J Physical! ^CI.LlBi NO. 141 STATE OF CALIFORNIA DEPARTMENT OF NATURAL RESOURCES GEOLOGIC GUIDEBOOK ALONG HIGHWAY 49— SIERRAN GOLD BELT BULLETIN 141 THE MOTHER LODE COUNTRY (CENTENNIAL EDITION) 1948 DIVISION OF MINES FERRY BUILDING, SAN FRANCISCO EX LIBRIS C Osborne Htitton -eU DEPARTMENT OF NATURAL RESOURCES WARREN T. HANNUM, Dirmlor STATE OF CALIFORNIA EARL WARREN, Govgrnor DIVISION OF MINES Ferry Building, San Froncisco 11 OLAF r. JENKINS, CW.f San Francisco] BULLETIN 141 [September, 1948 GEOLOGIC GUIDEBOOK ALONG HIGHWAY 49—SIERRAN GOLD BELT THE MOTHER LODE COUNTRY (CENTENNIAL EDITION) Prepared under the direction of OLAF P. JENKINS CHARLES V.AVERILL OLIVER E. BOWEN, JR. JOHN A. BURGESS Confribufing Authors RICHARD A. CRIPPEN, JR. DONALD C.CUnER FRANKLIN FENENGA ROBERT F. HEIZER DOROTHY G. JENKINS OLAF P. JENKINS CLARENCE A. LOGAN ^ l>lVISln\ (IF MIXKS l'.ri.I.i:-l'IX 141. I'l.ATK 1 A, LOOKING NORTHEAST TOWARD HARRY L. EXGLEBRIGHT HAM Structure wns tU'dicated to the memory of Harry Ij. Englebright. menther of Cougri'ss, lD2li-43, by the California Hydraulic iliuers Association and approved by act of Conjrress in November 194"!. This (him is one of several constructed for the dual purpose of catching debris from upstream hydraulic oi)eratious and imijounding water for irrigation. Photo hy courtesy of George TT. JlaUock, Stale Aliiiiiuj Boiiiil. It, LOOKING NORTHEAST TOWARD MALAKOFF HrDRAULIC PIT AT NORTH BLOOJIFIELD. NEVADA COUNTY. Photo hy courtesy of Geortje W. Ilallock l>IVISI(i\ OF MIXKS BUIJ.ETIX 141. I'LATI-] '2 A. I'A\i:" Prominent qmirtz outcrojis of the Mother Lode system a.s seen nt the Harvard mine near .lamest. iwn. Phufo hi/ Ohif P. Jenkins. V, ■TU.MUSTOXK RUCK- ( H" \'()L('A\IC AOiiLOMERATE Occurs one mile west of ( 'oii(iero]nilis on the Farraington mad. Pholo In, Ohif P. Jrnkins. D, SilALL AXTK.'EINE IX KLATE ALOXG MARirOSA CREEK Folds are along actual slate beds and not alons slnly cleavage lines. Photo hij Oluf P. Jenldns. E, TYPICAL VIEW OF THE SIERRAX FOOTHILLS Xear Mount Gaines mine. Hornitos district, ^Iariin>sa Counly. Phoio hy coKriesi/ of Francis Frvdcrick. F, rXDERGROFXD VIEW In Alhambra mine near Garden Valley, El l>orado County. Xote the free gold showing in jialches in white quartz. Photo hy courteitij of Francis Frederick. - --^JJi^^gjJlM K W^iMidJ-- - LETTER OF TRANSMITTAL To His Excellencxi The Honorable Earl Warren Governor of the State of California Dear Sir: I have the honor to transmit herewith Bulletin 141, "Geologic Guidebook Along Highway 49— Sierran Gold Belt", prepared under the direction of Olaf P. Jenkins, Chief of the Division of Mines. The volume contains a series of geologic maps covering the entire highway, a strip of country 277 miles in length. Numerous photographs and other illustrations accompany the articles which make up this bulletin. The book represents the Centennial Edition of the Division of Mines, describing The Mother Lode Country. It has been carefully compiled from vari- ous publFshed and unpublished sources of information supplemented by notes taken during field investigations carried on particularly for this volume. Besides the ten different authors who have written the chapters of this bulletin, a score of other mining men and geologists have contributed information. Bulletin 141 is a semi-technical treatise prepared to serve as a guide to the traveler who is desirous of information concerning the mines, minerals, and rocks of the region, as well as the old structures erected during the Gold Rush Days. It is not merely intended for use during the Centennial celebrations, but should serve as a basis for future studies and investigations for many years to come. Respectfully submitted. Warren T. Hannum Director, Department of Natural Resources August 1, 1948 CONTENTS Page Preface, by Olaf P. Jenkins ^ Publications Consulted 8 Sierran Roads of Today and Yesterday, by Dorothy G. Jenkins 9 The Discovery of Gold in California, by Donald C. Cutter 13 History of Placer Mining for Gold in California, by Charles V. Averill 19 Sierra Nevada Province, by Olaf P. Jenkins 21 Geologic History of the Sierran Gold Belt, by Olaf P. Jenkins 23 History of Mining and Milling Methods in California, by C. A. Logan 31 Geologic Maps and Notes Along Highway 49, by Oliver E. Boicen Jr. and Richard A. Crippen Jr 35 The Formation of Quartz Veins, by John A. Burgess 87 Mining on Carson Hill, hy John A. Burgess 89 Survey of Building Structures of the Sierran Gold Belt, 1848-70, by Robert F. Heizer and Franklin Fenenga 91 o i PREFACE The Centennial Celebration of the discovery of jrold at Coloma by James W. Marshall on January 24, 1848, has stimulated renewed interest in the Mother Lode of California and has brought forth a number of new books, pamphlets and stories of the early pioneer days. Most of this literature has to do with the historj-. life, and romance of the Gold Rush period which vividly stamped upon the new western state a per- sonality which has by no means been erased durin- Building, San Francisco Mav 10, 1948 Olaf p. Jenkins Chief, Division of Mines (7) GEOLOGIC GUIDEBOOK ALONG HIGHWAY 49 [Bull. 141 PUBLICATIONS CONSULTED General Historical Interest Bailev, Pai"L D.. Rnm Brannan and the Mormons: Westernlore Press, 187 pp., Los Angeles, 1943. B.\XCROFT. Henry H.. History of r'alifornia : A. L. Bancroft and Co. and The History Co.. 7 vols., San Francisco, 1884-1800. Clelaxd, Rohert O., A history of California, the American period : The JIacMillan Co.. .-|12 pp.. New York, 1922. Dri'RY, Avbrey. California, an intimate guide: Harper and Bros., .">92 pp.. New York, 1947. Glasscock, C. B.. A golden highway : The Bobbs-Merrill Co., 313 pp., Indianapolis, 1934. Hint. Rockwell P., California the golden : Silver, Burdette and Co.. 3G2 pp.. New Y'ork and Boston. 1911. Rexsch, H. E., Hoover, Mildred Brooke, and others. Historic spots in California, valley and Sierran counties: Stanford Univ. Press and Cambridge Univ. Press, 368 pp., Palo Alto and Cambridge, 1933. Roberts. Brigham H., The Mormon battalion : Deseret News, 96 pp.. Salt Lake Citv, 1919. Westox, Otheto, Mother Lode album : Stanford Cniv. Press, 177 pp.. 2 pis., 204 photos, Palo Alto, 1948. The Gold Rush Period Lekeart, Phillip B., ,Tanies W. Marshall, discoverer of gold : Soc. California Pioneers Quarterly, vol, 1, no. 3, pp. 3-43, San Francisco, September 1924. r.ORTHWicK, ,1. D., Three years in California : W. Blackwood and Sons, 384 pp., Edin- burgh and London, 18,">7. Reprinted 1917 as The Gold Hunters edited by Horace Kephart : i.tuting Pub. Co., Cleveland and New York. P.rCKBEE, Ed.\a B., The saga of old Tuolumne : R. R. Wilson, 326 pp,, Xew Y'ork, 1933. BfFFfM, E. wnieville folio (no. 37), 10 pp.. 4 maps, 1 pi., 1897. Turner, H. W., U. S. Geol. Survey Atlas, ,Tackson folio (no. 11), 8 pp., 4 maps, 1.894. Turner, H. W., and Lindgren. Waldemar, U, S. Geol, Survey Atlas, Smartsville folio (no. 18), 8 pp., 4 maps, 1893. Turner, H. W.. and Rax.so.\ie, F. L., U. S. Geol. Survey Atlas, Big Trees folio (no. 31), 10 pp.. 3 maps, 1 pi., 1898. Turner. F. W., and Ran.some. F. L., U. S. Geol. Survey Atlas, Sonora fidio (no. 41), 9 pp.. 4 maps. 1897. SIERRAN ROADS OF TODAY AND YESTERDAY !'•: ItoROTllY (J. .TkNKINS Hiiiint>iit. Tlii.-* iiiflurt' \v;t.s IiroliMlilv tjikeu in ls-"i:l. Tin- iimii in III.- Inri-Kniuiicl i.'* siii.|">--^".. Sam nrjiniiiin ami the .Mnrni'ms : \Ve^ti.rtiltu.«' I'res^. \s~ i.p.. Los Ansele.^i. 194.3. l'..^XCBOFT. He\ry H.. Ilistor.v rit California : A. L. Baiur.ift an>l <'•.. anil Tllf Hi^^tcir.l' Co., T vol.s.. San Francisco. 1X84-1890. FiEKE-VRT, Phillip B.. .lames AV. Marshall, discoverer of ;:oI(l ; Sue. California I'ioneers Quarterly, vol. 1. no. .S. pii. .^-4.'^. .San Francisco. Se[iienilier llni4. K^"FFl"^r. E. (Jocld. .six months in the gold mines: Richard Rentlev. 244 pp.. London. 1.«.-jO. Cknkrars. Iil..\lSE. Sutters ;;old ; Harper and Bros.. 179 i>p.. Xew York and London, 192tJ. Translated from the French li.v Henry L. Stuart. Clel.\xd. Robert (I.. A historv of California, the American jieriod ; The MacMillan Co., 512 pp., Xew York, 1922. Cov. Owex C, Gold days: PoweU Pub. Co.. .3.S1 pp.. Los Anceles. 1929 (19.-i4l. It.\X-\. JVLl.^x, Sutter of California: Halcvon Press (Blue Rihiton B'loks. Inc. I. 41.3 pp., Xew York. 19S4. HfLBERT. Archer B.. Forty-niners; Little. Brown an. .\ppleton- Centnry Co.. Inc.. .~i06 pp.. Xew Y'ork and London. 19:-lti. RiCK.VRI). Thom.\s a.. The discovery of gold in California: T"niversity vs. 90 pp.. Salt Ijike Citv. 1919. ^VHITE. StEW.\rt Kdw.\ri). The fortv-niners : Vale Cniv. Pre.ss. 27.3 pp.. Xew Haven. 1918. 18 GEOLOGIC GUIDEBOOK ALONG HIGHWAY 49 [Bull. 141 :.^2>,i?dfr:L' Fig. 1. Omega hydraulic mine; the large water pipe supplied the "giants" or hose Fio. 3. View southwest toward Hlue Tent ditch, a typical (.ariier of waler supplying nozzles. Photo by Olaf P. Jenkins. the hydraulic diggings. Photo htj Olaf P. Jenkins. -^'■>>-- Fig. 2. Ifepot Hill liydruulie mine near Ciiniptonviile. Fig. 4. View southwest toward placer mine half a mile east of Downieville. HISTORY OF PLACER MINING By Charles V Methods for the recovery of gold even today depend largely on the high specific gravity of that metal. A particle of gold of a certain size is so much heavier than a particle of associated rock of the same or even larger size, that a current of water washes the particles of dirt and rock away and leaves the gold behind. At Sutter's sawmill, water turned through the ditch to operate the water wheel washed away the dirt and gravel and left the bright flakes of gold. These were caught on the rough bottom of one of the ditches where Marshall found them. The earliest efforts to recover gold, after Marshall's discovery, were directed toward those places where flakes and nuggets of gold had been concentrated on rough bedrock and in crevices by the natural flow of the streams. Small tools were used to dig in the crevices and to pick up the flakes of gold. Soon the miner's pan came into u.se. An ordinary frying pan can be used to concentrate gold providing it is free of grease, but the familiar miner 's pan with gently sloping sides is more efficient. It is a simple device for washing away the lighter dirt and fine gravel, and concentrating the heavy gold in the bottom of the pan. The capacity of the pan is so limited that gravel very rich in gold is needed to pay by this method. A skilled operator is able to pan less than one cubic yard of gravel during a day's work. The batea is a wooden version of the miner's pan that was introduced into California at a very early date by Mexican miners. Rockers or cradles and sluice boxes were the next devices used by the early -day miners. The rocker is a crude concentrating machine made of wood that combines the shaking motion of the pan with some of the features of the sluice. Riffles or obstructions are placed across the bottom to catch the heavy flakes of gold. The dirt and gravel are washed over the tops of the riffles. With the rocker, both the gravel and the water are introduced by hand. With the sluice, the water flows by gravity, but the gravel is shoveled in by hand. The miner is able to wash several cubic yards per day — still a small amount of gravel. By 1860, gravel that would pay to work by these methods was getting hard to find, and production of gold declined. In the meantime the hydraulic method of mining was developed. Great jets of water were directed against banks of gravel hundreds of feet in height. Some of the jets of water were 9 inches in diameter as they left the nozzles. After the proper ditches and pipe lines had been installed, thousands of cubic yards of gravel could be washed without hand labor. The gold was recovered in riffle-sluices, and quicksilver was usually added to aid in its recovery. The debris deposited in streams by hydraulic miners became so objectionable to agricultural interests that the method was stopped by injunction in 1884, and placer production dropped to a very low level. Evidence of hydraulic mining in the form of old gravel banks may be seen on Highway 49 at Mokelumne Hill in Calaveras County and (19) FOR GOLD IN CALIFORNIA . .\VERILL near Camptonville in Yuba County near the Sierra County line. The Depot Hill mine near Camptonville has been worked quite recently. The Bullard Bar dam of the Pacific Gas and Electric Company is avail- able for the .storage of tailings; hence this mine can be operated legally at the present time. Other dams that were constructed primarily for the purpose of restraining such tailings are located on the North Fork American River about two miles above its confluence with Middle Fork American River near Auburn, and on the Yuba River about li miles above its confluence with Deer Creek near Smartsville. Some of the largest hydraulic mines ever operated are a few miles east of Xorth San Juan. Leaving Highway 49 at this point, one may travel for 1.3 miles practically along the course of an ancient river channel in which gold-bearing gravel was deposited many millions of years ago to a depth of about .300 feet. The climate was semi-tropical at that time, and the elevation was much lower. The region has been raised by tilting so that the bed of the ancient river now occupies the top of a high ridge. The largest mine was the ilalakoff at Xorth Bloomfield, and it was the injunc- tion against this mine in 1884 that practically put a stop to hydraulic mining in this region. The lode mines with their ipiartz veins and stamp mills took over the major output of gold, and the prodiu-tion curve rises gradually until about 1!)()0 when connected-bucket dredges were introduced and made the curve rise a little faster. These great niacliiues contain a continuous chain of buckets for digging the gravel and taking it aboard the floating barge. Such a chain of buckets and tlie support for it (the ladder) may weigh 1.000 tons. The entire outfit including the digging machinery and the equipment for washing out the gold may weigh 8.750 tons. Riffle sluices and quicksilver are still used to rei-over the gold on the dredges, but sluices are gradually being replaced by jigs, which are mechanical devices for concentrating the gold. The dragline t.vpe of dredge is a later develop- ment that was introduced in the 19;!0's. The heavy iligging equipment is an ordinary dragline excavator tliat travels on the bank. The floating barge carries only the screen, equipment for concentrating the gold, and the tailing-stacker. Placer gravel is haiidled so cheaply on these dredges that gravel running 10 cents to 20 cents per cubic yard can be mined at a profit. Inflation foMowing World War I stopped the rising trend of gold production, and it declined until the early 1930 "s, when the increase in price from $20.67 to .tS.] per fine ounce caused production to rise initil 1940. In October 1942 Limitation Order L-208 of the War Production Board stopped all gold mining with few exceptions. This caused great damage to California mines in the form of flooded and caved workings, and gold production is now at a very low level. It cannot be expected to rise very fast under present conditions of high costs of labor and supplies, unless a way can be found so that the miner will receive more than !|C55 per fine ounce for his gold. The price is higher than this in many countries today. 20 GEOLOGIC GUIDEBOOK ALONG HIGHWAY 49 [Bull. 141 GEOLOGIC MAP OF CALIFORNIA AJOR ROCK UNITS nozoic volcanici noioic sedimertH f+aceoui ledtmentj rossic Francijcan qroup soioic - Poleoioic tqmorphic - qranidc rocks iin~Ranqes and Mo]Ow« Ocierl :k-co'npleK Syncltne Pleij*ocer« fauH- Fig. 5. Geologic map of California showing major rock units. Reprinted from California Div. Mines Repi. J/O, pi. 8. Fig. 6. .4, Block diagram illustrating Cretaceous Sierra Nevada topography. The upturned edges of bedrock controlled the drainage pattern, which was later inherited by streams of the early Eocene period. After Matthes, U. S. Oeol. Survey, Prof. Paper 160. J930. B, Block diagram to show tilting of the Sierra Nevada and its effect on stream cutting. P>osion, prior to the tilting, planed down the surface and exposed the granite, leaving only occasional fragments of the intruded metamorphic rock-bodies as roof pendants. The streams, at the point where they leave th.eir mountain canyons and enter the Great Valley, form alluvial fans. After Matthes. V.