen at 22.8° C. is 1.63, silver at 0° being taken as 100. * * * Mercury is volatile to a sliglit extent at ordinary temperatures, and according to Merget even below — 44° C. This may be proved by suspending gold leaf above a vessel containing mercury, when it will become coated at ordinary temperatures with a white layer of amalgam. Tlie boiling point of mercurv, according to Dulong and Petit is 360° C: according to Regnault, 357.25° C. It is converted into a colorless vapour, the density of which is given as between 6.7 and 7.03. The rapidity with which mercury vola- tilizes on boiling depends to a great extent upon its purity. It is mainly diminished by lead and zinc, and on the contrary increased by platinum. * * * Platinum increases the rapidity of evaporation if digested for one or two days with mercurv at a temperature of 50° to 80° C. Iridium, gold, silver, copper, nickel, cadmium and arsenic have no influence upon the rapidity of evaporation. ******* "Pure mercury is unchanged in air at the ordinary temperature, neither is it affected by long-continued agitation with air, oxygen, nitrous oxide, nitric oxide, or carbon tlioxide. In damp air, however, it gradually becomes coated with a thin film of mercurous oxide (HgiO). Impure mercur.\- becomes coated with a film of oxide even in dry air. If mercur>' is heated for a considerable time up to 350° C. in the air, it oxidizes to mercuric oxide (HgO), which, according to Pelouze, is crystalline. This gradually decomposes in the sunlight into mercury and oxygen." Mercury is solulile in concentiated boiling H„SO.i, but not in dilute. Insoluble in HCl ; solution in HNO;., even dilute; Soluble in a(iua regia, forming HgCU ******* "Sulphide of mercury (HgS) * * * ean be produced as an amorphous black mass by rubbing together flowers of sulphur and mercury and by gently heating the mixture of the two bodies. If this mass is heated to its melting point, mercuric sulpliide volitilizes and may lie condensed in tlie form of a brownish red crystalline sublimate. Tliis on grinding becomes scarlet and forms artificial cinnabar. When gently heated, air being excluded, it is readily reconverted into black amorphous mercuric sulphide, but if heated more strongly, it again sublimes as red sulphide. Native cinnabar begins to dai-ken at 200° C, and to volatilize; at 350° it volatilizes to a very great extent, but for its complete volatilization a low red heat 500° to 600° C. is requiied. With excess of air, it burns at 350° C. with a blue flame of sulphur, forming sulphur dioxide, metallic mercury separating out and volatilizing. The red sulphide of meicury daikens under the action of light,' and after a consid- erable lime it Ix-comes black in consi'(iuence of the separation of free mercury.'* * ♦ * When heated with other metals which jiossess a greater affinity for sulphur than mercury, for example with iron, tin or antimony, the mercury is liberated in the form of vapour, whilst the sulpluu- combines with the respective metals. * * « (This is made use of in the distillatir!l. '"EK-Ipston, T., Metallurgy of Silver, Gold and Mercury in the United State.s. Vol. II. 1800, pp. 79!)-!»01. "I-'orstner William, Quiok.'silver Rosource.=! of OaliCorni.T : Cal. State Mmms Kur. Bull. 27. p. 201, l!t03. QUICKSILVER RESOURCES. 211 PLATE XXIII. PIPF] RETORT FLRNACF] BY CEO. V. NORTHEY /fe/or7 (6" CO. sit iror? wafer p/p<^) ^' pipe. PLATE XXIV. waTey hushin, \Nith '/a drill&d co/lccfiyjQ TomH Plan of water-jet condenser for quicksilver retort at Oat Hill mine, Napa County. 212 CALIFORNIA STATE MINING BUREAU. "By using arches around the pipo spaces, each retort can be taken out separately without interfering witli the working of the others. Each retort has a separate niercur.v outlet, allowing opportunit.v to judge about its workings, and the water circulation thi'ougji each water jacket can he regulated separately. The firebox is placed to the side of the fust retort, instead of under it, enabling the easy discharging and charging of this retort. By placing the door of the retort inside the wall, cooling of the space against the door and consequent accumulation of mercury at that point are prevented. The charge is from 75 to 80 pounds of concentrates per shift, with the necessary lime, against 150 pounds of raw ore. Two furnace men are required — one per shift. "The expenses of this plant are about $25 per day for labor, '=fuel, repairs, etc. The 10-pipe retort, with suitable ore, can handle the total product of the concen- trating mill, running day and night, concentrating from 20 to 24 tons. The total cost of the plant, not including the mill building, is appro.ximately : 25 h.p. engine -- $1,000 Rock crusher 250 5-foot Huntington mill 1,500 5 bumping tables -_ 1,000 Concentrating table 500 1 elevator 100 Fittings, pipe, etc 150 Contingent expenses 500 1 pipe retort, with building and drier. 'This plant in three months turned out 330 flasks of mercury." $5,000 2,000 $7,000 Photo No. 41. 'D' retorts at Aetna Mine, Napa County. The 'T' of 1" pipe at retort door is the inlet for air circulation. Water-wheel and fan are at right, just out of picture. The 10-inch pipe retorts are usually 9 feet in length, and the 12-inch, 7 feet in length, the capacity thus varying from 4.9 to 5.5 cu. ft. In the usual practice the retort is not completely filled with ore, so that a "That was in 1903. QUICKSILVER RESOURCES. 213 supply of free oxygen will be present to vniite with the sulphur driven oft* and prevent its reuniting with the vaporized mercury. In some instances an air circulation has been provided, particularly in liandling concentrates. This was done with a water jet by R. P. Xewcomb at Oat Hill, Napa County, the arrangement being described by the writer^^ in a recent report on the mines of that county (see Plate XXIV). Another arrangement for aceompliishing the same pur- pose is that adopted with the 'D' retorts at the ^Etna Mine, Napa County. (See Photo No. 41.) A 1-inch iron pipe is fitted into the >"?«••',,,/' ^oJS'gmi^sr'^'"' ■ "-* Photo No. 42. Johnson-McKay retort, showing circulation system. door of the retort, and extends nearly to the back end of the interior. The exit pipe leads out from the side, just back of the door. In draw- ing oif the burned ore and also while filling the retort with a fresh charge, the exit pipe is kept clear by inserting a plug in the opening. A fan in the condenser system, driven by a small water-wheel, main- tains the draft through the retort. Both ore and concentrates were treated in these Aetna retorts. The Johnson-McKay pipe retorts have a special arrangement of fiues (see Photo No. 42), by which the portions of the pipe near the front and back ends receive the greater part of the heat. The following '■■■Braclley, W. W., Mines and Mineral Res. of Colusa, et al. Counties ; Cal. State Min. Bur. chapters of State Mineralogist's Report, 1913-1914, p. 117, 1915; also in State Mineralogist's Report XIV, p. 289, 1916. 2.U CAT.IFORNIA STATE MINING BUREAU. statciiu'iil is riirnished hy the manufacturers/* the Josluia Hendy Iron AVoi-ks. San Francisco: Photo No. 43. Charging a Johnson-McKay retort at the Patriquin Mine, Monterey County. "The Johnson-McKay furnace consists of a diani. A less number of pipes may be used if desired. Also be made 10 in. diam., but tlie standard size of furnace is bettei-. standard furnace consists of the following: 12 cast-iron retort pipes, 12 in. diam. by 6 ft. 14 cast-iron inside covers, iron outside covers, iron condenser pipes, 3 in. by S ft. ii'on furnace front with anchor bolts. battery of 12 retort pipes, each 12 in. the retort pipes can The ironwork for the in. long'. 12 12 1 1 cast- CilSt- cast- cast- cast- iron stack-plate. "Necessary frame rods, scrapers and chargers "The approximate weiglit Is tlie following list of bricks, lime, 6000 common I'od brick. 1300 common fire-brick. 200 arch flre-l)rick. 10 bl)Is. lime. 1 bbl. cement. 3J cu. yds. sand. 2 sacks fire-clay are 9100 lbs. For the cement and iumbei also supplied, setting of the standard furnace will be required : 12 6 2 3 2 "Any pieces pieces pieces pieces pieces pieces number 4 by 6 in. by 7 ft. 4 by 6 in. l)v 3 ft. 2 by 6 in. by 6 ft. 2 by 12 in. by 16 2 by 12 in. by 16 1 by 12 in. by 16 of pipes could be 5 in. Oregon pine for frame. 6 in. Oregon pine for frame. 8 in. Oregon pine for frame. ft. Oregon pine for frame, ft. Oregon pine for trough, ft. Oregon pine for trough, used, l)ut one could not operate so economically with a few pipes as with the standai-d equipment. Based on a 12-liour roasting period for each charge of ore, tlie operation of tlie standard fiu'nace is continuous, since one pipe is unload(^d and re-charged every hour. Wlien tlie pipes are suttirii'iitly lieated, the first pipe is cliarged, ;iiid tlien one pipe every consecutive liour until all have been charged. Hy that time I lie ore in tlie first jiipc' will liave roasted 12 hours, at the end of wliicli period it is ready for unloading and a fresh charge put in its place. At tlie end of the next hour, the second pipe would be unloaded and re-charged, and so on indefinitely. '^Min. & Sci. Press, Sept. 8. 19i: adv. QUICKSILVER RESOURCES. 215 "As the ore is heated the quicksilver volatilizes and thus separates from the sangue. It tlien passes to the condenser-pipes, and thence the condensed mercury drains to the water-filled troush at the rear of the furnace, where it is collected. Tlie cycle of operations destril)cd is based on a li'-hour roasting period for each charge of ore, but the length of the roasting period may vary. That depends on the character of the ore, the intensity of the heat maintained in the furnace, the expei-ienc(» of the attendant, and other factors. The standard size of furnace should treat from :2 to 5 tons daily. Some users have treated as many as 7 tons per 24 hours. Using wood for fuel, the consumption is from l?, to IJ cords per day." In l!)l(j. the iron-work for a battery of these retorts cost $840 f. o. b. San Francisco; while in October, 1917, the same material cost $950. On the basis of the 1916 prices, it cost approximately $2500 to $3000 to bnild snch a furnace nnder average conditions. The figures will var\- \\ith local conditions. Photo No. 44. A battery (12 pipes) of Johnson-McKay retorts at the Klau mine, San Luis Obispo County. Retorts are, of necessity from their construction, limited in capacity and require more labor to treat a given tonnage than do shaft furnaces. For these reasons they can be profitably used only for relatively high- grade ores and concentrates. From the standpoint of the life of the mine, it is doubtful economy in most cases to use them, as one must gouge the high-grade ore for them. Some attempts have been made to develop a continuous-feed retort. 216 CALIFORNIA STATE MINING BUREAU. The Fitzgerald furnace, a continuous-feed, inclined retort, was described bv Forstner:'^ -. -i - Photo No. 45. Livingston Furnace under construction at La Joya Mine, Napa County. "This furnace consists of an inclined, arched cliannel of fire-brick (angle 35°) With a tile floor. It has a charging hopper at the upper end and a discharge chamber with door at tlu' lower end. The Hames from the tire chamber pass tinder this ore chamber along two center flues, return along two otitside flues, pass to the top of the arch of the lower end, and go from the upper end to the smoke-stack. The vapors from the ore chamber are conducted through an iron exit pipe which is placed near the upper end of the ore chamber ;ind is water-jacketed outside of the furnace, to two condensers. In the second condenser an air current for exhaust is created by a water spra.v under 100 feet pressure, working on limestone to catch the flour mercury. The capacity of eacli chamber is rated at 10 tons per 24 hours, using one cord of pine wood. In practice the cajoacity is less." At the time of Forstncr's report (1903), three of these furnaces had recently been built in California, but at the present time, so far as the writer knows, there are none in operation in the State. "Forstner, Wm., Quicksilver Resources of California ; Cfil. State Min. Bur., Bull. 27, pp. 204, 205, 1903. QUICKSILVER RESOURCES. 217 A recently patented furnace of the continuous-feed retort type is known as the Livingston, having been patented by Mr. A. W. Livingston of Oakland, Cal. It consists of two vertical chambers with walls of thin fine-brick, and the fire on the outside. One such furnace was built in 1916 at the Esperanza Mine near Cloverdale, Sonoma County, but only a small amount of rock put through it, principally liecause the furnace was erected before the mine was ready to supply it with ore. More recently a second one has been built, at the La Joya mine (Photo No. 45) near Oakville, Napa County; and was just being dried out at the time of the writer's visit in September, 1917. A water spray in the vertical, condenser pipes (seen on the outside of the furnace wall) creates a draft to draw the fumes into the condensers and prevent their escape through the upper part of the ore charge to the outside. A special discharge hopper and door are a part of the design. Since the mine was visited, the writer is informed that this furnace has been discarded after a trial run on ore. One diflficulty appears to be that the furnace is not high enough, resulting in there not being a sufficient depth of charge to keep hot ore in contact with the mercurial vapors until they pass out by the exit pipe. There is also insufficient draft in the condensing system to completely pull the fumes from the ore chamber. The result of these two defects is that the quicksilver volatilized near the bottom of the ore chamber, con- denses upon the cold ore in the upper part before reaching the fume exit. The water-spray in the condenser has a tendency to flour the mercury. At the Bella Union mine, also near Oakville, the Rutherford Mining Co. was, when visited (September, 1917), building yet another arrangement of a 'continuous-feed retort', recently patented by their superintendent, Mr. E. E. Lillard. This consists of a circular, cast-iron ore chamber (the retort proper) set vertically, within the fire-box. It is two feet inside diameter, about 25 feet high, and has interior pro- jecting baffles cast with the shell, which is cast in three pieces to facil- itate installation. There is a discharge door arrangement at the bot- tom and a flue connection near the top to lead off the mercurial vapor to the condensers which will have a draft circulation. In 1916, at the Senator mine of the New Almaden company, a Lander's quicksilver retort, a special form of continuous-feed retort built by the Pacific Foundry Co., San Francisco, was installed to handle concentrates (see Plate XXV). It is stated to have given satisfactory results. As described by the manufacturers:^*' "The capacity of this retort is from 100 to 200 lbs. per hour, the inside diameter being 12" and the length approximately 12'. ""Personal letter to the author. 218 CALIFORNIA STATE MIXING BUREAU PLATE XXV. >^ 5s Lander's Continuous Retort. "The iron, work for this retort at the present time [Nov. 1, 1917] is worth approximately $1200. The general plan of operation is that the ore is fed into hopper #9 where it automatically seals the retort. The conveyor screw #15 which is mounted on an air-cooled shaft moves the ore forward where it is discharged through outlet Jf20. An auto- matically closing gate #21 prevents the inlet of air to the retort. Out- let #22 is for purpose of taking off the mercury vapors to a standard type of condenser. #25 indicates a fan which is to force air through the hollow shaft to the conveyor and which is for the purpose of keep- ing this part cool so that it will not warp on account of the heat of the retort. ' ' This retort could also be used to treat limited tonnages of high-grade ore at a small mine, where only a small amount of capital is available for equipment. The Whitton furnace, invented by W. W. Whittoii, Oakland, Cal., (U. S. Pat. #1,222,251, Apr. 10, 1917) is a multiple, vertical, continuous- feed retort, consisting of a series of any desired number of pipes from 4 to 17, arranged with a draft circulation to a condenser manifold. The 17-tube furnace is estimated to have a capacity of 25 tons per day, and to cost from $G,000 to $8,000 installed. The Pevear furnace has been developed by Waldo S. Pevear, #315^ W. 2d St., Los Angeles, Cal., patent for which, the writer understands, is now ])cing ai)plied for. It consists of a series of revolving circular, cast-iron chainlx'is willi interior-projecting lugs or teeth like the old- PLATE XXVI. IRON CLAD SHAFT FURNACE 'CONTINUOUS) SECTION A B. Sv^ tLEVATION h HORIZONTAL SECTIONS. Kxeli Furnace. 220 CALIFORNIA STATE MINING BUREAU. fashioned thrashing--machine cylinders. It requires that the ore be crushed as fine as 10 to 20 mesh. On such material, a practically com- plete distillation of the mercury is claimed in a very short roasting period. COARSE-ORE FURNACES. Coarse-ore furnaces, as the name indicates, arc built to treat coarse or lump ore. In construction and method of operation they are sim- ilar to an ordinary, vertical-shaft, lime kiln, and the ore as fed to them may vary from 3" to 9" in size. The principal varieties of this type of quicksilver furnace, which have been used to any extent are the Exeli, Knox-Osborne, Neate, and New Idria. Some fine ore can be, and at times is, charged with the lump ore ; but it should be done sparingly, as it would otherwise choke up the spaces between the ore chunks and prevent circulation of the products of fuel combustion. The addition of any fine ore is apt to materially reduce the capacity of a coarse-ore furnace. The Exeli furnace was first built at Idria, Austria, in 1871, by Bergrath A. Exeli. In California, two of them were built at New Almaden in 1874-1875, and have been in use until quite recently ; in fact are still in working order. The accompanying cut, (Plate XXVI) shows the construction of the Exeli furnace. Forstner^' describing these furnaces at New Almaden in 1903, says they were "treating 12 tons of ore every 24 hours; the ore remains 48 hours in the furnace. WTiile it is generally taken for granted that ores carrying a great amount of metallic mercury can not well be handled in shaft furnaces, these two furnaces in former years gave very satisfactory results when burning the ore from the 1500 foot level. Randol shaft, which contained large quantities of native mercury. The charge consists of about 1600 pounds of ore. These two furnaces require two men per shift and burn 0.605 cord of wood per 24 hours. The cost of treatment per ton is: Labor 10.4166 Fuel 0.3025 Total $0.7191" The Knox-Osborne coarse-ore furnace was patented in 1872, and at one time several of them were in use in California. There is one at the Manhattan mine, Knoxville, Napa County, though at present idle; and one in operation at the Culver-Baer mine, near Cloverdale, Sonoma County. "The cubic content of the furnaces is about 75 tons, and as it handles about 24 tons per day, the ore remains about three days in the furnace. The wood consumption on coarse ore is from 1 to li cords of oak per 24 hours. Three men per shift are required."'* The Neate coarse-ore furnace, patented by John Neate, is dis- tinguished from other furnaces of this type by its having no separate fire-box. (See Plate XXVIII.) "Cal. State Min. Bur. Bull. 27, p. 208. '-Idem, p. 210. > H < Hi C yy^^^^^^^^^m^ir^^^.Z i^'Vi'M''riVlii?TM'i"Vi'i i1'i 1 L n ^ : V 1 !f » — 1 r* • ^'i mj_iMj .[ Jx.U4.^^ 3 J J I.I JJ I I M.I .1,1 I J. I I TTl- '■ I I I ! I y-r-rrrTTT-n ] i i i i i i i i 222 CALIFORNIA STATE MINING BUREAU. PLATE XXVIII. ^rasA Charging Hopper \\\\\\\\\\\VS.' .V \W Iga^x^? frac^ V ^ ^d /^or p'afe //cor Discharging Forh and Door. COARSE ORB FURNACE. JOHN NEATE PAT. fiPMach compartment at tlie level of the top of the fire chambers, and is '"Cal. .State Min. Bur., Bull. 27. p. 210. =«Op. cit. p. 213. 224 CALIFORNIA STATE MINING BUREAU. X w < lQu; -h>— -rH — C^^^l V > 1 >:]ct II V- J •= ■^ 1 ~s J -«. ~) c ^ QUICKSILVER RESOURCES. 225 heated at three sides, while besides, as it comes into the fire cliambers, the cliarge spreads, thus causing its speedy heating to tlie liighest temperature in tlie furnace. The deptli of tlie discharge doors below the level of the tire chamber gives the ore a chance to cool off, and to give off tlie mercury vapors not volatilized during its passage in front of tlie tire chamber. This furnace is 17 feet wide, 24 feet through at the level of the fii-e cliaiubcr, and has a total height ot ilh feet from drawing floor to charging track. It handles from 90 to 100 tons per 24 hours; its cubic capacity is 2400 feet, hence the ore remains a little above 24 hours in the furnace. It is run by two shifts-' of five men ea(-li — one furnace man, two chargers, and two drawers — and requires not quite 21 cords of wood per day.=- The excessively low fuel consump- tion is partly due to tlie high [ ?] percentage of iron sulphide in the ore." There are two of these furnaces in operation at New Idria — #2 and #3. Their output is 25,000 to 30,000 tons of ore each per year, which they would handle at approximately $0.45 per ton, before the war; this figure including only direct furnace operation items, of labor, fuel, supplie."^. and soot treatment. Top losses from coarse-ore furnaces. While in the case of a fine-ore furnace like the Scott the fine material in the throat and hopper serves as an efi'ective top seal, in the coarse- ore furnaces some other means must be provided to prevent the escape of fumes from the top of the charge. Unless care be used, particularly during charging, the workman is liable to become salivated. An effec- tive form of seal is that employed with the Exeli furnace (see Plate XXVI. ante). Observations of Dr. Duschak on coarse-ore furnace operations are summarized in the following notes: "Temperature distribution. "The following temperatures were observed in a coarse-ore furnace at New Idria treating 60 to 80 tons, oil being used as fuel: ■"J Fire box . 900^ to 1,000^ C Ore in shaft at level of top of fire-box 550" to 600° C Exit pipe gases 180= to 200° C "Gas leakage. "Drafts are usually so regulated that pressure in exces.s of atmos- pheric exists in the upper part of the furnace. There is, therefore, a tendency for the escape of furnace gases resulting not only in the loss of mercury vapor, but also in exposing workmen to the danger of mer- curial poisoning, a condition which favors a neglect of the furnace by the attendants. In contrast to the Scott fine-ore furnace, the coarse ore in the charge hopper is of little use in sealing the top of the shaft. It is. therefore, necessary to provide such devices as accurately fitting slide gates and water-sealed hopper covers to avoid gas leakage. "On one occasion when gas leakage about the to]) of the furnace was particularly troublesome the introduction cf an i" air jet with 60 to -'In 1917, three shifts. "Crude oil is now used. 15—38540 226 CALIFORNIA STATE MINING BUREAU. 70 pounds air pressure in each of the two furnace exit pipes, together with the ]o\v(M-inL;' of the or(> enluiiin in the furnaee. fireatly rerlneed the (liftieulty. "The proportion of fine ore in tiie furnaee eliarS. -'Cal. State Min. Bur., The quicksilver industry of Italy : Min. Ind., vol. VI, Bull. 27, p. 215. X X X w H < u o c 3 V. o II 0) c 1- o o o c QUICKSILVER RESOURCES. 220 Till' Livermore furnace (see Plate XXXI) lias been described in detail by Egieston.-^ It is essentially an inclined-hearth furnace, with the products of fuel combustion pasing directly over the ore. So far as noted, there are but two examples of this furnace remaining in Califor- nia. One, a modified form, is in operation at the Cloverdale mine, near Cloverdale, Sonoma County. (See Photo No. 47.) Formerly wood » Photo No. 49. Side view of 50-ton Scott Furnace at Oceanic Mine, San Luis Obispo County. was used for fuel, but at present, crude oil. The burner being used is a Ray electric, (see Photo No. 48) in which the oil is atomized by a cur- rent of air created by an electric fan, the driving motor being direct- connected, and all self-contained in a single housing for each unit. The other furnace of the Livermore tyi)e is at the La Joya mine, near Oak- "Egle.ston, T., The Metallurgy of Silver, Gold and Mercury in the U. S.. Vol. II, p. 887, 1890. 230 CALIFORNIA STATE MINING BUREAU. PLATE XXXI _jrmr ni/ii»>js/- Sri„ng:s'SZ- ^^^^^^ IZG o / p 3 ^ s Plan & Secfion of LIVERMORE FURNACE Unc^er ftr^ppe fo c/i^77n^y ■^X ■X'.X.^- QUICKSILVER RESOURCES. 231 •c PLATE XXXII. it fy Pimta S-*^ ar^M^at 5hr^-^'-^ QUICKSILVER RESOURCES. 231 ville, Xapa County, and was in operation during- a part of 1916 and 1917. This furnace, as originally built, was supposed to lie a Fitzger- ald-** inclined retort ; but it appeared to the writer to have been oper- ated like a Livermore, with the flames from the fuel passing directly up the ore chamber instead of around it. It is now idle, having been sup- planted by retorts. The Hiittner-Scott furnace, (now generally referred to as the Scott), was developed by H. J. Hiittner, Robert Scott and J. B. Randol in 1875-1876 at the New Almaden mine,-" Santa Clara County, as an improvement on the earlier, European, Hasenclever furnace, to treat the 'tierras' or fine ore which had previously been molded into adobes before burning. The opening, or shelf-slit, between the edge of one tile and the face of the one next below it was originally set at 3 inches. This has been widened in later furnaces, up to as much as, 8 inches (usually 5" or 6"), so that medium-sized ore up to say 3^ inches may now be treated in these furnaces. As will be not^d from Plate XXXII, the tiles form a zig-zag channel for the passage of the ore as it moves from the top to the bottom of the ore chamber. The tiles generally used are flat, being 3" x 15" x 36" in size. Accord- ing to Forstner,-^ in 1903 they were imported and cost, laid down in San Francisco, $3.50 apiece. More recently some have been made by certain California fire-brick and pottery manufacturers, and are reported to be giving satisfactory service. These cost approximately $3 apiece, f.o.b. shipping point. In some cases, as in Furnace No. 3 at New Almaden-'' and the Cermak-Spirek-'* furnace used in Europe, a special form of tile is used; but the same zig-zag channel effect for the ore is obtained, while the tile is stated not to have given as satisfactory .service as the flat form. The fire-box of the Scott furnace is on one side of the ore chamber, and a vapor chamber on the opposite side. The furnaces are built in daily capacities of from 10 to 60 tons. The capacity is governed by the number, length, and height of the ore chamber.s — -each additional tile increasing the length of the chamber by 36 inches, and the height vary- ing with the number of tiles placed one above the other. Usually the outer walls are braced with iron tie-rods. (See Photo No. 49.) Two of the furnaces at New Almaden were ' iron-clads ', or enclosed with iron plates ; but this appears unnecessarily expensive. Peep holes are placed in the end walls, to enable observation of the condition of the ore at different levels in the furnace. ='For.stner, Wm., Quicksilver Resources of California: Cal. State Min. Bur. Bull. 27, p. 81, 190.3. -•Christy, S. B., Quirksilver Reduction at New Almaden : Trans. Am. Inst. Min. Eng.. Vol. XIII, p. .^5.3. 18S.5. =»State Min. Bur. Bull. 27. p. 221. ^Iflem. p. 221. i T-T-. TlTTXTTXTn RTTRTTATT. I QUICKSILVER RESOURCES. 231 ville, Napa County, and was in operation durinji' a part of ]916 and 1917. This furnace, as originally built, was supposed to be a Fitzger- ald'-'' inclined retort ; but it appeared to the writer to have been oper- ated like a Livermore, with the flames from the fuel passing directly up the ore chamber instead of arovmd it. It is now idle, having been sup- planted by retorts. The Hiittner-Scott furnace, (now generally referred to as the Seott), was developed by H. J. ITiittner, Robert Scott and J. B. Randol in 1875-1876 at the New Almaden mine,"^ Santa Clara County, as an improvement on the earlier, European, Hasenclever furnace, to treat the 'tierras' or fine ore which had previously been molded into adobes before burning. The opening, or shelf-slit, between the edge of one tile and the face of the one next below it was originally set at 3 inches. I This has been widened in later furnaces, up to as much as 8 inches (usually 5" or 6"), so that medium-sized ore up to say 3^ inches may now be treated in these furnaces. As will be not^d from Plate XXXII, the tiles form a zig-zag channel for the passage of the ore as it moves from the top to the bottom of the ore chamber. The tiles generally used are flat, being 3" x 15" x 36" in size. Accord- ing to Forstner,-^ in 1903 they were imported and cost, laid down in San Francisco, $3.50 apiece. More recently some have been made by certain California fire-brick and pottery manufacturers, and are reported to be giving satisfactory service. These cost approximately $3 apiece, f.o.b. shipping point. In some cases, as in Furnace No. 3 at New Almaden-^ and the Cermak-Spirek-" furnace used in Europe, a special form of tile is used; but the same zig-zag channel effect for the ore is obtained, while the tile is stated not to have given as satisfactory service as the flat form. The fire-box of the Scott furnace is on one side of the ore chamber, and a vapor chamber on the opposite side. The furnaces are built in daily capacities of from 10 to 60 tons. The capacity is governed by the number, length, and height of the ore chamber.s — each additional tile increasing the length of the chamber by 36 inches, and the height vary- ing with the number of tiles placed one above the other. Usually the outer walls are braced with iron tie-rods. (See Photo No. 49.) Two of tiie furnaces at New Almaden were 'iron-clads', or enclosed with iron plates ; but this appears unnecessarily expensive. Peep holes are placed in the end walls, to enable observation of the condition of the ore at different levels in the furnace. =«For.';tner. Wm., Quicksilver Resources of California: Cal. State Min. Bur. Bull. 27, p. 81, 1903. "Christy, S. B., Quicksilver Reduction at New Almaden : Tians. Am. Inst. Min. JSng., Vol. XIII, p. !S.^3. 188.5. "State Min. Bur. Bull. 27. p. 221. ^Idem. p. 221. 232 CALIFORNIA STATE MINING BUREAU. (}' p ■J. o a. o H QUICKSILVER RESOURCES. 233 PLATE XXXIV. Discharge of Scott Furnace. The charging and discharging arrangements for the Scott furnace are shown by Plates XXXIII and XXXIV, also Photo No. 4, {ante). The following two tabulations by Forstner^^ give the dimensions of >;»me of the Scott furnaces in California in 1903 and the materials required in construction : "Op. cit. p. 223. 234: CALIFORNIA STA'I'K MIXIXC BUREAl'. O) +J 60 CO O t. o S a >> c ^ c 4J O O O ^ spjOD tM(M T-Hi-H !M ■^iN W«l<-^ jeqmnij V o (8 C 3 E o W c re re Q laaj 'aS.iBqasip JO luiod 0} jooj uiojj in3i3H t^ 1^ CO O OS --I (M (M CO rC(M 00 COOO lO TOCO CO saqoni 'ms Jiaqg saqoni 'qjpiAV irtio - (MOOOO J39J 'mSusq 599J 'SAOqH aq3l3q iBjoi o * -a< CO CO (M(N (MCOIN \^ IC 1-1 05CO (M 1-1 COCO »o CO C=) o COOO CO T-l 00(MCE go Q O O O lO CO CO CO "^ CO »-H o rf a a o 05 E is o o coco G . . c o c -^ G a c ;::; c-^iw QUICKSILVER RESOURCES. Materials Required for a Scott Furnace. 235 10-ton 40-ton 50-ton ^ , . 1 ' 150,000 300,000 400,000 Common brick ^2000 20,000 30,000 Fire brick '^gg 36O 428 Tiles ...--—— 25 1 40 50 Cement (barrels) ! I Fire-clay, timber for frame, iron for frame, grates, hopper, etc. The common brick are frequently burned from local clays near the mine Fire-brick in 1903 cost $32.50 per 1000 in San Francisco ; while in 1917 they were approximately $30-$40 per 1000 depending on quan- titv bousht. . , , . T J The total cost of a Scott furnace, complete, with brick condensers, will amount to approximately $1000 per ton-day capacity. Some have been built for less, and the cost will vary with freight rates, labor, avail- ability of local clays for brick, and other local conditions. Wi h wooden condensers, instead of brick, the plant cost will be appreciably lowered Present economic conditions are abnormal to such a degree, that any cost data given as of the moment, would not represent a fair basis for comparison. 114- The Scott furnace could be built with thinner walls, with an msulat- inc. laver such as diatomaceous-earth blocks between the outer brick ana the fire-brick lining. To strengthen these lighter walls, they could be iron-clad, but it need not be so heavy as were the iron-clad furnaces at the New Almaden mine. The insulating layer would reduce loss of heat by radiation, and thus economize on fuel consumption. \mon- other things, there is one feature of Scott furnace operations which has impressed itself upon the writer -.-that is, the number of times that the ore is handled at many of the plants before it is finally discarded. Nor is this an unu.sual fault nor confined to the quicksilver mines. It is of frequent occurrence at many other kinds of mines, till the ore '^ets 'worn-out' with handling, as the saying goes. An auto- matic ieed could be readily provided for a Scott furnace. In fact, there is oae si.ch installation, at least, in California, at the Guadalupe mine, Santa Clara County.* The ore from the bins is fed automatically to a rotarv drier which in curn discharges directly into the hopper of the Scott.' An automatic discharge would probably be more difficult to arrange, but it could doubtless be accomplished. Such features would materially reduce the labor item in the cost of operation. As ordinarily conducted, the roasting period of the ore in a Scott furnace is approximately 2-t hours— that is, 2-4 hours is the time 236 CALIFORNIA sTAi'i; :mixing bureau. required for a given cliarge to pass from the throat to the discharge pit. At the Black Butte IMiue. Oregon, in 3909, W. B. Dennis,''' developed an aece.^.sory wood-gas producer with a gas lieating arrangement for the 40-ton Scott furnace, by which he i-ednced the roasting period from 24 hours to 4 hours, "with a cleaner and in every way more satisfactory roast." We have not heard of this system having been adopted else- where, at least not in Calif(U'nia ; hut it would appear to merit invcsti- gal ion. In the high temperature parts of the furnace, wherever there is a dead space due to a corner or lack of draft (as in the square corner.s of the flues and dust chambers), the SO^ and volatilized mercury unite to form a deposit of mercuric sulphate scale. The author has specimens of such material which were gathered from furnaces being torn down at the Sulphur Bank mine, and at New Idria. Goodyear^^^ describes the formation of sulphate in the furnaces at New Idria and notes that more of it formed in the summer months, than in the winter. Observations of Dr. Duschak relative to temperature distribution and regulation, and fuel consumption, in the Scott furnace, are summarized in the following statements : "Temperature distribution. "Both wood and fuel-oil are used in the Scott furnace in California. The range and distribution of the temperature in the furnace varies somewhat with the fuel, and the distribution also depends on Avhether an auxiliary fire is used at the back of the furnace in the chamber oppo- site the main fire box. This point will be made clear by reference to the accompanying diagram (Plate XXXV) which represents a vertical cross-section parallel to the side of the furnace. The hot gases from the main fire-box 1, have a tendency to rise to the arch and seek passage through the upper rows of flues, thus leaving the lower part of the furnace, particularly at the rear, in the vicinity of 2, relatively cold. When, however, a small fire is introduced at 2 a draft is created which tends to draw the gases from the main fire-box through the lower flues thereby making the lower portion of the furnace more effective. In the following tabulation, column A shows the range of temperatures in a wood-fired 50-ton Scott furnace without auxiliary fire at 2. Column B gives similar data for an oil-fired 70-ton Scott furnace with a small fire at 2. The numbers refer to tlie accompanying diagram. (Plate XXXV.) "Dennis, W. B., Shortenins the roasting' period for mercury ores: Eng. & Min. Jour., Vol. LXXXVIII, pp. 112-116, 1900. ''"Goodyear, W. A., Report on examination of tlie Quicksilver minr.s of California : Geol. Surv. of Cal., Geol. Vol. II. pp. 116, 117, 1SS2. QUICKSILVER RESOURCES. 237 700^^ to 900° C 3. 500° to 550° C 4. 5. 6. i s 300° to 350° C 150° C B 900° to 1100° C 600° to 700° C 600° to 700° C 400° to 450° C 200° C "As is pointed out in succeeding paragraphs, the proper exit-pipe temperature varies with the grade of ore and the volume of gas leaving the furnace per ton of ore treated. Taking these points into consider- ation the exit-pipe temperatures shown in the above tabulation both represent safe practice. "Exit Pipe Temperature. "The temperature of the gases leaving a quicksilver furnace must be sufficient to prevent the condensation of any quicksilver in the furnace. On the other hand an excessive temperature means a waste of fuel and throws an unnecessary burden upon the condenser system. The tem- perature at which quicksilver vapor will begin to condense depends upon its concentration in the furnace gases which in turn depends upon the grade of ore and the volume of gases leaving the furnace per unit PLATE XXXV. SKETCH OF SCOTT FURNACE £nc/ Sect/on Burner Booster Fire SCALE OF FEET O — J I I ( J Mam Fire-box L ongit udinal Sec tion Co/ifor'ntaSfoteMiningBiJ'~^au 238 CALIFORNIA STATE MINING BUREAU. weight of ore treated. The rehition between these several factors is given by tin- curves in tlie at-eompanying diagram. (Plate XXXVI.) The tempera! ui't' at wliicli the fnrnace gas will be saturated with quick- silver vapor, or in otlici- words, below which condensation will begin, is given i»y tlie abscissa. The volume of furnace gas in cubic meters per metric ton of ore is plotted as ordinate and the several curves correspond to ores containing the indicated percentages of mercury. For ordinary Scott furnace practice the volume of gas measured at 0° C. and at the average atmospheric pressure at the furnace amounts to 400 to 700 cubic meters per metric ton of charge. PLATE XXXVI. >f B CONDENSATION TEMPERATURES FOR MERCURY VAPOR IN FURNACE GASES ^ jj "j4~i^opor pressure of /ryercary expressed /n mm. of mercury. 1 ^ "B"-Ky.o/mercury retfuired to saturate /rn'o/oir measured ot O'C. "^ ^ and tieoted under constant pressure to yivery temperature. 4 •§ //T}'-3S./4.fi. IOOOfrg.'ZZ04/bs 6 ^ m' furnace cfas at O'Cortd constant Cprey-a/Z/ng) pressure per /OOOAg.ore. J7.*7 /2.SS am 6.1?/ /MO /./9a 0.7Si9 0.46JS 0.l7ii 0.IS9? O.OS96 0.04e6 O.Oi54 O.OOI27 O.0OS99 0OO277 0.00/ZI aOj/s* Accompa 0.2/0 O./SO 0/05 0.073/ 0.0498 a0334 0X>2/9 0.0/4/ o.oo8as 0.00S4S 0.00324 0.00/88 aoo/os 0.0j S84 0.0,298 O.Oj /49 0.0,704 0.0^ 32$ 0*/42 O.0sS69 O.Os2/€ nymj 3u/ 200' /SO" /«o° /TO" /SO' /so' /40' /20' I/O' /oo' 90' so' 70' SO' SO' ■to' M' 20' /O' \. 1 (7% s O 8% \ ^ O. 6% S^ Sv ■^ ^ a 49i ^ N^ sj ^ ^ -, o P% s ^O"^ ^ ---. : 1 ^ S <^ ' :;:; -^— ~- ^ ^ ^ ■ — , — ^ ^■ p- 1 "i — ~ ^ - 5 F== ' ^ 3 2 ^ = = = Pd ; = = Lie. Ol OIL — — ^ — =1 ^ "~" = — ^ = =1 = = = 04 02. JL i /et/n A ? /OO zoo 30Q -^OO SOQ 600 TOO <900 900 /OOC //OO /200 /JOO /400 /SO^ /600 /''C'O ,800 a7i9. Co/t/t)r-n,a Stole /fining aareau Ca^riPSi/ of U5 /- -.■».. .-r'**' "'■J "By way of illustration assume that the furnace charge carries 0.8% Hg and that the gases leaving the furnace amount to 500 cubic meters measured under the above conditions per metric ton of charge. By reference to the chart it will be seen that the theoretical saturation tem- perature is about 134° C. In practice, however, a certain margin of safety is necessary in order to make due allowance for normal tluctua- tions in furnace temperature and for the chilling of the gas when cold and damp ore enters the furnace. A temperature of 175° C. would be about right under the above conditions. At this temperature the gases leaving the furnace per metric ton charged would occupy a volume of 820 cubic meters (corresponding to 2(5,200 cubic feet per short ton). "Extending the practical illustration a little further, suppose that a furnace operating undo- the c(tndi1ions just assumed, handles 50 metric i P QUICKSILVER RESOURCES. 239 tous (55 short tons) of ore in 2-1: hours. At the exit-pipe temperature of 175° C, 28.5 cubie meters (1000 cubic feet) of gas will leave the furnace per minute. Assuming .that the gas stream increases 25% in volume through leakage in passing through the condenser system and leaves at 40" C. the mean linear velocity in the usual 3-foot diameter flue leading to the stack will be about 36 meters or 120 feet per minute. This will serve to give some idea of the conditions obtaining in good furnace practice. ' ' "Temperature regulation. "Quicksilver operators have not yet fully appreciated the advantages along the line of fuel economy and safer and more certain furnace oper- ation to be gained by careful temperature control. A suitable install- ation for this purpose consists of an indicating pyrometer, situated near the furnace for use of the furnace men. a recorder in the superintend- ent's office or at other convenient point, and preferably, at least two thermocouples in each furnace. By the use of suitable switches a single indicator and recorder can be used for several furnaces. "The location of the thermocouples requires some consideration. Referring to the diagram (Plate XXXV). although there would be some advantage in placing a thermocouple at point 1 in the main fire- box, the temperature range with oil firing at least is such that a base- metal couple is likely to undergo deterioration and thus render its indi- cation somewhat uncertain. Moreover, the advantage to be gained b.y permanently locating a couple at this point hardly justifies the high cost of a precious-metal couple. Point 3 is suggested as a good per- manent location for a .base-metal thermocouple and a second one may be advantageously placed in one of the exil> pipes (point 6). Regular observation of the temperatures at these two points should be sufficient for good regulation of the furnace, but it is suggested that an extra ^et of leads be provided from the indicator to the furnace so that a portable base metal couple may be used in making temperature observa- tions at points 1, 4 and 5 or elsewhere. With the usual Scott furnace construction certain peep holes may be selected for use in making a thorough survey of the furnace temperature. It is believed that such a survey should be particularly useful in locating the cause of any dis- turbance in regular furnace operation. "Fuel consumption. "With ore carrying only a few per cent uf moisture, but devoid of any considerable quantity of metal sulphides, which would serve as fuel, a fuel oil consumption of 5 to 6 gallons per ton of ore treated, or 240 CALIFORNIA STATE MINING BUREAU. roughly, 2.2% by weight, may Ix' considered as good practice. Witli wood as fuel the consumption ranges from 0.03 to 0.05 cords per ton, or roughly, 47r hy wfight, depending somewhat on Ihe quality of the wood. "A high moisture content in the furnace charge will not only increase the fuel consumption, but increase the danger of hang-ups and other disturbaiiees in furnace operations. When moist ore is to be handled it should be dried before charging to the furnace. A Scott furnace is not designed as an ore drier. Generally speaking, the evap- oration of a given amount of moisture calls for a given fuel consump- tion. There is therefore, no fuel economy in feeding wet ore to the furnace, but on the other hand, hang-ups resulting in the reduction of furnace capacity and other difficulties are likely to result. "Observations made in the field, recently, indicated that sufficient attention has not been given to the regulation of the air entering the Scott furnace. With oil firing under the best practice so far observed nearly 100% air in excess of that required for combustion leaves the furnace exit pipes and with wood firing an excess of 200% to 300%: has been observed. This excess not only increases the fuel consump- tion, but also throws an unnecessary burden on the condenser system. "The entrance of unnecessary air to the furnace can be controlled partially at least bj" suitable regulation at the fire door and other open- ings into the combustion chamber and also by careful luting about the peep holes, or any cracks in the furnace walls. Counterpoised gates for closing the openings through which the burnt rock is withdrawn may also assist in this direction. The object to he attained is to allow no air to enter the furnace except at the comhusiion chamber and tJiis in sufficient quantity to burn the fuel completehj but no more. The problem of burning wood efficiently closely re.sembles that of efficient use of bituminous coal in a boiler plant. The fuel should preferably be introduced frequently in small quantities and sufficient air admitted above the grate immediately after the addition of the fuel to bui"n the gases distilling from the wood. As the charing of the wood advances the air supply above the fire should be reduced and more air admitted below. It is recognized, owing to the variety of duties which the furnace attendant is usually called upon to perform, tliat it may l)e dif- ficult to approximate ideal fire-box conditions. Some ett'ort in tliis direction seems worth whil(\ however, as incomplete combustion with the attendant formation of carbonaceous soot not only favors the formation of mei'curial soot in the condenser but con.stitutes a waste of fuel. Objections to excess of air have been iin'iitioiird above." QUICKSILVER RESOURCES. 241 TOP LOSSES. In fine-ore furnaces of the Scott type, the fine material in the throat and hopper serves usually as an effective seal. This will vary some with the nature and dryness of the ore as well as the amount of really tine material in the mixture. However, the precaution should be observed of keeping the hopper full. The Innes fume trap as installed at the Oceanic mine is effective. This has been described, accompanied by a diagram, by Heberlein f- but it is now built with a single fume exit between and serving the two throats of each furnace, instead of an exit for each throat separately. Also, wood is used in the construction, instead of cast iron as there shown. This resembles an arrangement utilized at Idria, Austria, described by Castek.^^ Referring to this device at the Oceanic mine, Duschak observes that it is "probably useful also in removing water vapor which escapes from the ore as it descends the throat of the furnace, and which might otherwise condense in the cold upper layers of the charge, rendering the ore sticky and favoring hang-ups. "A study was made of the volume and mercury content of the gases escaping from the special condensing chamber attached to the fume trap of the newer of the two 50-ton Scott furnaces. The following data were obtained : ■ Average temperature of escaping gas, 30° C. Volume per minute at 30° C, 5 cu. meters (175 cu. ft.). Mercury loss per 24 hours, 0.25 kg. (0.55 lbs.)." ABSORPTION AND DISCHARGE LOSSES. With the Scott furnace, carefully operated, there should be practi- cally no values in the spent ore as discharged. With care,' it is a rela- tively simple matter to expel all of the quicksilver from the rock. If, however, the furnace be crowded and the heated rock drawn off too soon from below, there will be values remaining in it. If the rock be still hot enough for any remaining mercury to volatilize, such remaining metal might escape into the air, and an assay of the tailings might thereby indicate a clean 'extraction', though obviously not a clean recovery. That this is not only possible, but sometimes does occur, is showTi by the fact that the draw-man generally wears some sort of nose and throat protection, and sometimes they have been salivated, though not often. The investigations of the U. S. Bureau of Mines have shown the stack fume losses to be much smaller than it had been expected to fiiid them. '-Heberlein, C. A., The mining' and reduction of quicksilver ore at the Oceanic mine. Cambria, Cal. : Bull. Am. Inst. Min. Eng., Feb., 1915, p. 500. Also, in Trans., Vol. LI, p. 113. ■"Castek, Franz, Die Bestlmmung und Verminderung der Verluste beim Queck- silberhuttenwesen : Berg- u. Hiittenmannisches Jahrbuch, LVIII, Band. Wien, 1910. 16—38540 QUICKSILVER RESOURCES. 243 At New Idria. on 0.7% ore, the loss was but 4^ j)ounds of ({uicksilver per 24 hours treating 75 tons of ore. At the Oceanic mine, on 0.3% ore, it was 6^ pounds, treating 90 tons. Wliile top, stack, and discharge losses are controllable to a greater or less extent, there is one form of loss, that of absorption, which is impossible to measure and practically impossible to control where brick or stone are used in the construction of furnace and condenser walls. The Scott fine-ore furnace with its usual system of brick condensers is notorious for its hoarding up of absorbed quicksilver. Of course, it is not an ultimate loss, as it can some day be recovered by wrecking the plant ; but to all intents and pur- poses, as long as it remains there, it is a loss. One superintendent who still very much favors the Scott furnace recently made this observation to the "writer : "If you will take the recovery of absorbed mercury from the wrecking of a given plant, and divide it by the number of tons of ore which passed through that furnace during its service, you will find the percentage of the loss very small. The absorption in a new^ plant is considerable in the first three or four months of operation ; but after that it reaches a point of saturation." Any absorption is a loss, and therefore objectionable. Its extent will depend on the construction of the plant. Recent improvements in condenser construction, discussed under that heading, will minimize that loss. It seems to the writer that the point of saturation may often be a long time arriving, especially in view of the depth to which quicksilver has been found in the soil and earth under some plants. At the pres- ent time at New Almaden, they are recovering quicksilver to a depth of 30 feet under the site of certain of their old furnaces. The earth and gravel there are literally 'alive' with globules of the metal, as the accompanying photograph (No. 50) shows. A tunnel recently run under one of the furnaces at New Idria shows a similar condition to exist there While the percentage loss may be small as suggested above, tlie uncertainty of it is in the apparent inability to determine currently what it is or to control it. Here again enters the subject of technical control of operations, of which we have already mentioned the lack in quicksilver reduction in California. Without regular sampling and assaying, it is impossible to know what a plant is doing. COST OF OPERATING A SCOTT FURNACE. The costs of operating a Scott furnace plant will of course vary, as they will vary in any other metallurgical process, with local conditions, tonnage treated, and efficienc3^ Figures of from 50^ per ton to 75^ per ton have been given for plants of at least 50 tons daily capacity, working under favorable conditions and carefully managed. Smaller plants and those less favorably situated will cost more. These figures include only the day-to-day running expenses. They do not include any 244 CALIFORNIA STATE MINING BUREAU. item of interest, depreciation or amortization on the high initial install- ation capital, nor for repairs and general overhead charges. Figured conservatively these may total anywhere from 25^ to 50^ per ton. Material repairs should not be required oftener than about once in four or five years; but when they do come they are costly. At New Idria the lining in the coarse-ore furnaces usually lasts three years, and in the fine-ore, four years. It is usually not necessary to completely re-line, nor to replace all of the tiles. At the Oceanic mine, San Luis Obispo County, the direct operating costs as recorded by Logan^* in November, 1915, amounted to $0.57 per ton with a 50-ton furnace ; and were divided, as follows : 3 furnacemen @ $2.50 $7 50 3 chargemen @ $2.50 7 50 1 foreman 4 50 1 helper -- 2 00 1 cord pine wood, delivered 5 50 Estimated cost of soot treatment per ton of ore, $0.08 ; per day's run, 50 tons 1 50 Total cost for 50 tons $28 50 Present costs (September, 1917), as furnished the writer by ]Mr. Ellard W. Carson, now manager of the Oceanic INIine, show a material increase due mainly to advances in wages. There are now two 50-ton furnaces, treating an average total of 90 tons dailj^, and the items are distributed as follows : 3 furnacemen, each, i. e. 6 @ $3 $18 00 3 chargemen, each, i. e. 6 @ $3 18 00 1 foreman 5 00 1 helper 2 75 li cords, pine wood, each, i. e. 2i cords @. $6.50 10 2."> Soot, 90 T. @ $0.03 -' 2 70 Total cost for 90 tons $62 70 This gives a per-ton figure of $0,697, to which should be added the item of superintendence, at least, as the owner, Mr. Murray Innes, does not now personally supervise operations as in 1915. At the Cambria mine, San Luis Obispo County, in 1915, Carson^^ reported the following cost of operating a 50-ton Scott furnace : "Actual operating costs treating 50 tons per daj^ on a basis of a 30-day month, average us somewhat under $1000 per month, or 66|ff per ton This cost is distributed approximately as follows : "6 furnacemen @ $2.50 per day $450 Foreman and overhead 210 Total labor $000 Wood, li cords per day, @ $6 270 Miscellaneous supplies 70 $1,000 "LoRan. C. A., in Cal. State Mln. Bur., Report on Mines & Minerals of Monterej etc. counties, 1917, p. 124. "Personal correspondence with H. G. S. Anderson re comparative costs of a we method for quicksilver. QUICKSILVER RESOURCES. 245 "1500 tons of 10-poimd ore, with 90% extraction, would yii'ld 13,500 pounds of quicksilver at a cost of 7.44 cents per pound. * * * On a basis of a 100-ton plant treating ten-pound ore in a Scott furnace the cost of production should not exceed 8 cents per pound for the metallurgical treatment. * * *" In 1914, a certain Scott fine-ore furnace in California treated 22,000 tons of ore at a cost of $0,715 per ton. During a part of the year this furnace was idle Avhile being repaired; for in 1915, it handled 27,000 tons at a cost of $0,652 per ton. These figures include only the direct items for furnace operation, of labor, fuel, supplies, and soot treatment. PERCENTAGE OF EXTRACTION OBTAINED BY SCOTT FURNACES. Very few operators really know what their furnaces are actually doing, because of the absence of systematic sampling and assaying. Some of them will tell you that because of the erratic nature of most quicksilver deposits, it is quite impossible to accurately sample the ores. It should not be any more 'impossible' than on an ore carrying free gold occasionally, and that is done with fair precision, daily, in many local- ities. We will aclmowledge that it is a difficult matter to adequately and accurately sample the feed of a coarse-ore furnace, but it can be done ; while it should be a relatively simple matter for fine ore. ■ At the Cambria mine in 1915, as incidentally mentioned in the pre- ceding section under the heading of costs, Carson credits his plant with obtaining 90% extraction. At the present time, (October, 1917) at the Oceanic mine, his practice and results are : The head sample is a dip by hand with a small scoop from each bucket of the aerial tramway ju.st after loading at the upper terminal. The furnace reject is sampled by taking a shovel full from each third car. These samples are cpiar- tered down, once a week, and sent to an assaj'ing firm in San Fran- cisco. The heads are averaging 0.26% to 0.36% mercury, and the tail- ings 0.02% to 0.03%. This is an indicated extraction of 91.7%. It is to be noted that these heads assays are made on dry material, whereas the ore as it reaches the furnace carries from 8% to 10% moisture. At one other mine in California where sampling and assaying is at present being carried out, the Scott furnace heads for the month of July, 1917, averaged 0.66% mercury and the discharge 0.10%, or an indicated extraction of 84.8%. For the month of August, 1917, the heads averaged 0.61% Hg, and the tails 0.069% Hg, an indicated extrac- tion of 88.6%. This plant is ec^uipped with an electric, indicating pyrometer, so that a careful tab is kept on the furnace temperatures. At one mine in a western state outside of California, a 30-ton Scott furnace under careful supervision during a short period of operation in 1914, is stated to have shown an indicated extraction of 86% by assays of heads and tailings samples, on a 0.36% Hg ore. 246 CALIFORNIA STATE MINING BUREAU. These are all favorable cases, at well-eqnipped and carefully super- vised plants, and their results are undoul)tedly nnich better than the average. These figures, too. are indicated extractions, not cpiicksilver actually bottled. It is questionable if the average plant as ordinarily conducted in California for some years past, has been recovering 75% of the value in the ore. Egleston'"' in discussing this phase of quicksilver operations, says: "While the price of mercury was very high no assays of any kind were made at the mine. The superintendent of tlie works or tlie mines judged by 'experience' that tlie ore contained 1, 2, .3. 10, or 20 per cent., as tlie case might be. Tliere was conse- quently very little dependence to be placed upon any statements of the advocates of the different kinds of furnaces that their furnaces actually yielded a higher per- centage than tliose of their neighbours, or, in fact, that they yielded any given percentage at all. The only statement that could be relied upon was, that tliey pro- duce in twenty-four hours a given number of pounds of mercury." Also^'^ : "At New Almaden, after taking a sample fiom each car-load for thirty-nine days, they report their loss to be 7.29 per cent. The difficulty of sampling ores of mercury, and the probability of getting too low rather than too high an average, makes the loss appear much lower than it really is. "According to the best California authorities, the loss in the best constructed furnaces, as near as can be approximated, is not less than 15 to 20 per cent; and in many works the loss will probably amount to double that. In the best works it would probably cost more to save the 15 or 20 per cent loss than it is worth ; and the works which are not well managed probably could not save it at all." Christy, relative to condensation at New Almaden, in discussing losses of treatment, says v'^ "There is perhaps no subject on which greater differences of opinion exist, than upon the losses which occur in roasting quicksilver ores. These losses have been variously estimated by different persons at all the way from 50 per cent by pessimistic critics to 0.01 per cent by optimistic inventors. "Unfortunately for the purpose of this inquiry, it is not customary at New Almaden, or at any of the quicksilver mines of California, to take careful and systematic samples for assay, as is done at Idria, Austria. * * * "Furthermore, I have been unable to find, in the whole range of quicksilver litera- ture, any adequate determination of what must be the inferior limit of the losses on the plan of treatment selected. In other words, there is at present no criterion by which we may judge as to whether a given condensing system is doing the best that can be expected of it, or by which we can even approximately estimate the relative value of different systems." Nor has anyone seemed to try or to bother themselves much to improve furnace and condenser conditions on a systematic, .scientific basis since Christy's experiments at New Almaden, until the pre.-ieut investigations of the United States Bureau of Klines, herein recorded. Also, he concludes : "The loss [by 'vapor' and 'mist'] is dependent on the volume of fumes, at the same escape-temperature ; and the latter, of course, depends on the amount of fuel and ore used, and not on the riiMiness of the ore. Hence, the percentage-loss will be less on rich tlian on pooi- ore." * * * =""As a minimum net loss is the real objective point, this can be reached only by a careful adjustment of tliese conflicting losses (i.e., fume and residue). Thus, with a given furnace reducing 12 tons per 24 hoiu-s witji a residue loss of 0.5 per cent, and a chimney-loss of 10 per cent of the ore content, it would evidently be better to treat 24 tons per 24 hours with a residue loss of 1 per cent and a cliimney loss of 6 per cent of the ore content; for in tlie fii-st case, the losses would net 10.5 per cent, and in the latter, 7 per cent. Such adjustments, are, however, only possible where the ores and residues are systematically sampled and assayed." '"Kgleston, T., The Metallurgy of Silver, Gold and Mercury in the United States. Vol. II, p. S06, 1890. ■''Op. cit. p. 899. ■■''Clirist\-, S. B., Quicksilver condensation at New Almaden: Trans. Am. Inst. Min. Eng., Vol. XIV, p. 2:n, 1885. •■"■0;j. Ht. p. 264. QUICKSILVER RESOURCES. 247 REVOLVING FURNACES. A revolving' cement-kiln tyi)e ari-anged for quicksilver ore roasting has in the past been tried on at least two mines in California with mainly negative results. At the Socrates mine, Sonoma County, a White-Howell rotary roaster was installed in 1903,''^ but its use was dis- continued after a short period of operation. It was 50 feet in length, with an outside diameter of 5 feet, and lined internally with 6 inches of fire-brick, this cylinder being set on an incline of 6 inches in 50 feet. Photo No. 51. Rotary Ore-drier above Scott Furnace, at Socrates Mine, Sonoma County. The ends of the furnace were fitted into sockets or collars which in turn were fastened into the brickwork of the stack and fire-box. It was driven at 22 revolutions per hour, b}^ a 25 h. p. engine. This car- ried the ore through in 3f hours, and 1.6 cords of wood were consumed per 24 hours. The present operating company has recently cut down the length of this kiln, and re-installed it as a rotary ore-drier above the new 40-ton Scott furnace. (Photo No. 51). Another furnace of this type was built in 1911 at tlu' Aurora mine,^' San Benito Count}', but owing to mechanical difficulties was operated ^''Min. & Sci. Press, Vol. XC, Jan. 14, 1005, p. 22. Also: Forstner, Wm., Quicksilver resources of California; Cal. State Min. Bur., Bull. 27, p. 116, litO.i. *'.See the author's report in Minos & Mineral resourses of Monterey etc. counties; Cal. State Mln. Bur., 1917, pp. 57-58. See also Photo No. IS, ante. 248 CALIFORNIA STATE MINING BUREAU. at that time for only one day. Tn October, 1915, this furnaee was repaired and refitted and operated for a few weeks, until severe winter storms damaofed the roads over which the fuel-oil supply was brought in. Several flasks of quicksilver were produced. It is at present reported that work will be resumed there shortly. REVOLVING FURNACES AT NEW IDRIA. An experimental, revolving unit, (see Photo No. 52), was put in operation in March, 1918, at the New Idria Mine, Sau Benito County, which has certain new accessory features connected with it, by which it is hoped to make this type of furnace successful for the treatment of Photo No. 52. New Rotary Quicksilver Furnace at New Idria Mine. San Benito County, "after 58 days' continuous and successful operation." Photo by H. W. Gould. quicksilver ores. Mr. H. W. Gould, general superintendent, considers that the rotary has great possibilities. Thus far, it appears that their cost is one-fourth to one-half that of the Scott per ton-day-eapacity ; con- sumption of fuel one-third to one-half; labor one-fifth to one-half. It is more flexible than the Scott, the* ore passes through in 15 to 30 min- utes, with all of the mercury apparently expelled. There are no a))sorption losses in the furnace, as all the brick are hot. There is no personal element attached to the rotary, the feed and discharge being automatic, as against the irregularities possible with the hand labor on a Scott. Salivation of the workmen cannot result from the end joints of the furnace, because of the inward suction due to the stack draft. This first furnace at New Idria is 4' diam. x 50' long, arranged to drive at I-i to 4 r. ]). in., and a1 first treated 96 tons of ly ore daily. At present writing (Ai)ril, 191S) it is liaiidliiig 72 tons of 11" ore. i 1 PLATE XXXVI-A. p. CIS iKlii QUICKSILVER RESOURCES. 249 i ««!»», ik*tvS':-^^^i-'^'-^^ a St ir 01 is Phol qui thai is c sun is n utes absc pers autc a Sc of tl Tl (Iriv At I n QUICKSILVER RESOURCES. 249 (Sin iu;Ll:iliilNM!Mi »Hu'»»i>.«'>.o^')*'^^i'"-'«^W 250 CALIFORNIA STATE MINING BUREAU. GoukI thinks that ultimately 4" 1<» 1" will l)e found the economic size for the feed. The capacity of the furnace and the time of passage of the ore through it, depend on the speed of revolution and the thick- ness of the stream of ore, in addition to the size of the ore pieces. A thin stream of ore revolving rapidly can be completely burned and l)as.sed through the furnace in about 15 minutes; but a thicker stream must be run more slowl}^, or all the metal will not be driven out of the rock. A second furnace 5' x 56' is now being installed, and contracts have been let for 4 others of the same dimensions. It is too early yet to go further into the details of this installation, and its operation, but it is expected that with the financial backing of such a company and the the technical advice which it can command, that the device will be given an adequate and efficient trial.* MULTIPLE-HEARTH TYPE. The earliest furnace of this type was the McDougall, but the later, improved forms include the Herresehoff and Wedge. Some of the McDougall pattern are water-cooled. A Herresehoff, mechanically rabbled, circular furnace has been in operation over a year, at the Senator mine of the New Almaden com- pany, Santa Clara County. (See Photo No. 53.) It was installed early in 1916, by the then manager, W. H. Landers,^- who also, in con- nection with this installation, patented certain features of the condenser system. This furnace is 14 feet inside diameter and has 6 hearths, plus a drying floor on the top (see Photo No. 54). There are two fire-boxes on #5 hearth (next to bottom) level, set opposite to each other. On #2 hearth level, about one-third of the way around from the top exit-pipe, a third fire-box has been added in order to keep the temperature of the gases above 600° F. while going through the Cottrell dust precipitator which follows. The central column and the rabble arms are air-cooled, the resulting hot air being utilized for concentrate drying and other purposes. A Brown recording pyrometer is connected in at the furnace exit to enable regulation of the funic temperature. *Sinfe the above wa.s written, Mr. Coiilrl has very kindly loaned the writer the drawins.s of tliis new plant, and its provisional tlow-.shoot, with permis.sion to repro- duce. Fortiniately, it was not too late to include them hert-with. (See Plates XXXVI-A, and XXXVT-B.) The first kiln has now lieen in opin-ation for five months; the second will be fired up early in August ; the third has been set on its foundations, and the conci-ete is being pouic^l for the foundations of Nos. 4 and 5. The buiner (s<'e Plate XXXVI-A) sets in an air-tight door. Air for combustion is allowed to enter near the tailings discharge-door below, and must pass up over the hot tailings before reaching the combustion chamber, being thus pre-heated. At l>resent. steam is used for atomizing the fuel-oil. but compressed air will later be substituted. The burned rock from the furnace discharge drops into an inclined bin built of concrete.— July 26. 1918. *-See Eng. & Min. Jour., Vol. 102, Oct. 7, lOlfi, p. 63-}. QUICKSILVER RESOURCES. 251 This furnace is stated not to work economically on material coarser than 4 inch. Up to 58 tons have been treated in 24 honrs; but it seems to do its best work at between 40 and 50 tons. Feeding and discharg- ing are both automatic. The feed hopper is shown in Photo No. 54, while the honsing for the discharge may be seen in the lower left-hand corner of Photo No. 55. A steel ore-car is kept under the discharge chnte. and when filled is trammed ont by hand to the dump. Photo No. 53. Herreschoff Multiple-hearth Furnace at Senator Mine of New Almaden Company. Santa Clara County. By reason of the dust raised and thrown into the fume circulation as the ore is mechanically scraped from one hearth to the next, a bother- some a()rK("KS. 257 flo'ent for expelling this metal from its ores; but onee we have this preeious substance in its vapor form the fun hegins when we try to get it bade into a eolleetable condition. Retort condensers. With retorts, particularly the Johnson-^IcKay arrangement, fre- ([ueiitly the condenser is simply a 3^-inch pipe, 7 feet long (see Photo \o. ti2i. open to the air, as at the Patriquin mine, ]\Ionterey County; or the exit ends may deliver into a closed box (being often so arranged) ; or further elaborated upon and extended into other con- <]enser chambers and tlues with a circulatory system as at the Sulphur Bank mine. Lake County (see Photo No. 63; also Photo No. 41, of Photo No. 58. Condensers at New Mercy (Pacific) Quicksilver Mine, Fresno County. ^■Etna mine retort, ante). In the first case above-mentioned, Patriquin considers that complete condensation is obtained with the arrangement as it stands. He points to the fact that after the steam ceases to come off (about 45 to 60 minutes after charging), that the condenser pipe is cool up to within 18" to 24" from the retort wall. Also that, at one time for awhile, he had a cover over the ends of the condenser pipes as a safeguard against theft, during which period the pipes were always hot for their full length, and mercurial fumes could be detected coming 17—38540 258 CALIFORNIA teTATE MINING BUREAU. from the end of the box. With the present, open arrangement, except for the steam already noted, there are no visible fumes nor noticeable mercurial odors. It does not seem reasonable to expect that condensa- tion could be comph'te in .so short a distance. This point can Ije definitely determined only by samplinu' and analyzing- the escaping gases over a period of operation. However, the volume of gas to be ' Photo No. 59. Barrel Condensers, at New Idria Mine. San Benito County. cooled from a retort is very iimdi less in i)roportion to the tonnage of ore treated, as compai-ed with the large furnaces. Large Chamber Condensers. When we come to condensers for the larger, continuous-feed furnaces (the Scott will be taken as typical, as there are more of them in use, and the condensing problem is practically the same for all the large types, both coarse-ore and fine), th(^ situation become more complex. JTert! we have to deal with not simi)ly the vapors driven out from the QUICKSILVER RESOURCES 259 ore mass, but mixed with them are the products of fuel combustion. The questions of relative sizes, volumes and numbers of condensing chambers, materials for their construction, gas velocities, and temper- atures, become essential. So far, they have been almost entirely v.orked out on the 'guess and try-on' system.. Previous to the investi- gations now under way by the United States Bureau of Mines, the only attempt at scientific research in California in this direction was the Photo No. 60. Round, Wooden Condensers at New Idria Mine, San Benito County. work of Christy at the New Almaden mine in 1883-1884 from whom we quote the following:*'^ ..* * * rpj^ig quicksilver-fumes furnish often less than 1 per cent, by volume, of the pro(Juct.s of combustion with which they are mixed. Even the weight of the quicksilver is inconsiderable, compared with that of the gases which pass through the condensers. At New Almaden it is only about 2 per cent of the latter. * * * The minute condensed globules of liquefied quicksilver are likely to be carried off in the form of mist. The gases which escape from the condensing system, are neces- sarily saturated with quicksilver vapor at the temperature of escape. Then there is the ever-present mercurial soot, which requires separate treatment. The quicksilver itself is ready to escape from any crack or crevice of the condensers, either as a liquid or as vapor. * * * Finally, as soon as the condensers become cool enough to act effectively, they are attacked by the diUite sulphuric acid formed from the o.xidation of the sulphurous acid in the fumes. This agent slowly attacks and destroys almost every material out of which the condensers can be made. Tlie use of lead is of course out of the c[uestion, as that would be attacked by the quicksilver itself. "The system in use at New Almaden is based on the following well-known prin- ciples : "1. Cooling of the furnace-fumes by contact with large radiating surfaces exposed to air and water. *"Christy, S. B., Quicksilver condensation at New Almaden : Eng., Vol. XR', p. 207, 18S5. 'Pi-ans., .\m. Inst. Min. 260 CALIFORNIA SiTATE MINING BUREAU. Photo No. 61. Rectangular, Wooden Condenser and Flue, San Luis Obispo County. at Oceanic Mine, "2. Sedimentation of the condensed quiclisilver particles in enlarged chambers whefe the velocity of the gaseous mi.Kture is reduced. "3. Constant exposure to friction-surfaces, cross-currents and vortex-motions to remove the globules of metal by calling into play the force of adhesion." 41"* * * brick condensers cannot be regarded as very effective cooling agents. Tlie brick is among the worst conductors of heat, and it is found unsafe to build the walls thinner than nine inches. Besides, the mortar is slowly attacked by the acid fumes; gypsum and other sulphates being formed. These salts crystallize between the bricks, so that in some cases the walls of the older condensers have been so bent out of shape by this cause as to be unsafe. The bricks themselves are often attacked, and some of the outside walls of the old condensers are wliitened by thick crusts of sulphates." 4.-,<.« ♦ ♦ J), j^j^j. long Vieen noticed at New Almaden that the rapidity of condensa- tion depends not only upon the cooling-surface and sedimentation volume, but also upon the area of friction — or adhesion — surface to which the fumes are exposed. * * * The utility of eddies and cross-currents in the fimies themselves has also been well recognized." His conchisioiis'""' rcljitivi^ to qnipk-silvcr ooiulonsntidn are snniniod up. as follows: "1. The volume of prmiianrnt fjnscs j)a/fi". \ QUICKSILVER RESOURCES. 269 "The small fume loss just referred to does not necessarily mean that there are very few extremely fine particles of quicksilver formed in the condensers, but is to be explained rather on the ground that owing to the large amount of water vapor present these minute quicksilver particles become rapidly weighted with water which condenses on them as nuclei. This type of suspended matter is in general easier to recover than dry dust particles which do not readily adhere to one another or surfaces with which they come in contact. The suggestion then which may be taken from the Great Falls practice is that something resembling a wire-baffle fume-chamber, which for quicksilver practice might take the form of a redwood box, with narrow strips of redwood suspended within, might effectively replace a considerably larger volume of open settling chambers. Probably the more valuable conclusions to be drawn from these Great Falls experiments are rather of a negative character in indicating the lines along which efforts for the improve- ment of recovery systems are likely to be unproductive. "Draft regulation. "Under usual furnace practice a slight positive pressure exists in the furnace exit pipes, but beyond this point a negative pressure or in-draft is found throughout the condenser system. Some operators are inclined to favor a slight positive pressure in at least the first part of the condenser system, but this seems scarcely advisable as a small iuleakage of cold air will cause very little, if any, increase in the usually negligible ciuicksilver loss from a stack, whereas, the escape of gas from the condenser system inevitably involves a certain loss of metal. When the gas passages and connecting flues are of liberal dimensions a condenser system can be operated with surprisingly little draft. At one plant a maximum of 0.1 centimeter of water was observed and at another the maximum was 1 centimeter of water. Occasional observa- tions of the draft at above points along the condenser system will be found useful as a control over its operation and will furnish a ready means of detecting any partial stoppage of the gas passages. Owing to the small pressures involved, an inclined U-tube or Ellison gauge giving a multiplication of ten or twenty times is necessary." "Fume loss from stack. "Among tbe possible sources of loss of mercury from the condenser system, the escape of the metal from the stack in the form of vapor and fume has received considerable attention from some operators in the last year or two. First, as to the possi1)ility of vapor loss ; taking 40° C. as a representative .stack temperature it will be ob-served by refer- ence to the chart (Plate XXXVI) ^ that 0.00007 kilograms of mercury are required to saturate one cubic meter of air measured at 0° when ' See p. 2 ns, nut p. 270 CAl.ll'ORMA STATE MINING BUREAU. heated under constant pressure to 40° C. Assuming, in line with previons discussion, that TiOO cubic meters of gas measured at 0° C. and atmosplierie pressure leave the furnace per metric ton charge, only 0.035 kilograms mercury are required to saturate this volume of gas. This corresponds to 0.0035% of the weight of the ore which would be only 1% of the mercury content of about the lowest grade ore charged to furnaces at present. With a stack temperature of 60° C. the vapor loss would be four times as great, corresponding under the above assumption as to volume of gas leaving the furnace per ton of charge to 7.5 kilograms or 16.5 pounds of mercury per day for a 50-ton furnace. This loss will, of course, increase as the volume of gas leav- ing the furnace increases and also probably to a somewhat lesser extent in proportion to the air leaking into the condenser system. "A series of actual determinations of vapor and fume loss was car- ried out at two plants. These determinations involved an accurate sampling of the stack gases and a measurement of the volume of gas leaving the stack. In one case the stack carried the gases from a single Scott furnace treating about 70 tons of material averaging lf( mer- cury and in another case the gas stream sampled was derived from the treatment of about 100 tons of lower grade ore. The stack temper- ature ranged from 30" to 50° C. The maximum loss observed amounted to about 3.5 kilograms (7.7 pounds) in 24 hours. It is thus evident that so long as the stack temperatures and gas volumes are kept within reasonable limits, the quicksilver loss from the stack will be unimportant. "Water losses. "Another possible source of loss of quicksilver from the condenser system is through the condenser water. This may carry finely divided mercury in suspension as well as mercury salts in solution and as sul- phuric acid is usually present in varying amounts it is not unreason- able to supi)ose that a certain amount of mercury may have been dis- solved by the acid. As the recovery of tlic mercury in suspension is merely a matter of settling or filtration, pai-ticular attention was given to a determination of tlie chemically combined mercury in solution. The highest mercury content found in any sample of clear condenser water under normal running conditions amounted to 0.04 grams per liter. As the flow of water from the condenser system of a 50-ton furnace is not likely to exceed 1.000 to 2,000 liters (6 to 12 barrels) per day, the loss of mercury in solution is so small as to l)e negligible. Water leaving the condenser system at the time of the periodic clean- ups ma\' carry somewhat greater (|nan1i1y of mei-enry salts in solution. but it does not seem likely that the h)ss of inereui-y involved is iiiipoi't- ant." QUICKSILVER RESOURCES. 271 SOOT. The quicksilver as thrown down in the condensers is always mixed with more or less fine-dust oi'e particles in the first condenser, and in the others with a black 'soot'. This was mentioned in the introductory .section'"*' under properties of mercury. According to Christy,^* analyses show this soot to be "composed mainly of unburned carbon and hydrocarbons of tarry empyreumatlc nature. The ingredients come mainly from the imperfect combustion of the fuel, but also in some part from the tarry matter in the ore itself. The former cause might be removed by careful tiring ; but the latter * * * could hardly be avoided. "The soot contains, mechanically entangled, large quantities of metallic quicksilver, most of which can be removed by mechanical treatment. * * * "The New Almaden soot contains more or less scrapings from the walls of the condensers, and in the colder condensers, where the moisture has had time to condense and the sulphurous acid to oxidize, the soot is impregnated with dilute sulphuric acid. The hot condensers next the furances furnish mainly dry quicksilver and soot mixed with ore-dust. Further on they furnish quicksilver, acid waters, and damp soot, and the last condensers furnish dribbling streams of inky acid waters, holding various sulphates in solution, colored by the soot and carrying small amounts of finely divided quicksilver. The soot of these chambers is, of course, a black mud. Finally, the side-hill flues, deprived of the larger part of condensable moisture and quicksilver, furnish nearly dry soot which rarely shows to the eye any free quicksilver." The soot was mixed with wood ashes, and placed on an inclined cement floor; then worked with a wooden hoe as long as any metal would run out ; after which the residue was re-charged to the furnace with the ore feed. In 1882, the soot produced 4% of the mercury vield of the two coarse-ore furnaces ; and the soot of the two fine-ore furnaces, 5.6% of their yield. Soot is generally worked by a similar hoeing at most plants, with the exception that lime is more often used than wood ashes, and the residue is generally retorted. The relative amount of soot obtained, and the percentage of mercury carried by it vary considerably^ at different plants. At the Oceanic mine, San Luis Obispo County, with pine wood fuel, some 40% of the total mercury recovery is through the soot. After working out as much as possible by mechanical means, the bal- ance is retorted. From the recent investigations of the U. S. Bureau of Klines Experi- ment Station, Dr. Duschak contributes the following on soot formation : ' ' The formation of mercurial soot in the condenser system i.s a source of considerable annoyance and expense to the operator. With the thought that an understanding of the con.stitution of soot might give a clue as to the conditions which favor its formation and eventually sug- gest ways of reducing the amount formed, a number of samples were •'••See p. 200. ante. '^Christy, S. B., Quicksilver condensation at New Almaden : Trans. Am. Inst. Min. Eng., Vol. XIV, pp. 227. 22S, 1885. 272 CALIFORNIA STATE -MIXING BUREAU. collected from the condenser systems at two plants and a few represen- tiitive analyses are pivon in tho nccomjinnyinfr tabulation: "Analyses of Mercurial Soot. Per cent Per cent Per cent Hg— free Hg as HgS... Hg as HgSOi R:;0.> (mostly CaO MgO S03 S (in HgS) .... Carbon Acid insol. Moisture at 110' and Hg: Fe=03).. SO. C. Totals. 47.00 0.62 3.34 1.12 1.51 O.lfi 7.41 0.10 not det. 23.52 14.10 64-58 3.53 none 5.53 0.07 0.15 2.05 0..57 not det. 12.25 10.74 78.83 0.28 0.68 0.58 0.74 0.07 2.41 0.04 not det. 11.06 7.18 Per cent Per cent 98.88 99.47 101.87 58.72 0.54 0.06 0.76" 0.16 0.14 1 3.63 0.09 not det 15.98 10.52 39 9 .50 83 .06 2.26 3 9 23 11 .96 .45 .90 2 9 90.60 94.C6 "These analyses are neither complete nor highly exact since the alkali metals have not been determined and where carbon is reported it probably occurred partly in the form of heavy hydrocarbons of which only the carbon content was determined. Both the amount of free mer- cury and moisture present are more or less accidental, depending on the method of collecting and handling the sample before analysis and, owing to the presence of a certain amount of sulphuric acid, drying at 110 ' C does not expel all the moisture. "These analyses coincide with the prevailing idea that the soot con- sists of minute particles of mercury mixed with small amounts of mer- cury compounds, with finely divided mineral matter from the ore and often carbonaceous material. Generally speaking, the amount of chemically combined mercury in the soot is small. ]\Iercurous and mercuric sulfate are usually present, but the greatest amount of mer- cury found in combination as sulfate in any sample was 3.3% of the total mercury present, which latter amounted to 41%. This sample was taken from the portion of the condenser system nearest to the furnace and its high content in sulfates of mercury (mcrcurous and mercuric sulfate were not diflt'erentiated) is consistent with observation made by quicksilver operators that sulfate is more apt to form in the warmer part of the condenser system, particularly if any sort of pocket exists whcic the circulation of gases is not good. This is what one would expect from a ciiemical standpoint. Sulphur trioxide and watei vapor with possibly sonic undissociated sulphuric acid vapor occur in the furnace gases and as these cool, droplets of sulphuric acid will form at about the same time that the condensation of mercury vapor begins. The first sulphuric acid to condense will be moderately con- centrated and we thus have at some point in the condenser system drop- QUICKSILVKR RESOURCES. 273 lets eousistiug of mercury or sulphuric acid and iti most cases probably both at a temperature high enough to cause fairly rapid interaction. "The amount of mercuric sulfide present in soot is usually small, but in a few eases a considerable amount was noted. This sulfide may be due to cinnabar dust from the furnace charge, to sulfide volatilized as such in the furnace in the absence of sufficient oxygen for combination with the sulphur, or to the formation of mercuric sulfide through chem- ical action of sulphur compounds in the gas stream upon free mercury. Some observation in the field, as well as laboratory experiments, indi- cate that this last source of sulfide in soot is by no means negligible. "Soot then is to be regarded as consisting essentially of minute parti- cles of mercury which are prevented from coalescing by other sub- stances present. It is evident that the amount of soot will be less, the smaller the amount of mineral dust and carbon soot accompanying the mercury laden gases from the furnace. A dust chamber, which may be built either as part of the furnace (as in the Scott furnace) or as a separate structure, will collect a certain amount of the coarser dust, but unfortunately it is the smallest dust particles, which can not be stopped in this way. that are most efifective in the generation of soot. When the amount -of this dust is excessive, electrical precipitation by the Cot- trell Process offers an effective means of cleaning the gases. The 'treater' required for a furnace of ordinary size occupies comparatively little space and, as electrical precipitation of suspended matter can be accomplished at elevated temperature, it is possible to remove ore dust and other suspended matter from the furnace gases without condensing any of the mercury vapor. "Several considerations indicated that the influence of the factors promoting soot formation, namely, the mechanically carried dust parti- cles and the chemical formation of mercuric sulfide could be minimized by very rapid condensation. This idea was at least partially confirmed by some small-scale experiments in which gas was drawn from the furnace down-take through a water-cooled tube. , The mercury con- densed in this way coalesced readily and the amount appearing in the form of soot was in all eases less than 5% of the total mercury- recov- ered. These experiments, together with the points mentione"d above in speaiiiug of condenser operations, point to the desirability of devising a practical method for the rapid cooling of quicksilver furnace gases." 18—38540 274 CALIFORNIA STATK .MINIXG BUREAU. Because of its susceptibility to closer reoiilation, it would seem that better combustion could hv attained tb rough the use of oil as fuel than with wood. Landers^'-* considers that "Fuel oil, such a.s is u.sed In California needs a great amount of air for complete combustion and has the di.sadvantage of making a very greasy soot that is carried over into the conden-sers and greatly retards the collection of the mercury. To prevent this, it is necessary to have large fire boxes in which the combustion of the oil can take place, allowing only the hot gases to escape into the furnace." Photo No. 66. Cleaning i:p one of the new. wooden condensers at New Idria. The bright globules of metallic quicksilver and the "gray mud' may be seen on the discharge lip. In contrast to tins, is the result at the Great Eastern mine, Sonoma Cotinty, wlicrr wood lias i-eeently hccii r('i>laeed b\- oil as fuel. It is stated that whereas before the eliange considerable soot had to be bandied and \v;is i-cfortcfl. now a I'rw ])nck»'ts of drv dust are ()])tained ""Landers, W. II., Tlie Smelting of mercurv ores: Eng. & Min. Jour., Vol. 102, p. 632, 1916. QUICKSILVER RESOURCES. 275 in the tirst condenser, only, ami it is not necessary to run the retort. This, too, with an ore carrying a noticeable amount of natural bitumen. Thouiih the composition of soot will vary according to the time and place of sampling, analysis of a ty{)ical sample of soot at the New Idria mine (January, 1917) showed: ^lercury 63%; silicates 21%; small amounts of iron oxides, lime, soluble sulphates, and occasionally a lit- tle carbon. There is also a little mercuric snlphide carried over in the dust. Most of the soot they are now getting there is from the con- den.<5ers (^f the coarse-ore furnaces, which have not yet had the improve- ^ 4 ■ • ' . Photo No. 67. Soot Mill at New Idria Mine. San Benito County. Ball-mill in rear. Senn pan-amalgamator in foreground. ments added that are in service at #1 fine-ore furnace— namely : the vertical, circular, wooden chambers, and the introduction of cooled air. In cleaning np the new wooden conden.sers of #1 furnace, the materials washed down and scraped out are globules of quicksilver mixed with a gray nnid (see Photo No. 66) which is practically all quicksilver. By working it mixed with some lime, with hoes on an inclined plate, the niftal particles coalesce and run down a launder to the bottling room. When visited by the writer in Octol)er. 1917, the soot at New Idria was being treated in a special plant installed within recent months, and giving very satisfactory results. As stated in the preceding paragraph, the material came mainly from the older brick and stone conden.sers, 27G CALIFORNIA STATE MINING BUREAU. Avith a little nnul from the new, wooden chambers. It was mixed, by hand shoveling-, with 3% by weight of lime (CaO), in a wooden tank, to neutralize acidity and fed through a screened opening (1") into a Hendy laboratory ball-mill. This mill is unlined, but with cascades cast in the shell, being 4' long and 30" diameter. It has a helical-screw feed and center discharge. Chrome-steel balls of 1^" diameter were used, and were obtained by sorting out the small sizes from the large ball-mill in the concentrator plant. The ball-mill polished the dissem- inated quicksilver and allowed it to coalesce. This took place, im- mediately, to such an extent in the ball-mill, that the accumulated metal there had to be drawn otf at least once each shift. The pulp next passed to a Senn pan-motion amalgamator (see Photo No. 67), the sur- face of which is covered with a silver-plated copper plate, and the * con- centrate' discharge was through the center to a mercury well. The tail- ings from the Senn passed to concrete settling tanks, whence the water was drawn off, the sludge dried and sent to #1 fine-ore furnace. The final Senn tailings assayed up to 60 lb. of mercury per ton (3%), from heads carrying as high as 1200 lb. per ton (60/^). This plant was driven by a 10 h. p. Type Y, semi-Diesel, Fairbanks-Morse, oil engine. Condenser conditions have recently so far improved that at the present writing (^lareh, 1918), use of this soot mill has been discontinued. I QUICKSILVER RESOURCES. 277 QUICKSILVER ASSAYS. There are two ma in .systems of assaying ores for quicksilver, one involving distillation, and the other solution. The methods in the first named are more direct and reliable, quicker and require less manipu- lation. Among the earlier of these, the most reliable one was that of Eschka,^ wliich is essentially that of heating a weighed sample of ore mixed with iron tilings in a crucible with a gold foil on top kept cool by a weighted cover filled with water. Though following the same pro- cedure, Whitton- while a senior student in the College of Mining, Uni- versity of California, developed an improved form of apparatus for this assay, now known as the 'Whitton apparatus,' which has since been adopted commercially. This method and its manipulation is taken up more in detail in subsequent paragraphs. Another similar apparatus is known as the James. The 'glass tube method' is another, involving distillation. This is summarized by ThornhilP as follows : "To determine the total mercury (both metallic and sulphide), 0.5 gm. of the material is well mixed with cast-iron filings, free from grease, and placed in a hard glass tube, sealed at one end, with a contraction at about 2 in. from the sealed end. The mercury is distilled off, by heating the bulb containing the charge, and con- densed, in the tube just beyond the contraction. After the distillation is complete, the contracted portion of the tube is heated, the bulb portion pulled off, and the end of the tube sealed. The tube containing the condensed mercury is allowed to cool, filled one-half full of 0.1% KCN solution, and 10 to 15 100-mg. gold beads added. Each bead will amalgamate with about 1-mg of mercury. The tube is shaken until all the mercury is amalgamated ; the beads are transferred to a small porcelain cup, washed with water, dried with alcohol and weighed. After retorting off the mercury, they are again weighed. From 10 to 12 deteiminations can be made in one hour by this method and it is accurate enough for control of operations." Of those involving solution, the best is probably that known as the Krieckhaus Volumetric Method, described in detail by Low.* It is essentially as follows: Dissolve 2 gm. of ore in 2 cc. HNO3+IO cc. HCl, by allowing to stand cold an hour or more. Dilute, filter, and add stannous chloride solution to filtrate. After standing 2 hours the pre- cipitated mercury will have settled to bottom. Filter and wash free of chloride ; dissolve Hg in cone. HNO;, ; add ferric nitrate as indicator, and titrate cold with standard potassium thiocyanate solution. The latest, improved quicksilver assay, adopted within the past fcAV months by the assayers at the New Idria and Sulphur Bank mines is a combination of the last two above-mentioned methods. It is es.sentially : Distillation in a closed tube ; then dissolve mercury in cone. HNO3 and titrate with thiocyanate. This method seems to have proven to be the best yet, and bids fair to become generally adopted for commercial 'Zeit. f. anal. Chem., Vol. 11, p. 344 ; also. Low, Technical Methods of Ore Analysis, p. 156, 1905: Furman's Manual of Practical Assaying, IS'ri, p. 133. ^W'hitton, W. W., The determination of mercury in ores: Gal. Jour, of Tech., Vol. 4, No. 1. pp. 35-39, 1904. ^Thornhill, E. B., Recovery of mercury from amalgamation tailing: Bull. Am. Inst Min. Eng.. No. 104, 1915, p. 1653; also, Min. & Sci. Press, vol. Ill, p. 212, Aug. 7, 1915. ♦Low, A. H., Technical Methods of Ore Analysis, pp. 156-15S, 1905. 278 CAIJI'OHMA STATK MINING BIHEAU. \v()i'l<. Di". Duschak has recently investigated it (|nite thoronphly, iniprnviug the finesse of the process in some of its details, and has also made some comparisons with other methods. His observations are sum- marized for this present report^ as follows: "A considerable number of both wet and dry methods of mercury assaying have been tested. Of these the Esclika method (Wliitton apparatus) was found to be convenient and reasonably accuiate for oidinaiy low-grade ore and furnace tailings. Witli high-s'i-ade material, sucli as concenti-ates, the results were not satisfactory and the method fails entirely when pyi'ite, free sulphur or organic matter are present in any (|uantity. The method now used at the Berkeley Experiment Station is a com- liination of older procedure with various new features developed in our laboratory. \Vith slight modifications it may l)e applied to high and low-grade products and to material containing free sulplun-, pyrites and organic matter. "Eschka method. "The apparatus used in the ti-ials of this method was that due to Wliitton. Silver foil was used to collect the mercury. This method was not found accurate for ores containing more than a few per cent of sulphur or a trace of organic matter. With low-grade material containing 1% or less mercury there appeared to be a tendency toward high results to the extent of a few per cent of the mercury present. High results are frequently accompanied by a discoloration of the silver foil. Tliis occurred even with iron filings which liad been purified witli great care and in some cases was traced to excessive lieating of the crucible. An ordinary Bunsen burnei- flame about 4 cm. higli with the tip of the inner blue cone just touching the bottom of the crucible was found to supply the right amount of heat. The usual heating period was fifteen minutes. "With material carrying over 15% mercury the results were apt to be low and erratic, due presumably to escape of mercury vapor between the crucible and foil. Occasionally a few globules of mercury were found adhering to the upper part of the crucible. '"Bureau of Mines method. "This consists, in brief, in heating the ore mixed with a powdered reagent in a glass tube closed at one end, dissolving the distilled mercui->- in nitric acid and titrating with a standard thiocyanate solution. "Apparatus. "The glass tubes are heated in an iron block 13x9x8 cm., resting on a 13x9 face, and enclosed on all sides except the bottom with V' asbestos board. This may well be further covered by J" transite board and the coverings fixed on the block by machine screws. Twelve 11-mm. holes are bored through the block and its coverings, passing thiough the 9x8 faces. These holes are in three tiers of four holes each. The block is placed on a slieet of asbestos board which rests on a tripod support. A 2 J" hole is previously cut in the asbestos board so that the fiame of a Meker Ijurner may impinge directly against the iron. A six-incli Meker burner gives ade- quate heat but in the absence of gas a Dangler gasoline lamp would unquestionably be efl^cient. Asbestos aprons reaching from the bottom of the furnace to the table top shield the front and rear faces of the furnace from hot ascending air currents. "The glass tubes may be of common soda glass or of Pyrex or similar heat-resisting glass. If of common glass a new tube is used for each determination, as the glass softens and distorts at the temperatures used. The tubes should not exceed 10 mm. in external diameter and the walls should be fairly thin, less than 1 mm. through. The length should be from 22 to 25 cm. In the case of soft glass the closed end should be rounded off (like a test tube) and a large drop of glass at the tip should be avoided. On the other hand, Pyrex glass tul)es which may be used repeatedly should be drawn out to conical ends and a tiny button of glass shoidd be left at the tip of the cone. As will be described later, this tip is bioken off in i-emoving the mercury from the tube. Tlie small hole is easily sealed again by drawing out the glass in the llame (with an auxiliary bit of Pyrex tubing) and reforming the small button. The tube is thus made ready for another assay. "Witli soft glass tubes loose plugs of asbestos fiber may be used to hold the charges in place. If the plug is at all tiglitly packed it may hinder the How of mercury vapor. Owing to the manipulation invoUed in the use of hard glass tubes a different sort of plug, which may be made as follows, is necessary. A piece of l)iass or copper gauze of ai)out .">0-mesh is cut into rectangles about 12 mm. wide by 18 to 25 mm. long. Four e(|uidistant incisions about 5 mm. deep are made in one of tlie longer edges. Tlie gauze is then l)ent around a piece of small tuliing into a cj'linder and tlie flaps are bent inwaid, closing the cylindiM- at the bottom. A piece of niehrome wire, about 2SB. it S. gauge and about .'! cm. long is woven into four holes, punched l)y a needle in tlie gauze, in such a way as to leave two small loops projecting from the walls of the cylinder. The'se loops ai<' bent along tlie cylinder walls toward the open end of tlie cylindei-. Niehrome ictains considerable elasticity at the teniiierature of the furnace and these plugs, inserted with the closed ends against tlie charge, keep their positions in spite of the expansions and contractions attending the temperature changes. Several dozen plugs .should b(> made ready for use. Before insertin.g, the nichi-ome wire should always l)e lient out a little to make sure of a snug fit. "By permission of the Director, U. S. Bur. of Mines. QriCKSIlAKK KKSOURCES. 279 "A soft steel rod 3 or -1 mm. in diametei- ami about 40 cm. lonj; .should be Ijcnt into a rins at one end and a short sharp, lateral sian- shoidd be formed at the otlier end. This rod serves to push the plugs in and to di-aw tliem out when the a.ssay is finished. "Special reagents. "A few drops of ratliei- strong potassium permanganate solution are needed for each assay. 'J'his is most conveniently delivered from a dropping bottle. "A ferric sulphate indicator for the titration is prepared b.v heating 10 g. of salt with 100 cc. of water. This must be absoluteli,- free from all halogen compounds. The 2 cc. needed for each assay may be measured with a pipette tixed in the stopper of the indicator bottle. As the indicator imparts some color to the solution the amount used should be consistent. "Titration is made with either a tenth or hundredth normal potassium thiocyanate solution, both of which should he kept in stock for use according to the quantity of mercury to be determined. The solution is quite stable and keeps its titer unchanged for at least several months. "The solutions are standardized against pure mercury. For the hundredth-normal solution about 10 to .^0 mg. mercury should be taken. This small pellet can be obtained b>- using a pipette like the ordinary medicine dropper, but providing it with a capillary tip 6 to S cm. long. A thread of mercury of about the right length (determined by a few trials) is drawn up, the pipette withdrawn from the mercury and pressure further relaxed until the mercury pops up into the wide part of the stem. The pipette is weighed, the mercury expelled into a flask or beaker, and the pipette re-weighed. It is advisable always to make two such weighings for each drop of mercury because when the mercury pops up into the stem a minute pellet is sometimes detatched from the rest of the mercury and remains in the pipette without detection. The mercury is dissolved in about 10 cc. concentrated nitric acid, diluted to about oO cc. and treated as in regular titrations as described below. "In addition to the above, granular CaO (about 60-80 mesh), powdered and finely granular CuO and 37f H„0.. are required. When the material to be assayed contains much sulphur or organic matter, KCIO:; is needed. A supply of crushed granite or other hard rock through 10 and on 20-mesh is needed in charging the tubes. "Procedure for samples low In sulphur and organic matter. "One gram of ore is weiglied in and about one gram of finely granular lime or fine, clean iron filings is added. The material is mixed thoi'oughly on a watcli glass with a spatula and poured into tlie tube througli a small short-stemmed funnel, brushing off with a camel's-liair brush. If Pyrex tubes are used a pinch of tlie crushed granite is placed in each tube iiefore charging. If an appreciable amount of organic material or a rather high percentage of sulphur is present, from 0.5 to 1 gram of powdered copper oxide is added before mixing and a layer of about 1 to 2 cm. of granular oxide is placed on top of the charge in the tube. To each tube add a 5-mm. layer of crushed rock and seal in witli one of the brass gauze plugs. "The tubes should be tapped gently on the table to form an air channel along the side of the charge, and then placed in the furnace. The front of the cliarge should be at least 3 cm. from the face of the furnace. Tlie furnace has. or course, been previously brought up to temperature (450°-5.50° C), about IJ hours' heating over the Meker burner being necessar.v. After heating fifteen minutes the tubes are withdrawn and each is placed open end down in a test tube (|"x.5") containing 10 cc. concentrated nitric acid. The test tubes are placed in a sheet-metal rack having a thin layer of sand at the bottom and placed on the hot plate. When the distillation tubes have cooled sufficiently for handling, the tips are broken. A piece of thin-walled rubber tubing is slipped over the broken tip and connection is thereby made with a small wash bottle containing strong alkali solution. Suction is applied to the wash bottle by mouth until the acid is drawn from the test tube above the mercury distillate. A fine frosting or mirror of mercury is instantl>' dissolved, while larger drops of mercury become loosened and drop into the test tube. After all the tubes have been thus treated the rack is replaced on the hot plate for complete solution of the mercury which reciuires 5 to 10 minutes. The contents of each test tube is then poured into a properly marked 100 cc. beaker, 10-1.5 cc. hot water added and drawn up by suction into the distilling tube. This washing with a second similar one, which is sufficient to remove all traces of mercury, is added to the original solution. "To each beaker is added a small amount of permanganate solution, and the beaker rotated to secure thorough mixing. Successive portions of permanganate are added until the color becomes permanent. If this treatment is omitted so))te of the mercury remains in the mercnrous state and loiv results are obtained on titrating. The excess of permanganate is destroyed by one or two drops of hydrogen peroxide. (Ferrous sulphate solution is equally effective.) "Two cubic centimeters of the ferric sulphate indicator are added and as soon as it has cooled to room temperature the solution is ready for titration. If the amount of mercury was greater than about 50 milligrams, titrate with the tenth-normal KSCX ; if less, use the hundredth-normal solution. "With the more dilute solution the end point is, of course, not so sharp as with the tenth-normal solution, but the end can nevertheless usually be fixed within a tenth of a cubic centimetei-. "Since a single eriuixahnt of mercuric mercury is 100 grams (100.3 to be exact) one cubic centimeter of hundredth normal KSCN is eqinvalent to one milligram of mercury. "In all treatment subsequent to the distillation of menui-y great care must be taken to avoid the introduction of any lialides. A ver.v small amount of chloride ion lowers the mercury titer to an appreciable extent. All liquid reagents and the water used must therefore be free from chlmidcs. The presence of chlorides in the ore 280 CALIFORNIA STATK .MIXIXG BUREAU. charge presents no difficulty, foi- the theoretical amount of mercury has been found when pure calomel lias been takfii as tlie cliarge. "The process as above described presumes the use of Pyrex tuV>es. If tomnion glass is used the technic is some\vhat modified. After the fifteen-minute heating in the furnace the assay tube is drawn forward about an inch and lotated on its axis while a glass rod around which is wrapped a layer of absorbet|t cotton saturated with cold water is held against the tube close to the furnace. The glass is shattered in a zone about the tube and a slight pressure releases the forward portion, which is slid, sliattered end first, into the test tube of nitric acid. When the nitric acid has dis- solved all the mercury (placing on the hot plate tlie while) the tube is lifted from the nitric acid and rinsed with a jet of water from the wash bottle. The titration is completed in the usual way, not omitting tlie treatment with i)ermanganate. "Modification for samples high in sulphur and organic matter. "If the material to l)e assayed contains a large percentage of sulphur or of organic material or if it consists of a precipitate on a filter paper, special procedure is necessary, otiierwise the distilled mercury may be contaminated with sulphide or organic materials which will interfere with the titration. Some mercury, moreover, is often retained in the charge unless complete combustion is effected. To assure complete combustion the charge is made up as follows : One to two grams of potassium chlorate are mixed with about the same volume of crushed rock and poured into the bottom of the distillation tube which should be about 30 cm. long. This charge is covered with about 1 centimeter of the crushed rock and the material for assay then added. If the sample admits, a rather large proportion of powdered CuO should be well mixed with it before pouring into the tube. A filter paper, on the other hand, after drying should be coiled into a cylinder and pushed down the tube. A bulky precipitate should be removed from the filter, mixed with CuO and charged into tlie tube, on top of the coiled filter. The substance for assay having been charged, a mixture of granular CaO and CuO in the proportion of one part of the former by weight to two of the latter is poured into the tube to a depth of five or more centimeters. This reagent should contain no particles below 60 or 80-mesh in size as they may reduce the porosity of this column to such an extent that gases accumulating behind may blow the column forward, spoiling tlie assay. The column is capped by a thin cover of crushed rock followed by the usual brass-gauze plug. The total length of charge must not exceed 12 cm. "The tube is tapped gently' to make an air passage above the material for assay, but a ciiannel above the CuO-CaO mixture should be avoided as far as possible. The tube is then inserted in the furnace, pushing it rapidly through the iron block until the material for assay is clear at the back. The CuO and CaO mixture remains in the furnace and is thus preheated. After three or four minutes the tube is gradually drawn forward bringing the charge into the furnace. From now to the end of the heating the tube requires the constant attention of the assayer. It is advisable to insert, in the open end of the distilling tul^e tlirough a small one-hole stopper a glass tube of about 2 mm. internal diameter, which is bent down at right angles and passes through a two-hole stopper into a small test tube containing 3-5 cc. concentrated nitric acid. This device acts as a bubbler to indicate the rate of flow of gases and also as a washer to absorb at least the ma.ior part of any mercury vapor that may pass this far. After titrating at the close of the experiment the contents of tliis tube may be added to the titrating breaker to determine if any additional KSCN solution is required. Ordinarily no appreciable amount of mercury is found here. The passage of the distilling tube into the furnace is so regulated that the bubbler shows a suc- cession of passing bubbles whicli never coalesce into a continuous stream. At first the volatile organic matter and free sulphur are expelled and are completely oxidized upon entering tlie column of CuO. The acid gases produced are largely absorbed by the CaO. Wlien the potassium clilorate charge begins to enter tlie hot zone oxygen is evolved and especial care is needed here not to make tlie evolution too rapid. The nonvolatile carbon is consumed in the oxygen stream and the mercury completely expelled from the charge. If, however, the forward part of the column is lacking in porosity the oxygen pressure may become higli enougli to cause tlie precipitation of mercuric oxide and part of tlie mercury may thus fail to distill out. .After tlie mercury is distilled the bubbler is disconnected, the tube removed from the fuinace and the assay completed in tlie usual way. It is recommended tliat the assayer on fii'St using this inethod acquire confidence in his technic In- wt'igliing out a drop of pure mercury as for a standardization of thiocanate, dissol\ing it in a small amount of nitric acid, diluting, precipitating with hydrogen sulphide, filtering and assaying filter paper and percipitate." THE WHITTON METHOD. When lib' aiillior he- referring to tlie aceompanyins cut, [Plate XXXIX], which will serve as a woi-king drawing for its construction. Briefly it consists of a steel retort, with a cover of sheet silver, and above this a flat-bottomed cooling dish of brass, these three essential pieces being clamped tightl.v t(5gether as shown. Thus arranged the distillation is performed in a closed retort, which prevents the escape of mercury vapor, and renders careful regulation of the heat unneceesary. Another important advantage lies in the use of the steel retort. It sliouhl be recognized that mercury vapors will condense upon any surface below the boiling point of mercury, 357.82° C, whether that surface be ore with whicli the.v will amalgamate or not.^ The steel retort is a good conductor of heat, and tlius all portions of it are readily brought above this temperature, while the foil is kept below this temperature by its contact with the bottom of the cooling dish ; thus the vapor must condense upon the foil, and not upon any other portions of the exposed inner surface of the retort. "The retort or crucible Is turned from mild steel to the sizes shown, and the top surface should be faced off true and smooth. Several forms of retort were tried, but this design gives the most satisfactory results. It has a small capacity and exposes a comparatively large surface to the action of the vapor. "The cooling dish is of cast brass ; this metal is a good conductor of heat and does not readily corrode. The cross-bar may be soldered in place ; the bottom should be faced off true and smooth. Several forms were tried ; in one the flat bottom of the dish was cut out. leaving a ring-shaped "dish" in which the water was in direct con- tact with the foil. But trial has shown that it is not necessary that the water be in direct contact with the foil, and in the form used dessication of the foil is avoided ; thus shortening tlie assay materially. "The clamp should be of such size as to include the ring of the retort stand used to support the appaiatus ; it can be made by any blacksmith. "The sheet-iron shield should be at least 1/16 of an inch thick, preferably 3/32 ; if much thinner it will buckle when the clamp is screwed down. "As a recipient silver foil is used in pieces about 13 inches square, and of such thickness tliat a piece of this size weighs about 1.4 grams. It can be obtained from almost an.v dealer in assajer's supplies at a cost of two dollars per ounce. Foil 2" wide and free from holes and cracks should be specified. Thus one square costs about eight cents, and as a foil will last for from five to ten assays, the cost per as.say is inconsiderable. Upon the surface exposed in the retort as much as 0.15 grams of mercury may be deposited, but it is preferable to use such quantities of ore that not over 0.05 grams will be deposited, when the amalgam formed adheres firmly to the foil. "As a desulphurizer, or flux, iron filings are used. The preparation of the filings is important. They should be put tluough a 5 0-mesh sieve, washed very thoroughly with alcoliol or carlion disulphide to remove grease, and heated for an hour or more in the muffle or upon a hot plate. It is not advisable to have them too fine, and all that will go through an 80-mesh sieve should be discarded if the best results aie desired. A blank test with the filings should not increase the weight of a new foil nor discolor it. "The assay is conducted as follows: Take from 0.15 to 2 grams of the ore, accord- ing to richness, place in the retoi-t, and mi.x very thoroughly with about 6 grams of tlie prejiared filings, adding 3 grams more as a co\er. Weigh a square of foil, and assemlile the apparatus, screwing the clamp down firmly. Fill the cooling dish witli water, and heat for 17 minutes. If a Vnuisen burner is used regulate the heat as follows: liave the liottom of the retort about li inches from the top of the burnei-. The gas flame should be turned down quite low, and the blue cone should just strike the bottom of the retort while the flame runs up the sides of the retort for about J an incli. Tlie tendency of a l)eginner is to have too high a lieat. The water in tlie cooling dish shoidd come to a boil in six or seven minutes, and should be allowed to boil thi-oughout the assay, being replaced onl.v once or twice as it boils away. This keeps the foil above the boiling point of water, while below that of mercury : tiius no water remains upon the foil at the conclusion of the assay, and dessication of the foil is unnece.ssary ; it may be weighed almost as soon as it is removed from the retort as it cools very rapidly. No evidence of overheating has appeared in many assays; and the clo.se attention of the operattir is not necessary during the heating. .At the expiration of the 17 minutes heatin.g, the assay is allowed to cool until it can b" handled ; this takes about 5 minutes. It is then dismounted and the foil conveyed, under cover to avoid dust, to the balance and weighed. The increase in weight is due to mercui-.v, and the percentage is readily calculated. "The time required for an as.say is about 30 minutes. By using two sets of apparatus, and four foils, weighing up the fiist pair of foils while the second pair is in use. they may be made in 15 minutes. With three .sets of apparatus the time may be rediK'eii to 12 minutes for continuous work. The deposit upon the foil shoidd "Whitton, W. W., The determination of niercurv in ores: Cal. Jour, of Tech. Vol. 4, No. 1, pp. 30-39, Sept. lltOl. 'Chism, R. F., A new as.say foi- niricnry: Trans. .\iu. Inst. Min. Eng., vol. 28, 1898 "This is true only for the \apor of pure mer(ur.\- at one atmosphere pressure. The pressure of other gases lowers the conilensing temperature. J QUICKSIF.VKK KKSOl'RCES. 283 be white in color ; if tlie heat is too Ions and higli the deposit will assume a dark color: this dark deposit is volatile, and is apparently due to oxidation of the mercury. Assays in which this color has appeared are not very reliable ; they may vary either way from the correct result, but generally higli. "In the case of ores containing much water, on removing the foil it is occasionally found to ha\e tilings upon the deposit, and also is stained a dark color in spots. This is due to a drop of water condensing upon the foil and falling back on to the hot charge in retort, where it boils violently and throws up the charge on to the foil. This may be avoided by heating up the charge slowly, or if very persistent, by the use of a shield above the charge. Probably asbestos wool would be good to use for this purpose. « * * "Duplicates on ores carrying under 0.50'7f mercury should agree within 0.01% ; on ores under 1% mercury they should agree within 0.02% at the most. "The method has been frequently checked against the work of other assayers, giving results in close agreement." Photo No. 68. Whitton Quicksilver-assay Apparatus, showing component parts. In this present work, the author used three sets of the apparatus,— two as put on the market by the Braun-Kneeht-Heiman Co., San Fran- cisco, and the third set being the original one made for AVhitton in the machine shop of the Department of Mining & Metallurgy, University of California. Photo No. 68 shows the component parts of the apparatus (there being 2 crucibles or retorts, and 2 cooling dishes shown, so as to give top and side views), and Photo No. 69. the same assembled. The thumb screw should be of brass, and it would be better if the clamp were also of the same metal, because the steam rising from the water in the cooling dish in a very short time rusts the screw threads so that they do not work smoothly. The cooling dishes in the sets made by the Braun company have two cro.ss bars for the clamp-screw bearing cast in tiie form of a -|- iiistead of a single bar as in the original Whitton set. The writer found this to be an advantage, as it was noticed that due to expansion on heating, the single bar had a tendency to warp the dish, thus preventing the bottom from remaining a plane surface. A 284 CALIFORNIA STATE MINING BIKEAU. plane surface, obviously, is necessary for a close contact with the foil and retort. If iron filings, alone, are used as a Mux or de-sulphurizer. they should be absolutely clean, and free from grease. Cast-iron was found not to be as .suitable as cold-roHed. mild steel, or wroutiht-iron. Well-burned, Photo No. 69. Whitton Quicksilver-assay Apparatus, assembled. high-grade lime can also ho used; hut a mixture of iron filings and lime in equal parts seems to give cleaner and more uniform results than either alone. The lime apparently takes earc of any irregularities in the iron. Sharwood" also considers a mixtiire of the two preferable to either alone. •Sharwood, W. J., Tlie dcteitiiinaliun ul' intTLiuy in ivuiiide solution and pii'cipi- tate: Min. & Sci. Press, Vol. Ill, ]<. 663, October 30. IIUO. QUICKSir.VER RESOURCES. 285 To t^xpodite the work when assaying' a nunilier of samples, the writer kept in use 6 pieces of silver foil and 2 of gold. The gold foils have been used 26 and 28 times, respectively, and the silver from 22 to 31 times each, and they are all still serviceable. This is considerably more than Whitton's "from five to ten assays."^- Before using, each foil was freshly ignited to redness over a bunsen burner, conveyed in a des- sieator and weighed. After amalgamation, the foil was likewise con- veyed under cover to the weighing room, following which it was ignited to redness to expel the mercury, then polished with very fine fioured- emery paper to insure a fresh bright metallic surface. Apparently this ignition did not expel all of the mercury, as the foils gained in weight, especially after running a high-grade sample ; though after such, notable increases there was always a slight falling back, when lower grade sam- ples were run, but in no case, did any foil used by the writer return to as low as its original weight. The following tj^pical cases will show the variations in weight of the particular pieces of foil before each assay : Xo. 2 foil (gold) weight in grams : 6.3359: 6.3382 : 6.3379: 6.3377; 6.3375; 6.3376; 6..3376: 6.3373; 6.3377; 6..3377 ; 6.-3377; 6.3376; 6.3378; 6.3376; 6.3376; 6.3376; 6..33S0 ; 6.3380: 6.3377: 6.3377: 6..33S1 ; 6.3379; 6.3381; 6.3381; 6.3384: 6.3393; 6.3387; 6.3390. No. 4 foil (.silver) weight in grams: 3.052i>; 3.0525; 3.0524; 3.0527; 3.0541; 3.0&46: 3.0550; 3.0.550; 3.0559; 3.0.555; 3.0563: 3.0558; 3.0561; 3.0555; 3.0560: 3.0567; 3.0567; 3.0572; 3.0567; 3.0562; 3.0.559; 3.0564; 3.0554; 3.0552: 3.0556; 3.0555: 3.0555; 3.0554; 3.0559. Concordant results were obtained on the same samples with both gold and silver foils ; but in some cases the silver gave slightly higher results, due possibly to sulphidizing, a.s in all such the surface was somewhat discolored. Gold is more satisfactory to use in all cases, but especially for close work; though silver dees for the ordinary run of samples. Proof-metal was used in both cases, and cut into 2-inch scpiares. The writer has assayed up to 14 samples in -l hours, with 3 sets of appa- ratus and 8 foils. With additional sets of the apparatus, a larger num- ber of assays can be made. The samples were ground to pass 80 mesh. The investigations of Duschak, quoted on a preceding page, indicate that the closed-tube and thiocyanate-titration method is superior to the Whitton especially for materials carrying above, say 10% mercury. For materials assaying less than 17< mercury, the Whitton has the advantage of capacity for a larger sample. Up to 3 gm. can be taken. ■nVhitton, W. W., The determination of mercury in ores: Cnl. Jour. Tech., Vol. IV, No. 1, p. :5S, 1904. 286 CALIFORNIA STATE MIXING BUREAU, Chapter 2. CONCENTRATION OF QUICKSILVER ORES. In the author's investigations, the samples treated were stage- crushed to pass a given screen, the larger ones being coned several times l)efore quartering down, and the smaller ones cut down with a Jones 10-division, hand-sampling grizzly. The crushers used (see Photo No. 70) were a Sturtevant roll-jaw crusher, 6" x 6", and Sturtevant labora- Photo No. 70. Crushing and Sampling Floor in Mill of Department of Mining, University of California, Berkeley. tory rolls 8" diameter x 5" face. These were used in connection M-ith a shaking screen (seen at right edge of photograph). The samples were all crushed and screened dry. hccaiisc wet ci-ushing could not be done witli the rolls as installed. Samples treated. Jl — Fines collected Feb. 21. IHKI. fi-oiii silc of old fine-ore bin of Scott furnace, a1 Oat Hill iiiiiic Xapa County, — 50 lb. Tliis was fine material, all under .\ inch size, which had sifted through from the ore bin which liiid o!ie time been nbove it. It was mosth" of frial)le sand- QUICKSILVER RESOURCES. 287 stone, with the einiiabar distinctly crystaline. Assayed 3.88% mei'eury. Screened throuuh #10 mesh before sampling. 52— Oat Hill mine, Napa County, Feb. 20, 1916—300 lb. of loAv-yrade material, mostly sandstone, from #2 B-Fanny waste dump, with which was mixed 85 lb. of small, hard lumps carrying quartz, cinnabar and {)yrite. Assayed 1.99% mercury. Screened through #4 mesh before sampling. These two Oat Hill samples were collected by the author through the courtesy of Mr. J. E. jMiller, one of the lessees. #3— ^tna mine, Napa County. Feb. 25, 1916—400 lb. of tailings from Colorado bumping tables.^ These tailings were impounded during operation of the plant by a lessee in 1915. The ore had been ground by a Griffin mill to pass jtlS-mesh screen. It was in part, hard siliceous material from underground workings, and in part, soft ochreous material from surface cuts and dumps. j\Iuch of the cinnabar was fine, soft, and 'painty' even before grinding. This sliuied and paint cinna- bar largely remained in suspension and floated off from the tables. Assayed 0.385% mercury. The writer has no knowledge of what the bumping-table heads ran, as the operator did no sampling nor assaying. #•1— ^tna mine, Napa County, Feb. 25, 1916—200 lb. from old waste dump on Phoenix ( ?) claim. This material had considerable clay mixed in with it. and the cinnabar was ver.v fine. Screened through |:4 mesh before sampling. Assayed 0.157% mercury. Samples jf3 and jf4 were sent by l\Ir. A. A. Cibson, then superintendent for the operating company. it5 — Patriquin (formerly Parkfield) mine, Montere}' County, Feb- ruary, 1916 — 200 lb. of hard, siliceous, low-grade, surface material. The rock is a silicified serpentine, and the gangue minerals chalcedony and calcite. The cinnabar is crystalline, occurring in veinlets and along the fracture faces, with a little associated pyrite. All screened through #10 mesh before sampling. Assayed 0.45% mercury. it6 — Patriquin (formerly Parkfield) mine, Monterey County. Feb- ruary, 1916 — 100 lb. from ore being retorted, and stated to be yielding an average of 4% quicksilver. As described by the author- in a recent report: "The country rocks are serpentine and Franciscan metamorphic sandstone. The ore body is a zone containing parallel stringers of cinnabar with the intervening rock and its fractures more or less impregnated witli the mineral. It is in part stockwork. The vein filling is (|uartz, opaline silica, and chalcedony, and much of the serpentine is silicified. The cinnabar occur.s as distinct crystals, not as 'paint'." All screened through #10 mesh before sampling. 'See author's report on .T^tna mine: Cal. State Min. Bur., Rept. XIV. pp. 2'<:^-285, 1916; also in advance chapter on Napa County, pp. 111-113, 191.'i. =Cal. State Min. Bur., Report on mine.'; and mineral icsources of Monterey et al. counties, p. 19, 1917. 288. CALIFORNIA STATK MIX INT, BUREAU. Assayed 1.42';.r luereury. Samples #5 and #6 were sent by Mr. Lewis Patriquin. part owner. #7— Big Injun mine, Lake County, Feb. 21, 1916—20 lb. delivered to tlie writer by IMr. T. A. Peterson, lessee. The ore was mainly soft serpentine carrying native mercurN- and distinctly crystalline cinna- bar. Because of having only brass screens available for the shaker at the time this sample was crushed, it was put through the rolls set at :1 inch and not screened. It was then rolled on a cloth and a sample for assay cut out with a spatula. Later, before concentrating, it was again put through the rolls, set up close so as to crush to approximately #20 mesh; but not screened, as the native quicksilver would have amal- gamated with the brass. Assayed 1.39% mercury. Still later a por- tion of the sample was ground on the bucking-board to pass a #40 mesh iron-wire screen, and an amalgamation test made with gold beads in a 0.1% KCN solution, which showed 0.51% native mercury present, or 36% of the total assay value. #8 — St. John's mine. Solano County March, 1916 — 630 lb. from mine-run ore being sent to Scott furnace. Sent by ]Mr. Clifford G Dennis, manager of St. Johns ]\Iines Co. The ore occurs at the con- tacts of a series of faults and meta-andesite dikes. This meta-andesite macro-scopically resem.bles some Franciscan metamorphic sandstones. The cinnabar, mainly crystalline, is in part disseminated in this rock, and in such occurrences resembles the Oat Ilill ore, but is harder and somewhat silicified. The cinnabar is also, in part, along the fractures. There is some shale present, a little associated pyrite, and occasional spots of a thick, brown petroleum. All screened through #6 mesh before sampling. Assaying 0.49% mercury. #9— Cambria mine, San Luis Obispo County, March, 1916 — 238 11). sent l)y ]\[r. Ellard W. Carson, manager. This is a hard, cherty, siliceous ore, carrying cinnabar and a little native quicksilver. The cinnabar was all crystalline, but some of it very fine, and occurred mostly in Iho fractures. All screened through #10 mesh iron-wire, before sampling. Assayed 0.31% mercury. An amalgamation assay with gold beads in a 0.1% KCN solution, on ij:40-mesh product showed 0.005^{ native quicksilver present, or 1.6% of the total a.ssay value. 210 — Goldbanks mine, near Winnemucca, Humboldt County. Nevada, Api-il. 1910—200 lb. of mine-run ore sent by Mr. AV. G. Adam- son, owner. This ore is a breccia (apparently quartzite or a rhyolitic tuff, but so altri'od that its original character is not readily deter- mined), which has been re-cementi'd by silica, mainly chalcedonic. Tlit^ cinnabar occurs almost entirely in the cementing silica and in the frac- tures, llic cinnal)ar and silica apparently having been ju-ecipitated from solution simultaneouslv. The ore is extremelv hard and fine-grained, QUICKSILVER RESOURCES. 289 the cinnabar being almost, if not quite, crypto-crystalline. Examina- tion of a thin-section under th(^ microscope by transmitted light, did not reveal any distinguishable crystal outlines at 250 diameters magnification. With a reflecting microscope, revolving the section on the stage, an occasional glint was noted of what was probably a crystal face reflection, at 175 diameters magnification but at none lower. (See colored reproduction on Plate IV, ante.) Having seen a specimen of this ore at the Panama-Pacific Interna- tional Exposition in 1915, the writer solicited a sample for concentra- tion tests, recognizing in it an extreme case. Such it has proven to be, as is shown elsewhere herein. The cinnabar in this ore has not the brilliant vermilion color that one ordinarily finds in this mineral, because there is a yellow, iron oxide (probably limonite) intimately associated with it. A qualitative chemical test of a rather clean flo- tation-concentrate sample gave a strong reaction for ferric iron. The entire sample was crushed to pass a #16-mesh screen before the por- tion for assay was cut out. After crushing, the whole mass had a decided pink color, due to the cinnabar being so finely divided and so thoroughly scattered through the ore. Assayed 1.72% mercury. Tests as to the applicability of both flotation, and of solution in an alkaline sulphide. Avere made on this ore ; but none were made with table con- centration, as it is obvious from the nature of the cinnabar occurrence that such would prove futile. jtll — Esperanza mine, Sonoma County, September, 1916 — 150 lb. taken in the mine b}' the writer, through the courtesy of Mr. Carlos G. White, part owner. The cinnabar, which is coarsely crystalline, occurs, in part, in serpentine and is also found disseminated in sandstone. There is also a black shale. There is some native quicksilver. The vein minerals are quartz, dolomite ('/), and calcite; and some chlorite is associated with the serpentine. All crushed to pass JflO-mesh iron- wire screen before sampling. Assayed 1.67% mercury, #12— Bella Union mine, Napa County, Mar. 15, 1917—410 lb. from old waste dump. The material is ochreous, and is made up largely of serpentine and a metamorphosed rock, probably a sediment, somewhat silicified." The cinnabar where visible is crystalline and is accom- panied by a little pyrite. Chlorite, an end product of the weathering of the serpentine is noticeably present. Crushed to V' before quarter- ing down for assay sample. Later, entire sample screened through #10 mesh for table concentration. Assayed 0.14% mercury. #13— Bella Union mine. Napa County, Mar. 15, 1917—325 lb. of ore from underground workings, not ochreous. Largely of serpentine — and a metamorphosed rock which seems to be in process of serpentin- ^See Becker, U. S. G. S. Mon. XIII, p. 377. 1!)— 38540 2f)0 C'AIJIOKNIA STA'I'i; MINIXC HI KKAT. ization. ('hlorilc iiccoinpaiiics. 'llir ciiiuahai' is coarsely .•ry.stalliiie and massive, oeciirrin.ii' in part as veinlets. Quartz also occur- in vein- lets, and there is a litlle ii'on sidpliide present, ("rushed to V' before (luarteriuy down for assay saini)le. Later, entii-e sample screened thronjiii #l. 03 a a I—" a; OJ ;-i a C« «t-i CO o UJ VI <0 •t-l > Jj _1 < OJ Pi *2 -e O >) 6fl ^ X Ul OJ oc bfi -t-l r/? () CU en -tJ o !« -fj 33 o s ;3 TJ ,^2 O ca ?H 4-> a bo '^ ^H • r^ > crt o 05 ^ a> o ;~i =f-l o CIJ , u --•O'S S ^ -+ as "I cj >. M + •<2 » a ;2 G 'I' 2oa 0/ "S a . "55 . aa ■"Set; •a c a a§S ►J H (- CJ QVJ lU ag a a H B 00 lO CO(N cqioo oo CO CO CO O lO ?o t^ to oo ^ ocq 050 ooo i-O r^ CO 0( OOr-l OlO 00(5 x3 CO 1-1 ^ -f 03 03 o 4 OJ o 4 + o I to CO o 4 tOT-< oo oo uioo 00 (M po (Ml^ CO I— c co-^ »CCO oq o N -:>< -* o 'a" c5 p«3 o-i CO o>p -^ CO lO ^H o p lO *c o< O! 00 00 oo CO lO 05C^ ■^ rr t-~- oo 1-H CO o o r^to 050CO «> O 00 8g coO; o f-i . — ' 03 <_i O PhXO u g O a o "S ■ a QUICKSILVER RESOURCES. 293 Summary of screen analyses. By an examination of the table of screen analyses, herewith, the fol- lowing will be noted: Oat Hill fines (Sample ftl)— 43% of the total value is in —80; while over 26% is in — 20 + 48 ; balance being about equally distributed between + 20 and — 48 + 80. JEtna bumper tailings (Sample #3) — practically 80% of total value is about equally divided between — 20 -(- 48 and — 80, with the latter in the lead. Balance about equally divided between -{- 20 and — 48 + 80. ^tna— flotation tailings from test on bumper tails ( — 100) (Sample PK5A) —50% of total value is in —200 and a little over 33% in + 150. Parktield, low grade (Sample #5) — 45% of total value is in — 80, and 27% in —20 + 48; with 67%, of balance in +20. St. John's (Sample #8) — a little over 50% of total value is in — 20, and nearly 25% in — 80 ; with 90% of balance in — 20 + 48. Cambria (Sample #9) — over 50% of total value is in — 40, and about 33% in + 20. Goldbanks (Sample #10) ore crushed to — -16 mesh — nearly 50% of total value is in — 20 + 48, and about 30% in — 80. A little over 10%. in + 20, and a little under 10% in — 48 + 80. Goldbanks flotation test tailings on — 100-mesh product (Sample #10A11A) showing 73% extraction— 75% of total value is in + 150. and a little over 20% in — 200. Under the hand lens, cin- nabar seen on coarser particles in all three sizes. Bella Union tailings from Deister slime concentrator test (Sample if 13 C) on — 16-mesh product, showing 30% extraction — 44% of total value is in — 20 + 65 ; 31% in — 150 ; and 20% in + 20. 294 CALIFORNIA ST ATK MINING RrRKAU. CONCENTRATION ON TABLES WITH WATER. Tilt* autlioi-'s experimental work in the iiietaliurgieal laboratory and mill of the Department of Mining' and ^Metallurgy, University of Cali- foi-nia. covered two periods of continuous operation 8 hours daily — ^[arch -2 to April 15, 1916, and February 8 to May 12, 1917. In addi- tion to tliis some weeks were spent each year, in the course of field work for the State Mining Bureau, ])articularly September and October, 1917, in gathering data on and obsei'viug the operation of plants at the various ciuicksilver mines throughout tlie State. Rolls were used to crush the samples for concentration because they have been found to produce a iiiiiiiiiium of slimed material. Cinnabar being very friable, 'grinding' should be avoided if possible, otherwise the sulphide will be slimed and it will then float away or remain in sus- pension until after it passes out the tail-race. Crushing and screening were done on the dry ore. Three tables were used: a regulation, stand- ard-size Wilfley; a small, laboratory model Wilfley-type machine, built in the shop of the department under the direction of Prof. Christy shortly l)efore his death; a half-size Deister slime concentrator installed in April. 1917, — a gift to the College of ^Mining from the Joshua Ilcndy Iron Woi-ks and the Deister Concentrator Company. The standard Wilfley operated at 250 r. p. m.. and the laboratory model at 225 i-. }>. m. These speeds are about right, but the 'bump' at the end of the stroke is not decided enough — it should l)e sharper. A small test-run was also made on a new model Gates tal)le at the Bay City Iron Works. Oakland. Samples #1. 6. 7. 11, and 18 were treated on the small, laboratory model ; and tf9. 12, and 13 on the Deister. The concentrate discharge of the WilHey table was so aiTanged at first, that when running samples #2, 3, an' would have a value of hut :^'-].10 per ton. Sample lfl3 — Bella Union mine. This sample was ei-ushed to i»ass 4{16-mesh screen before coneentratinf?. Tlie tailings assayed 0.35% mercury, auainst 0.50% in the heads, oi' an indicated extraction of but 30%i. The concentrates assayed 4.48% mercury. A separate mid- dlingvs product was not made, this material being divided between the concentrates and tailings. It was noted during the run on this ore that tlat pieces of the coarser cinnabar would ride along on top of the gangue. particularly in the middlings area, and finally be washed over into the tailings launder. The wi-iter was informed by Mr. S. E. "Woodworth of the firm of Hamilton, Heauehamp and AVoodworth who had made a series of milling tests on ore from this mine, that they had noted the same behavior in their experiments; and that the ore required ci'ushing to 40-50 mesh before this tendency could be overcome, — that is. before the particles were crushed fine enough to lack that flatness which caused them to ride on top of the gangue. The coarser, cry- stalline cinnabar in the Bella Union ore has a platy structure. Refer- eiu-e to the screen analyses {ante) on the tailings from this test shows 44% of the total value in the —20 + 65 material. 31% in —150. and 20% in -r 20. Sample %\A — La -Joya mine. Tliis sample was crushed to pass JliJ mesh screen. Xo tal)le test run was nuide on this ore, as the sample was small aiul it was evident after a panning test that table concen- tration, alone, would make a low recovery. In panning, the slimed cinnabar floated off in air bubbles on the surface of the water. There was an abundant concentrate of the coarser, crystalline cinnabar, but much cinnabar was washed overboard due to being held in uncrushed l)al•ticlt^s of the gangue. A combination treatment of flotation (for the fines) and tabling (for the coarse) wtiuld pi-oliably yield a good i-ecov- ci'v from this ore. Summary re table concentration tests. The Otic point which impressed itself most strongly upon th(> writer during these experiments was the necessit.v for classification of feed when concentrating. The table (or belt machine, either) is not made which can successfully concenti-ate materials of moi-e than a narrow range in size at a single operation. Another point is, that apparently 'paint' and .slimed cinnabar ar(^ not recoverable l\v tables, as such prod- ucts remain in suspension in the i)uli>. even float off as a film on the surface of the wafci-. It must l)c borne in mind that these experi- ments were eari-ied out under .somewhat unfavoi'ablc circumstances, at least so far as irregularities of pulp consistence were concerned, and the irreLfularifics of |)ulp flow resulting' fi'om the intcrmiltenee of hand qUICKSILVKR RESOURCES. 299 feeding'. Tn spite of these irreoularities, excellent results were obtained ■vitli the favorable Oat Hill samples, and fair results with cer- tain others which could b(> i)nproved upon with more favora])le manip- ulation. Native quicksilver is readily recoverable by tables, though large globules have a tendency to roll around and jump the riffles instead of advancing along them. In view of the excellent results obtained at New Idria with the vSeun pan-motion amalgamator oper- ating on soot, this machine would doubtless work well on ores carrying native quicksilver. Possibly a settler witli revolving arms, similar to the settlers used in the old Washoe-pan process of silver amalgamation, would work well on such ores. 3U0 CALIFORNIA STAPH iMIXINC BUREAr CONCENTRATION BY FLOTATION WITH OILS. Al'l'ARATUS. In the first few flotation tests made by the author in this series, in March, 1916, a Hyde ('Slide') machine was used, but clamped and the pulp allowed to overflow (see Photo No. 71). In the balance of the series, in February-April, 1917. which covered a far greater range of ores and oils, and a greater nuinl)er of tests, the Case (Hoover type) laboratory flotation machine was employed. (See Photo No. 72.) These and various other laboratory, testing units are well described by Ralston and Allen^ in the most complete paper as yet published on this phase of flotation practice, and to which the reader is referred for more detail than is here given. Photo No. 71. Hyde ('Slide') Laboratory Flotation Machine, as used in the metailurgical laboratory of the Department of Mining, University of California. As above stated, the Slide or Hyde laboratory flotation machine as used by the author was clamped so that the upper and lower parts were not separable. A tin pan was soldered around the top (see Photo No. 71), to act as a sloping discharge launder for the overflowing froth and concentrate. Sub-aeration was introduced through the tube shown at the left, drawn in by suction of the propeller blades in the bottom of the agitation compartment. Power was furnished l)y a 60-cycle, ^ h. p., 220-volt, 4-amp. induction motor at 1800 r. p. m.. driving the agitator shaft at 1500 r. p. m. A charge of 300 grams of ore with 2400 cc. of tap water (temperature 20°-25° C.) was used. The water was first put in. the air tube closed, motor started and 10 drops of oil 'Ralston, O. C and AUen, G. L., Testing ores for flotation process: Min. and Scientific Press, Vol. 112. pp. 8-13, 1916. QUICKSILVER RESOURCES. 301 added. After 2 minutes agitation, for the oil and water to emulsify, the ore was added in a small steady stream, and allowed to agitate for 2 minutes before opening the air-supply tube. Agitation was then continued for 20 to 25 minutes, during whieh the froth arising was occasionally raked off with a spatula on a level with the top of the agitation compartment. At the close of the test, the tailings were Photo No. 72. Case Laboratory Flotation Machine. drawn off through an opening in the bottom of the agitation compart- ment. Both tailings and concentrates samples were dried and weighed. At the end of all tests, both with the Hyde and the Case apparatus, the inside of the machine was thoroughly wa.shed out to avoid contam- ination of the oils used. The Case (Hoover type) Flotation Machine (see Photo No. 72) is a laboratory unit built by the Denver Fire Clay Company, Denver, 302 CALU-UKNIA STAli; .MIXING BLHKAT. Colo. It consists of a sinLilc alninimiiii casting comprising the agita- tion cell and a spitzkasten for the collection of* the froth. Within the agitation cell are hung' the shaft and imiieller, the four l)lad»'S of which ai-e set at !)(>". The steel shaft is coated with lead and the impeller hlades are made of an aHoy to resist the corrosive action of acids. A piece of heavy rubber tubing connects the spitzkasten and agitation cell at the bottom. About half \\a\- down from the toj) of the spitz- kasten. an opening (^ inch high x 1 inch wide) in the wall also eon- Photo No. 73. Froth on a Flotation Test with the Case Machine. nects with the agitation compartment. This opening is controlled by a vertical, slotted plate, with m baffle at its lower end. When the machine is in opei'ation the i)iilp and f'rotli work from the agitation compartment, through this opening 1o llie spit/.Uasfen from which tlie gangue on settling to the bottom is drawn throiigli the rubber tube by the suction of the im|)eller blailes back into tlie agitation compartment. This gives a continuous circulation of the i>nl|) through the two cells as long as the test lasts. The impeller shaft is driven by a d. K. QUICKSILVKH HKSUL'KCES. 303 indiu-tidii iiioloi'. type DSS, W33, 220 volts, i li. p. (iO cycles, operating at ISOO r. p. 111. The larger two of the pulleys give the impeller speeds of 1800 and 1300 r. p. in., respectively. A lip on the edge of the spitzkasten provides for the overtlow of the froth (see Photo No. I'-U. which may also be skimmed oft' from time to time witli the small metal hoe pi'ovided. In the earlier tests by the writer with tlie Case machine, the impeller was started, and 2000 ce. of tap water put in — temperature 22° ± C, I lien 10 drops of oil added. After running two minutes to allow the oil and water to emulsify, 500 grams of ore ( — 100 mesh) were added gradually. After 10-15 minutes, as the volume of pulp and froth required to give an overflow became reduced, more oil and water were added, gradually. The capacity of the machine is 3000 ec. The test was continued for a total of 20-30 minutes, or as long as any concen- trate seemed to make its appearance on the top of the froth. There was no sub-aeration in the Case machine, as with the Hyde. Following the first few tests, the order of adding oil and ore was reversed. Also, a ]Mohr pipette of 1 cc. total capacity, graduated to 0.01 cc, was employed for measuring the quantity of oil used. In the tal)ulations, 'drops' of oil have been converted to cubic centimeters, in the figures representing the earlier experiments. The impeller was started, with 2000 ce. of water ; then 500 grams of ore added gradually and allowed to agitate 2-3 minutes for mixing, with the side hole closed. Then, the oil and any other reagents were added, following which the side hole was opened, and the test proceeded as before. Time of treatment was counted from the introduction of the oil. In most of the tests with the Case apparatus, the impeller was driven at 1800 r. p. m. ; but a few were run at 1300 r. p. in. OILS USED. Through the courtesy of Mr. Niel Nielsen, Commissioner, and Mr. A. C. Gilleland, chief clerk of the Trade Commission to America for the Government of New South Wales, stationed in San Francisco, the writer received samples of three Australian eucalyptus oils, which were utilized in several of the tests detailed herein. These have been desig- nated for convenience of reference, #1. #2, and #3, Eucalyptus, respectively. The descriptions were furnished liy the donors, and the specific gravity determinations were made by the writer. #1 Eucalyptus— Rectified oil of the 'White Top' or 'Gully Ash,' Eucahjpius smith ii, R. T. B., from New South Wales and Victoria. One of the richest in eucalyptol, and containing no phellandi-ene. Specific gravity 0.912. #2 Eucalytus — Crude oil of the 'Broad-leaved Peppermint', EucaJyptus dives Schau. from New South Wales and Victoria. It consists largely of the terpene phellandrene, eucalyptol, being present 304 CALIFORNIA STATP: MINING BUREAU. only in minute quantity. Thi.s oil is largely used for mineral sepa- ration. Specific gravity 0.908. #3 Eucalyptus — 'Citronella,' crude oil of the 'Citron-scented Gum,' Eucaljjptus citriodora Ilook, from Queensland. It consists almost entirely of tlie aldehyde citronellal, and contains no eucalyptol. Spe- cific gravity 0.874. Through the courtesy of Mr. Frank E. Mariner, president of the Pensacola Tar and Turpentine Company, Gull Point, Florida, samples of a number of their pine oils were received and utilized in various tests. The following summary of the constants and characteristics of these oils is condensed from the company's catalogues. "The con- stants given are averages. Most of the oils are crudes, and constants are apt to vary slightl.y, though not sufficiently to interfere with prac- tical operations." ^75_Crude Wood Turpentine. Sp. gr. 0.887. Dis. Pts. 65°-217° C. Ref. index 1. 456. Viscosity, 0.9. Non-poly- merizable matter 10-12%. PO— Redistilled Pine Tar Oil. Sp. gr. 0.982. Dis. Pts. 160°- 368° C. Ref. ind. 1.5636. Vise. 5.8. Non-polymerizable matter (see note). It is free from pitchy matter. p50_Special Crude Pine Wood Oil. Sp. gr. 1.019. Dis. Pts. 70°-345° C. Ref. ind. 1.525. Vise. 2.9 Non-polymeriz- able matter 4%. Has a low pitch content, and "is not a gangue lifter ordinarily, but combines excellent frothing and collecting qualities." #400— Crude Wood Creosote Oil. Sp. gr. 1.025. Dis. Pts. 190°- 360° C. Ref. ind. 1.4977. Vise. 2.9. Non-polymerizable matter (see note). A mixture of pine oil and wood creo- sote oil recovered from the caustic soda still bottoms of the refinery. It is stated to be an excellent all-round flo- tation agent, but only a limited quantity of it is recovered. #750— Heavy Pine Tar Oil. Sp. gr. 1.063. Dis. Pts. 165°-350° C. Ref. ind. 1.557. Vise. 41%. Non-polymerizable matter (see note). It is "the total crude dropped out of the steam rougher still after the light products have been taken off, and therefore contains some pitchy matter. It is a good collector find is extensively used." #1580— CVmibination Pine Oil. Sp. gr. 0.980. Dis. Pts. 85°-352° C. Ref. ind. 1.5361. Vise. 2.3. Non-polymerizable matter (see note). This is a mixture of one part of #80 (crude pine oil) with two parts of #15 (thin rosin oil). "Appar- ently a useful oil in special work * * * Joes not seem to be of general adapta])ility." I I I^UICKSILVER RF:S()rRCES. 305 Samples of Nos. 1"), 80, and '200 wci-c also received l)iil not utili/ed. for lack of time. Note: ''Tlie heavier oils which contain more or less redistilled i-osin oils or heavy tar oils cannot be successfully tested for Non-polymeriz- able matter by the sulphuric acid test." From samples in the storeroom of the metallurgical laboratory, the following- oils were utilized in certain tests: Calol Flotation Oil "B", Standard Oil Company. Richmond. Cal. Sp. gv. 0.878-0.892. A compound of mainly mineral oil, with some pine products. A California crude petroleum, of asphaltic base, from "Well #16, Sec. 15" (probably Midway field) ; 15° ± Baume, or 1.115 sp. gr. In those tests where this oil was employed, it was added before the pine oil ; but in no case did it give any appreciable froth, alone. Through the courtesy of Mr. S. S. Skelton, of the Georgia Pine Tur- pentine Company, the author has received samples of several of their notation oils since the laboratory experimental work was closed; and regrets that lack of time has prevented utilizing these oils in some fur- ther tests. EXPERIMENTAL DATA. The tabulation herewith gives in condensed form the results of the tests made by the writer. They are all shown, — good, bad, and indif- ferent, that comparison may be had of the variations resulting from changes of oils with the same ore, changes of ores with the same oil, changes of dilution of pulp, changes of agitation speed, and other pos- sible combinations. The 'indicated' percentage of extraction {i. e., tails: heads) is shown rather than the actual, partly because it involved a simpler calculation, and partly because the results on the whole are merely relative, anyway. A sufficient comparison can be had one with another so long as they are all calculated upon a common basis. The necessary elements (weights of tailings and concentrates) for figuring actual 'recovery' are present if it be necessary to determine it in any particular ease. The concentrates of only a few of the most satisfac- tory tests were assayed. It was anticipated that difficulty would be encountered in assaying flotation products, particularly concentrates, with the Whitton apparatus. It did not prove so, in most instances. In the majority of cases, there seemed not to be enough oil present to interfere, neither in concentrates nor tailings. This was particularly true where pine products were utilized. Where a mineral oil had been used in the combination, it was necessary to wash the concentrate sam- ple with ether before assaying, otherwise the results were low, and not concordant. 20— .'5S540 306 CAI>IFOH\IA STATE ^TIXIXO RIREAT'. DATA OF 1 9 op is 300 300 300 300 500 'r. C v: Oil used Otlier reagent added T ■r. u 3 Kind Amount At start o — Nuinbt'i- I'f sample CO Total added later, cc. o"3 si 3 * CI4 80 80 80 SO 100 #350 P. 1500 P. 2 Euc. Calol B. #75 P. 0.47 0.38 0.35 0.34 0.34 20 20 20 20 5ii 1 8:1 q-R? 8:1 8:1 qT3Q 8:1 ^K2 -- -- — - — 0.51 (a)NaOH 5cc. 10 CO. r>:i 3K3 - 500 100 75 P. 0.34 0.6S (WHaSOi 5cc. 10 cc. 40 6:1 ^Tvi 500 500 100 100 #2 Euc. #750 P. 0.35 0.40 0.50 0.70 45 So 6:1 '^K'l NaOH 10 cc. 5:1 10 \6 500 500 500 100 100 100 #400 P. #75 P. #75 P. 0.47 0.34 0.23 0.27 2.'i 30 5:1 in A7 6:1 10 AS 0.34 0.07 NaOH 5 cc. 30 6:T 10A9 500 100 #2 Euc. #400 P. 030 15 35 5:T 3K6 -- -- -- - - 500 100 40 4'' NaOH 40 •l:T #750 10 cc. 0.90 3K7 .. 500 100 #350 P. 0.40 0.40 NaOH 20 cc. 5 cc. 1 40 0:T 3K8 500 100 *io p. 0.40 0.80 NaOH 20 cc. 10 cc. 35 6:1 3K9 500 100 #750 P. 0.60 (c)linie 61 gm. 1 30 4:T i 3K10 - - 300 100 1 • #750 P. 0.40 0.30 NaOH 5 cc. 5cc. 30 S:T 3K5G — 500 200 #750 P. 0.20 NaOH 10 cc. 20 4:T 1 1 1 (al 10% NaOH. goln. us?d in all tests wlicic noted. (b) Cone. HbS04 used. (c) Slaked lini" pasto. OriCKMI.VER RESOURCES. 307 FLOTATION TESTS. V Tailings Concentrates Character ami behavior of froth 3 M > s V S 3 Remarks ■3" h U "Hi g^ .J 1^ J i^ « w & < & < hH Thin; not persistent; small 0.3S 278 0.255 20 34 In Hyde machine. luil>liles. rair. but thin; small bubbles 0.38 277 0.22 21 43 In Hyde machine. Fair, but thin. B<>tter than pre- 0.3S 273 0.155 24 "2.55" 60 In Hyde machine. ceding one. Small bubbles. V"rv thin, not persistent. Small 0.3S 277 0.32 12 17 In Hyde machine. bubbles. Froth of emulsion subsideti on 0.3S 433 0.305 43 20 In Case machine. Oil addinp ore. Then, practically put in before ore. no froth till addition of more oil at 10 min. Froth thin. small bubbles, temporary, shallow. Froth thin, temporary shallow. 0.3S 47S 0.37 16 3 In Case machine. Oil Bubbles fairly large, but thin. put in before ore. and did not seem to carry any sulphide. Froth up immediately. but 0.3S 463 0.22 16 42 In Case machine. Oil slowly. Slightly thick, but not put in before ore. persistent. Small bubbles. At start, a few thin, large bub- 0.3S 463 0.15 11? 60 In Case machine. Oil bles, which broke quickly. After put in before ore. 5 min. adiled NaOH. Fair ?— sample pan leaked. froth, bubbles, both coarse and fine, somewhat persistent. Thick, persistent, deep, volumin- 1.72 403 0.77 94 55 Oil in before ore. ous. Bubbles coarse. Thick, persistent, deep, volumin- 1.72 454 0.69 42 60 Oil in before ore. ous. Coarse and fine bubbles. On adding ore, froth rose im- modiately. Thicker, deeper, coarser, than 1.72 444 0.63 46 ^ 63.4 Oil in before ore. preceding test. Tailings slow to set- tle: liquid milky. Froth up immediately. Thick, 1.72 415 0.635 68 63 Oil before ore. deep, persistent; large bubbles. In balance of tests. As the oil was used up, the ore put in before bubbles became smaller, but oil. still persistent. At first, a few thin, coarse, non- 0.3S 459 0.30 27 21 Tailings slow to set- persistent bubbles. After 12 tle. This ore con- min. addod #7.50. Froth thicker. tains much ochre. but small bubbles. Thin froth and small bubbles. 0.3S 412 0.38 49 Tailings slow to Thicker on addition of more settle. water: also deeper. A very little thin froth imtil 0.3S 450 0.36 31 5 Tailings slow to set- addition of more oil after 10 tle, in all tests using min. Then fairly deep and XaOH. persistent, with both coarse and fine bubbles. .\ rather good looking froth, but s?emed to raise but little sulphide. Very large, coarse, persistent 0.3S 500 0.35 25 8 After drawing ofT, bubbles: deep froth. Raised pulp settled clear in colloidal ochre, but no sul- few minutes. phide visible. Froth up. with sulphide imme- 0.3S 263 O.IS 2S 53 Froth not thick nor diately on adding oil. Medium persistent enough. deep ami thick: slightly per- but appeared b<>tter sistent. Raised some gangue. than with thicker Deeper after adding more oil pulp. and caustic. On adding XaOH. bofore oil. 0.16.1 461 0.165 25 Sample mad" up of froth uii innnediately (prob- "' (Total 2.50 grams, each. ably from oil retained in pulp 577c) from tails of #3K5 from previous charge). Deep and #.3X10 (see thick, some persistent: small above) — original bubbles. A little sulphide but head assay (iM% gangue also. Probably should Hg. A little cinna- not have added as much bar visible in NaOH or oil. coarser sand of dried tailings. M08 CALIKORXIA STATK .MIXIX(i BCRKAU. DATA OF FLOTATION Oil used I Other reagent adUeil Number of sample Kind 3Kn 3K12 8A6 SAT lOAlO 500 lOAll 500 ' 100 « Euf 10A12 300 100 500 200 500 100 490 100 500 100 500 100 Cal. Cr. #750 P. #750 P. #3 Evic. #75 P. #2 Euc. 300 100 10A13 300 100 10A14 lOAllK lOAllL 500 100 407 200 10A15 .--- -.1 300 100 10A16 -..! 500 200 Cal. Cr. #750 P. Amount " I -So _■ -c =^ At start 0.20 0.10 NaOH 0.40 0.30 5 cc. 0.50 0.20 0.30 0.05 XiiOH 10 cc. 0.30 i. 0.30 ' 0.10 0.30 I 0.20 #2 Eiic. 0.30 ' 0.30 #3 Euc. 0.30 0.70 300 100 #3 Euc. 0.30 0.70 #2 Euc. 0..30 #2 Enc. 0.20 0.30 0.20 0.40 52 Eiic. 0.30 0.10 0.20 0.20 XaOH 5 cc. XaOH 10 ee. 1 I ji ci I O 3 jH |_a. 1 30 S:l 30 4:1 .30 4:1 NaOH 5 cc. SO 4:1 45 5:1 .35 , 5:1 30 S:l 30 0:1 30 S:l 30 4:1 30 4:1 30 4:1 30 4:1 (d) Tn all t"sts. following, on OoMliank.* oro, somo siilpliiil^' float'Ml bnfore addition of oil. (e) Frotlis .f'M'nii'd to l)','i(niii> shallow, sooner, at lower .^pied: and concentrates cleaner witli thinner pulps. QncKSII.VER RESOrRCES. 309 TESTS — Continued. fli Tailings Concentrates Character anJ beliavior of froth say valu( i ». i 5 Remarks ■r. . K til lif 1^-- IJ *i 1^ ^ i"--^ 1 "1^ X & ■«! j? < M Cal. crude oil added after ore; 0.3S 277 0.145 16 5.40 62 At 30 min. still raising then #750; then froth up im- j a little concentrate. mediately. Froth t h i e k e r. : deeper: bubbles coarser; slightly more persistent, than without Cal. crude. Froth up immediately on adding 0.3S 453 0.155 24 5.0S 59 At 30 min. still raising oil. Thick, deep, fine and a little concentrate. medium bubbles, only slightly A very little cinna- persistent. Raising also some bar visible in sandy ochre with sulphide. part of tailings, un- released. Some bubbles and sulphide 0.49 400 0.07 80 2.96 86 Pulp settled quickly. before oil added. After oil. bub- bles mostly fine, a few coarse. but not persistent. .After 5 min. add'Pd XaOH-froth deeper, thicker and persistent. but raising some gangue also (less XaOH would suffice). 1 Some conc°ntrates before oil 0.49 434 0.11 40 ■ 1 78 A little cinnabar vis- added. After oil— froth up im- j ible in coarser tail- mediately. Thick, deep, coarse ings. bubbles, persistent. Some I gangue raised also. Some bubbles and sulphide be- 1.72 443 0.56 62 67 At 4.'i min. still raising fore oil added (d). .After oil. a little concentrate. deep, persistent froth, coarse bubbles. 1 Froth immediately, thick, deep. 1.72 430 0.46 71 i S.44 73 At ISC r n.m.(e). Only persistent. Also some gangue a litt'e concentrate raised, but concentrate looks after 25 min. cleaner. Froth thinner after adding more water. Froth immediately thick, deep. 1.72 270 0.575 26 63.6 At 13on r.p.m. Only a persistent. Fairly clean con- little concentrate centrate. Froth thinner just after 17 min. before and thicker after each addition of oil. Froth immediately thick, medium 1.72 2S0 0.67 IS 61 At 1300 r.p.m. At 30 deep and persistent, but not min. still raising as good as preceding test. some concntrat". Froth immediately: but deeper 1.72 274 0.64 22 63 At 1800 r.p.m. (See and more persistent than at photo #73.) lower speed. At .30 min. still raising some concentrate. Froth imniidiately; medium 0..r2 477 0.485 20 s At 1.300 r.p.m. Sample bubbles: fairly thick; deep. (Total made up of 2.50 gm. and some persistent. Some 72%) each from tails of sulphide but mostly gansue. #10 Ml and #10A12. Froth and concentrate before 0.4S5 331 0.24 97 49.5 At i;»0 r.p.m. Tails oil added (probably from (Total from #10A11K re- previous charge"). Deep, thick. 86%) ground to —200. persistent: bubbles, both fine After retreatment. and coarse. Raising dark part still some cinnabar of gangue, also. At 30 min. on coarser quartz. still raising some concentrate. though —200 mesh. Froth and concentrate immedi- 1.72 246 0.55 54 6S At 30 min. still raising ately on adding U7o(). Deep. some concentrate. thick, persistent: coarse bub- bles. Raising some gangue also. j Froth immediately. Deep, thick. 1.72 395 0.2.55 103 1 S5 At 1300 r.p.m. persistent; coarse bubbles. Some gangue up. 310 CALIFORNIA STATE MlXIXCi FMRKAl-. DATA OF FLOTATION a =1 S a CO O Oil used Other reagent added 1 'i Kind Amount At start ^ a. Niiiiiliei' of sample < Total added later, cc. "=■£ 0. lOBl 1 500 200 #750 P; 0.40 1 1 20 4:1 10B2 500 200 Cal. Cr. #750 P. 0.20 0.30 0.10 0.20 25 4:1 10B3 500 200 Cal. Cr. #750 P. 0.22 30 4:1 0.34 5:1 10B4 500 200 Cal. Cr. #75 P. 0.25 0.40 'o.io' NaOH 5cc. 35 4:1 5:1 12A2 500 100 #3 rue. 0.4(1 0.30 NaOH 5 cc. 5 cc. 30 5:1 12A3 500 100 Calol B. 0.50 0.60 NaOH 30 cc. 25 5:1 5cc. 12A4 500 100 #7.-.n P. #2 luic. 50 n 7>o NaOH 35 4:1 12A5 .. 500 100 0.50 0.20 10 cc. NaOH 05 4"1 5 CO. 12A6 SOO 100 tl Kiic. 40 10 NaOH 25 S:l 5cc. 12A7 300 100 #7r.n p. 0.40 0.20 NaOH 5 cc. 30 S:l 12A8 - 300 100 Cal. Cr. #750 P. 0.20 0.40 0.10 0.20 NaOH 5ce. 1 30 8:1 (f) 'l"«ilinK.>* from #liiHi-l()I?4 (inc.) showed some ciiinal)ar . Mnrl 1:-! Itl'llii I'lii/in- ^l^\ Wi.li.n- tris >^i.li.liiM' KoiiL- qnc KS 1 1 A KR RKS( ) I ' RCES. SIS- TESTS — Continued. Chanicter and bi'havUn uf fidtli Froth up iiiimpdiately. Deep, thick, persistent ; bubbles, coarse. Some gangue up also. Froth up immediately. Bubbles, both large and small but not as deep, nor as persistent as w i t h N a O H. Concentrate cleaner. Froth thin; medium bubbles; not persistent. Froth thin; medium bubbles; slightly more persistent than without NaOH. Raised some gangue. Thick, coarse, tough, persistent hubbl°s. Froth, medium deep. Sulphide raised, but much gangue also. Froth and concentrate immedi- ately. Thick, deep, persistent; hubliles coarse. Some gangue up also. Froth and concentrate immedi- ately. Thick. deep froth. Bubbles smallw and somewhat less persistent than thicker pulp. Froth up immediately, shallow to medium deep, some persist- ent; bubbles fine and coarse, tough. Clean looking concen- trate. Froth deeper on adding more oil at 15 minutes. Froth up immediately, shallow to medium deep. Fine bubbles swelling to large. Practically no froth. A few large, not persistent bubbles. Much water (?) skimmed over. Froth and concentrate up im- mediately on adding oil. Froth, shallow, thin, only slightly persistent; bubbles, fine and coarse. Cinnabar came up on top with pyrite just under- neath. Froth up immediately on adding «7.5: of medium depth, thick- ness, and persistence; bubbles, coarse to medium. Concen- trate appeared of cl°aner cin- nabar; less pyrite visible, ex- c"pt towards end of test. Some froth before oil. .-Xft-^r oil, froth thick, sticky, shallow, some persistent; bubbles, fine and coarse. Raising mainlv gangue. On adding fresh oil, bubbles immediately became coarse and kidney-like but quickly sul)sis. He also stated that they had found that a combination of crude wood tur- pentine with a crude asphalt-base petroleum would select cinnabar in preference to pyrite from a mixture of the two. This was verified by the writer with the Helen mine ore, (q.v.) 316 CALIFORNIA STATK MIXING BKHKAr. Some flotation tests were made by K. L. Beals^ on a sample of ore from the Bella Union mine earryin*; abont 0.7% mere\n-y. The results of three of his tests willi a Hoover type laboratory machine were as follows, the assays of his products having been made by the writer: "A — 500 gnims ore, r)000 c.c. water Coneentrate Jl, 11.2 grams IT.-i 'y Hg Coneentrate $2. 11.9 grams ].72 % Hg Tails +100 mesh 60 grams 0.07.5% Hg Tails — 100 mesh 230 grams O.O.". % Hg Tails unscreened 150 grams 0.075% Hg "B — 500 grams ore, 3000 c.c. water Oil — 10 drops of following mi.xtiire : 20 c.c. Whittier Fuller Pine Oil 5 c.c. Calol A 15 c.c. Calol C Concentrate 18.2 grams 10.28 % Hg Tails 50 grams 0.115% Hg "C — 500 grams ore, 3000 c.c. water 15 drops oil mixture used in B 15 drops pine oil Concentrates 6.1 grams 32. 8S % Hg Tailing not assayed. "Tlie idea of the tests was to see liow dean a tailing and how higli a concentrate covdd l)e produced the same to be obtained in a plant by the proper arrangement of machines." He noted that in flotation of low-grade material the best work was not done until a fair grade of concentrate had been built up, so as to ''have some body of sulphide to float." In a commercial plant this would be accomplished by the continuous process with several cells in series. A complete chemical analysis should be made of a material contain- ing so many active chemical constituents as does the Sulphur Bank ore, before one att(^mpts to work out an ore-dressing or metallurgical scheme for it. The cinnabar occurs to a considerable extent mixed with native sulphur in the leached basalt in the lower zone of oxida- tion, though the principal deposits are below this level. It is associated also with much silica, in part amorphous. As to the solfataric springs at the Sulphur Bank, Becker^ says: "Tlic gases escaping from the waters are carbon dioxide, hydrogen sulphide, sulphur dioxide, and marsh gas. The waters contain chlefl.v carbonates, borates, and chloride of sodium, potasium and ;immonium ; Imt alkaline sulphides are also present." As already noted herein, the moistened material of this sam])le tested, showed ;iM acid reaction with litmus papei'. Only two tlotatiou tests were made on this ore, both with negative results. l*racticall\- only gangue material was floated, resulting in the i-esidue yielding a higlier mercury content than the heads assay showed. AVith tlie Helen mine ore, the writer obtained fair results with both eucalyptus and pine oils, 'i'he highest extraction. S^o; ^yas with a eucalyptus oil, giving an 8 to 1 concentration, l)ut the c:)Mcentrate car- ried considerable pyrite. A cleaner concentrate, assaying 15.84% mer- 'Personnl communication to the writt r. '•Becker, O. F., fJcologx- of th<' (ini(k.sil\-ci- dopnsits of the racilic .>-;i c u t> X c o 10 «> h c _o « 3 a IS u o DC 1 *J Lt O) oo -r oc tc "M -» C; 5C "C iciM O Tc tc t^ r^ — rr '- rr (M ?? 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Also, oil consumption is less, especially if the water used be clarified and returned to the circuit. It seems to be not po.ssible in most cases to get both a clean tailing and a clean concentrate at a single operation with a laboratory machine. One may be obtained at the expen.se of the other. One or both must be retreated to obtain the final, desirable product. In commercial plants, several cells or units are operated in series, so that by the time the pulp emerges from the lower end it is supposedly 'clean'; and, in addition to this, a portion at least of the concentrates may be reeleaned. AVater utilized at the mine should be employed in the tests. In their admirable paper on labora- tory flotation manipulation, Ralston and Allen' have called attention to some of these eccentricities, if they may be .so termed : "None of tlie literature mentions the fact that it is difficult to get a high percentage of extraction and a high grade of notation concentrate at the same time. * * * It is difficult to manipulate a small machine to give as good results as a large one, until after considerable practice. So the small machine is generally pessimistic, compared with the large one. * * * ******* "Beginners are likely to dilute their frotli witli too much gangue. In a large-sized machine the froth can travel over from four to eight feet of spitzkasten before it is discharged, while in this test-machine [Janney] it only has a travel of about 10 inches. Consequently, the small machine is liable to yield concentrate of too low a tenor. The same applies to most other machines for making tests on flotation. ******* "If it is so desired, this rough concentrate can be put back into tlie machine and treated in the same way as tlie original sample, or the concentrates from several tests combined to give enough material for retreatment. If this is done three products are made, namely : "A 'rougher' tailing, to waste. "A clean concentrate, for shipment [or for immediate retorting in the case of cinnabar]. "A 'cleaner' tailing or middling, which in actual practice is returned to the head machine. "When these conditions are observed results only slightly lower than those pos- sible with a big macliine can be obtained. A test can be run in from 5 to 30 minutes in such a machine with ."lOO grams of ore in anything from a 3 ;1 to a 5 :1 pulp. * * * Clean tailings genei-ally mean only medium-grade concentrates due to entrainment of gangue in the removal of all the mineral. ******* "As a rule laboratory machinery for the pulverization of ore is of the dry-grmding type, with the exception of small ball-mills that can crush from 1 to 100 lb. charges in the wet. Consequently, most people start with weighed charges of finely-ground dry ore. a known quantity of water, of oil, and of acid or alkali. * * * In nearly all laboratory work finer grinding than is used in practice seems to be necessary. This may possibly be due to the smaller amounts of froth that are formed. Such small f(uantities of froth can not form layers as deep as those made in the large machines. If a big particle of sulphide can be entrained with a number of smaller particles, it can be floated, but with a thin froth the chance of sucli entrainment would seem to be less. Some experimenters have informed us that they were able to float even as large as 30-mesh material, but our own experience is that 60-mesh material is often hard to float witli any chance of getting a high e.xtraction, while the operation is performed with much more ease and expedition wlien the ore is crushed somewhat finer. "Wet grinding is more desirable, as it parallels conditions in practice, where most of the finer grinding of ore is in Chilean, tube, and other mills. However, wet grinding is harder to manipulate in a small laboratory and requires more time. * * * "The measuring and testing of flotation-oils in the laboratory has been very inexact in many instances witnessed by us. It is common practice to count the number of drops of oil falling from a small piece of glass tubing. We are using- a Mohr pipette of 1 c.c. total capacity for measurement of the amount of oil used in each test. * * * This pipette allows measurement of the oil to the nearest 0.01 c.c. ^Ralston, O. C. and Allen, G. L., Testing ores for flotation process: Min. & Sci. Press, Vol. 112, pp. 8 et seq., 1916. S20 CALIFORXFA STATF^ :\[rXIXr. BI'REAT'. which is as cluse as will ever he desired. If the density of the oil is known, the volume as measured by this metliod is quickly converted into the weight of oil ■used * * *. "Many reports of notation test-work witli mechanical-agitation machines give the speed of the rotation of the agitating-l)lades. We have found that it was possible to get mucli the same work done with (luite a variation of speeds, ilie only effect being to lengthen or slioi-ten the time of treatment. We feel that tlie importance of this matter has l)een much e.xaggerated. Some means of speed-conti'ol is necessary and the speed can be ad.iusted in each case vmtil the froth presents the proper appear- ance as to depth, size of bubljles, color, etc. Speeding towards tlie end of a test in order to give a deeper frotli with a faint line of concentrate on the very top is often advisable. We recommend adjusting tlie speed in each test to suit the other condi- tions, rather than i-imiiing a series of tests with different speeds. * * * "When a good set of conditions has been found for the flotation treatment of an ore. it is best to recovei- the water from eacli test to see what effect a closed circuit of the mill-water will have. Some oil and chemicals are thus recovered, cutting down the amounts necessary for operation. In fact, a car-boy or two of the water to be used in the large mill should be used to make certain that no deleterious contamina- tion will ensue from this source. Under these conditions filtration for recovery of the water is necessary. * * * "Finally, it is well to be prodigal in the amount of analytical work connected with flotation testing in order to discover interesting differences in gangue-constituents carried into the concentrate, as well as to find the best conditions for leaving out some gangue constituent that is less desirable than the rest. If an experimenti-i' does his own analytical work he can be expected to spend three-fourths of his time analyz- ing wliat has been done during the other fourtli.'" * (^ncKSIIAKK RESOURCES. 321 EXTRACTION OF MERCURY BY SOLUTION WITH Na.,S + NaOH. The solubility of mercuric sulphide in alkaline sulphide solutions has been known to experimental and industrial chemists for more than 100 years. The preparation of vermilion in the wet way, as described by Kirchoft'^ in 1799 is based on these reactions. Becker- reviews some- what in detail the literature relative to such solubility, and also describes a series of experiments made in his own laboratory along the same lines. These were carried out with a view mainly of shedding light on the source and nature of the solutions which brought about the deposition of the cinnabar ore-bodies found in nature. Obviously, such data would also be of value in an investigation of the reverse of the deposition, — that is. the re-solution of the precipitated cinnabar for its commercial recovery. He states that the solubility of HgS in Na.,S -|- XaOH solution depends on the quantity of NaoS present, not that of XaOH, so long as there is even a small amount of the free caustic hydrate present.^ "A very small quantity only of the hydrate is sufficient to sec-ure to tlie alkaline sulphide its maximum solvent power over mercairic sulpliide. * * * 'fhe greater part of the experiments made to test the maximum solubility of HgS in Na^S in the presence of NaHO shows that the relation of the weights of the two substances is very nearly in the proportion of one molecule of HgS to two molecules of Na-S." In the practical application, of course, a slight excess is necessary over this theoretical proportion. Among the more recent of detailed research experiments related to mercury sulphide, solution and crystallization, is the work of Allen and Crenshaw* of the Geophysical Laboratory, Washington, D. C. They state :^ "Any form of mercuric sulphide dissolves readily in concentrated solutions of sodium (20"^ NaoS and K^S were actually used) or potassium sulphitie. * * * The alkali sulphides form with mercuric sulphide two compounds. HgS.2M..S and HgS. M.S." According to Schnabel and Louis,'* these double sulphides contain "variable ciuantities of water according to the temperature and tlie concentration of the solution. A portion of these double sulphides is soluljle in water in the presence of caustic alkalies, but at a certain degree of dilution is decomposed again into its constituents." Some other proposed wet methods for the extraction of mercury are described by Schnabel and Louis,' including the method of Sieveking'^ which involves treatment of cinnabar with a solution of cuprous 'Kirchhoff. G. S. C in Allg. Jour, der Chemie, Scherer. A'ol. 2. p. 290. ^Becker, G. F.. Geologv of the ciuicksilver deposits of the Pacific Slope ; U. S. G. S. Mon, XIIT, pp. 419-437, iSSS. ■'■Idem. p. 4 22. *Allen, E. T. & Crenshaw. J. L.. the sulphides of zinc, cadmium and mercury ; their crystalline forms and genetic conditions: Am. Jour. Sci., Vol. XXXIV, pp. o4 1-396, Oct. 1912. •■Idem. p. 3 68. '■■.Schnabel and Louis. Handbook of Metallurgv. Vnl. IT. 2d ed. 190T. p. 332. •Idem, p. 439. «Oesterr, Zeitschr. 1876. Xo. 2; Berg- und Hiittenm. Ztg.. 1876. p. 161. 21— 3<.i40 322 CALIFOKXI.X STATK .MI.NlNc; HIHK.VC cliloride in the pre.sence of a granulated alloy of copper and zinc ; also the method of AVagiier.'' wliich involves the use of bromine water and hydrochloric acid. Tlie following tal)ulation by Abeyg'" gives the i-clative solubilities of the black ('schwarz'). amorphous mercuric sulphide and of cinna- bar in various strengths of Na^S solution, at 25° : Mol.* XfuS Mol. HgS (.^ohwaiz). Mol. HgS (zinnobor)--. HgS (schwarz) ) Zinnobcr \ NasS : zinnobcr 1.5 OJS' 1.0 0.46 0.42 1.09 2:1 1 2.04:1 0.75 0.31 0.27 1.12 2.8:1 0.5 0.175 0.15 0.375 0.111 0.092 1.19 1.21 3.3:1 4.1:1 0.15 11.023 0.018 ] :m\ 8.3:1 0.1 0.011 0.0086 1.29 11.6:1 *'Mol.' means gram-molecule. EXPERIMENTAL DATA. In the Avriter's experiments, a 10% solution was made up. with 'Baker's Analyzed' Na.S. 9ri.,0 crystals (moleculer weight 240.3). The NaOH solution used was also 10% being the laboratory reagent, of 100 gm.. c.p. XaOH per liter. The ore samples Avere ground to — 200 mesh, and a 10-gram charge taken in each case. In Test A, each was agitated with 20 cc. Na^.S and 0.5 cc. NaOH, for 20 minutes in a test- tube, then filtered and washed with three changes of distilled water. Total time of contact of solution on the ore was approximately one-half hour. In Test B, each was agitated with 20 cc. Na^S and 0.5 cc. NaOH for 5 minutes, then filtered, washed once with 5 cc. Na^S and finally with three changes of distilled Avater. Total time of solution contact 15 minutes. In Test C, each was agitated with 20 cc. of 5^ Na.^S (10 cc. diluted to 20 cc.) and 0.3 cc. NaOH for 5 minutes, then filtered and washed successively with Na^S and water. Total time of solution con- tact 15 minutes. The following tabulation summarizes the results: Test A Test B Test C Heiuls. per cent Hg. Sample* Residue per cent Hg. Per cent extrac- tion Sample Residue per cent Hg. Per cent extrac- tiun .Sample Ueftidue per cent Hg. , 1 Per cent e.\trac- tioii 1..39 7A2 8A8 9A2 10B5 12A9 13A9 15A7 0.31 0.05 0.02 (1.05 0.02 0.(12 0.97 78 90 91 97 85 96 45 (1.19 8A9 9A3 10B7 12A1() 13A10 0.095 0.015 0.36 0.02 0.05 81 95 79 85 90 0.31 1.72 9A4 10B8 12A11 1.3A11 0.12 1.16 (I.OS 0.21 69 33 (1.14 4S 0.50 58 I •7.4, Ksperanza min?; HA, St. John's; 9A, Cambria; lOB, Goldbanks; 12A, Bella Union dump; 13A, H"lla Union Jiiinc; 1,-)A, H"lfn. "Wagner, R. : Dingier, Vol. CCXXVIII, p. 254; Chem. Ceiitiallilatt, ISTN. p. 711. '".Abess, R. : IlandlMich drr AiKirsanisclicn Chcniie, Vol. 11. I't. L', p. (j:;2, IHOS. QUICKSIIA'ER RESOURCES. 323 In nearly all cases, more or less of a greenisli-blaek eolloidal precip- itate of iron sulphide was formed. Tt was es])eciall\' noticeable with 12A (due to the ochre) and in 7A and 15A (doubtless due to tlie pres- ence of soluble iron compounds, though there was no ochre in either. Both contained considerable serpentine). A piece of aluminum plate placed in the filtrate from 10B5 showed small globules of metallic mercury reduced upon it in a few minutes time. Some bright zinc shavings placed in tlie filtrate from 1()B7 showed no reaction up to 48 hours. In addition to the above. 10 grams of JflOB was agitated with 20 cc. of a saturated solution of Na^S and 1 cc. NaOH. for 10 minutes; then filtered and washed with one change of water. Total time of solution contact approximately one-half hour. A large amount of the colloidal, black sulphide was precipitated, and made filtering very slow. The residue asayed 0.18% mercury, or an extraction of 90%. Evidently the residue was not completely washed, as it showed more mercury than the test witli 10% NajS. A test was also made on a sample of Sulphur Bank ore (#18A2), —150 mesh, with 20 cc. lO'/r Na.,S and 0.5 cc. NaOH. agitated 10 minutes ; then filtered and washed with two changes of solution and three of water. The residue showed no extrac- tion, though the sample carried 6% mercury; but there was an abund- ant, black, iron sulphide precipitate, which apparently took up all of the available Xa^S in the solution. Possibly this might have been obviated by a preliminary water-wash of the ore. As noted under the • flotation experiments, a complete chemical analysis should be made of such a material, to intelligently work with it. With longer solution contact than given in the above tests, even 1 fairly coarse, crystalline cinnabar will be dissolved. Some — 80-mesh concentrate (from Helen mine ore) left standing without agitation in a test tube was completely dissolved after three days. The ])yrite present was apparently not aifected. PRACTICAL APPLICATION OF THE XaoS SOLUTION METHOD. Though it has been suggested at various times, to date there has been no application of this method on a working scale to natural mercurial ores. In 1911. ]\[ulholland'' proposed to fine grind the ore in a ball mill with the solvent — alkaline sulphide containing free alkaline hydrate; and to recover the dissolved mercury ]iy adding zinc hydrate in exce.ss to the filtered solution, "when zinc sulphide and mercuric sulphide are precipitated." * * * The barren solution mav he regenerated bv H.S. "The mixed precipitates are * * * treated with dil. H.SO, and steam." H.S being evolved. "On treatment with IL.SO,. zmc sidphide goes into solution as zinc sulphate, and there remains behind a mixture of mercuric sulphide and metallic mercury. This precipitate is mixed with, lime and iron turnings and distilled m a retort in the usual way. * * * It is, of course, possible to treat the sulphide lifiuors containing the mercury by electrolysis, when iMulholland. C. A., Treatment of low-grade cinnabar ores; Australian Mg. Sfd. June S, 1911, pp. 565 et seq. 324 CALIFORNIA STATE MIXIXG BL'REAU. nieriuiN' will be (lepi>siir'." Later'- in a discussion of the reactions involved, he contends: "a propel- concentration of sodium sulpliide and alkaline hydrate being necessary to the complete dissolution of HgS : the reaction outlined may be thus rept esenteJ : 2 NaoS + HgS + H.O ^ ^ Xa,. HgS,+NaSH-uNaOH "Under var.ving conditions f)f dihition and tempeiature the reaction is reversible; hence the necessit.v for caiefully determining the.se points b.v at-tual tests on the ore to be treated." Various other investii^ators^-' have stated the reaction tn he repre- sented l)y the ecpiation : lloS + Na,S == HgS.Na,S or hy : IlgS -f 2Xa,S = HgS.2Xa.,R. The only commercial api)lication of these reactions, of record to date, is that at the Buffalo Klines, Cobalt, Ontario, Canada, and described by Thoi'iihill'^ in 101."). In this case, liowever, the process is utilized to recover an artificial mercurial product. In the amaluamation of hiyli- grade silver ores and concentrates in strong cyanide solution, as prac- ticed there, the (piicksilver losses proved to he rather hi'^h. Chemical investigations revealed the fact that in addition to a certain loss due to flouring, very appreciable amounts of (piicksilver were converted to the sulphide hy the gi'indiiig contact willi the sil\-er sulphitles. (The writer has seen inereiiric sulphide formed, in the laboratory, by grind- ini;- (piicksilver and Hour sulphur together in an agate mortar, dry.) '=Mulholland, C. A., Wet m.thod of niercurv extraction: Min. ii;- .Sci. Pre.s.s, Vol. 111. p. 34 6, Sept. 4, I'M."). loj^Mg below, and p. 31' 1. . lHl->; .-ilso. Recovery ol mercur.v fi'om amalgamation tailing: Am. Inst. .Min. Kng., I'.ull. KM. pji. 1 G."i3-1 1!.");, IHl."); and Min. i«i Sci. Press, vol. HI, pp. Jll-312, Aug. 7, 111).".. QUICKSILVER RESOURCES. 325 ""The process developed at the Buffalo mines for this purpose consists in leaching out the mercuric sulphide with u caustic alkaline sulphide solution, then precipitating the meiiury from solution with metallic aluminum. The equations for solution (1) and precipitation (2) are: HgS + NanS - HgS.NaoS ( i ) 3 HgS. NaoS + S NaOH + 2 Al = 3 Hg + 6 Na-S + 2 NaAlOs + 4 HoO (2 ) •'Small-scale experiments showed that a complete extraction of the mercuric sulphide could be made by an ^ to 10 min. treatment of the residue with the alkaline sulpliide solution. Advantage was taken of this fact in the commercial plant, by applying the solvent to the residue on the fllter-leaf. as no agitation of any sort was required. "The operation of the commercial plant is essentially as follows: The residue in the pregnant cyanide solution is caked on a Moore filtei'-leaf of the usual construction and the cake washed free of silver solution with water. The basket is then lowered into the sodium sulphide solution and this solution drawn through the cake until the effluent shows only a trace of mercury. Usually 1 ton of solution ^er ton of residue is sufficient. This mercuric sulphide solution is pumped to a precipitating-tank and the mercury thrown down by adding granular aluminum to the agitated solution. Agitation is then stopped, the precipitate allowed to settle, and the clear .solution decanted. The precipitate of mercury is then run into a small wash-tank by sweeping it through a hole in the bottom, by means of a raking mechanism similar to a Dorr thickener, pieces of old rubber belting being riveted to the bottom of the rakes. The precipitate is then washed with water by decantation and drawn off into a steam drying-pan. After drying, the fluid mercury and the powdered metallic portion are separated by raking the latter off with a hoe. The fluid is strained through a canvas and is ready to return to the circuit. The powdered material, containing approxi- mately 75% mercury, is then retorted, and the mercury condensed in the usual manner. "The strength of the solvent is kept up to 4% sodium sulphide and 1% sodium hydroxide. Weaker solutions can be used with equally good results, but the quantity required was found to be directly proportional to the strength ; that is, with a 4% sodium sulphide solution, 1 ton of solution would extract the mercuric sulphide from 1 ton of residue, but if a 2 doul)le salt of mercur,\- sultid and sodium sultid will pi'ocipitrUe metallit' mercury, regenerate sodium sullid, and dispose of tlie ahnniiuim and clu-omiuni as ahuniiiates and chroma tes. ****** « The addition of lime precipitates the alumina te as an insoluble calcium aluminate and regenerates caustic soda. In a simple liydrolysis the sodium aluminate will break up regeneratins' caustic soda and alumimim li.\'diate. "Theoreticall.x-, -one (1) pound of aluminum will precipitate eleven (11) pounds of mercury, but practically one (1) pound of aluminum will precipitate seven (7) pounds of mercury due to the fact that some hydrogen is given off during the precipitation. Interfering Elements. "l.,ini produced. <3) Higher extraction possible. (4) Ability to work ores of a lower grade. (5) No danger of salivation to workmen. (6) Less time to make the original installation. (7) No mercury ab.sorbed or tied up in dust cliaiiili. See also p. 211. tiiitf ; and reproduced in I Ik.i-.. with lliH ciiiisi-'nt of both iiartics. QUICKSILVER RESOURCES. 327 "On a basis of a 100-ton plant working: on a 10-pound-per-ton mercury ore, we estimate tliat the cost of production will he appi-oximutely ten cents (lO(') per pound for the metallursical treatment only; the minins will, of course, be independent of the milling lost. This includes all costs, ovcihead, etc. We ha\e reco\'ered about €0,000 pt)unds of mercury in Canada diu-ins the past IS months at a cost of IS^* per pound but have treated only a small tonnage dail>' and there has been a large chemical loss due to the ore or i-ather concentrate containing- from 20'X. to 25% arsenic, ri'/, cobalt and nickel, and 5% antimony together with varying amounts of other metals. The mechanical loss was also larger than it should have been due to arrangement of Hlters. While it is not proper to attempt to make a direct comr'ari- son in costs with the plant in Canada, still it acts as a check on estimates. ******* "The costs as shown b.v your operations are from two to three cents less than my estimates of the cost for treating by the wet method. Not taking into considei ation the difference in e.xtraction, the furnace method shows a less cost per poimd proiluceil on your grade of ore than what I think can be done by the method I li;ive outlined ; however, the additional extraction will offset this difference in costs. For instance, on a basis of 5 Of per pound mercury, an additional extraction of 3 lb., which is entirely probable, will entail a charge against a furnace method of 37..5-=-10 = .3.75(! per pound, bringing up the real cost of the furnace product to 7.44(? + S.TS^,' = 11.19^ per pound on a 10 lb. ore. Nevertheless, your figures are facts and mine are estimates, although I am certain that I am within the limits. Since receiving your letters, I am inclined to be pleased that my estimates are so close to the figure that it is actually costing to produce in a vicinity whicli I presume has the lowest costs of any in this California field. I should venture the opinion tliat your location being favorable would be inducive to lower cost for labor and supplies. "I am submitting for your perusal my estimates of the different operating cost items which would prevail in a mill using the wet method, these being outside figures. WHiile fine grinding would be necessary, it will not be relatively as costly as in the case of such reduction for cyanidation of gold and silver ores, for the reason that we have found that the leaching action is relatively fast and the cinnabar seems to be exposed to the action of the solvent before it (the ore) is ground to the same degree of fineness as are gold and silver ores previous to cyanidation. "Estimated Milling Costs. (10 lb. ore) "40C per ton Coarse & Fine Grinding (including power, repairs, etc.). ton Filtering. ton Chemical Loss. ton Mechanical Loss. ton Repairs & Renewals. ton Precipitation. ton Oveihead Expense. $1.05 per ton Total Operating Expense. .$1.05 H- 10 = 10. 5^* per pound for 10 lb. ore. (50 tons daily.) ******* "I am certain that this price is an outside figure wlien leasing the selling price of mercury at its base price of approximately SOf* per pound, upon which we make all of our estimates. At the present time [November, 1915] scrap aluminum is selling some- what higher than in normal times and tlie precipitation expense is larger, but under normal conditions with scrap aluminium at 2^!^ per pound, tlie precipitating cost is about gc" per pound of mercury precipitated. The last quotation on tliis scrap was 7( per lb., so that the cost now would be about 2(! per pound of mercui-y. "In my opinion, the additional extraction po^;sible would more than offset the difference in the cost of fui'nacing, at S( per pound as against an outside figin-e of lO^! or even 12(' with precipitation at a higher cost at the same time. I am reasonably sure that a wet method would make an additional extraction of i lb. of mercuiy, which at present prices wovdd be worth at least TSc* and on a basis of a ten pound ore would create an additional charge, against each pound of the 90% saved by the furnace method, of lh(. making the real cost as compared to the apparent cost, some- where near !'>(: per pound of mercury produced. I feel that I am .iustifiecl in assuming that this additional amount of quicksilver will he saved since all of our tests on ores from California, Arizona, Nevada, and Texas sliow that a practically total extraction is an economic possibility in addition to the fact that in our eighteen months' operating in Canada recovering both metallic and chemically precipitated quicksilver, we found that our tailings assays from the filters invariably were a trace; checks against our assays for the entire period by means of actual knowledge of the amount that we used in amalgamation process showed that our losses were less than a quarter of a pound per ton and most of this was dissolved loss as our installation did not permit of a thorough displacement of the pregnant solution of mercury. In an installation of a reduction plant for a commercial mercury ore pi'oper means could ))e taken to prevent an excessive loss of any dissolved values and hence pro- vide a large saving. I am aware that my assertion of such a high percentage saving is taken by many people with 'a grain of salt' but actual practice and testing bears the statement out. The mechanical difllculties of filtering is the problem as the dissolution of values is readily accomplished. "You will have notii-cd from the theoretical eciuation that there is a regeneration of the solvent Na-S to twice its former strength due to precipitation of mei-cury. This is accomplished at the expense of the caustic soda. Sodium aluminate is generated but lime added or Vjy means of lime in the ore the precipitation of the calcium as calcium aluminate and regeneration of tlie caustic soda really makes the loss of caus- tic soda 1/10 11).; caustic soda sells for Sf* per -poimd. We have found one ore which approaches this theoretical vei-y closel.v. There aie some ores high in ar.senic which we covdd not treat; 12 or in lbs. of "lu'diated ii-on" is beneficial, more is detrimental. lOf per 15<' per 15C per IOC per 5C per lOt* per 328 CAUFORXTA STATE :\ITXTXG r:rREAT'. "I think iliat \i)ii will asi'Pf with me wlien I say that any ore irrespective of its metal content will have tlie same meclianical costs to be charKetl asninst it for reduc- tion to its i-eciuireci (Icjjrce of fineness in order that its contained min(>ral may be subjected to the action of the solvent ; then the additional charge to be made against any added metal content will be the cliemical charge. Tliis actually amounts to but- 1/io lb. of I'austic soda for every jjound of mercury precipitated, so tliat tlie additional cost of treating an ore ten pounds in t'.xcess of any other ore at hand will be but SC. Otlier ingiedients in the ore whicli might be harmful to the solvent will exercise their harmful effects regardl(>ss of the metal content of the ore in mercury. "Of course, there would be no additional charge per pound for additional pounds of mercury produced in a furnace, but the difference is very slight in any case. For this reason, while I believe that tlie greatest field will be in mines of a lower grade tlian it is possible to treat at present by the furnace, I do not concede that the slight additional cost of recovery per pound of mercury from the lowest grade it is possible to treat at present by means of a furnace to any number of pounds per ton aV)ove this amount, will be a valid argimient against treating higlier grade ores. "I am aware that a wet process Is not a pana-^ea for all the ills of mercury pro- duction and wish to ascertain its limits." ELECTROLYTIC DEPOSITION. Tlie present prices (November, 1917) prevailino- for aluminum, though about one-third less than the market prices of November, 1915, noted by Anderson in the foregoing quotation, are still above the normal pre-war level. There would appear to be a field for investiga- tion as to the applicability of electrolytic deposition of the mercury from the alkaline sulphide solution. The writer would like to have undertaken some research work on this phase of the subject, but the necessity of getting the main features of this report printed at as early a date as possible, prevented. The advantage would appear to be with the aluminum method of precipitation because of its regenerative fea- tures M'ith respect to both the Na^S and the NaOH. Whether an electrolytic method would have similar regenerative features seems not to have been determined, as yet. Dr. Duschak of the U. S. Bureau of Mines, Experiment Station, Berkeley, informs the writer that he hopes to undertake an investigation of this phase of the subject, in the near future. Electrolytic deposition has been suggested by jNEulholland,^^ and by Schnabel and Louis -^^ "No attempts have yet been made to extract mercury electrolytically. * * * jt must, however, be admitted that cinnabar is readily soluble in solutions of alkaline sulphides containing caustic alkalies, and that the electrolysis of the solutions of mercury sulphide and oxide thus obtained should offer no difficulties, and would not re(|uire an.v very high electric tension. "According to Brand, ^"c'innabar is readily decomposed at the anode of an electric current, whilst mercury is thrown down at the cathode, a solution of common salt or dilute hydrochloric acid being employed as a bath. The tension in the bath is said to amount to 1 volt. Tlie power to extract 1 kilogram of mercury in this way would accordingly amovmt to 1 volt X 2 66.5 amperes „ . , , - ^rr, .» ,^~^^ = 0-51 horsepower per hotu-, 650 watts X 0.7;) since 266.5 amperes can deposit 1 kilogram of mercury per hour, and since one horse- power, assmning 12'/^ of lo.ss in conversion, would yield not 7;!5, but 650 watts, and since the loss of current by conversion into heat, bv short-circuiting, etc., amoimts to 2n'/,. * * * A. V. Siemens ( Kng. I'at. No. 712:?. April 1, 1896) proposes to con- vert mercuric sulphide (like the suliiliide of antimony and arsenic) into a soluble double sidpliide b\' treatment with sulpli-hydratcs of calcitmi, bariimi, strontium, or magnesitmi, and to electrolyse this witliout diaphragms. In this way tlie lixdrogen lilierated at the cathode coniliines with tlie sulphur of the mercui-ic sulphide, setting free mercury and forming tlie sulph-liydrates of calcium, barium, strontium, and magnesium, which latter are then converted into bisulpliides by the oxygen evolved during the electrolysis. * * * This process lias not found piactical application." "•See p. 323. (rntr. '".Schnabel & Louis: Handbook of Metallurgv. vol. II, 2d ed., 1;mi7. p. 4tO. -"Damnier, ("lieiu. Tei lmoloj;ie, vol. II. [i. 11. t^UlCKSlLVEU UESOUKCES. 329 PRACTICAL APPLICATIONS OF CONCENTRATION TO QUICKSILVER ORES IN CALIFORNIA. Quicksilver operators, particularly the older men, have until (piite recently almost uniformly maintained that "you can't concentrate quicksilver ore." From the .standpoint of relative density, it does not appear reasonable that cinnabar cannot be successfully concentrated, having a specific gravity (8.0) practically double that of chalcopyrite (4.2) which is also quite friable, and nearly double that of pyrite (5.0). Both of these others are economically recovered by concentra- tion in various tonnages at numerous mines all over the world, the former for its copper contents and the latter for gold values. This skepticism was voiced by Egieston, in 1890 :^ "Generally the ore. as it comes from any of the mines, is more or less hand-picked. The attempts which have been made to treat the ores mechanically have usually not been successful, as cinnabar is so friable that more floats off with the water than is concentrated ; the most successful machine has been the Frue vanncr. * * * It is doubtful whether the concentration by any of the methods now in u^e, except a moderate amount of hand-picking, will be worth making. No concentration of the tine ore has as yet been successful." This, too, notwithstanding the statement of Hanks- in 1884, relative to assays for mercury : "The best practical test, especially for the prospector, is to use the horn spoon, and treat the pulverized rock as for gold. If the rock contains cinnabar an intensely red powder fringing the residue, will be obtained for a 'prospect.' If in a metallic state, minute globules will be the result. After a few trials the prospector will feel the utmost confidence in his assays, and will decide at a glance whether his ore con- tains mercury, and approximately the quantity. The best vessel for this assay is the batea, * * * if there is a particle of cinnabar present, it will be found at the point of the prospect, clearly distinct from all other substances." Richards'* states that at Idria, Austria, "wet crushing was carried on from 1694 to 1842 when the losses were found to be too great" and a system of stage-crushing, trommel-screening, and picking on belts substituted. He also summarizes the wet concentration method in use in 1895 at the Cornacchino mine, Tuscany, Italy, which is described by Rosenlecher.* The following descriptions are taken up in approximately the chronological order of the plant installations. The fir.st recorded practical concentration of cinnabar on a com- mercial scale in California was at the San Carlos mine of the New Idria company in San Benito County, in 1871. The ore then mined consisted largely of 'tierras' (tines^). "chiefly from a soft, somewhat decomposed clay rock, which is impregnated with cinnabar, * * * Nearly all the material mined here now crumbles to a mass of earth. This earth is first packed by donkeys down to the San Carlos Creek, where it is concentrated by washing, after which the tierras so obtained are hauled to the New Idria hacienda." 'Egieston, T., Metallurgy of ."Silver, Gold and Merciny in the U. S., vol. IT, p. 804, 1S90. =Hanks. H. G.. Cal. .State Min. Bur., Report IV. p. .332. 1SS4. Richards, R. H. : Ore Dressing, vol. I, p. 481, 1905; vol. II, p. 1074, 190.5; vol. IV, p. 1919, 1909. *Ro.senleclier. R., Description of the method of dressing quicksilver ores in Tuscany bv u.se of trommel, hand iig, hand picking and tie: Berg. u. Hiitt. Zeit., vol. LIV, p. 373, 1895. ■■•Goodyear, "^^ A., Report on examination of the quicksilver mines of California: Geol. Sufv. of Cal., Geol. vol. II, p. 120, 18 82. 330 CALIFORNIA STATK .MIX IXC BL'REAU. it is not stilted what a[)i>liaii- states" that the mill treated from two to five tons of ore per hour, the concenti'ates averaging 'So% quicksilver (often as high as ()8%), "wliile the tailings for several months' mill- "Ravmond, R. \\'.. Statistics of mines and mining in the states and territories west of the Rockv Mountains: Report VlII, for year 1S76, p. 19. 'Miller, W. P.. in Repoit X of Slate Mineralogist, p. TIG, 1890. "Northev, O. \'., Concentration of linnabar ores: Kng. & Min. .Tour., vol. 96, pp, 7.S3-7S4, Oct. 2."), I'tl.'). "F'orstner, Win., Quicksilver i-esourie.s of California: Cal. State Miii. I!ui-., Hull. 27, pp. 4ii. 19.S-2((L', ]90:!. '"Hradley, W. W., Mines & mineial res. of Colusa et al. counties: Cal. State Min. Bur., chapters of State Mineralogist Report, 1913-1914, pp. 17-18, 1915; also in Report XIV, pp. 189-190. 191(,;. "0/(. (it., p. 7S:!. QU1C'K81LVKK KESOURCES. 331 PLATE XL. Plan and e ley a Iron of Concentrating System, Manzanita Mine . a= Crusher b - Hu n t ingto n Mill c.d= Bumping Tables e= Tailings Concentrators f = Elevator 3- =^■•■0 c --♦ -• D ing averaged from 5f-10f'- jjer ton." The dried cpneentrates, mixed with 10%-25% lime, were retorted. The cost of milling is stated to have been 60^ per ton of ore treated, including fuel, wages, deterior- ation, etc., except office expenses. Under some favorable conditions the cost of milling was reduced as low as 25^ per ton. This low cost applied to ore that occurred in the form of sand, the connnon name in the camp being 'I)r()wn sugar.' The average value of the ore was a])out $5 per ton, or about 0.5% quicksilver. Additional data with refer- ence to this ])lant are given herein, under the head of retorts.'- The Cerise Gokl Mining Co. early in 1917. took over the ^lanzanita mine and the adjoining Cherry- gold mine, and has .since built a mill to extract the gold from the ores of both. Later, it is intended also to recover the quicksilver, by concentration of the cinnabar. »==See pp. 210-212. ante. 332 CA1>IF()KNIA STATK .MINING BIKKAU. At the Socrates mine,''' Sonoma County, during 1908 and 1909, the Socrates Development Co.. opei-ating the ])i-o])erty under bond, made a small outjiut of quieksilver, emi)h)ying a Huntington mill and a Wood- bury coneentrator. The concentrates were retorted. The Socrates ore is characterized by a considerable proportion of native quicksilver. At the Elgin mine, Colusa County near the Manzanita mine, some production was made in 1908-1909'^ with a Griffin mill and Colorado bumping tables. A few fiasks of quicksilver in 1916 are stated to have been made by concentration on surface ore. The above-mentioned accomplishments of Northey were largely ignored or overlooked, until TJ. P. Newcomb in 1913 began concentrat- ing the dumps at the Oat Hill mine in Napa County, and whose work AvavS described by the Mriter.^'^ During the summer of 1913, Newcomb had in operation one New Standard concentrating table (Llewellyn Iron Works, Los Angeles), as a trial plant, screening, sluicing, and concen- trating material from the old, low-grade, mine dumps. Later, he added two more tables and a revolving screen, with a 5 h. p. distillate engine to drive the screen and a 1^ h. p. for the concentrators. With two tables operating one 8-hour shift daily, handling an esti- mated 10 tons each per shift or a total of 600 tons per month, Newcomb states his cost figures to have been : Overhead $175 Labor (2 men) 160 Gasoline and oil 15 Miscellaneous (including wood, powder, horse feed, etc.) 50 Total per month $400 This is equivalent to $0.67 per ton of ore handled ; and the yield was approximately 16 flasks (1200 pounds) of quicksilver per month. This 2-table plant cost him $1500 installed, including a two-pipe retort. The dump material was ground-sluiced to 500' of riffled (1") wooden flume, 12"xl2'''; then over a 1" grizzly (to discard the coarser material) : then through 2 rifHed Hume boxes (25') ; then over an 8-mesh screen, and the fines sent to the concentratoi's. Occasionally a stick of 15'/(' dynamite was used to loosen the dump. The concen- trates yielded an average of 10 flasks of (piicksilver per ton retorted, or 37.5%. Newcomb tried several difl'erent grades, but found this to be a good material to retort; and, at the same time, l)eing not too clean saved the values on the concentrators witli a minimum loss in the tail- ings. With a somewhat lower grade concentrate he found the tendency of the concentrate to pack, to such an extent that it was difficult to I "Bradlev. W. "W., on. fit., p. ITS: nlso Cal. ^Fin. Biir.. Report .XIV. p. SfiO. 11116. "l(\lfi. '"Utiut. pp. 118-irj; also Report XIV. pp. L'Ihi 2!M, 1 ;t 1 1!. QUICKSILVER RESOURCES. 333 expel all of tlic (iiiicksilvei-; while at the other extreme, a piwe eiiina- bar would entirely volatilize, leaving no residue. To get the latter, however, cinnabar would be lost in the concentrator tailings. He esti- mated that he eould hatidle at a profit material carrying as low as 0.15% mercury (3 pounds per ton). The ore being a friable sandstone with impregnated cinnabar, and having lain out iu the weather for some years, it is more or less disintegrated and air-slaked, requiring little or no crushing; so that it is particularly favorable for low-cost concentration treatment. On the trails and roadways about the Oat Photo No. 74. Neill Jig, and New Standard Table, in plant of Oat Hill Leasing Company, Oat Hill Mine, Napa County. Hill mine, after a rain, cinnabar can be seen concentrated among the rocks and small crevices of the water-courses. Later (1915), Newcomb sub-leased the property to the Oat Hill Leasing Co., who increased the equipment and operated up to July 1, 1917, on a larger scale. They started with a Neill jig and a single New Standard Table at the #1 B. Fanny and Eureka dumps, (see Photo No. 74) later adding two more tables; also, later putting in a similar jig and two-table plant on the ^lanzanita dump. The dump material was gi-ouud-sluieed to and through 400'-50()' of riffled launders {12"xV2"). The riffles were made up of 1-iuch angle-iron 834 CALIFORNIA STATE MINING Bl'REAU. PLATE XLI RIFFLE UNIT OAT HILL Ml M NAPA CO., CaL. e* in. ///7,U- 3Jn. -^ J/rt. -^ 3/n. -*U- J/n. -A*- Jin. -»|^ 3 in. Jin. -*| 2 in. [*- One-e/ff^tfy inch ong/eiron throughout. ri 1 II 1 1 ll '1 Ml HI ll 1 II 1 II II 1 ll 1 ll 1 I ■< -« f/n e 'J J i; ] . 1 1. . .1 ] H 1 i II I ii ' ^ ^' 1 Ll__l 1!-_L a_ _l u. 1 il 1 LL_; -ii -^//>7-|*- .5 ^ccompani/ing 3u//etin Mo.7S, Ca/ifornio State A^inin^ BureatJ. (see Plate XLI). Considerable of the coarser cinnabar was caught in the rififles, besides which they also served to break up the clay lumps. At the end of the launder and just above the Neill jig a revolving screen with ^-ineh round holes reejected the larger sized pieces, and ^vas at first expected to also break up the clay lumps. The riffles, however, proved more etfective for that purpose than the trommel. A J/' screen was used in the jig with small steel balls to form a bed, the underflow of which went to the tables. The bed of the jig was cleaned up every 3 or 4 days. It seemed to tlie writer that the jig was over- crowded — too imicli pulp and an excess of water. Considerable fine pulp boiled over the top and went out a riffled discluirge launder to the waste dump. The writer panned n good 'prospect' from some of tiii.s discluirged pulp. Without doubt this jig can perform an cfoiiomic service in such a place when given a fair chance, as it has ])ioveii a profitable instalhition on gold dredges'" in Calit'ornia ami on tin drediics in Ahiska. With the one tal)h' as at first installed, an average of 500-600 pounds of concentrate was made i>er 24 hours, assaying 20'/f mercni'N-: and retorted in 2-12" pipe i-etoi-ts, 225 pounds being eliai'ged pel" S houi's. This ])lant was (iriven by a Ki h. p. West- ern gas engine, Ijater. a 'D' retort was installed, with a condenser system eonsisting of a (i" pi|)e. two wooden boxes, 2' x 3' x ()' and '"Edd.v. L. If., JJKs (111 a Califnrnia .IrccU Jan. 2!», 1916, KiiK. & Min. Jmir., vol. IiH. pii. 207-208, QUICKSILVER RESOURCES. 335 2'x3'x-i' and a sinall lilower. ]\ranzaiiitH. madronc. and oak are the available fuels. An iindereurrent li'rizzly 5' long-, with !|" opening- is plaeed in the launder line of the plant on the ]\Ianzanita dump, to reject the coarser material ; hut no revolving- screen was used as at the other plant. The Xeill jig and two tables were driven by a 5 h. p. Standard, distillate engine. In the ravine below the Manzanita dump, the le.ssees had, in February, 1916, three men working with rockers, concentrating material which the rains had washed down from the dump. A fair amount of cinnabar was thus recovered. Photo No. 75. Gilpin County (Colorado) Bumping Tables in Mill at JEtna Mine, Napa County. September, 1913. As the Oat Hill mine dumps have lain out in the weather for some year.s, the erosion of winter rains has naturally concentrated consid- erable material from them into the g-ravels of James Creek and its tributary ravines below the dumps. Lindblom Bros., leasing on land on James Creek, owned by ^Mrs. ]\I. Patten, with two rockers were able to make 30-40 pounds of concentrates per 8-hour day. This yielded 30%-- i09( mercury in a retort consisting of two 4" pipes. In 1915 and 1916 there were several others operating similarly, in a small way with roekers, farther down on -Jame.s Creek, near Aetna Springs. Among these were: A. ^larro. Joe Faulishich, Bert and Henry Wells. 336 CALIFORXI.V STATE MIXIXG BFREAU. At the Wall Street iniiie. Lake County, wlifii visited by the writer'" in 1913, there was a small Chilean mill and two homemade table-eon- centrators said to liave a eapacity to handle 3i tons of ore per day. ]\[ore recently (September, 1917), the owner reports that he has a small-size Deister concentrator. Some of the soft ore is concentrated, but the hard one is retorted direct. At the ^tna mine, Napa County, Broi- Soderhjelm, lessee, built a concentration plant, which when visited ])y tlu^ writer^'* in September, 1913, was "tqnipped with a Dod^e crusher, Griftin mill and six Gilpin County bumping: tables, (see Photo No. 75) the whole Vieing operated by a 40 h.p. distillate engine. It was observed that the Griffin mill made a considerable proportion of slimes. The Gilpin Count.v bumpers seemed to collect most of the coarser cinnabar, but lost the fines. As already pointed out, it is very important to avoid sliming of cinnabar, as it is e.xtremely friable. The use of a common power unit for both crushers and concen- trators is also objectionable for effective concentration, on account of the variations of speed caused b.v the rock breaker. Having discussed these points with Mr. Soderhjelm at the time above noted he writes, under date of January 23, l!tl4, that he has taken out four of the bumpers and put one New Standard (Llewellyn Iron Works, Los Angeles) table in their place, 'but the Standard table had too much to do ; so I have ordered another, and if that is not enough I wmU have some more of the same kind, as the Standard seems to take kindly to the slime.' Also, the concentrators are now being driven by a. separate 5 h.p. engine. Ore from tlie surface cuts is soft and clayey while that from underground is in part hard and siliceous. The capacity of the mill is stated to be 64 tons per eight hours. An 18-mesh screen is used on the Griffin mill. The concentrates are reduced in two 'D' retorts, arranged with both a fan and a water-jet for draught. In the same letter above quoted : 'I found tliat lime was not so good as charcoal with air in the retort, and I have to use lots of it too, besides shaking it up two or three times." " Soderhjelm continued operating this property, treating material both from the mine and certain of the old dumps, until some time in 1915, when the lease was taken over by other parties, with A. A. Gib- son as superintendent. The Soderhjelm table tailings had been impounded on account of the slimed cinnabar contained, A sample from these tailings was utilized by the writer during some of the tests described elsewhere herein (see p. 287, ante). At the time of the writer's visit to the Aetna mine in February, HUG. the crushing plant Avas not in use, but some of the concentrators were in operation. Two Colorado bumpers and one New Standard tal)k' had been transferred to the '#7 Silver Bow' dump, the material being ground-sluiced to them thi'ough rifiHed laundci's and an niidcrcurrent. At the Washington dump about }^ mile below, they were sluicing through rittled launders and an undercurrent to an Eccleston slime concentrator. The deck of this table was covered with a rubber plate having fine, molded rifllcs. Tt was driven by a '_' h. j). Aerniotor gas engine, and wa.s producing, per 8-hour da.w tiOO Ih. of mitldlings yield- ing 2% mercury and 50 lb. of concentrates yiekling np to 60% mer- cury. These products after drying wei-e retoT'ted with sorted ore from the mine. As at Oat llill. it was impi'actieable to determine the per- centage of extraction made by the concentrators, because the material '•Bradley, W. AV., Mines & mineral res. of t'olu.sa, et al. counties: Cal. State Min. Bur., chapters of St;ite JMIiicialogist's Fteport, litl3-l!"14, p. 67, I'.HS; also in Report XIV, p. fMK l!ti(;. '-0/*. cit., pp. Ill 114 : al.so in Report XI\', pp. 283-2S6. QUICKSILVER RESOURCES. 337 was ground-sluiced from the dumps, makino; difficult even a reasonable estimation of the weights handled. Only the weights of concentrates and resulting quicksilver, and its final cost per flask produced were readily determinal)le. Even this was usually not recorded. R. P. Newcomb at the Oat Hill mine figured that he could produce quick- silver there at a cost of $10 per flask ; but his was an unusually favor- able case. Since the rehabilitation and resumed operation of the 60-ton Scott furnace at the ^Etna mine, the past year [1917], concentration has been discontinued by the present operators. Among some other, smaller operators in the Colusa-Lake-Napa- Sonoma district, who have been concentrating quicksilver ores during the past two years, the following are noted: At the Twin Peaks mine, near the Oat Hill mine, Napa County, for a time in 1916, material from the dumps was concentrated on one New Standard table. At the Great Western mine, Lake County, the Royal Development 'Co. operated for a time in 1916 on dump material with one New Stand- ard table, since removed to the Big Injun mine west of Middletown. At the Great Eastern mine, Sonoma County, concentration was tried for a short time with a Gates machine in 1916, but only the coarser sulphide was recovered, the slimed cinnabar remaining in suspension and lost with the tailings. The ore was apparently ground too fine. At the Big Injun mine. Lake County, there is one New Standard table (formerly at the Great Western mine), which was employed on low-grade ore during the winter of 1916-1917 while the water supply was sufficient. The addition of a revolving screen has since been made to the equipment. The ore contains native quicksilver as well as cin- nabar, in soft serpentine. The concentrates are retorted with high grade ore. A few flasks of quicksilver, each, were made in 1916, utilizing con- centration, at the Wilbur Hill mine, Colusa County, adjoining the Manzanita: at the Baker mine. Lake County; by 0. W. Boeseke in Los Priestos district, Santa Barbara County; and at the Rattlesnake mine, Sonoma County, the ore of this last-named mine carrying largely native quicksilver. At the Bella Union mine, Napa County, in 1916, a Deister table was tried by the Rutherford IMining Co., but it saved only the coarser cin- nabar. Then a K & K flotation machine was installed, the fine grind- ing being done with a Hendy ball mill, 3' diam. x 3' long. Flotation is stated to have saved the slimed cinnabar from the pulp, well; but the ide of the washing plant. At the Guadalupe niin(\ Santa Clara County, a concentrating plant of 50 tons daily capacity was built in the winter of 1916-1917. and "See Photo No. 50, ante. *Pince the above was written, owins to the material becoming lowe'r grade, a small hydraulic giant sluices it to a sump, whence it is raised by a centrifugal pump to the launders. 346 CALIFORNIA STATE MINING BUREAU. st.irlcd oix'i-atiiiii- in Fchriuiry on material from the old mine dumps. The mill is on the hank of the creek, alongside of the dumps. The ore is trammed hy hand and dumped into an underground pocket from which it is hoisted by a .ski|) to the mill bin. Crushing is done in a -V X 4' Ilendy ])all-mill, with 20-mesh screen discharge, from Avhieh the pulp passes through a Dorr Simplex classifier. The coarse product goes to 2 Wilfley sand tables, and the fines to a #5 Deister and a Deister-Overstrom table. The concentrates are stated to assay 8^-10% mercury as only a roughing operation is attempted. Con- siderable slimes are made. The concentrates are reduced in the fine- ore furnac(\s. At the Harrison mine, Yolo County, undei' l)ond to January Jones, a concentration mill was being built in July, 1917, when visited by IMr. Emile Huguenin of the staff of the State Mining Bureau ; and from whose notes the following data are taken. The mill is to have a capacity of 150 tons of ore daily; and is equipped with crushers, ball-mill, Wilfiey tables for the sand, and Deister concentrators for the slime. It is expected to begin operation of the mill after the fall rains provide a water supply. Meanwhile, ore from the mine was being hand-sorted and retorted. At the Sulphur Bank mine, under bond to the Sulphur Bank x\sso- ciation, ])reparations are being made to concentrate the extensive dumps (tf many years' accumulation. Practically all of the dumps in sight (see Photo No. 10, ante), and some over the hill on the north side have concentratable values. A steam-shovel will be utilized for excavating the material, and motor-trucks for transportation to the mill bins, as it will be necessary to haul it up to one-third of a mile in distance and raise to an elevation above the mill-site. When visited by the writer in September, 1017. a plant serving as a test unit had been in operation several weeks. The main difficulties encountered here, not only in concentrating, but in assaying, retorting or fui-nac- ing, are all due to the excess of free sulphur. A sami)le of concen- trates assaying 15% mercury, show(Ml on analysis a content of over 20%- native, free sulphur. Table tailings from the same run showed 15% free sulphur. No provision had as yet been made in this test- unit for crushing or grinding the feed. Of 500 tons excavated, daily, 300 tons of the coarser material was eliminated by the grizzly: and the revolving screen (i inch opening) took out 75 Ions from the remainder, leaving 125 tons daily to he handled l)y I he 4 Deister-Overstrom tables. There were two Challenge ore feeders below the ore-bin chutes. The revolving sei-een was l(i' long x 42" diaiti.. made of single-crimped wire, the whole plant being driven In' a 15 h. ]). gas engine. Water is puniped against 85' head, from Clear Lake to two wooden tanks (.^LICKSllAEK KESOURCES. 347 (6,000 and 10,000 gal.) above the mill, l)y a tfiplex, geared Gould pump, lOO-gal. per min., driven by a 10 h. p. Type Y, Fairbanks- ]\rorse, semi-Diesel engine burning 24° R. fut^l oil. Another, 200-gaL pump will later be added. As the tables were at first operated on this ore, the concentrates and middlings were rather crowded together, and considerable native sul- phur was mixed with both. Though a cleaner concentrate was obtained than later, it was at the expense of extraction, as cinnabar in tlie middlings was crowded over into the tailings. B,y flattening the grade of the table and changing the wash-water feed, the products were spread out more, and showed the following order at the concen- trate end : a bright red streak of cinnabar ; a bright-yellow streak of fairly clean native sulphur ; a mixed streak of sulphur, cinnabar and some middlings ; middlings, containing in addition to some cinnabar and sulphur, the coarser particles of the white leached basalt. Finer crushing will probably eliminate the last-named. It is expected that later another table may be added to clean the middlings and to make a fairly clean sulphur product. The assays given herewith, show the improvement in extraction with the change of practice, and the relative changes in assay values of the products. The percentage of extraction is calculated on the basis of the following equation : 100 b (a-c), Recoverv = where a = head assav ; b = concentrate a (b-c) a.ssay; c = tailings assay. This gives a slightly higher result than the 'indicated extraction' based on the simple proportion of tails assa.v : heads assav, subtracted from 100. Date 8/23/17 8/23/17 8/23/17 8/23/17 8/24/17 8/24/17 8/24/17 9/ 1/17 9/ 1/17 9/ 1/17 Sample Mill heads Tailings Concentrates (forenoon) Concentrates (afternoon) Heads Tailings Concentrates Heads Tailings Concentrates Per cent Hg. 2.44 1.44 25.1 28.0 2-5 1..52 24.5 2.04 0.40 14.8 Pounds Hg. per ton 48.8 28.8 502.0 560.0 50.0 30.4 490.0 40.8 8.0 296.0 Per cent recovery 43.4 42.6 82.6 Screen analyses show most of the mercury lost in the tailings to be in the fines. For the present, the concentrates iirc being retorted, along with debris from the old Scott furnaces and coiidcnsers. The concentrates are spread out on a concrete floor to dry. after which lime is added in the proportion of 1 lb. to eaeli i)ound (it) <>f free sulphur 348 CALIFORNIA STATE MINING BUREAU. contained. The large amount of sulphur present has a strong aiSnity for the iron of the retorts ; and various expedients have been tried for overcoming it. With a larger plant in operation after the present test-unit has served its i)urpose, some other form of furnace will no doubt be used, as retorts are of too limited capacity, and the labor eost-per-ton for operating Wunn is high. QUICKSILVER RESOURCES. 3-1:9 ESTIMATES OF CONCENTRATION COSTS. To say with any detiuitenoss beforehand what a given process will cost is not a simple matter. Costs vary widely with equipment, char- acter of ore, labor, and other local conditions. So few mines that have tried concentration on quicksilver ores have kept an accurate or any account of expenditures, that it is diiScult to give any exact fig- ures. From a comparison of cost data on mills handling other ores, it is reasonable to estimate that, with average conditions obtaining in the California quicksilver districts, table concentration can be con- ducted at cost figures between 50^ and $1.25 per ton, including crush- ing and table operations, labor, supplies and repairs. Richards^ gives actual concentration costs in certain stamp-mills of : $1.00 per ton with a 95-ton per day mill; $0.92 per ton on a 175-ton capacity; and $0.28 on a 700-ton daily capacity. Rolls will do better work on quick- silver ores, and probably be cheaper than stamps. Water required will amount to from 5-8 tons (1200 to 1900 gal.) per ton of ore, depending largely on the nature of the ore. "With concentration by flotation, operating costs will be somewhat higher on account of the cost of finer grinding. From the experience at New Almaden- it would appear evident that, where sliming is necessary to release the cinnabar, such treatment can not compete with the Scott furnace ; even though it yield a somewhat higher recovery. Cost data have been published in a number of recent instances for flotation plants. Simons"' gives the following for the Timber Butte mill, Montana, treating 450 tons daily of a complex copper-lead-zinc- pyrite ore and making several products: "Treatment costs have averaged between $2 and $2.25 per ton of ore passed through the miU. This covers labor, power, water. supDlies, repairs, and general expenses, but not interest on investment and depreciation." In the mill of the Consolidated Arizona Smelting Co.,* at Humboldt, Arizona, treating 240 tons per day, of copper ore: "The total cost of concentration, including coarse crushing and flotation royalty, is slightly over $1 per ton. In September [1915] it was .$1.03. Exclusive of royalty, the cost of the flotation part of the treatment has been STc* per ton during a period of six months. The cost for oil is 2.S<^ per pound on a consumption of a little less than one pound of oil per ton of crude ore. The power consumed by the flotation machine [Minerals Separation] is 32.7 kw. per 24 hours." 'Richards, R. H. : Ore Dressing, vol. II, pp. 1129, 1133; 1905. =See p. 243, ante. ^Simons, Theodore, The concentrator of the Timber Butte Milling Co., Butte, Mont. : Am. Inst. Min. Eng., Bull. Sept. 1915, p. 1307. ^Unsigned, dotation at Humboldt, Arizona: Min. & Sci. Press, vol. 112, p. 41, Jan. S, 191B. "Precis of an article appearing in Metall. & Chem. Eng., Dec. 1, 1915." 350 CALIFORNIA STATE MINING BUREAU. At Copperopolis, California, on copper ore, using Callow cells, Kob- bins^ gives the following data: "Operating costs. These are shown by the following figures taken at random from the company's books, representing actual costs for the week ending July 7, 1916: "Power, 184 h.p. per day, at O.Si'oC per kw. hr $191 25 Operating labor, 70 shifts, at $3.25 228 75 Superintt-ndence, repair and extra labor 137 48 Supplies of all kinds 132 40 $689 88 "On a normal tonnage of 192 per day, this is equivalent to 51. 4(' per ton." REDUCTION OF CONCENTRATES. The concentrates being obtained, have yet to be roasted to get the final, desired product, — metallic quicksilver. Retorts are of limited capac- ity, but if used, the concentrates are likely to require some stirring to prevent packing on account of their high specific gravity, especially if assaying between 10% and 40% mercury. At higher values than 40%, the sulphide should be self-burning and leave but little residue. However, it is rarely ever economic to produce such a high-grade con- centrate. A small furnace of the Scott type could be used, with a narrower shaft and narrow shelf -slit : such as was in use for treating soot at the New Idria mine for some years until the recent installation of the soot concentration mill. This was suggested by the writer*^ in a recent report on the quicksilver mines of Lake County. Here again we have the fuel combustion products mixed with the quicksilver vapor, and the attendant condensing difficulties. Some form of a rotary roaster may be adapted, similar to the concentrate drier now in use at New Idria ; or a small-size unit of the Wedge muffle-fired type of mechanically-rabbled furnace. This last-named would have the advantage of the retort principle of keeping the quicksilver vapors apart from the products of fuel combustion. The Landers retort^ would also have this same advantage, but in view of recent experience at Sulphur Bank, it is doubtful if any form of cast-iron retort would last long when handling concentrates, on account of the sulphur matteing with the iron. ■'■Robbins, H. R., Flotation at the Calaveras Copper — a simple flow-sheet : Min. & Kcl. Press, vol. 113, p. 772, Nov. 25, 1916. "Bradley, W. W., Mines and mineral resources of Colusa et al. counties, chapters Of State Mineralogist's report, 1913-1914, Cal. State Min. Bur. p. 56, 1915; also in Report XTV, p. 22 8, 1916. 'See D. 218. ante. QUICKSILVER RESOURCES. 351 ADVANTAGES OF THE ALKALINE SULPHIDE SOLUTION METHOD. The most striking- and attractive advantage of this method is that it obviates the necessity for an expensive furnace instaUation, on those ores which are amenable to it. With the exception of heavily ochreons ores, practically all quicksilver ores can be handled by it. In some cases where extreme tine-grinding- would be required to give the solution contact with the mercury minerals, the cost will doubt- less be too high in comparison with Scott furnace treatment. For most ores, grinding need not be tiner than — 80 or — 100 mesh. The plant installation should not cost over one-half that of a Scott plant, as the standard cyaniding equipment (but without agitators) can be utilized. This can be done for under .$500 per ton-day capacity. With this system, it is not necessary to wait months or even weeks after installation before metal can be put on the market. Such a plant is quicker to install than furnaces, and once in operation, clean quicksilver is ready for bottling in 3 or 1 days at the outside. The time of contact required of the ore and solution is very short. By grinding 'in solution', the solvent Avill have done its work by the time the pulp reaches the filters, without the necessity of any intermediate agitators. The possible recovery is high, approaching 100% of the metallic content of the ore. This last-named item will offset the some- what higher operating cost as compared with furnace practice. ;5r>2 CALIF'ORNIA STATK MININC BrHEAU. CONCLUSIONS. With some of the conclusions suiiiiiKirizcd in a recent paper by Landers.^ the autlior is. in the iiiiiiii, in accord: "Extractions as high as Se^/f have been obtained by crushing and tabling the ore, but there are undouljtedly some ores in which the cinnabar occurs in an almost amorphous state, wliorc tlu^ exti'action by tabling alone can not be brought much above fiO to 70%. Careful tests have indicated tliat tlie losses here occur almost entirely in the fines that are apparently in suspension in the pidp and as dotation results have shown that, so far as cinnabar is concerned, it c'an be successfully applied only to the fines, no doubt a total extraction of over 90% can in most cases be economically obtained. Other sulphides, notably pyrite, are almost always present in cinnabar ores, and tliis pyrite can be concenti'ated out with the cinnabar, proving a valuable addition to the succeeding furnace operation and cutting down the amount of fuel necessary to smelt the ore. Concenti'ation has one other great advantage, which is that it elimates the asphaltvun products and other carbonaceous materials that are nearly always found in the ores and are among the chief sources of difficulty in the proper collection of the mercury after smelting. It might be well to mention here that all fli'e methods of reducing cinnabar call for subseciuent condensation of the mercury \apors and that any hydroc;irbon distillates that may be condensed with the vapors add greatly to the difficulty of collecting the metallic mercury. "Briefly, such concentrators as have been installed recently consist of rock crusliers, ball mills and various types of tables. Jigs have been tried in one place and no doubt should be given a more general trial elsewhere. The coarser the con- centrate that can be made, the more favorable it is for roasting in the furnace, and if retorts are excepted, none of the present furnaces would work very long on typical flotation concentrates. * il: i,i 4; * * * "A thorough knowledge of the losses, mechanical and metallurgical conditions leads one to forecast that the future will either bring out a successful wet method for leducing mercui'ial ores or will develop the wet concentration of these ores until a saving in excess of 9 0% will be made on a commercial scale. Furnacing of the ores will probably always be the cheapest in per ton costs on tonnages greater than 2.5 per day and on ores in excess of 1% mercury content. The losses sustained in treating low-grade ores in furnaces will in all probability be greater than that of wet concentration plus a proper retorting of the concentrates. "Mines Iiaving large investments in furnace plants will continue to use them up to capacity, but will build concentrating plants for their lowest-grade ores, mixing the resulting concentrates with the ore going to the furnace. The low per-ton cost of a concentrating plant together with its necessary retorts will probably preclude the erection of more large furnaces, although in the case of the installation of a large concentrator the quantity of concentrates oljtained will necessitate the construction of some type of furnace with greater capacity than can be secured from retorts. This will bring in mechanical furnaces having little or no application of external heat, the concentrates containing sufficient sulphui- to provide their own fuel. Such a condition would be ideal for the distillation of mercury, as the volume of furnace gases with attendant vapor loss could be kept down to a minimum. The price of mercury may influence the choice of process." The ultimate decision between a straight furnace reduction, or con- centration and roasting of concentrates will be a matter of compar- ative costs coupled with comparative extractions. The initial install- ation of a Scott fine-ore furnace unit is high (including condensers, etc., $1000 per ton-day capacity. We know of instances where the cost has been materially less than this figure, but they are the excep- tion rather than the rule) ; the extraction is ordinarily low (in the majority of cases probably not over 75%) ; the cost of operation is low (50^ to 75^- per ton for large units, economically managed, though this does not include high-cost repairs, interest or depreciation on the high initial installation capital). A table concentration plant of equal capacity will require approximately one-fifth the initial capital expenditure, and a correspondingly lower depreciation charge; prop- erly designed and operated, it should give 25% to llO^f higher extrac- 'Landers, AV. IT.. The smelting of quicksilver ores: Eng. & Min. .lour., vol. 102, pp. 630-6."?.*?, Oct. 7, i;>16. QUICKSILVER RESOURCES. 353 tion ; but the operating cost, on account of finer crusliing, will be 30% to 50% higher. An alkaline-solution plant will require less than one- half the initial capital expenditure of a furnace plant and yield prac- tically a complete extraction. These points will have to be determined upon for each individual property. In this connection, while calling attention to the subject of capital expenditure, it is apropros to state that the items of amortization, depreciation and interest are too often omitted from consideration in cost data. Their inclusion is vital in a consideration of the proper plant and treatment for a quicksilver ore. The writer is of the opinion that either concentration or the alkaline sulphide solution method can be economically adopted at some quick- silver properties, depending on the nature of the ore and gangue asso- ciations; but it does not appear that they are likely to any consider- able extent to displace the Scott furnace. Concentration may also serve as an adjunct to some existing furnace plants, to increase their capacity, as is at present being done at New Idria. 23—38540 354 CALIFORNIA STATE MINING BUREAU. PART III. BIBLIOGRAPHY ON QUICKSILVER. Pai-t A: re assays, chemistry, ore-dressing, metallurgy, etc. Inolucl- ing some references relative to ore-clressing of other niet^ils. because of their value for comparative purposes. Aeegg's Handbuth der Anorganisclien Chemie, vol. II, Pt. 2, p. 632, 1908. re solution by Na„S. Adams. W. J., Floiirins-Quicksilver in pan amalgamation. An explanation of the causes of the flouring- of quicksilver. Serial, 1st part, 900 w. Min. & Sei. Press, Nov. 5. 1904. Agricola, Georgius, De natura fossilium, 1546. liber VIII. De re metallica, first Latin edition of 1556, translated by H. C. Hoover & L. H. Hoover, 1912, pp. 2, 110, 247 (re assays), 426-432 (re furnaces and distilla- tion methods; illustrated). Allen, E. T. & Crenshaw, J. L., The sulphides of zinc, cadmium, and mercury ; their crystalline forms and genetic conditions; Am. Jour. Sci., vol. 34, pp. 341-396, Oct., 1912. Give details of laboratory research work on these sulphides. Baker, A. L., in Chem. News, vol. 42, p. 196. 1880, re preparation of mercury antimonial sulphide. Ball, L. C, Mercury in Queensland: Queensland Gov. Min. Jour., Dec. 15, 1914; re occurrence and treatment. Maps. 6000 w. Barfoed, C. T., re behavior of mercuric sulphide to sodium sulpliide ; Jour, prakt. Chemie, vol. 93, 1S64, p. 230. Baverstock, R. S., Quicksilver : Min. and Sci. Press, vol. 84, 1902, p. 4. Contains general notes on tlie occurrence and treatment of quicksilver ores, with descrip- tions of California deposits. Becker, G. F., On the solution and precipitation of cinnabar and other ores: a digest of Chapter XV of U. S. G. S., Mon. XIII, which appeared in Am. Jour. Sci., 3d series, vol. 33, p. 199, 1887. Geology of the quicksilver deposits of the Pacific Slope : 'Slon. U. S. Geol. Survey, vol. 13, 1888; Abstracts, Am. Geology, vol. 5. pp. 17 8-180 ; Am. Naturalist, vol. 24, pp. 850-851 ; Am. Jour. Sci., 3d ser. vol. 39, pp. 68-69 ; Eng. and Min. Jour., vol. 49, pp. 137-138. , Quicksilver ore deposits: U. S. Geol. Surv., Min. Re.s. of U. S. for 1892, pp. 136-162, 1893. in Am. Jour. Sci.. vol. 31, p. 120, 1886; re formation of cinnabar and mettacin- nabarite from solutions. Bertheldt, Introduction a 1 etude de la chimie ancienne, 1889, p. 4 et passim, re ancients' knowledge of amalgams and fire-gilding. Binder, G. A., in Min. pet. Mitt., vol. 12, p. 332, 1892. Re solubility of cinnabar in distilled water. Black's Supreme Court Reporter, vol. 2 : The United States vs. Andreas Castillero, before the Supreme Court, December term, 1862. The testimony gives history of quicksilver discovery and early development in California, with particular refer- ence to New Almaden. Booth. F. J., The reduction of quicksilver ore: Min. and Sci. Press, Nov. 10, 1906. Boutwell, J. M. Quicksilver: Mineral Resources U. S. for 1906, U. S. Geol. Survey, 1907, pp. 491-49!t. Bradley, Walter W. Quicksilver reduction at New Almaden, Cal. : Min. & Sci. Press, vol. 87, p. 201, Sept. 26. 1903. Short description of furnace practice. • Mines and mineral resoiu'ces of the comities of Colusa. Glenn. I.iake, Marin, Napa, Solano, Sononi.a, Yolo; chapters of .State Mineialogist's report, biennial period, 1913-1914, .July, 1915. Includes descriptions of quicksilver mines and metallurgical pr.actice. These sections, also F'resno, Madera, Kings counties, included in Report XIV, 1916. et al. authors — Mines and mineral resources of the counties of ^Monterey, San Benito, San Lviis Obispo, Santa Barbara, Ventura: chapters of State Mineral- ogist's report, biennial period 1915-1916, Dec. 1916. Includes descriptions of quicksilver mines and metallurgical practice. These sections included in Report XV, 1917, (in i)ress). Brand, Dammer. Chem. Technologie, vol. II, p. 41. Re electrolyis of cinnabar. Brelich, Henry. Chinese methods of mining quicksilver. Describes the methods in the Wan Shen Chang mines, showing how they make a living by mining low grade ore in the most anliiiualed way, and .smelling it with the most primitive appliances. Ills. Serial, 1st part, 2500 w. Min. Jour. May 2 7, 1905. Also in Trans. Inst. Min. & Mel., vol. XIV, pp. 483-496, 1905. Native methods of mining and smelting quicksilver ore in Kweichow, China. Notes relating to tlie wages, prices, e.xcliange, coinage, laws, and customs used by the natives in (luicksilver mining. 4 800 w. Cassier's Mag. Jime, 1907. Brown, C. F., Oil-buining mercury retort furnace and condenser: Min. Reporter, April 18, 1907. Brunner, C, re the double soluble salt HgS.ICS -f 5H..O : PoggendoriT, Annahn, vol. 15, p. 593 (1829), QUICKSILVER RESOURCES. 355 California State J^Iining Bureau, Report of State Mineralogist, vol. I\". p. 332, 1884. re quitksilver assay. vol. Vni, pp. 541-542, 1888. Re New Almaden furnaces. vol.X, pp. ;t20-!i29, ISnO. Reprint of article l).v J. B. Randul in lllli Census Report, re statistics, wages, etc., in quicksilver plants. vol. XII. pp. 35S-372, 1884. Describes mines and reduction eciuijiments. vol. XITI, pp. 594-604. 1896. Describes mines and reduction equipments. vol. XIV, pp. 176, 189-191, 202, 203, 226-240, 283-292, 311-312, 342-351, 369, 456-464. 528-530, 923-924. 1916. Describes mines and reduction equipments. Bulletin 27 — Quicksilver resources of California, by Wni. Forstner, 1903. Describes mines, geology, metallurgy. IIlus. Carey, El.mer E. Principles of electrolytic amalgamation : Min. World, vol. 32, 1910, pp. 896-897, U p. Castek, Fraxz, Die Bestimniun.g und Verminderung der Verluste beim Queoksilber hiittenwesen. (The determination and reduction of losses in quicksilver furnace practice) : Berg- und Hiittenmannisches Jahrbuch (Loebner Jahrbuch), LiV'IlI Band, Wien, 1910. Describes practice at Idria, Austria. Chism, Richard E. A new assay for mercury. Shows the uncertainty of some methods, the drawbacks of the gold method, and describes the use of silver for receiving the mercury. 2500 w. Am. Inst, of M. E., Oct. 1898. Christy. S. B., Quicksilver reduction at New Almaden, Trans. Am. Inst. Min. Eng., XIII, pp. 547-5S4, 18S4. Describes ores and furnaces, and furnace practice. ■ Quicksilver condensation at New Almaden, Trans. Am. Inst. Min. Eng. XIV, 206-264, 1SS5. Describes condensers and practice; also details experiments and analyses made. On the genesis of cinnabar deposits: Am. Jour. Sci. 3d ser., vol. 17, 1879, pp. 453-4 63. • Mineral Resources U. S. for 1SS3 and 1884, U. S. Geol. Surv, 18 85, pp. 503-534. Contains quicksilver reduction at New Almaden. The Imperial quicksilver works at Idria, Krain. Translation of a report by M. A'. Lipoid, et al.. issued bv the management in celebration of the 300th anni- versary. Publ. by J. B. Randol, 1884. The mines and practices at Almaden, Spain. Translation of a paper by M. Kuss. in Annales des Mines, 1878. PubL by Dewey & Co., San Francisco, 1879. Clarke, F. W.. Data of Geochemistry: LT. S. G. S., Bull. 616, pp. 664-669, 1916. Collins, H. F., Quicksilver mining in the district of Guadalcazar, San Luis PotosI, Mexico. Trans. Inst. Min. & Met., vol. IV, pp. 121-15 0, 156, 1895. Also gives metallurgical data. Crookes & RoHRiG, Practical treatise on metallurgy, 1868, pp. 504-531. Contains section on mercury. De Kalb, Courtenay. Guadalupe quicksilver works: Min. and Sci. Press, vol. 100, 1910. pp. 446-447, 2 p. Dexnis, Clifford G., :Modern quicksilver reduction: Min. and Sci. Press, vol. 99, 1909, p. 761. Dennis. "V\'illiam B.. Shoi-tening the roasting period for mercury ores: Eng. and Mm. Jour., vol. 88. 1909, p. 112. DE RivERO, M. M., Memoria sobre el rico mineral de azogue de Huancavelica; Lima, 1848. ,,. „^ ,^ DiNSMORE, Charles A. Quicksilver deposits of Brewster County, Tex. : Mm. U orld, vol. 31, pp. 877-878, 6 figs., Oct. 30, 1909. Includes description of plants. DiTTE, A., in Compt. Rend., vol. 98, 1884, pp. 1271, 1380. re transformation of vermilion to crystalline cinnabar. . DOELTER, C, in Zeitschr, Kryst. Min., vol. 11, p. 33, 1S86. re formation of cinnabar bv action of HoS on mercury. DuscHAK, L. H.. & SCHUETTE, C. N., Condensing quicksilver from furnace gases: Mm. & Sci. Press, vol. 117. pp. 315-323, Sept. 7, 191S. Eddy, L. H., Jigs on a California dredge: Eng. & Mm. Jour., vol. 101, pp. 20i-208, Jan. 29, 1916. Describes use of Neill jig on gold dredges. Egleston, T., Metallurgy of silver, gold and mercury in the United States, vol. 11, 1890; re mercury, pp. 799-801; re concentration pp, 804, 806. Detailed descrip- tions of furnaces. , .,. ,^ _ „_ „„„ The method of collecting flue-dust at Ems, Trans. A. I. M. E. XI 3(9. , Treatment of mercury in North California. Reprinted from Engineering, London, 1880. 24 pages and 2 plates. , iao Eng. & MiN. Jour; Oceanic quicksilver mill: Editorial Correspondence, vol. 10-, p 512 Sept. 16. 1916. Describes concentration mill, also wooden condensers. EscosuRA, L. de la & de Botella, F. Histoire de la Metallurgie du Mercure en Espagne, 1878. Abstracted in "Annales des Mines," 7 Serie, t. 15, p. 524, 18(9, by M. K.u_ss, EscosuRA, L. de la, in Historia del Tratamiento Metalurglco del Azogue en Espana, jMadrid, 1878. F.AWCETT, W., A quicksilver furnace: Am. Inventor, November. 190d. ^ Feust, Arthur. Modern quicksilver reduction: Min. and Sci. Press, vol. 99, p. /9o. Flotation Process, The, compiled and edited by T. A. Richard ; publ. Mm. & Sci. Press, 1916. Contains articles theoretical and practical on many phases of flotation, by various authors. ■ ^ ^ Forstner, William. The quicksilver resources of California: California State Mm Bur., Bull. No. 27, 1903. Reprinted, 1908. Includes chapters on metallurgy of quicksilver, geologj- of quicksilver belt in State, genesis of quicksilver ore deposits, mines. FouQufi & Levy : Synthese des mineraux et des roches, p. 313. FuRMAN's Manual of Practical As.saying. 1893, p. 133, gives mercury as.says Gandolfi, Les mines et usines d'Almaden : Ren. Univ. des Mines et de la Metall., 1889. Describes practices at Almaden, Spain. . Geary, J. W.. A rotary furnace for roasting quicksilver ores: Mm. and Sci. Press, Jan. 14, 1905. Condensation of quicksilver vapors: California Jour. Tech., 190a; also Mm. Reporter, Apr. 19, 1906. 356 CALIFORNIA STATE MINING BUREAU. Gmei.in-Kraut, re alkalint' and mi'icniic sulphides: Handbuch der Clieinie, Anorgan- ische Chemie, vol. :i, p. 756. GOODALE, C. W.. and Klepin'ger. J. U.. The Great Falls flue system and chimney : Trans. Am. Inst. Min. Ens., vol. 16, p. 583, 1913. Describes experiments on flue system.s, some items of which have an interesting bearing on quicksilver condenser problems. Goodyear, "W. A., report on an examination of the quiek.silvcr mines of Califoi-nia (May, 1871) : Geol. Surv. of Cal. (Whitney), Geology vol. II. Appendix, pp. 91-135, 1882*. Describes mines, geology, and furnace practices. Illiis. Griffiths, Andre P. The Ohaeawai quicksilver deposits (N. Z.). Read before the N. Z. Inst, of Min. Eng. Results of prospecting and mining operations, giving localitv geological features, deposits, their origin and formation and describing the furnaces. 4400 w. N. Z. Mines Record, Mar. 16, 1S99. GuiLETT, M. L., in Revista Minera y Metallurgica, vol. 63, pp. 101, 143, et al. 1912. Descrilies general furnace practice ; and gives temperatures in the Cermak-Spirek furnace. Halse. Edward. The quicksilver mine and reduction works at Huitzuco, Guerrero, Mexico: Trans. North of Eng. Inst, of Min. and Mech. Eng., vol. 45, pt. 1, 1.S95, pp. 72-SS. Describes the geologic features of tlie region, the character and occurrence of the ore, and discusses its origin. Hamilton, E. M., Flotation for cinnabar, Min. & feci. Press, p. 541, Apr. 15, 1916, under "Discussion." Hanks, H. G., Cal. State Min. Bur., Report IV, pp. 332, et al., re quicksilver, assay and metallurgy. Heberlein, C. a.. The mining and reduction of quicksilver ore at the Oceanic Mine, Cambria, Cal., Bull. Am. Inst. Min. Eng., Feb., 1915. pp. 497-504; also Trans. vol. LI, pp. 110-119. lUus. Helmacher, R., The quicksilver reduction works at Idria, Austria: Min. Ind., vol. IV, pp. 531-538, 1895. Includes also a short description of the dry ore-dressing methods practiced. Hilleerand. W. F. & Schaller, AV. T., U. S. G. S. Bull. 405, p. 37. re methods of analvsis for Hg. Hoover, H. C. and L. H., translation of Agricola's de re metaUica. 1556, pp. 2, 110, 247, 354. 426-432, 1912. Illus. Idria, Austria mines : Die K. K. Quecksilberwerk zu Idria in Krain. Translated by S. B. Christv. 1884, publ. by J. B. Randol, San Francisco. Innes. Murray, California quicksilver: Eng. & Min. Jour., vol. 101. p. 6S, Jan 8, 1916. Discusses metallurgy, also economic conditions. Ippen, J. A., in Min. pet. Mitt., vol. 14, p. 114, 1894. Re transformation of black to red sulphide of mercury. James, George A., The James apparatus for quicksilver determination: Eng. and Min. Jour., vol. 90, 1910. p. SOO; also Min. & Sci. Press, vol. 93, p. 606, Nov. 17, 1906. Janin, Louis, Jr., Mining and metallurgy of quicksilver in California : Report for 1873 on mineral resources of the States and Territories west of the Rocky Mountains, bv R. W. Raymond, special commissioner, Washington, 1874, pp. 379-407. Janda. Y.. Rohstupp vom Schuttofen Nr. IIL der k. k. Quecksilberhatte in Idria. (re soot formation in a fine-ore furnace at Idria, Austria) — Oesterreichische Zeitschrift fur Berg- und. Hiittenwesen, vol. 157, pp. 637 et seq., Oct. 16, 1909. JORY, J. H., New method of quicksilver extraction. Describes the method and states its advantages. The most essential part of the new method is the electrolytic sluice. 1500 w. Min. & Sci. Press. Dec. 28, 1901. Kerl, B., Muspratt's Chemie. Art. Quicksilver. Contains description of manufacture of vermilion in the dry way by the ancients. KiRCHHOFF. G. S. C, in Allg. Jour, der Chemie, Scherer, vol. 2, p. 290, 1799 (?). re preparation of vermilion in the wet way. Knox, J., in Trans. Faraday Soc, vol. 4, p. 29, 1908, re alkaline sulphide mercury salts. KONINCK, L. L. de, in Annales Soc. geol. P.elgicjue, vol. IS, p. XXV, 1891. re solubility of mercuric sulphide in alkaline sulphide solutions. Kuss, M. H., "Sur les Mines et Usines d' Almaden," in Annales des Mines, 1878, 7 Serie Men. t. 13, pp. 39, et al. Translated by S. B. Christy, publ. by Dewey & Co., San Francisco, 1879. Landers. W. H., Quicksilver mining in California, Min. & Sci. Press, vol. 112, pp. 282-284, Feb. 19, 1916. Discusses lack of advancement in metallurgy of mercury ; describes furnace practices and products. The .smelting of mercury ores: Eng. & Min. Jour., vol. 102, pp. 630-633, Oct. 7, 1916. Discus.scs metallurgy, losses, sampling products, and concentrates. Lang. Herbert, Quicksilver reduction. Min. & Sci. Press, pp. 707-714, May 13, 1916. Discusses ores, assays, concentration, etc., in much detail. Lewis, R. S., The dispo.sal of flotation products: Min. & Sci. Press, vol. 114, pp. 473-484, Apr. 7, 1917. Describes the handling of various flotation products in practice at a number of plants in the western U^nited States. Liebenow, C. The constitution of mercury (Ueber die Konstitution des Quecksilbers). A paper before the Electrochemical Society .showing mercury to be composed of molecules of different atomic constitution. 3500 w. Zeitschr. f. Elektrochemie- May 20, 1898. _ , .. , LiPOLD, M. v., et al.. The Imperial quicksilver works at Idria, Ivram. Translation by S. B. Christy of a report issued by the management in celebration of the 300th anniversary. Pul»l. bv J. B. Randol, 1884. Low, A. H., Technical Methods of Ore Analysis. 1905, pp. 156-158. Lunge, G.. & Keane, C. A., Technical Melliods of Chemical Analysis, vol II, pt. I, pp. 152-153. Mactear. James, Mining and metallurgy of quicksilver in Mexico. Trans. Inst. Min. & Met., vol. IV, pp. 69-120, 1895, re metallurgj', pp. 102-120. QUICKSILVER RESOURCES. 357 McDermott, ^VALTKR. Notes on the concentration of finely crushed ores: Min. Ind., vol. IX, p. 778, 1901. Mention.s cinnabar in a list of sulphides which seem adapted to treatment by the Klmore pioccss. MfiHU, M. C., re tlie soluble, crystalline mercury-sodium sulphide : Russian Jour, of Pharm., reported in Jahresbericlit der Cliemie, 1876, ji. 282. Mineral Indstry, re practice at Monte Amiata, Italy: vol. VI, pp. 568-.'jS2, 1898; VII, p. 580, 1899; vol. VIII, pp. 493-494, 1900: vol. IX, p. 567, 1901; vol. X, pp. 559-561, 1902. Treatment of quicksilver ores in the Asturias, Spain. Vol. IV. Describes, with illustrations, the several types of furnaces employed and the method of operating each. 3000 W. Eng. & Min. .Jour., Aug. 15. 1896. Mining and Engineering Review, Metallurgy of ciuicksilver, Aug. 30, 1905. Mining and Scientific Press, Tlie use and care of mercur.v. Aug. 17, 1907. 2500 w. Explains some of the causes of the llouring and sickening of ciuicksilver and various methods of remedying the evil. Western American Metallurgy, vol. 114, pp. 303-307, Mar. 3, 1917. Discusses ore-dressing and metallurgical methods, some of whicli may have application to quicksilver. The paragraphs on primary and secondary grinding (pp. 304, 305) are of especial interest. , re flotation of cinnabar. Editorial, vol. 109, p. 585, Oct. 17, 1914. , Flotation at Humboldt, Arizona: vol. 112, p. 41, Jan. 8, 1916. Gives cost data. Precis of an article appearing in Metall. & Chem. Eng., Dec. 1, 1915. , re flotation oils, vol. 112, pp. 869-870, June 10, 1916; also, pp. 598-601, Apr. 22. 1916. re quicksilver market, vol. 113, p. 137, July 22, 1916. re Allis-Chalmers ball granulator : p. 24, adv., Oct. 13, 1917. • re Senn pan concentrator; p. 24, adv., Oct. 13, 1917. , Rotary roaster for quicksilver ores: vol. 90, p. 22, Jan. 14, 1905. Describes use of a White-Howell roaster at the Socrates mine. Discussion of metallurgy of quicksilver at meeting of San Francisco Section of A. I. M. E., vol. 116, pp. 465, 478, April 6, 1918. Mining Industry^ vol. 1 to XXV, inc., 1892 to 1916 inc. Contains articles, annually re quicksilver industry and mine developments. Mining Reporter^ The reduction of quicksilver. From advance sheets from Min. Res. of U. S. Explains the methods of extraction in use. 1500 w. Aug. 30, 1906. Mitchell-Roeerts, J. F., re use of caustic soda in flotation : Min. & Sci. Press, vol. 114, p. 362, Mar. 17, 1917. Mulholland, C. a.. Treatment of low ' grade cinnabar ores : Australian Mg. Std., June 8, 1911, pp. 565, et seci. re solution in Na,S and precipitation by zinc liydrate. , Wet method of mercury extraction: Min. & Sci. Press, vol. Ill, p. 346, Sept. 4, 1915. Under discussion in reply to Thornhill re equations. The treatment of low-grade cinnabar ores : Min. and Eng. World, Aug. 5, 1911, pp. 241-242. (Abstract from Australian Mining Standard of June 8, 1911.) MtJLLER, H. E., Der Quecksilberbergbau in Toskana. Gliickauf, 1912 — also discussed in besterreichische Zeitschrift fiir Berg- und Hiittenwesen, vol. 60, 1912, pp. 315-316. Describes practices at Italian ciuicksilver mines. NoRTHEY, G. v.. Concentration of cinnabar ores: Eng. & Min. Jour., vol. 96, pp. 783-784 Oct. 25, 1913. Describes concentration at Manzanita Mine, Colusa Co., Cal. Ohly, Dr. J., The metallurgy of mercurv. General review. 1500 w. Min. Rept. Aug. 11, 1904. Parsons, C. S., re use of caustic soda in flotation: Min. & Sci. Press, vol. 114, p. 362, Mar. 17, 1917. Phillips, William B. Condition of the ciuicksilver industry in Texas : Eng. and Min. Jour. vol. 88, p. 1022-1024, November 20, 1909. Rainer, Roland Sterner — , The present status of quicksilver metallurgy in Europe : Oestr. Zeitsc. Berg- und Hiittenwesen, Sept. 26, 1914. Ralston, O. C. & Allen, Glenn L., Testing ores for flotation process : Min. & Sci. Press, vol. 112, serial, pp. 8-13, 44-49, Jan. 1 and 8, 1916. Randol, J. B., Report of mineral industries of the United States : Eleventh U. S. Census Report, 1890. Contains special report on quicksilver. Reprinted in Report X, Cal. State Min. Bur., 1890, pp. 920-929. , California Quicksilver. An anonymous pamphlet, privately publislied, but apparently compiled by Randol, giving comparative data and costs between Cali- fornian and European properties, San Francisco, 1890. 13 pages. Raymond, R. W., Min. Res. W. of Rocky Mtns., 1874, pp. 379-407, describes quick- silver metallurgical practice. In volume for 1875, pp. 13-14, 173-177, lists furnace equipments at the quicksilver mines of California ; also describes some of the plants. Richards, R. H., Ore Dressing, vol. I, p. 481, 1905; vol. II, p. 1074, 1905; vol. IV, p. 1919, 1909. RiCKARD, T. A., Min. & Sci. Press, vol. Ill, p. 384 re flotation. Rising, W. B. & Lenher, Victor, An 'electrolytic method for the determination of mercury in cinnabar. The cinnabar is dissolved in hydrobromic acid, neutralized with caustic potash, pure KCN added in excess to dissolve precipitate, and the metallic mercury deposited on platinum bv a weak electric current. 400 w. Jour. Am. Chem. Soc. Jan., 1896. ROLLAND, M. G., La Metallurgie du Mercure en Californie : Societe d' encouragement, etc., 1878, pp. 85, et al. Describes quicksilver metallurgj' in California. Rosenlecher, R., Description of the mctliod of dressing quicksilver ores in Tuscany by use of trommel, hand-jig, hand-picking and tie: Berg. u. Hiitt, Zeit., vol. LIV, p. 373, 1895. Sand, Henry J. S., Electro determination of mercury and its separation from silver. Abs. of a paper from Jour. Chem. Soc. London. Describes experimental investi- gations. 1000 w. Min. Rept. Apr. 25, 1907. 358 CAI-IKOKXIA STATK :\IINING BUREAU. SCHNABEL & Louis, Handbook of Metallurgy, vol. II, 2d ed.. pp. 1.30-441, 1907. Describe properties and metalUirg\- of mercurv. SCHKAUF, A., in .Talirl). K.-k. seol. Rciclianstalt, vol. 41. pp. .38.3, 396, 1892. re theory of ore depo.sition at Idria, Austria ; also gives man.v citations of literature I'elative to mercury. Scott, Robert, Modern quicksilver reduction: Min. and Sci. Press, vol. 100, 1910, p. 164, J p. Seamon, W\ a., a volumetric method for the determination of mercury: Eng. and Min. Jour., vol. 87, 1909, p. 1047. Sharwood, "W. J., Tlie determination of mei'ciu\v in cyanide solution and precipitate: Min. & Sci. Press, vol. Ill, p. 6(i3, Oct. 30, 191.5. Describes mercury assays. SiEVEKiNG, re a wet method of treating cinnabar with cuprous chloride: Oestrr. Zeitschr. 1876, No. 2; Berg- u. Hiittenm. Ztz. 1876, p. 161. Simons, Theodore, The concentrator of the Timber Butte Milling Co., Butte, Mont. : Am. Inst. Min. Kn.g., Bull. Sept. 1915, pp. 1295-1316. Gives also flotation costs. Spirek, ViNrENZio, The mercury mining district of Monte Amiata, Italy. Gives the location and describes the deposits, method of working production, treatment, etc. Illus. 5000 w. Min. Mag. (N.Y.) Apr. i:i06. , The quick.silver industry of Italy: Mineral Industry, vol. VI, pp. 568-582, 1898, Describes the Cermak-Spirek furnaces and condensers in use at Monte Amiata ; and gives cost data, percentage of extraction, and other valuable details. Illus. Notes on quicksilver industry in Italy: Mineral Industry vol. VII, p. 580, 1S99 ; vol. VIII, pp. 493-494, 1900 ; vol. IX, p. 567, 1901 ; vol. X, pp. 559-561, 1902. Sterner-Rainer, Roland, The pi-esent status of ciuicksilver metallurgy in Europe: Oestr. Zeitsc. Berg- und Htittenwesen, Sept. 2 6, 1914. Stovai.l, D. H., Quicksilver extraction: Los Angeles Min. Jour., Aug. 12, 1905. Strauss, Lester W. Modern quicksilver reduction: Min. and Sci. Press, vol. 100, 1910, p. 431, h p. Sweetland, E. J., Quicksilver recovei-ed in the cyanide process. Considers the manner in which it enters into the tailings, and the recovery. 600 w. Min. & Sci. Press, May 21, 1904. Symington, R. B., Present practice in the metallurgy of quicksilver in California : Mineral Industry, vol. 7, New York, 1899. Thornhill, E. B., Wet method of mercury extraction: Min. & Sci. Press, Vol. 110, pp. 873-874, 1915. re Mulholland's method, and method at Cobalt. Recovery of mercury from amalgamation tailing: Am. Inst Min. Enj '»•> Bull. 104. pp. 1653-1657, 1915. Also in Alin. & Sci. Press, A^ol. Ill, pp. 211-212 1915. Thorpe, T. E., A dictionary of applied chemistry; vol. 2, pp. 555-571, 1898. Describes ores of mercury and methods of extraction ; and gives properties and various compounds of this metal. Turner, H. W., Modern quicksilver reduction : Min. and Sci. Press, vol. 100, 1910, p. 431, I p. Wagner, R., re solubilitv of mercuric sulphide in barium sulphide : Jour. Pi-akt. Chemie, vol. 98, 1S66, p. 23. , re a wet method of extracting mercui-y, using bromine water: Dingier, vol. CCXVIII, p. 254; Chem. Centralblatt, 1878, p. 711. Weber, Dr. Rheinhardt, re solution of HgS in alkaline sulphides : Poggendorff, Annalen, 4th series, vol. 7, 1-56, p. 76. Weinschenk, E., in Zeitschr. Kryst. Min., vol. 17, p. 498, 1890. re preparation of cinnabar artificially. Whitney, J. D., The Coast Ranges: Appendix, Cambridge. (Uniform with publica- tions of the Geological Survey of California, by J. D. Whitney. State geologist.) Second Geol. Survey of California, Geology, vol. 2, pp. 91-135, 1882. Contains report on examination of quicksilver mines of State, by W. A. Goodyear, May, 1871; and includes descriptions of furnaces and their operation. Whitton, W. W., The determination of mercury in ores: California Jour. Tech., vol. 4, No. 1, pp. 36-39, September, 1904. Gives a modification of the distillation assav. ZIPPE, P. X. M., Geschichte der Metalle, 1857, p. 208, re preparation of vermilion from cinna))ar, by the ancients. Part B: rv Califoniian oci-iirrences on geology, mineralogy, and mine equipments. ASHBURNER, WiM.iAM, Report of the Sulpluir Bank Quicksilver Mining Co.. Lake County, Califoinia, 1S76, p. 5. Contains reports by William Ashburner, James D. Hague, Tliomas Price, and M. C. Vincent. A general description of the Clear Lake i-egion. Baverstock, R. S., Quicksilver: Min. & Sci. Press, vol. 84, 1904, p. 2. . Contams gen- eral notes on treatment and California deposits. Beck, R., and Weed, W. H., Nature of ore deposits, New York and London, 1905, pp. 350-360. Becker. George 1''., Geologv of the quicksilver deposits of the Pacific Slope: Mon. U. S. Geol. Survey, vol. 13, 1888; Abstracts. Am. Geology, vol. 5. pp. 178-180; Am. Naturalist, vol. 24, pp. 850-851; Am. Jour. Sci., 3d ser., vol. 39, pp. 68-69; Eng. and Min. Jour., vol. 49, pp. 137-138. , Sununarv of tlic geolog>- of the quicksilver deposits of tlie Pacific Slope: Eiglitli Anii.'Rept., IT. S. Geol. Smvoy pt 2, 1889, pp. 961-98.=;. QUICKSILVER RESOURCES. 359 -Rfcker G F Qiiuksilver ore deposits: Mineral Resources U. S. Geol. Survey for 1802 Dn'l30-16S ISi^S Describes the occurrence of mercurial deposits in the United States and foreign countries. Deposits occur as fissure veins, impregnations, and Tn' zones of broken country rock. Tables of production , t , „f th» Statistics and technolosry of the precious metals; Geological sketch of the Pacific Division: Tenth Census of the U. S., vol. XIII, pp. o, I0-I6. IS, 19, Jl, ^i. Am'. Jour. Sci.. vol. 31, p. 120, 1886; re formation of cinnabar and metacin- 24, 2.^. 26, 1885. -. in BERi^^?E.f'z\^nc^!er'v^; Californien : Zeits, fur Kryst., 1878, vol. 2, p. 19.; also RuU Soc Fr Min.. 1881, vol. 4, p. 87. . , ^ ..-,, -Rlack's' Supreme Court Reporter, vol. 2: The United States vs. Andreas Castillero. before the Supreme Court, December term. 1862. The testimony gives liistory of quicksilver discovery and early development in California, with particular voference to New Almaden. . . ^ ,-.■.-,■, BLAKE William P.. Quicksilver mine of Almaden, California: Am. Jour, bci., 2d ser., ^^'N^W^m^the'o'cSuVence of gold with cinnabar in the Secondai^ or Tertiary rocks rCalifornia] : Proc. Boston Soc. Nat. Hist., vol. 11, 186S, pp. 30-,31. --Annotated catalogue of principal mineral species hitherto recognized in Cah- !^"tote''sS^f Ifsementf de^Sna^^^^^^^^ la Californie et du Nevada: Bull. Soc. Boutwell!"j. M',%uSiJfu''er? Mineral Resources U. S. for 1906, Geol. Survey, 1907, Br^d^l^ey^ wIlter W , Mines and mineral resources of the counties of Colusa. Glenn, Lake Marin Napa, Solano, Sonoma, Tolo : chapters of State Mineralogist s report IMennial period. 1913-1914, Cal. State Min. Bur., 1915. Includes descriptions of ^'^'wUh G c'^Brown, F. L. Lowell, R. P. McLaughlin: Mines and mineral resour- ^; of the counties of Fresno, Kern, Kings, Madera, Mariposa, Merced San Joanuin Stanislaus ; chapters of State ^lineralogisfs report, biennial penod, l°13-l?i4 Cal State Min Bur., 1915. Includes descriptions of quicksilver mines. il the above chapters included in Report XIV, of State Mineralogist, 1916. ' ^uh E Hugifenin C. A. Logan. C. A. Waring, Mines and mineral resources of ^e'ountfes of^Monterey, San Benito, San Luis Obispo, f "j':^ ^artara, ^ entura^ chapters of State Mineralogist's report, biennial period, 191o-1916, Cal. btate Min Bur 1916 Includes descriptions of quicksilver mines ,„„i^,. /;„ till preceding chapters included in Report XV of the State Mineralogist (in Browns'g^'Chester, Mines and mineral resources of Shasta, Siskiyou. THnity counties : chanters of State Mineralogist's report, biennia period, .l''l-^-l^V;=i^^Vb«^tert mVii Bur 1915. Includes descriptions of quicksilver mines. These chapteis Rockv Moimtalns, by J. Ross Browne, special commissioner, T\ aslunslon, 1S6,, L^; DoVn^n .lie cln„.,.,ar mines Acoonn. ot a vl'lt to New Aim.,ae„ in 1865. ^'? • V-.P^: r PP ''i.'^Vo^^^fiV^ 1888 vof ix pp. 209, 330, 337, 1889; vol. X, -J='^M^iS^'i^''^;^S^V£^rSi^^^'ci^^'^'-'^. .,,- wm. Forstner. .003. __^"'B;liai"6f'-Mini?ffiorSfS&s,"rA.,S. EaKle. 1914. I„ci.i 1911; mercury, pp. 633-638. ^ ^ ^ ^ .. ..„ ^^ ^f., (.(.q iqig , Data of Geochemistry: U. S. G. S., Bui . 616 pp 664-669 191b. ..ilv-Hsst=or°yire,s,'Sffo?t|ifeS;ii^:^,°'''''- "■"""■'■ DANA, J." D.' System of Mineralogy, 1868 (or later editions) De KALB, CoukTENAY. Guadalupe quicksilver works: Mm. and Sci. Pi ess, ^ol. 100, DE LlcxA^Y^-Tr&'e'de^^etallogenie, etc., vol III. Paris. 1913; re mineral deposits, including California. 360 CAT.IFdRXIA STATK MIN'TXC P-fREAU. Demaket. Leon, Les principaux Kisemonls des minerals de mercure du monde. Annalos des mines de Belsiqiu', vol. 9. 1904. Gives an account of deposits of quiclvsilver ores in tlie world, occurrence, etc. In tlie United States tlie deposits in California, Oregon, and Texas are considered. DURAND, F. K., Notes on crystals of quartz containing cinnabar: Proc. Cal. Acad. Sci., 1S68-1872, vol. 4, p. 211. , Description of a new mineral from the New Almaden mine: ibid, p. 218. , Notes on the crystallizatiiin of metacinnabarite : ibid., p. 219. Eakle, Artihiu S.. Minerals of California, Cal. State Min. Bur., Bull. No. 67, 1914 — includes desci-intions and loiMlitics of various mercury minerals. Contains also a bibliography on California minerals. Eddy, I>. II.. Quicksilver in California in 1910; Eng. and Min. Jour., vol. 91, 1911, p. 85. Edwards, C. E.. California quicksilver industry: Min. World, Feb. 24, 1906. Egleston, T., Mercury associated with liitumen : Trans. Am. Inst. Min. Eng., vol. 3, 187.T, p. 27.3. Emmons. Samuel Franklin, Geological distribution of the u.seful metals in the United States Trans. Am. Inst. Min. Eng., vol. 22, 1894, pp. .53-95 and 737-738. Describes the geologic occurrence in different parts of the United States of quicksilver and other minerals and gives a summary of conclusions coijcerning genesis of their ores. Emmons, W. H. The enrichment of ore deposits, U. S. G. S. Bull. 625, pp. 392-398, 1917. Eng. & MiN. Jour., editorial correspondence, re Oceanic mine in San Luis Obispo County, Cal.: vol. 102, p. 512, Sept. 16, 1916. Fairbanks, Harold W., Some remarkable hot springs and associated mineral deposits in Colusa County, Cal. : Science, vol. 23, 1894, pp. 120-121. Describes the occur- rence of hot springs and the associated gold and quicksilver deposits in this county. , Notes on the geology and mineralogy of portions of Tehama, Colusa, Lake and Napa counties: Cal. State Min. Bur., Report XI, pp. 54-75, 1S93. Forstner, William, The quicksilver resources of California : Bull. Cal. State Min. Bur. No. 27, 1903. Reprinted, 190S. Includes chapters on condition of quick- silver, geology of quicksilver belt in State, genesis of quicksilver ore deposits, mines. , The quicksilver deposits of California: Eng. and Min. Jour., vol. 78, 1904, pp. 385-386, 426-428. Gabb, W. M., Communication on the San Luis Obisjjo quicksilver fossils: Proc. Cali- fornia Acad. Sci., vol. 3, 1863-1868, p. 193. Gillan, S. L., Cinnabar in the Sierra Nevada: Min. & Sci. Press, vol. 114. p. 79, 1917. Describes a deposit at Tehachapi, Kern Co. Goodyear, W. A., Report on an examination of the quicksilver mines of California (May, 1871) : Geol. Surv. of Cal. (Whitney), Geology, vol. II, Appendix, pp. 91-135, 1882. Describes mines, geology, and furnace practices. Illus. Hart, T. S., Notes on the Almaden mine, California: Am. Jour. Sci., 2d ser., vol. 16, 1853, pp. 137-139. Heberlein, C. a.. The mining and reduction of quicksilver ore at the Oceanic mine, Cambria, Cal, Bull. Am. Inst. Min. Eng., Feb., 1915, pp. 497-504 ; also Trans, vol. LI, pp. 110-119: Illus. Hillebrand, W. F., re Coloradoite in California: Am. Jour. Sci., vol. A'lII, p. 295, 1899. Horton, F. W., Quicksilver: Mineral Resources of the United States for 1905, U. S. Geol. Survey, 1906, pp. 393-404. Hugbnin, Emile, et al authors,. Mines and mineral resources of Monterey, et al counties: chapters of State Mineralogist's report, biennial period, 1915-1916, Cal. State Min. Bur., 1916. Includes descriptions of quicksilver mines. These chap- ters included in Report XV of State Mineralogist (in press). Janin, Louis, Jr. Mining and metallurgy of quicksilver in California : Report for 1873 on mineral resources of the States and Territories west of the Rocky Moun- tains, bv R. W. Raymond, special commissioner, Washington, 1874, pp. 379-407. Kemp, J. F., Ore deposits of the United States, 3d ed., 1900, pp, 424-428. Lakes, A., New Almaden mines of Santa Clara County: Mines and Minerals, vol. 19, 1899, pp. 346-349. Lawson, a. C, U. S. Geol. Survey Geol. Atlas, San Francisco Folio (No. 193), pp. 3-4, 22, et al, 1914. Describes and discusses Coast Range geology, and notes quick- silver occurrences within the area covered by the folio. Colored maps and sec- tions. Le Conte, Joseph, and Rising, W. B., The phenomena of metalliferous vein formation now in progress at Sulphur Bank, Cal: Am. Jour. Sci., od ser., vol. 24, 1882, pp. 23-33. Le (5onte, Joseph., On mineral vein formation now in progress at Steamboat Springs compared with tlic same at Sulpluir Bank: Am. Join-. Sci., 3d ser.. vol. 25, 1883, pp. 424-428. Lindgren, W., and Turner, H. W., Placerville folio (No. 3), California: Geol. Atlas of U. S., U. S. Geol. Survey, 1894. Mentions occurrences of quicksilver in this area. , and , Smartsville folio (No. 18), California: Geol. Atlas U. S., U. S. Geol. Sui-vey, 1895. Gives a general dcsi'iiption of tlu' gold l)elt of Cali- fornia and generalized columnar section of tlio foiinations of tlie region. Describes different formations and occurrence of (luicksilvir. luchnlcs toiiogr.-ijiliic and other maps. The gold quartz veins of Nevada City and Crass Vallc.v : U. S. Geol. Surv., Ann. Rep. 17. Part 2, 1895-1896. QUICKSILVER RESOURCES. 361 Logan, C. A., et al autlmrs. ?i[ines and mineral re.sourc(>s of Moiiteivy. ct al counties: chapters of State Minei-alosisfs report, biennial period, IDiri-l'ilG, Cal. State Min. Bur., 1916. Includes descriptions of quicksilver mines. These i-hapters included in Report XV ol" State Mineralosist (in press). Lowell, F. H., Quicksilver for 1910: Min. & Sci. Press, vol. 102, 1911. p. 62. Lowell, F. L., et al authors. Mines and niineial resources of Fresno, et al coimties: chapters of State Mineralogist's report, biennial report, 1913-1914, Cal. State Min. Bur., 1915. Includes descriptions of quicksilver mines. These chapters included in Report XIV of State ]\Iineralogist, 1916. Lymax, C. S., ?ilines of cinnaliar in upper California: Am. Jour. Sci. 2d ser vol 6 18-18. pp. 270-271. Mason, Richard B. Letter from Col. Richard B. Mason : Reports of the Secretary of War (H. Doc. 17, 31st Cong., l.st sess.), 1850, pp. 528-536. Gives a description of the quicksilver mines near San Jose. McCaskey, H. D., Quicksilver: Mineral Resources of the United States for 1907 U S Geol. Survey, 1908. pp. 677-692. , Quicksilver: Mineral Resources of the United States for 1908, U. S. Geol. Survey, 1909, pp. 683-695. , Quicksilver: Mineral Resources U. S. for 1909, pt. 1, U. S. Geol. Survey, 1911, pp. 549-559; also in Min. Res. for 1910-1916 (inc.). , Quicksilver: Mineral Resources U. S. for 1910, pt. 1, U. S. Geol. Survey, 1911, pp. 6't3-710. Contains also a bibliography on North American occurrence.s. McGarrahan, William, The quicksilver mines of Panoche Grande. Washington, 1860. Melville, W. H., Metaclnnabarite from New Almaden, Cal. : Am. Jour. Sci., Vol. 40, p. 293, 1890. , Metaclnnabarite from New Almaden, Cal. : Bull. U. S. Geol. Survey No. 78, 1891. pp. 80-83. and Lindgren, W. Contributions to the mineralogy, of the Pacific Coast : Bull. U. S. Geol. Survey No. 61, 1890. Studies of cinnabar minerals from California quicksilver mines. Mineral Industry, vol. I to XXV, inc., 1892 to 1916, inc. Contains articles, annually re quicksilver industry and mine developments. Min. & Sci. Press, Quicksilver in California, vol. 74, pp. 253, 257, 1897. , Quicksilver, re Abbot mine gas, vol. 76, p. 80, 1898. , Reduction of cinnabar at Sulphur Creek, California, Mav 27, 1905. , Quicksilver in California, vol. 100. 1910, pp. 15-16. , The quicksilver situation, vol. 100. 1910, p. 789, i p. Mining World, Feb. 24, 1906. re New Almaden mine. Moore, G. E., re "metacinnabar" : Am. Joui. Sci., ser. 3, vol. II, Jan. 1872. Newland, D. H., Quicksilver: Mineral Industry, vol. 12, New York, 1904. Parker, Edward W., Quicksilver: Twenty-first Ann. Rept. U. S. Geol. Survev. pt. 6, 1899, pp. 273-283; 1901, pp. 656. Penfield, S. L., Crystallized tiemannite and metaclnnabarite: Am. Jour. Sci., 3d ser., vol. 29, 1885, pp. 449-454. , Notes on the crystallography of metacinnabarite : ibid., 1S92. ser. 3. vol. 44, p. 381. Phillips, J. S.. and Louis, H., A treatise on ore deposits, 2d ed., 1896, pp. 117, 135, 143, 747, 791. Phillips, William B., Geology of quicksilver deposits: Min. World, vol. 29, 1908, p. 131. Tabulates the geologic relations and associated rocks and minerals of quicksilver deposits. POSEPNY, F., The genesis of ore deposits: Trans. Am. Inst. Min. Eng., special pulilica- tion. New York, 1902, pp. 32, 66, 256. Account of quicksilver mine at Sulphur Bank, California. Randol, J. B., Quicksilver in California: Report of 1875 on mineral resources of the States and Territories west of the Rocky Mountains, by R. W. Raymond, Wash- ington, 1877, pp. 4-21. , Report of mineral industries of the United States : Eleventh U. S. Census Report, 1890. Contains special report on quicksilver. Reprinted in Repoi't X, Cal. State Min. Bur., 1890, pp. 920-929. Ransome, F. L., Mother Lode District, folio (No. 63) : Geol. Atlas U. S., U. S. Geol. Surv., 1900. Mentions occurrences of quicksilver in this distiict of California. Rath, G. von, Berichte ueber die L'mgebungen von San Francisco, Santa Cruz, und Neu Almaden, California: Vortrage und Mittheilungen, 1886. Raymond, R. W., Notes on the Almaden mines and on the mother lode of California: Report of 1869 on mineral resources of the States and Territories west of the Rocky Mountains, by R. W. Raymond, special commissioner, Washington, 18 70, pp. 9-11. , vol. for 1871, pp. 15-16, 528; 1872, p. 523; 1873, pp. 9-11, 497; 1874, 27-39 (mines), 379-407 (metallurgy) ; 1875, pp. 13-21, 173-178, 179-189; 1876, 4-21. Rearden, Phil, Some occurrences of gases in a ux regulation 240 Fire-bricks, cost of 235 FiriuK, fuel, resnlation of__-- 240 Fitzgeraltl furnace, or inclined retort 85, 216 'Flask' of quicksilver defined 10 Flasks, cost of 190 Flagstaff mine 187 Flint group _-_-_ 9S Florence Mack mine 103-105 Flotation at B?Ila-Union mine — 337 at New Almaden 344 concentrates at New Almaden mine 344 oil attached to -- 339 concentration by -- 300-320 experiments at New Idria mine 342 at Oceanic mine — 339 fine grinding for, costly 343 machine, K. & K 80 machines, laboratory 300-303 practice, large scale 319 Process, The 355 results, resume of 314-320 selective, of pvrite, with cinnabar 315 test, froth on -- 302 testing manipulation 319-320 tests, author's __ -- 305-317 oils used in 303-305 Flouring of ciuicksilver by water-spray in condensers 192, 262 Flow-sheet of Manzmita concentrating system 331 of New Idria plant 340 New Idria revolving- furnace plant 249 I'^luor.spar 29 Foil, gold and silver, for Whitton apparatus _ 285 Formation of mercury sulphate 236 I'ormutions, age of. in New Almaden district 155 geologic, of middle Coast Ranges 17 Form of ore deposits 23. 24 Forstner, Wm. 7, 15, 18, 22, 30, 32, 34, 39, 53, 77, 82, 85, 86, 94, 96, 103, 125, 126. 154, 161, 163, 202, 210, 216, 220, 223, 231. 233, 247, 261, 330, 338, 355, 360 Fouque & Levy -- 365 Fourth of July mine 98 Franciscan formations, quicksilver in IS group __ ^ 19-20 rocks in the Diablo Range 197 Francis claims 50 Fianklin prospect 61 Freezing point of mercury 208 l>"rench Ranch mines 105 Fresno County, mines in 43-4(! New Idria district formsrly in 43 (|uicksilver production of 43 ]'"riction sin-faces in condensers 260 l''iuth on a notation test 302 Fuel c msumption ii Scott furnaces 239-240 (•onsumption in Herresclioff fiii-nace 252 costs 15, 57, 68, 75, 79, 86, 89, 107, 118, 122, 131, 138, 1S6 feeding 240 Fuel-oil co.sts 45,342 effect of. on amount of soot produced 274 use of, in quicksilvei- fumacis 16, 49, 118, 166, 185, 189, 255 Fulminate, substitutes for 9 use of ([Uicksilver in manufacture of 9 Fume losses from Scott furnace 268-270 traps for fine-ore furnaces 241 Fiirman's Manual 355 I'urnace gases, data on 238-239 temperatures -- 118 Gabe, W. M 360 Galera 29 Gandoin, M. 355 (Jiungui' mini'i-als 28. 29 INDEX. 375 Page Gases at Sulphur Bank mine 291 furnace, data on-_-- 238-239 Gas leakage in coarse-oi'e furnaces . 225 Gasoline motor, ore haulage with 113 Gates table 294,295 Geary, J. W 355 General Mines Company 204 Naval Stores Company 317 Geograpliical distribution of quicksilver deposits 17 Geological map of Clear Lake district 32 Coi'ona mine S2 Mayacmas district 30 New Almaden district 15 1 New Idria district ;m quicksilver districts in San Luis Obispo County 12 1 St. John's mine 173 Stayton district !)6 Sulphur Bank mine 66 Sulphur Creek district 33 Geologic formations of the middle Coast Ranges 17 Geology, bibliography on 358-362 of New Almaden district 154 mine 161-163 New Idria mine -- ^ 109-112 Oceanic mine 142-143 quicksilver deposits -- 17-24 St. John's mine 173-179 Georgia Pine Turpentine Company '-- 305 George mine 134 Geyser mine 185 Gibson, A. A 206, 287 Giga.x claims 198 Gillan, S. L 360 Gilleland, A. C. 303 Gilpin County (Colorado) bumping tables 335, 336 Glass tube assay method ■ 277 Glazed sewer-pipe in condensers 180, 262 Glenn County, cinnabar in --. 46 Gmelin-Kraut — 355 Gold associated with cinnabar -- 67 with quicksilver . -- 98, 109 foil, use of, in Whitton apparatus 285 native 28, 29, 38 in Manzanita mine — 38 use of quicksilver in recovery of, by amalgamation 9 Goldbanks mine, Nevada 292, 293, 30S, 310, 312, 315, 322 Herreschoff furnace at -- 253-254 ore sample from . 288 specimen from , 25 extreme fineness of cinnabar in .- 289, 315 flotation tests on -- , 315 solution tests on 322 Goodale. C. W 268, 356 Goodvear, W. A 160, 164, 236, 262, 329, 356, 360 Gould, H. W 206, 207, 24S, 250 mine -- -- 1 Hi Government price for quicksilver, 1918 15 Grade of quicksilver ores being worked 15 of concentrates 332 Grahamite 189 Gravel-washing plant for recovery of metallic quicksilver 345 Grayson mine -- 198 Great Kastern mine 22, 181, 187-190 associated minerals of 29 conce itration at . 337 drying ore at 255 effect of oil as fuel at 274 fuel-oil used at -- IG natural bitumen in ■ 189 proiuction of 187 soot at 274 Great Falls Copper Plant, settling flue experiments at 268 Great Northern group 190 Great Western mine 22, 58 associated minerals of 29 concentration at __ — '■ 58, 337 Litchfield furnace at 226, 234 Griffith, Andre P 356 Grigsby mine 90 Grinding contact, formation of mercuric sulphide by 324 of ore at New Almaden for flotation 343 Grizzly claim 204 Guadalcazaritf _ -- 27 Guadalcazar, Mexico, assjciaterl minerals of 2'.l 376 INDEX. Page Guadalupe mine 33, 154, 1.56, 157-160 automatic furnace charging at 235 concentration at 160, 345 plant of 158 rotary ore-drier at 255 Guilett, M. L 356 Gypsum 29 Halse. Edward 356 Hamilton, Bfauchamp and Woodworth 298,315 Hamilton. E. M 356 Fletcher 206 Quicksilver Mining Company 77 W. H. ___-- 290 Hanks. H. G 329, 356 Harrison mine (see also under January mine) 204 concentration at 346 Hart, T. S 360 Hasenclever furnace 231 Hastings mine -- 171-172 Neate furnace at 223 Hays mine : 59 Hayward mine 198 Heberlein, C. A 241, 338, 339, 356, 360 Helen mine 52, 59-61, 312, 316, 322 ore, flotation tests on 316-318 pyrite in 317 sample from 290 Helmacher, R. 356 Hendy, Joshua, Iron Works -- 214 Hepatic cinnabar __ 25 Hernandez Quicksilver Mining Company 105-107 Herreschoff multiple-liearth furnace 165, 250-254 at Goldbanks mine, Nevada 253 cost of -- 252 fuel consumption of 252 percentage of extraction by 253 size of feed for 251 Hersam, E. A -- 206 Hershev, O. H.__ ___-- 173 Hillebrand, W, F 26, 27, 356, 360 Hillsdale mine 160 Hollind. G. 361 Horton, F. W 360 Hoover. H. C. 207, 356 L. H. 207, 356 Hope mine __ 191 Hot salino-sulpliur springs at Elgin mine 37 springs, association of, with quiclvsilver deposits 22, 156 associated with qviicksilver deposits of Sidpliur Creek district 32 at Sulphur Bank mine 66,67,291 Huancavelica mines, Peru 161 associated minerals of 29 Kuguenin, Kmile __— 7, 46. 151, 204, 346, 360 Huitzufo. Mexico 29 Humboldt County, cinnabar in 46 Hunttarian copper mines, associated minerals of 29 Htnlcv pi-ospect -- 190 lltittnor, H. J 209, 231 Hiittner-SciHt fine-ore furnace (see also under Scott) 161, 231-246 Hvde flotation machine 300, 317 sub-ae'atinn in 317 Hvdraulic sluicing to recover metallic quicksilver 345 Hydrocarbons associated with quicksilver ores 23 Ice-cream frrezer, use of, in flotation tests 314 Idria, Austria, associated minerals of 29 (■()nc?ntration at 329 lump trap at 241 mines 161, 356 ore deposits of 21, 22, 24 sampling at -- -- 246 Idrialite 23 Import duty on quicksilver 13 Imports of quicksilver into tlie United States 13 Indicated extraction by Scott furnace 245, 246 Inilicating pyrometers :_ 239 Inncs fume trap 241 Murray 207, 264, 338, 356 I'lsuliiti d walls in a Scott furnace 235 Inlegtal mine __ 200, 202, 330 Knox-Osborne fine-ore furnace at 227 Interest charge.s 353 Interfi'riiig elements to alkaline sulphide methods 326 Intc)-n-,ilio!ial mine 198 INDEX. 377 Page Inyo County, quicksilver in 46 Ippen, J. A 356 Iron as a desulpluu-izer 209 filing's, as a desulphurizer 282, 284 retort, effect of excess sulphur on 350 'Iron-clad' Scott furnaces , 231, 235 Ivanhoe Quicksilver Mining Company 169 James assay apparatus 277 G. A. 356 Creek placers 82, 90 concentration in 335 Creek prospect 90 Janda, F. _— 356 Janin furnace — 140 Louis, Jr. 356, 360 January mine (see also under Harrison mine) 204 concentration at 205 Jewess prospect — 61 Johnson-McKay retort 213-215 condensers on -- — 257, 261 construction of 214 cost of — 1. 215 materials for 214 Jory. J. H -- 356 Josephine group 134 mine 126, 138 Joshua Hendy Iron "Works " 294 Jurassic-Cretaceous rocks, quicksilver in 18 K and K flotation machine — SO, 337 Karl mine (see also under Klau) 126,135 Scott furnace at 234, 254 Keane, C. A 356 Kemp, J. F 360 Kentucky mine 185 Kerl, B. 356 Kern County, mines in 47-49 Keystone mine 134 King Magnesite Company ' 51 King of All group 70 Kings County, mines in 50-52 quicksilver production of — 50 mine, concentration at 51, 338 Quicksilver Mining Company, Ltd 50-52 Kirchhoff, G. S. C— 321,356 Kirwan, T. D 290, 317, 318 Kismet group 135 Klau mine 126, 135-138 ore drier at ^ 254 retorts at 215 Kleinite __-- : 27 Klepinger, J. H . ■ 268, 356 Knox, J. 356 Knox-Osborne coarse-ore furnace 220, 221 fine-ore furnace -- 227-228 iron condensi^rs -- 255, 256 Knoxville district 33, 52, 204 associated minerals of 29 transportation to 33 formations, quicksilver in 18 mine -_ 33, 82-84 production of -- 83 mines, production of 76 seiies in St. John's mine 174 Knoxvillite __ 28, 83 Kongsbei'gite 26 Koninck, L. L. de-- 356 Krieckhaus volumetric assay method 277 Kuss, M. H.__-- 356 Laboratory apparatus for flotation tests-- 300-303 flotation manipulation 319-320 "Ladder veins' 188 La Joya mine 84-86, 298 Livtrmore furnace at 229 Livingston fui'nace at 216, 217 map of -- 84 ore sample from 290 Lake County, mines in -- 52-70 (luicksilver districts, geological map of 32 quicksilver production of 53 mine -- 76. 86 Lakes. A. 360 La Libertad mine 126. 138 Lang. H rhert 356 378 INDEX. Page Landei's continuous retort 217-218, 350 lost of 218 W. H. 166, 250, 274, 352. 356 Large chamber condensers _258-270 ]>nwson, A. C 17, 18, 19, 20, 35, 206, 360 I^enkajio of sas from coarse-ore furnaces 225 1.0 Coiite, Joseph 360 Jjelunan mine 127 J^clirbacliite -- 27 Leiilier, X'ictor 357 Lcvifjlianiti' 27 Lewis. R. S 31 1, 356 Liebenow, C. 356 Lifflithouses, use of quicksilver in 9 Lilian! retort 217 Lime as a desulphurizer 75, 209, 284 cost of 75 use of. in retorting 75 Lindblom Bros., concentration by 335 mine __ 82 Lindsren. Waldemar 18, 21, 22, 26, 46. 92, 188, 203. 360 Linold. M. V 356 Litchfield furnace -- 226, 227. 234 Little Bonanza mine 138-139 Sulphur Bank — 67 Livermore furnace — 226, 227, 229-231 'Liver ore' 25 Livingston furnace 85-86, 216-217 Livingstonite 27 Llewellyn Iron Works — 332 Logan. C. A 7, 104, 125, 147, 244, 338, 361 Lone Star mine 107 Lookout group 190 Los Angeles County, quicksilver in 70 Los Pieachos mine 105 Peak 106 Los Piietos district .. 34 group .30 mi.ies -- 150-152 Losses at New Almaden 246 ))y means of water 270 from Scott- furnace 241-243 of fume from Scott furnace 268-270 Louis, H. -- -- 361 Low, A. H 277, 356 Lowell. F. H -- _-- 361 F. L. --__ 7. 109, 361 Lucitta mine __ 61 Lucky Boy mine, Utah, mercury selenide in 27 Stone group -- 190 Luckhardt, W. G -- 291 Lunge, G. -- 356 Lyman. C. S. - , 361 Mactear, James 356 Madrone mine 139 Magnesite 28 associated with cinnabar --_ 97 in serpentine 95 Mag.iolite -- — 27 Malmnev mine 126. 140 Munliattan mine -- • 22, 33. 76, 86-87 Knox-Osborne coarse-ore furnace at 220 tine-ore furnace at 227 Manning, Van H -- 207 Manzanita mine 32,38 associated minerals of 29 concentration at 39, 330-331 r. torts at 210-212 Map, gi'ological. of Corona mine , 82 geological, of Lake Count.v districts 32 Mayacm.is district 30 New Almaden district 154 New Idria district 94 San Luis Obispo quicksilver districts 124 St. Jolm's mine 173 Stayton district 96 Sulphur Bank mine 66 Sulphur Creek district 33 of Abbott mine 54 Cambria mine 129 ]..a Jo.\-a mine 84 New Almaden mine 161 New Idria mine 110 Ociaule mine 142 outline, of California showing distribution of quicksilver d^^-posits 17 INDEX. 379 Page Maps of St. John's mine 173^ 176^ 17g Marensite '_ 28 29 Mariconia prospect Z^_Z 190 Marin County, quiclvsilver in I_~ 70 Mui'ier. F. E -- I 3O4 Maripcsa County, cinnabar in I_ 7] mine 105 M irc|uait Rancli prospect 140 Mason. R. B 2 361 Materials for condenser construction 261, 262, 265, 267 for construction of Scott furnaces I_ ' 2.T5 Mayacmas district -- 30-32, 52, 181 geological map of 1 ' 30 Maypole prospect -- 61 MeCaskey, H. D 13,361 McGarrahan, William ' 36I McDermott, Walter 357 McDousall furnace 250 Mehu, M. C 357 Melyille. W. H 16,361 Mendocino County, ciuicksilyer in 71 Merced County, quiclisilver in 72 Mercey Mining and Development Company 44 Mercur claim 152 Mercurial soot, analyses of 272 Mercury Company of America 169 electrolytic deposition of, from solution 328 .s:roup (San Bernardino County) ^ 123 group (Sonoma County) -- 193 minerals 25-29 Mining Company 193 mist, recovery of 267-2^9 native — 26 concentration of 193 in Alpine mine 97 Big Injun mine ■ 57, 288 Cambria mine 288 Esperanza mine — 186, 289 New Sonoma mine: 191 Pine Plat district 181 Rattlesnake mine -- 192 Socrates mine 193, 195 Wall Street mine — 69 properties of 208-209 selenide — 193 solubility of, in alkaline sulphide solutions 321 sulphate, formation of 81, 326 sulphide, formation of, by dry grinding 324 telluride 203 wet methods for extraction of , 321 Metacinnabarite 26 in Culver-Baer mine -- ^ . 185 Hastings mine -- 172 New Idria mine 95, 112 Reed mine : 205 Metallic quicksilver, recovery of, at New Almaden 344-345 recovery of, by Senn amalgamator 276 Metallurgy, bibliography on — 354-358 Depaitment of, University of California 5 of quicksilver 206-353 'Metamoiphic series' 18 Method (if mining at Oceanic mine 143 Mexican mine 43 Middletown prospect -- 62 Middlings samples 1294 et scq. Mieres, Spain -- - 29 Milburn, Carl 151 Milburn-McAvoy group 150 Military necessity of quicksilver 9 Miller, .1. E. 206, 287 W. P. 330 Millerite 28, 29 Milling costs at Manzanita mine ; 331 Mill of D partment of Mining, University of California 286 Mine e(iuipments. bibliography on 358-362 Hill workings of New Almaden mine 162 Mineral Industry __-- 357, 361 Mini'i-alogy, InbliogTaphy 01 358-362 Minerals of mercuiy, or ciuicksilver _- 25-29 Separation Company 317, 342, 349 380 INDEX. Page Mining and I-lnsineering Review 357 and Sriontilic Press 214, 357, 361 quicksilver quotations in 12 Industry 357 inetliod in Oceanic mine 143 Reporter 357 World 361 Minnelialia mine 169 Mirabel mine 62 Scott furnace at 234 Mispickel __ 29 Missouri mine ; 185 Mist, mei'cury, recovery of__ 267-269 Mitchell-Rolierts. J. F 314, 357 Modoc Cinnabar Oroup 72 County, quicksilver in 72 mine 126 Mobr pipette, use of, in measuring oils 303, 319 Moisture in ore, effect of, in roasting 240 Mono County, linnabar in 72 Monte Amiatn, Italy, associated minerals of 29 Cerm.ak-Spirek furnaces at 227 condensers at — 256 soot at ; 209 Cristo group _- 73 Monterey Cormt.\-, mines in 73-75 group 99 mine 93 Montroydite — 2S Moore, G. E 361 Morley, W. A 206 Morning Star mine 99 Mother Lode Gold Belt, cinnabar in 203 Mountain mine 87 Mount Sam Mining Company 61 Mt. Boardman Quicksilver Company 197, 198 Diablo, quicksilver on 41 Jackson mine 188, 190 Shasta Cinnabar Mine 169-170 mine, concentration at 170 Vernon claim 183 Mudrock in Oceanic mine — 141 Mulholland, C. A __ — 323, 324, 328, 357 Muller, H. E — 357 Multiple-hearth furnaces 250-254 Myrickite -- 123 Napa Consolidated mine (Oat Hill) 88 associated minerals of 29 County, mines in 76—91 production of --__ 76 prospect -- 191 Napalite 23 Native mercury _- 26 concentration of 193 gold associated with cinnabar 28, 29, 38 in Big Injiui mine 2SS Cambi-ia mine 288 Esperanza mine 186, 289 New Sonoma mine 191 Rattlesnake mine — 192 Socrates mine 193, 195 So'ioma County 181 quicksilver (see also under mercury). concenti-ation of 337 recovery of, by tables 299 sulphur at Sulplnir Bank mine 290, 346 Neate coarse-ore furnace 220, 222-223 Neill jig __-- 333, 334 Neocomian formations 18 Nevada Cinnabar Company, solution tests on ore from 326 County, (•innal>ar in__ 92 New Ahnaden Company 217 district 33 age of formations in 155 geDloglcal map of 154 mine 14, 17, 24, 33, 154, 155, 156, 160-167, 262 absorbed quicksilver at 242, 243 associated minerals of 29 concentration at 167, 343-346 condensation of (luicksilver vapors at 259-261 cost of fine griniling at 349 devel()|imi'nt of Scott furnace at 231 discovc'ix- of. by Andi-eas Castillero 154 INDEX. 381 New Almaden Company — Continued. * mine — continued. Page Exeli furnaces at 220 experiments of S. B. Clirlsty at 246 extraction at 246 flotation concentration at 344 fuel oil used at 16 geology of 161-163 Herreschoff furnace at 250-253 map of 161 ore specimen from 25 per-Ilask cost production at 343 production of 161 reduction equipment of . 164-167 Scott furnaces at 234 soot treatment at 271 treatment losses at 246 window glass in condensers, at 264 Newcomb, B. JVI 117, 206, 223 R. P. 206. 213, 332 New Discovery Quicksilver Company -- 160 Elgin Quicksilver Mining Company 36 England mine 204 Guadalupe Mining Company 157 Newhall, H. M., and Company — 5S mine 198 New Idria coarse-ore furnace 117, 223-225 temperature in 225 '' district — 34, 93, 94-95 formerly in Fresno County 43 geologic map of 94 timber in 95 transportation to 95 mine __— __ 14, 17, 34, 93, 95, 109-115, 236 absorbed quicksilver at 243 air circulation in condensers at 265 associated minerals of 29 barrel condensers at 258 classification in mill of 341 cleaning up condensers at 274 composition of soot 275 concentration at 329, 339-342 cost data -- 119 flotation experiments at 342 flow-sheet of plant at 340 fuel-oil used at — 16 map of 110 metacinnabarite in 95, 112 new assay method at 277 operating data -_ 11^' ore transportation at 113, 116 orebodies of — — 109, 110 power at . 115 production of 109 reduction equipment of — 116-119 revolving furnaces at 24 8-250 rotary drier for concentrates at 255 round-type wooden condensers at 256, 259, 265 sampling at 342 Scott furnace at 234 sewer-pipe flues in condensers at 264 soot mill at 275-276 stone condensers at 256 surface plant of 108 transportation to 114 treatment of concentrates at 342 wood-n condensers at 256. 264 Qu'cksilver Mining Company 107-120 Newland, D. H 361 New Me:cy mine, condensers at 257 Mining and Development Company 44-48 Sonoma mine 191 native mercury in 191 Standa'-d table _— - 332 Nielsen, Niel 303 Nifssn groun 120 Xikitcwka, Russia, quicksilver at 22 North Almaden mine 155, 168 L,ine mine 161 Star minr. 130 Northern Light prospect _ 88 Northev, G. V 210, 330, 357 Norwegian mine, tellurides in 26 Nye Ranch deposit 46 382 INDEX. Page Oak\iIlr mine 80 Oakland mine ~ ]S5 Oat Hill Leasing Company 333 mine 22, 30, 88-90, 292, 293, 294, 296 (.■innabar placers below 82 concentration at 89, 332-335 cost pir flask at 337 ore samples from 286, 287 ores favorable for table concentration ' 299 production of 76 Scott furnace at 234 use of liffles at 334 ■ Occidental and Healdsburg group 192 Occident mine 71 Ochre, effect of, on alkaline sulphide solutions 323, 326 Oceanic district 34 125 mine __ 124, 125, 140-146 concentration at 146, 338-339 cost of s(iuare-set stoping in I44 effect of introducing air into condensers at 266 exti'action at -- 245 notation experiments at 339 fume trap at 241 geology of 142-143 map of 142 mining method in I43 operating costs at 244 production of 142 i-ectangular wooden condensers at ; 260 reduction equipment of 145-146 Scott furnace at 229 soot treatment at 271 sub-level slicing in 143 wooden condensers at 256 developed at 264 Ohly, Dr. J 357 Oil as fuel, effect of, on amount of soot produced 274 as fuel for quicksilver furnaces 16, 49, 118, 166. 185, 189 attached to flotation concentrates 339 crude, as fuel 255 in St. John's mine 177 flotation concentration by 300-320 Oils used in flotation tests 303-305 use of Mohr pipette in measuring 303, 319 Old Cliapman prospect 192 Onofrite 28 Opal 28 Operating costs 14, 60, 131, 144 costs, at Cambria mine 244 at Oceanic mine 244 of Scott furnace 243-245 data for New Idria Company 119 Orange County, (|uicksilver in 92 OriOjodies in St. Jolin's mine 177 of New Idria mine -- 109-112 Ore deposits, age of 18, 21 form of 23-24 dressing, bililiography on 354-358 drier at Klau mine 254 at St. Jolin's mine 179 Socrates mine ^ 194, 195 driers 254-255 sizing at New Idria mine 119 Orestimlja mine 198 Oro y Plata mine — 35 Outline map of California, showing distribution of quicksilver deposits 17 of metallurgy 209-210 Overland group 202 Pacific Foundry Company 217 group 192 Quicksilver Company 44-46 Pack. R. W _-_ 94 Paint, anti-fouling, quicksilver used in 9 'Paint' ore 25. 287, 338 Palisade silver mine, quicksilver in 90 Panning tests for cinnabar 329 Parker. K. W 361 Parklield mine (see also under Patriquin) 73, 292, 293, 295, 296 ore simples from 287 Parson.s, C. S 314, 357 INDEX. 383 Page Patriquin Hrothers 52 -(^Tillott Quicksilver Mining Company 73 Louis 206, 288 mine 73-75 Jolmson-Mi-Kay retort at 214 ore samples from 287 retort condensers at 257, 261 practice at ' 75 Patten c'laims 90 Pattersiin and Western Railroad I97 Peep-hoh's in Scott furnace 231 239 Fenfleld. S. L ' 361 Pensacola Tar and Turpentine Company 304 Percentage of extraction by concentration 352 by concentration at Sulpliur Bank mine 347 Herreschoff furnace 253 Scott furnaces 245-246 Peterson, T. A 288 Petroleum 28 as fuel for quicksilver furnaces ^ 16 crude, for flotation 305, 314, 317 in St. John's mine 177 Pevear furnace 218 Philadelpliia claims 90 Phillips. J. S -- 361 W. B. 357, 361 Phoenix Mines — 198-199 Picachos mine . 105 Picric acid as a fulminate substitute 9 Pine Flat district 181 Mountain district 34, 126 g-roup 126, 146 oils 304-305, 314 Pioneer mine — 181, 193 Pipe retorts 210-215 Pitt mine 73 Pittsburg claim 181 mine 58 Placer recovery of absorbed quicksilver at New Almaden 243 recovery of cinnabar 82, 169, 201, 330, 335 Plan and elevation of concentrating system at Manzanita mine 331 Polar Star mine 147 Pontiac group — __ 193 Pope Valley mine 77 mines 76 Posepn>-, F. 361 Potassium chlorate as a fulminate substitute 9 thiocyanate solution for titration method 279 Power at New Idria mine 115 costs 146 Practical application of the sodium sulphide solution method 323-328 applications of concentration to quicksilver ores in California 329-348 Precious-metal thermo-couple 239 Precipitation of dissolved mercury by aluminum 323, 325 Pi'ices per flask 11, 15 Production cost per flask-- 128, 180, 337, 343 Properties of mercury 208-209 Providential mine 44 Pyrargyiite — 28 Pyrite 28, 29 effect of its presence on roasting 81, 105 in Helen mine ore 290 large crystals of, in Capitola mine 132 selective flotation of, with cinnabar 315 Pyrolusite -- 28 Pyrometer, electric, use of : 342 on Herreschoff furnace 250 recording, use of 118, ISO, 239 Quartz 28, 29 Quaternary age of quicksilver deposits 18 Quicksilver, assays for 277—285 bibliography on assays, chemistry, etc 354-358 on geology of 358-362 deposits, age of 18, 21 ■ .geographical distribution of 17 geology- of 17-24 map showing distribution of. In California 17 relative shallowness of 21 electrolytic deposition of, from solution 328 metallic, recovei-y of, at New Almaden mine 344-345 recovery of, by Senn amalgamator 276 military necessity of 9 384 INDEX. Quicksilver — Continued. Page min3ials 25-29 native, recovery of, by concentration (see also under native mercury) 299, 337 ores, author's experiments on concentration of 286—328 minerals associated with 28—29 practical applications of concentration to, in California 329-348 prices -- 9, 11-12 production (see also under each county) in California, 1850-1917 9-11 properties of 208-209 solubility of, in alkaline sulphide solutions 321 uses of 9 'Quicksilver series' IS Quifn Sabe group 133 Quotations vs. sales 12 Raincr, Roland Sterner- 357 Ral-ston, O. C 300, 319, 357 Ramirez Consolidated mine 105 Randol, J. B 9, 205, 231, 357, 361 Ransome, P. L. -- 35, 203, 361, 362 Rath, G. von 361 Rattlesnake mine __ 181, 192-193 concentration at 337 native mercury in 192 Rav electric oil-burner 185, 227, 229 Raymond, R. W 330, 357, 361 Reactions, chemical, for sulphide solutions 321, 324, 325 Realgar __ 29 Rearden, Phil -- 361 Recording pyrometer, use of — 118, 239, 250 Recovery by Herreschoff furnace 253 Red Cloud claim 192 Elepliant pi-ospect 62 Mountain magnesite district -- 197 R3ck and Silver Rock claims •-_ 62 Reck Quicksilver Mining Company 150 Redingtonite __ 28. S3 Redington mine 76, 82 mi tacinnabarite at 26 Reduction equipment of New Almaden mine 164-167 equipment of New Indria mine 116-119 of Oceanic mine 145-146 of St. John's mine 179-180 of concentrates 350 Reed mine 204, 205 Regulation of air in quicksilver furnaces 240 of draft through condenser system 269 Reis, Heinrich 361 Resume of flotation results 314-320 Retort condensers 255, 257-258, 261, 262 practice at Patriquin mine 75 Retorting of concentrates 331, 332, 336 Retoits 210-220 at Big Injun mine 57 Manzanita mine 210-212 continuous-feed -- 215—220 cost of 1 212 doubtful economy of 215 limited capacity of 215 size of 212 Revolving furnaces 247—254 Rhenisli Bavaiia, Germany 29 Rhynchou (lilt -W hit yiciji 33 Rhyolit '. cinn:il)ar in — 47—48 Richards pulsator-classifler 341 pulsator-rilile 34 5 R. H. 329. 349, 357 Rich Hill prospect 63 Rickard, T. A 357 Riffled launders, use of 332, 333, 334 Riflle unit, steel 334 Rinconada group 124 mine 147 Rising. W. B -- 357 Roasting of concentrates 350 concentrates at New Almaden mine 343 at New Idria mine 342 period in Scott furnace 235 Robbins, H. R 350 Rockers, concentration of cinnabar by 57, 335 Roger.s, A. F 26, 149, 361 Rolland, M. G — 357 Rosenlecher. R. 329, 357 INDEX. 385 Page 247-250 Rotary furnace •. _ 99 100 furnace at Aurora mine - 348 advantages of — ~~"S_~ _l Z__249, 250 size of feed for - 247 ore-drier — , " "^ I94 roaster at Socrates mine ---. - - - ocq 265 Round wooden condensers at New Idria mine --_- — --oJ, .b5 Royal Development Company II~IIII"I " 204 Ru'bv mine — ~ ~ 206, 291 Ruddock, G. T 80. 217 Rutherford Mining Company lyilllllllZI^I I 41 Ryne mine 361 Sachs, A. — 12 Sales vs. quotations 246 Sampling at Idria, Austria - 342 New Idria mine - 286-291 Samples treated by author-- 93-122 San Benito County, mines in — 93 Countv, production of _ 93-96 quicksilver districts m IIIIII__I 103 mine .~r~r, r " 123 San Bernardino County, quicksilver m _- 329 San Carlos mine, early concentration at ""111 115-116 of New Idria Company III__I 34, 126 San Carpojaro district 357 Sand. H. J. S •---t.— -— .- " 124 San Francisco County. quicksiUer m -^^-^ market, quotations on quicksilver -^ -- -^^^ San Jose Valley mine-- IIII~IZ--I"-- ^^^ ll^ £S?^S"coS^m-gi3i;;^aii^oi-qui;^Tvef mstHcts --^-::::::i24-ll^ mines in 127 production of 34 districts — — -— . 127 quicksilver districts, timber in 5^27 transportation to ■ 149 San Mateo County, quicksilver in - 150-153 Santa Barbara County, mines m _- I50 County, production of IIII_I 161 mine, Peru 152 water tunnel — _ 154-170 Santa Clara County, mines m -__- 156 Countv, production of_--- 147 mine (San Luis Obispo County) - I60 mine (Santa Clara County) ""1111111-—- 105,135 Santa Cruz mine — 124 Lucia Range, quicksilver mines m """II 140 Maria mine ^J 131, 132 Monica claim 190 Rita prospect - 152 Rosa mine "_"■ 155, 167 Teresa mine 151 Tnez Quicksilver Company r"IIIII 29 Santander. Spain — ~ 27, 356 Schaller, W. T I'lIII^I 208, 328, 358 Schnabel & Louis — __- 358 Schrauf, A. — 355 Schutte. C. N.— -- .- T4"4rTl,'60, 79. 166, 194, 199, 226, 231-246 "^^"fu^^cras'^a^if^xpTller-Vf-quicksTir^ HI at Klau mine - 229 Oceanic mine 235 automatic charging of ~ ^■_231, 234 capacity of ~" 258-270 condensers for 131, 235, 352 cost of 231 of tiles for 7- — 7" 161 development of, at New Almaden - 45^ 233 discharge of 239-240 fuel consumption in 268-270 fume losses from " 235 insulated walls in " 241-243 losses from . " ' 235 materials for construction of I""I_I 243-245 operating costs of 237 outline sketch of 245-246 percentage of extraction by IIIIII 235 roasting period in 117 small, at New Idria mine- 236-239 temperature distribution m 231 tiles for I~III_ 241 top losses in ~" ~ " 232 top of 25—38540 'AS6 INDEX. Page Scott, Robert 209, 231, 261, 358 Screen analyses of ores tested 292, 293 summary of 293 Soal for furnace-top fumes 225, 241 Seamon, W. A 358 Secretary of War 3(52 Selective flotation of pyrite with cinnabar 315 Selenide of niei'c ury 27, 193 Senator mine of New Almaden company 161, 164 automatic cliarging of new Scott furnace at 235 notation at 344 I len-esclioff furnace at 250-253 I.iLiKlers I'etort at 217 Senn pan-motion amalgamator 275, 276, 299 Serpentine 28 associated witli quicl ]o:v] Mturm «ci uiiRA«x LIBRARY, UNIVERSITY OF CALIFORNIA, DAVIS J?(iok Sliii— Si-rics 458 m ^ ^ '^^^^ JM4 5 1994 RECEIVED JUN 3 n \m PHYSICAL SCS.LlBRARy HFCEIVED HAR 1 i\ 2' :!3 PSl 3 1175 00464 Tzse 24 C3 ..-78 PHYSICAL SCIENCES LIBRARY 9^579 California. Division of .V;inT?s dp. Bulletin.