iwju ^ 4 '5; ■ STATE OF CALIFORNIA DEPARTMENT OF NATURAL RESOURCES RADIOACTIVE DEPOSITS IN CALIFORNIA SPECIAL REPORT 49 DIVISION OF MINES FERRY BUILDING, SAN FRANCISCO SPECIAL REPORTS ISSUED BY THE DIVISION OF MINES l-A. Sierra Blanca limestone in Santa Barbara County, Cali- fornia, by George W. Walker. 1950. 5 pp., 1 pi. Price 25 *. 1-B. The Calera limestone, San Mateo and Santa Clara Counties, California, by George W. Walker. 1950. 8 pp., 1 pi., 6 figs. Price 25 *. 2. Geology of part of the Delta-Mendota Canal near Tracy, Cali- fornia, by Parry Reiche. 1950. 12 pp., 5 figs. Price 25*. 3. Commercial "black granite" of San Diego County, California, by Richard A. Hoppin and L. A. Norman, Jr. 1950. 19 pp., 18 figs. Price 25*. 4. Geology of the San Dieguito pyrophyllite area, San Diego County, California, by Richard H. Jahns and John F. Lance. 1950. 32 pp., 2 pis., 21 figs. Price 50*. 5. Geology of the Jurupa Mountains, San Bernardino and River- side Counties, California, by Edward M. MacKevett. 1951. 14 pp., 1 pi., 14 figs. Price 250. 6. Geology of Bitterwater Creek area, Kern County, California, by Henry H. Heikkila and George M. MacLeod. 1951. 21 pp., 2 pis., 15 figs. Price 35*. 7-A. Gem- and lithium-bearing pegmatites of the Pala district, San Diego County, California, by Richard H. Jahns and Lauren A. Wright. 1951. 72 pp., 13 pis., 35 figs. Price $2.50. 7-B. Economic geology of the Rincon pegmatites, San Diego County, California, by John B. Hanley. 1951. 24 pp., 1 pi., 5 figs. Price 35*. 8. Talc deposits of steatite grade, Inyo County, California, by Ben M. Page. 1951. 35 pp., 11 pis., 25 figs. Price 85*. 9. Type Moreno formation and overlying Eocene strata on the west side of the San Joaquin Valley, Fresno and Merced Counties, California, by Max B. Payne. 1951. 29 pp., 5 pis., 11 figs. Price 60*. 10-A. Nephrite jade and associated rocks of the Cape San Martin region, Monterey County, California, by Richard A. Crippen, Jr. 2d printing. 1951. 14 pp., 14 figs. Price 25 *. 10-B. Nephrite in Marin County, California, by Charles W. Chester- man. 1951. 11 pp., 16 figs. Price 25 *. 10-C. Jadeite of San Benito County, California, by H. S. Yoder and C. W. Chesterman. 1951. 8 pp., 6 figs. Price 25*. 11. Guide to the geology of Pfeiffer-Big Sur State Park, Monterey County, California, by Gordon B. Oakeshott. 1951. 16 pp., 1 pi., 28 figs. Price 25*. 12. Hydraulic filling in metal mines, by William E. Lightfoot. 1951. 28 pp., 15 figs. Price 50*. 13. Geology of the saline deposits of Bristol Dry Lake, San Ber- nardino County, California, by Hoyt S. Gale. 1951. 24 pp., 1 pi., 2 figs. Price 35*. 14. Geology of the massive sulfide deposits at Iron Mountain, Shasta County, California, by A. R. Kinkel, Jr., and J. P. Albers. 1951. 19 pp., 6 pis., 6 figs. Price 75*. 15. Photogeologic interpretation using photogrammetric dip cal- culations, by D. H. Elliott. 1952. 21 pp., 9 figs. Price 50*. 16. Geology of the Shasta King mine, Shasta County, California, by A. R. Kinkel, Jr., and Wayne E. Hall. 1951. 11 pp., 3 pis., 4 figs. Price 50*. 17. Suggestions for exploration at New Almaden quicksilver mine, California, by Edgar H. Bailey. 1952. 4 pp., 1 pi. Price 25*. 18. Geology of the Whittier-La Habra area, Los Angeles County, California, by Charles J. Kundert. 1952. 22 pp., 3 pis., 19 figs. Price 50*. 19. Geology and ceramic properties of the lone formation, Buena Vista area, Amador County, California, by Joseph A. Pask and Mort D. Turner. 1952. 39 pp., 4 pis., 24 figs. Price 750. 20. Geology of the Superior talc area, Death Valley, California, by Lauren A. Wright. 1952. 22 pp., 1 pi., 15 figs. Price 500. 21. Geology of Burruel Ridge, northwestern Santa Ana Moun- tains, California, by James F. Richmond. 1952. 1 pi., 11 figs. Price 50*. 22. Geology of Las Trampas Ridge, Berkeley Hills, California, by Cornelius K. Ham. 1952. 26 pp., 2 pis., 20 figs. Price 75*. 23. Exploratory wells drilled outside of oil and gas fields in Cali- fornia to December 31, 1950, by Gordon B. Oakeshott, Lewis T. Braun, Charles W. Jennings, and Ruth Wells. 1952. 77 pp., 1 pi., map. Price, map and report, 75* ; map alone, 50*. 24. Geology of the Lebec quadrangle, California, by John C. Crowell. 1952. 23 pp., 2 pis., 10 figs. Price 750. 25. Rocks and structure of the Quartz Spring area, n Panamint Range, California, by James F. McAlliste' 38 pp., 3 pis., 13 figs. Price 75*. 26. Geology of the southern Ridge Basin, Los Angeles < California, by Peter Dehlinger. 1952. 11 pp., 1 pi Price 50*. 27. Alkali-aggregate reaction in California concrete aggi by Richard Merriam. 1953. 10 pp., 12 figs. Price 35*. 28. Geology of the Mammoth mine, Shasta County, Califoi A. R. Kinkel, Jr., and Wayne E. Hall. 1952. 15 pp., S figs. Price 75*. 29. Geology and ore deposits of the Afterthought mine, County, California, by John P. Albers. 1953. 18 pp., 9 figs. Price 75*. 30. Geology of the southern part of the Quail quadrangle fornia, by Charles W. Jennings. 1953. 18 pp., 2 pis., Price 75*. 31. Geology of the Johnston Grade area, San Bernardino C California, by Robert Barton Guillou. 1953. 18 pp., 1 figs. Price 75*. 32. Geological investigations of strontium deposits in so California, by Cordell Durrell. 1953. 48 pp., 9 pis., ] Price $1.25. 33. Geology of the Griffith Park area, Los Angeles Countj fornia, by George J. Neuerberg. 1953. 29 pp., 1 pi., 1 Price 50*. 34. Geology of the Santa Rosa lead mine, Inyo County, C nia, by Edward M. Mackevett. 1953. 9 pp., 2 pis., Price 50*. 35. Tungsten deposits of Madera, Fresno, and Tulare Co California, by Konrad B. Krauskopf. 1953. 83 pp., 4 i figs. Price $1.25. 36. Geology of the Palen Mountains gypsum deposit, Ri' County, California, by Richard A. Hoppin. 1954. 25 pi., 32 figs., frontis. Price 75* 37. Rosamond uranium prospect, Kern County, Califorr George W. Walker. 1953. 8 pp., 5 figs. Out of print. 38. Geology of the Silver Lake talc deposits, San Bern; County, California, by Lauren A. Wright. 1954. 3 4 pis., 18 figs. Price $1.00. 39. Barite deposits near Barstow, San Bernardino C California, by Cordell Durrell. 1954. 8 pp., 4 pis Price 50*. 40. Geology and mineral deposits of the Calaveritas quadr Calaveras County, California, by Lorin D. Clark. 19! pp., 2 pis., 6 figs. Price $1.75. 41. Geology and mineral deposits of the Angels Camp ar nora quadrangles, Calaveras and Tuolumne Counties, fornia, by John H. Eric, Arvid A. Stromquist, and C. J Swinney. 1955. 55 pp., 4 pis., 21 figs. Price $3.75. 42. Geology and mineral deposits in the Ubehebe Peak rangle, Inyo County, California, by James F. McAl 1955. 64 pp., 3 pis., 26 figs. Price $2.00. 43. Geology of a portion of the Elsinore fault zone, Calif by John F. Mann, Jr. 1955. 22 pp., 2 pis., 5 figs. Pric 44. Bibliography of marine geology and oceanography, Ci nia Coast, by Richard D. Terry. 146 pp., 2 figs. Prici 45. Exploratory wells drilled outside of oil and gas fiel California to December 31, 1953, by Charles W. Jen and Earl W. Hart. 46. Geology of the Huntington Lake area, Fresno Cc California, by Warren B. Hamilton. 47. Economic geology of the Bishop tungsten district, Ct nia, by Paul C. Bateman, with a section on the Pine ' mine, by Paul C. Bateman and Lawson A. Wright. 48. Economic geology of the Casa Diablo Mountain quadn California, by C. Dean Rinehart and Donald C. Ross. 49. Radioactive deposits in California, by George W. W; Tom G. Lovering, and Hal G. Stephens. 1956. 38 pp., ( Price 50*. STATE OF CALIFORNIA GOODWIN I. KNIGHT, Governor DEPARTMENT OF NATURAL RESOURCES DeWITT NELSON. Director DIVISION OF MINES FERRY BUILDING, SAN FRANCISCO 11 OLAF P. JENKINS, Chief ? RANCISCO SPECIAL REPORT 49 JANUARY 1956 RADIOACTIVE DEPOSITS IN CALIFORNIA By GEORGE W. WALKER, TOM G. LOVERING, and HAL G. STEPHENS Geological Survey, U. S. Department of the Interior Price 50^ RADIOACTIVE DEPOSITS IN CALIFORNIA By George W. Walker^ Tom G. Lovering 1 and Hal G. Stephens ** OUTLINE OF REPORT Page iction 3 ctive deposits 4 iuin deposits 4 ium deposits 7 tions for prospecting for uranium and thorium 8 lie evaluation 8 )tion of the radioactive deposits 8 ve Desert province 8 ;-a Nevada province 27 it Ranges province 32 in and Range province 34 . r reported occurrences of uranium and thorium minerals 37 ■itire cited 38 Illustrations 1. Location of radioactive deposits in California exam- ined by geologists of the U. S. Geological Survey and the U. S. Atomic Energy Commission during the period 1948-54 2. Geologic map of vicinity of Section 10 anomaly, Mo- jave mining district, Kern County, California 16 3. Chilson prospect, Kern County, California 18 4. Plan of No. 5 tunnel, Miracle mine, Kern River Canyon area, Kern County, California 20 5. Plan of Kergon No. 1 adit, Kergon group, Kern River Canyon area, Kern County, California 30 6. Embree property, Erskine Creek area, Kern County, California 32 ABSTRACT onnaissance examination of many areas, mine properties, and Jets in California during the period between 1948 and 1954 • logists of the U. S. Geological Survey and the U. S. Atomic k Commission has confirmed the presence of radioactive ma- in place at more than 92 localities. Abnormally high radio- ly at these localities may be caused by concentrations of y or secondary uranium minerals, radon gas, radium, or n minerals. Of the known radioactive deposits, only 8 are t to contain uranium oxide (uraninite or pitchblende), 4 a uranium-bearing niobate, tantalate, or titanate minerals, tain secondary uranium minerals, such as autunite, carno- ad torbernite, 3 contain radon gas, 11 contain thorium niate- ^and, at the remaining localities, the source of the anomalous ion was not determined. nium oxide has been tentatively identified at the Rathgeb ■ (Calaveras County), the Embree property (Kern County), >rih group of claims and the Thum Bum claim (San Bernar- I'ounty), and the Rainbow claim (Madera County). Second- anium minerals are largely confined to the arid desert regions :tern and southeastern California including deposits in Lassen, Bernardino, Kern, Inyo, and Imperial Counties, although 1 important deposits, including the Miracle mine, are in the •rn Sierra Nevada near Miracle Hot Springs in northern County. Uranium-bearing (niobate), tantalate, or titanate als have been reported from pegmatitic and granitic rock in ?astern and eastern California. >rium minerals have been found in vein deposits in eastern Bernardino County and in pegmatites and granitic rocks in is parts of southeastern California ; placer concentrations of im minerals are known from nearly all areas in the state that iderlain, in part, by granitic rocks. : primary uranium minerals occur principally as minute •ory crystals in pegmatites or granitic rock, or with base-metal e minerals in veins. Thorium minerals also occur as accessory ils in granitic rock, in placer deposits derived from such rock, it Mountain Pass in veins containing rare-earth minerals. blication authorized by the Director, U. S. Geological Survey ^nis report concerns work done on behalf of the U. S. Atomic ; nergy Commission and is published with permission of the ^ommission. 3. Geological Survey, Denver, Colorado. S. Geological Survey, Menlo Park, California. Secondary uranium minerals have been found as fracture coatings and as disseminations in various types of wall rock, particularly in areas of Tertiary volcanic rocks. The uranium deposits in Califor- nia probably are related genetically to felsic crystalline and felsic volcanic rocks ; the distribution of the secondary uranium minerals has been controlled, in part, by circulating ground waters and probably, in part, by magmatic waters related to the Tertiary volcanic activity. The thorium minerals are genetically related to the intrusion of granitic rocks. Only one of the uranium deposits in California, the Miracle mine, has shipped as much as a carload of commercial grade uranium ore as of December 1954. The commercial production of thorium minerals probably will be possible only if these minerals can be recovered cheaply as a by-product either from the mining of rare-earth minerals at Mountain Pass or from the placer mining for gold. INTRODUCTION Since 1948, a large number of mine properties, pros- pects, placer deposits, and claims have been examined for anomalous radioactivity by geologists of the U. S. Geological Survey and the U. S. Atomic Energy Com- mission. In addition, collections of ore and rock speci- mens from many other properties have been tested for radioactivity, and many hundreds of miles of traverses have been made by automobile, particularly in the Mo- jave Desert region. The tests of ore and rock specimens and the traverses by automobile have been largely un- successful in finding new occurrences of radioactive ma- terial. Examination of mine properties, prospects, placer deposits, and claims has, on the other hand, confirmed the presence of radioactive minerals at more than 92 different localities in California. This report briefly describes the deposits of radio- active minerals in California. Where the information is available, the location, ownership, development, geology, mode of occurrence, and grade of samples are described for each deposit that was examined prior to December 31, 1954. Much of the field work has been of a reconnais- sance nature ; therefore, detailed information concerning many of the deposits is lacking. A few radioactive de- posits, because of their scientific or possible economic significance, have been studied in more detail. This report is based largely on field investigations of radioactive material in California made by the U. S. Geological Survey and the U. S. Atomic Energy Com- mission between 1948 and 1954. Part of the information has been obtained from published references, and part of the information is from data obtained by C. W. Chesterman of the California Division of Mines; by F. H. Main, F. M. Chace, R. TJ. King, D. F. Hewett, W. N. Sharp, D. R. Shawe, and D. G. Wyant of the TJ. S. Geological Survey ; and by E. E. Thurlow, C. C. Towle, Jr., D. L. Everhart, W. A. Bowes, and H. E. Nelson of the U. S. Atomic Energy Commission. Most of the properties described in the report have been examined by the writers. Most of the field work and the preparation of this report was done by the U. S. Geological Survey on behalf of the Division of Raw Materials of the U. S. Atomic Energy Commission. Chemical analyses for the uranium content of samples collected by the U. S. Geological Survey were made by the Denver and Washington, D. C, laboratories of the (3) Special Report 49 Table 1. Radioactive minerals reported from California. Name Chemical composition ■ Uranium » (percent) Thorium a (percent) Megascopic appearance Locality Allani te Autunite (meta-autunite I has 2H-6HH2O) Betafite(?) Brannerite Carnotite Cyrtolite Davidite Euxenite "Gummite" Monazite Metazeunerite Pitchblende(?) (Massive form of uraninite) Samarskite Thorite Torbernite (meta-torbernite has 8H 2 0) Uraconite(?) (obsolete) Uraninite Xenotime Yttrocrasite(?)_ Zircon (Ca, Ce, Th) 2 (Al, Fe, Mg), Si 3 0i 2 (0H) Ca(UO 2 ) 2 (PO4) 2 10-12H 2 O (U, Ca)(Nb, Ta, Ti) 3 9 nH 2 (U, Ca, Fe. Y, Th) 3 Ti 6 0,6? K 2 (UO 2 ) 2 (VO0s3H 2 O ZrSiO-4-U, Y, Th, and R. E. Near FeKFe>,Ce) 2 Tie0i7-R.E. and U0 2 (Y,Ca,Ce,U,Th) (Nb.Ta.Ti) 2 0. Variable (Ce.La,Th)PO« Cu(UO.)»(AsO-4) 2 -8H 2 Between U0 2 and UjOs (Y,Ce,U,Ca,Fe,Pb,Th) (Nb,Ta,Ti,Sn) 2 0» ThSiO. Cu(U0 2 ) 2 (P0«) 2 8-12H 2 Uranium sulfate UOj YPO4 (Y,Th,U,Ca) 2 Ti«Oii? ZrSiOi 0.02 45-48 16.3-24.5 39.3 52.8-55.0 <1.4 4.4 3-9 40-80? 46.4 55-83 8.4-16.1 <9 47.1-50.8 <88 <3.6 2.3 <2.7? <3.2 1.0-1.1 3.6 ? 0.12 <4.3 ? <26.4 <3.7 25-63 <44 <2.2 7.7 <13.1? Prismatic, orange-brown to black crystals Yellow-green, fluorescent, tabular crystals Green-brown, brittle isometric crystals Brownish-black prismatic crystals Lemon yellow, locally micaceous, powdery Transparent, reddish tetragonal crystals Black, opaque anhedral grains and hexagonal plates Black prismatic crystals Red, waxy, brittle Yellow, red, brown, transparent crystals, commonly tabular Grass green, commonly tabular crystals Black pitchy masses, powdery Black, dull, prismatic crystals Black-brown, glassy isometric crystals — Uranoan variety round green grains Green tabular crystals Black, acicular, or cubic crystals White, brown red, resinous, tetrag- onal crystals Black tabular crystals Translucent, colorless or yellowish, prismatic crystals Rock Corral, Yosemite Park. Miracle mine, Verdi '. property, Chilson pro[ 7, Hoerner-Ross property Mono County near Cole Vanuray and Lucky Sti 1 Kramer Hill Hoerner-Ross property ' Sierra Nevada near Bish j Rock Corral area Jumpin claim, Rosamonc pq Live Oak Tank are I Corral area Truckee Canyon group, m County, Perry Jone: Id Plumas County Yerih group, Rainbow ct I Rock Corral area Mountain Pass area Sierr. m Chilson prospect, Luc j claim? Perry Jones gro Rathgeb mine Rathgeb mine, Breckenrk I tain area, Kern Countj , Live Oak Tank area Riverside Co. (see Mure Webb, 1948, p. 318) Rock Corral area •Frondel and Fleisher (1952). Geochemistry and Petrology Branch, of the Geological Survey. This work was also done on behalf of the Divi- sion of Raw Materials of the U. S. Atomic Energy Commission. RADIOACTIVE DEPOSITS Many deposits of uranium- and thorium-bearing min- erals are known in eastern and southern California, but as of December 1954, only one deposit (the Miracle mine) has made as much as a railway shipment of uranium ore; both uranium and thorium are scarce in northern California. Most of the uranium deposits are in the southern Sierra Nevada and the Mojave Desert region of southern California. Thorium deposits are con- fined to the Mojave Desert region. Although more than 20 different radioactive minerals have been reported from California, only a few of these contain sufficient uranium or thorium to be classed as potential ore minerals. Two classes of radioactive minerals — principally uranium-bearing and principally thorium-bearing — are described in the following pages. Uranium Deposits Distribution. Although deposits of uranium-bearing minerals are known from widely scattered localities throughout California, most of them occur in the southern part of the Sierra Nevada and in the Mojave Desert physiographic provinces. The deposits are closely grouped in places, particularly in the vicinity of Kern River Canyon northeast of Bakersfield and in the Mo- jave Desert near the town of Mojave. Other clusters of uranium prospects include those in eastern ll County and southeastern Lassen County and in v 1 Kern County near Taft and McKittrick. The Kern River Canyon deposits are characteri II near surface concentrations of autunite along fnl in granodiorite and in weathered granitic rock acl to the fractures. The Mojave Desert deposits are (I terized by the occurrence of secondary uraniun ni erals, which include autunite, meta-autunite, torba and carnotite, along fractures and bedding pla 3! mid-Tertiary sedimentary or volcanic rocks. Deposits of primary uranium minerals seem to j] common and more widely scattered throughout th n than the deposits of secondary uranium mineral.' v may be due, in part at least, to the difficulty of idt il ing the dark-brown to black primary minerals, s'ffl pitchblende, in a deposit, whereas the vividly ol secondary minerals stand out in sharp contrast. 1 quantities of uraninite have been identified at the a doned Rathgeb gold mine (Rickard, 1895), Calg County, and are thought to be present at the Greel claims (Truckee Canyon group), Nevada County, ;i the Thum Bum claim near Big Bear Lake, San Bfe dino County. Other primary uranium minerals, i I ing samarskite, euxenite, davidite, and brannerite I been identified in crystalline rocks and in placer d{« in east-central and southeastern California. Size and Shape. Most of the deposits containir|B ondary uranium minerals are small, rarely exceji 100 feet in their greatest dimension. The deposits P Radioactive Deposits in California ^erable variety in shape, but the majority are iy tabular. Commonly, the secondary uranium min- sire erratically distributed on joint surfaces adja- o mineralized faults; deposits of this type are iially tabular in the plane of the fault and range n few inches to 10 feet in width and commonly do iceed 100 feet in length. Nearly horizontal, roughly iilar deposits are present where the secondary ura- i) minerals coat bedding planes of sedimentary rocks •e erratically disseminated through porous portions 1 rock adjacent to these bedding planes. Deposits of ; rpe rarely exceed 50 feet in their greatest dimen- i nd commonly are not more than a few feet thick. ■ econdary uranium minerals commonly occur in .1 disconnected patches. ts difficult to make any generalizations about the nd shape of primary uranium deposits in Cali- i . Most of the primary uranium minerals occur as .ainated accessory constituents in granitic rocks; s:gle crystals, or locally, as small aggregates with s minerals in pegmatites ; and as clots of crystals in i; containing base-metal sulfides. ddlizaiion. The uranium deposits in California We subdivided into four groups on the basis of their 1 of occurrence. These are: (1) deposits in fissure i (2) deposits on minor fractures, bedding planes, locally, as disseminations in porous rock, (3) re- cnent deposits, and (4) deposits representing rela- ; oncentrations of radioactive minerals in granitic k or pegmatites. Only at the Rathgeb mine has a ary uranium mineral (uraninite) been found in D.ation with a secondary uranium mineral (uraco- »?)• Of the 81 uranium deposits described in the < ing pages, only 8 are thought to have been local- Imtirely by primary hydrothermal solutions. The v, ling 73 deposits contain either secondary uranium nals or unidentified uranium-bearing minerals asso- H. with secondary base-metal minerals; the uranium t 3 se deposits was probably introduced, or at least i ributed, by circulating ground water or late hydro- r!.al solutions. Jinium in quartz fissure veins generally has limited 1 rratic distribution. Whether present as a primary s ondary mineral, uranium is commonly mixed with senetal sulfides or their oxidation products. Nearly ( the deposits of this type have been found in gra- iirocks. Examples of uranium in quartz fissure veins lie the Rathgeb mine, the Rademacher, Rainbow, iRed Devil claims, the "Wild Bill group, the Pay- sr mine, and the Perry Jones claims. Ijj largest group includes those deposits in which odary uranium minerals coat fractures or bedding lis. The country rock of such deposits is diversified; ay the wall rock may be bleached and partly altered ldrothermal clay minerals; it may consist of Ter- r continental sedimentary rocks, in part tuffaceous, f r example the Rosamond prospect ; it may be Ter- * volcanic rocks such as found on the Chilson prop- I or it may be older crystalline rocks as on the ifrty and Baxter properties. Cmmonly, the greatest concentration of secondary aium minerals is in fault gouge or on joints or bed- a planes adjacent to faults. Deposits in bedded sedi- ;iary rocks seem to be confined largely to certain individual beds; the reasons for selective deposition of uranium in these beds are not fully understood, although porosity, permeability, and CaC0 3 content play a signifi- cant part. A third group includes deposits in which base-metal sulfide bodies, containing uranium, replace limestone along fractures in the rock. At the Yerih group of claims (Scotty Wilson property), San Bernardino County, a finely divided uranium mineral is intermixed with base- metal sulfides that occur as irregular masses and thin seams erratically distributed in limestone. Uranium has also been found with wulfenite in oxidized ore bodies composed largely of primary and secondary lead and zinc minerals at the Lippincott and Ubehebe mines in Inyo County. At both properties, the base-metal sulfiide ore bodies have, in part, replaced the limestone and have also filled fractures. Uranium-bearing minerals in crystalline rock have been concentrated and localized only in the sense that they may be more prevalent in some places in the rock than in others. At the Hoerner-Ross deposit, cyrtolite and betafite (?) are sparsely distributed in small pockets or clots in a thin zone in a pegmatite; at the Pomona Tile quarry in the Rock Corral area, samarskite and euxenite occur sparingly in small iron-stained patches in the pegmatite. Mineralogy. Uranium-bearing minerals repbrted from California can be divided into a group of primary min- erals, including uraninite (or pitchblende ?), brannerite, samarskite, betafite, and euxenite, and a group of sec- ondary minerals including autunite, torbernite, carnotite, and gummite (?). The primary minerals are considered to be original constituents of quartz veins containing sulfide minerals and of granitic rocks or pegmatites. The secondary uranium minerals are derived from the altera- tion of the primary minerals ; in most secondary deposits in California, however, primary uranium minerals have not been found with the secondary. According to Rickard (1895, p. 329), _ uraninite (uranous oxide) and uraconite (a name originally pro- posed for an ill-defined yellow uranium ochre, sup- posedly uranium sulfate) occur together at the Rathgeb mine in Calaveras County associated with gold in a quartz fissure vein. As described by Rickard, the urani- nite consists of acicular black crystals. On the Rainbow claim, Jackass district, Madera County, minute quanti- ties of an unidentified uranium mineral occur in a smoky quartz vein associated with pyrite, chalcopyrite, tetra- hedrite (?), bornite (?), and magnetite; the uranium mineral is probably uraninite. Minute particles of a primary uranium mineral, probably uraninite, are dis- seminated through galena and sphalerite on the Yerih group of claims, Holcomb Valley district, near Big Bear Lake in San Bernardino County. Primary uranium-bearing rare earth niobates, tan- talates, and titanates including such minerals as bran- nerite, samarskite, betafite, and euxenite have been found as accessory minerals in pegmatites and granitic rocks and as minor constituents of black sand concen- trates. According to Pabst (1954), brannerite occurs as an accessory mineral in plutonic rocks exposed about 7 miles south of Coleville in Mono County. Betafite (?) and cyrtolite described herein have been reported by Hewett (personal communication) from pegmatites -24827 Special Report 49 exposed on the Hoerner-Ross property, San Bernardino County, and samarskite and euxenite have been found in pegmatites exposed in the Pomona Tile quarry near Rock Corral, San Bernardino County. Murdoch and Webb (1948) have described other deposits of some of these rare uranium-bearing minerals. Shawe (personal communication) has reported ura- nium-bearing ilmenite, which is questionably related to the mineral davidite, from granitic rocks and placer con- centrates on the east slope of the Sierra Nevada in the vicinity of Bishop. The mineral occurs as black, anhedral grains and as hexagonal plates which have optical prop- erties similar to those of ilmenite. Chemical tests indi- cate that the ilmenite contains iron, titanium, man- ganese, cerium group of rare earths, vanadium, thorium, and uranium. The secondary uranium minerals, autunite, torbernite, meta-zeunerite (?), "gummite" (?), and carnotite have been identified from localities in the desert region of southeastern California, in the Kern River Canyon area (Kern County), and in the eastern parts of Plumas and Lassen Counties. At some properties only one of these minerals is present, whereas at other properties two or more are associated. Autunite, a hydrated phosphate of calcium and ura- nium, occurs characteristically as pale yellow-green or lemon yellow, square basal plates as much as a millimeter in size ; all the autunite is fluorescent in shades of yellow- green. Torbernite, a hydrated phosphate of copper and uranium, occurs as green, essentially non-fluorescent, square or rectangular basal plates which commonly are foliated. Most of the basal plates are extremely small, though a few are as much as a millimeter or larger in size. Metazeunerite ( ?) occurs at the Perry Jones claims, Plumas County and at the Truckee Canyon group as small, grass-green, tabular crystals. It is associated with torbernite, and fills minute cavities and fractures in quartz veins. Small quantities of "gummite" (?), a brittle and waxy, dark reddish-brown to black mineral, are found on slickensided fault surfaces at the Rosamond prospect, Kern County. It is associated with autunite, hydrated iron oxides, chlorite ( ? ) , and an unidentified dark green waxy mineral. Small specimens containing this assem- blage are more highly radioactive than normally would be expected from the small amount of autunite that is present. In this report the waxy minerals are called gum- mite ( 1 ) , as the physical properties are similar to those for gummite described in Dana's System of Mineralogy (Palache, Berman, and Frondel, 1952, p. 622-623). "Gummite" is a field term applied to substances that are essentially oxides of uranium, commonly with lead, thorium, and H 2 0, but whose true identity is unknown. The origin of the waxy minerals at the Rosamond prop- erty is unknown ; primary uranium minerals were not observed on the property nor have any been identified from the surrounding area. The anomalous radioactivity of the material might be due to abundant submicroscopic particles of autunite disseminated through an unidenti- fied mineral. Carnotite, the hydrous potassium uranium vanadate, occurs principally as a lemon yellow aggre- gate of crypto-crystalline material which, locally, con- sists of sparse micaceous plates as much as a millimeter in size. At a few places carnotite forms a thin coating of yellow, dust-like particles on joint surfaces. Autunite and gummite ( ?) occur with iron an ^ ganese oxides, chlorite ( ? ) , and opal at the Ros J prospect, Kern County; at the Chilson proper i tunite and torbernite occur as flakes and cryptoc i line coatings on joint surfaces ; and at the Luck 1 claim, Imperial County, carnotite and autuu ( torbernite, associated with talc, hydrothermal cla 4 erals, manganese and iron oxides, gypsum, and are disseminated in hydrothermally altered and bl jj wall rock. Autunite is the dominant uranium oi j eral at the Miracle mine, Kern County, where it I seminated in clay gouge and weathered graniti J adjacent to a major northwest-trending, vertica 1 ture. Autunite is also the principal uranium mini the Buckhorn claims (southeastern Lassen Cci where it coats minor fractures in rhyolitic tuff. Perry Jones claims in eastern Plumas County, tori J and metazeunerite ( ? ) associated with secondar 1 per minerals, occur as encrustations on f ractui J faces and as small cavity fillings in quartz ve 1 granodiorite. Autunite (or meta-autunite ?) is th J conspicuous secondary uranium mineral in the Si mining district a few miles northwest of Ros£§ Kern County, where at least nine uranium depos 1 grouped. The deposits appear to be along f racti J sedimentary or volcanic rocks of Tertiary age 1 quartz monzonite of Jurassic (?) age which, loc; I pegmatitic. At the Harvard Hills, east of Yern ] tunite coats fractures in layered tuffaceous sedim 1 rocks, black chert, marly sandstone, and linul Autunite and unidentified secondary uranium mil are associated with quartz and clay minerals in i re granite at the Rafferty property in Los Angeles C 1 Secondary uranium minerals are also reported fr< 1 Paymaster mine in the Solo district, although nil are available as to the mineralogy of this occuil and from the Taft-McKittrick area in Kern Cj where they are associated with siltstone and sh ( j late Miocene age. Other deposits, as for exampl Vanuray claim and Kramer Hills deposits, cl carnotite associated with clay, opal, and oxides ol and manganese in bedded clays and marls of Mi age. Grades. Most of the known deposits of urani i] California are low in grade. Much of the sampli contained in the descriptions of radioactive depo;n this report are the result of assays of select spec! collected by personnel of the U. S. Geological £| and of the U. S. Atomic Energy Commission ol mitted to those agencies by prospectors; these s£ 1 are not to be interpreted as representative of t] posit from which each was collected. The Miracle mine in Kern River Canyon, I County, shipped a railway carload (46 tons) of ur I ore averaging 0.62 percent U 3 8 to the Vitro Ur I Company plant in Salt Lake City, Utah, in August! this is the only mine, as of December 1954, to n] carload shipment of uranium ore from Cali i (Anonymous, 1954). Origin. The uranium deposits in California al netically related to the intrusion of granitic rock i I as to Tertiary volcanic activity. Studies have indl that most of these deposits are in either of two enfl Radioactive Deposits in California (1) pre-Tertiary pegmatites, granitic rocks, and H quartz veins in which primary uranium minerals ebeen found, and (2) Tertiary volcanic, near-sur- ■ ltrusive, pyroclastic, and tuffaceous sedimentary I in which many of the deposits of secondary am minerals occur. 'ruium-bearing minerals in pegmatites, such as aiat the Hoerner-Ross property, at the Pomona Tile rr, and elsewhere, are probably primary constit- tioi the pegmatite. Likewise, uranium-bearing ac- 0/ minerals in bodies of granitic rock are primary stuents of the rock. The uranium -bearing minerals a he base-metal sulfide minerals found at the Yerih a of claims and at the Rainbow claim, probably idfrom the same hydrothermal solutions that de- it 1 the sulfides. b primary source of the uranium in the deposits tning secondary minerals is more difficult to ascer- i-;he mineralogy as well as the nature of the host care different from place to place, although the host {sit many deposits are mid-Tertiary extrusive or in- a;! volcanic rocks, or sedimentary beds containing otastic material. The secondary uranium minerals, 's autunite, torbernite, carnotite, and gummite are jl if ever, formed directly from hot aqueous solu- ismanating from a cooling magma. The uranium in ieninerals has been derived from primary minerals I ere leached and dissolved either by ground waters ijlhydrothermal solutions. The dissolved uranium in ground waters was re-deposited wherever a change tr 1 chemical or physical environment caused a de- is in the solubility of the uranium. Secondary hy- nloxides of uranium, such as gummite, may form on surface of primary pitchblende or may be deposited m(solution at a considerable distance from their ri The phosphates, autunite, and torbernite have nlound in close proximity to primary uranium de- it elsewhere, but in California they occur in areas to; from any of the known primary occurrences of nfim. Vanadates, such as carnotite, are not com- iJ found close to primary uranium minerals al- uji several such associations have been reported from olorado Plateau area by Weeks and Thompson ■ p. 20). Primary uranium minerals have been nj in very few deposits containing secondary ura- njminerals so that the relationship of these minerals ni well known. However, many of the secondary >0ts occur in rocks derived from Tertiary volcanic hy and, locally, some of the felsic flows and near- f*e intrusives contain more uranium than other ^'exposed in the same area. It seems reasonable to eithat the uranium now in the secondary minerals ten derived by the leaching and solution of primary stuents of the volcanic rock. Some of the uranium y'e derived, however, through the leaching and solu- i f primary minerals in rocks other than the vol- i< by late hydrothermal solutions that accompanied ilcanic activity. Evidence of hydrothermal activity tls either contemporaneous with, or later than the csdc activity, is apparent at the Lucky Star, Van- ymd Jumpin claims, and elsewhere ; at all of these •Jrties, the wall rocks, which are in part either mid- Rry volcanic or tuffaceous sedimentary rock, are a'led and partly altered to hydrothermal clay min- is In addition, some of the secondary uranium minerals found in areas of altered wall rock are inter- mixed with hyalite opal. Thorium Deposits Thorium-bearing minerals have been reported from nearly all sections of California; they occur sparingly in most felsic plutonic crystalline rocks, in some meta- morphic rocks, in some pegmatites, and in veins; nu- merous placers containing thorium minerals are also known throughout the state. Minerals that are classed as thorium-bearing for purposes of this report include : monazite, thorite, xenotime, and allanite. Thorium occurs as a major or minor constituent in these minerals, com- monly in combination with uranium and the rare earths of the cerium group. Distribution. Thorium minerals occur in many places throughout the state, but the recent studies have been limited mainly to a few localities; these include the Mountain Pass and the Rock Corral areas in San Ber- nardino County, and the Live Oak Tank area and the Desert View claim in Riverside County. At Mountain Pass, in the northeastern Mojave Desert, thorite is as- sociated with bastnaesite, a rare earth fluocarbonate, in vein deposits. In the same area, monazite crystals are dis- seminated in a mass of rock composed dominantly of calcite, barite, quartz, and bastnaesite. Thorium-bearing allanite, monazite, and radioactive zircon are dissemi- nated in porphyritic quartz monzonite and in metaso- matically altered inclusions in the quartz monzonite at the Rock Corral area. At the Black Dog claim, about 3 or 4 miles south of Rock Corral, a vein composed in part of thorium-bearing monazite and allanite is enclosed in crushed gneiss. At the Original claim small amounts of monazite (?) are an accessory mineral in crystalline rocks. At the Live Oak Tank area monazite occurs in black sands and with xenotime in pegmatite. At the Desert View claim, central Riverside County, small amounts of monazite occur in biotite gneiss. In addition, there are numerous published and unpublished refer- ences to thorium minerals in pegmatites in southern California, in granitic rocks in the Sierra Nevada, in black sand lenses along Pacific Ocean beaches, and in placer gravels along rivers flowing from the Sierra Nevada and the Klamath Mountains. Mineralogy. Thorium-bearing minerals reported from California include thorite, monazite, allanite, and xeno- time. At most places these minerals occur only in small quantities and as minute grains; megascopic identifica- tion is normally impossible. Identification of the thorium minerals from nearly all the widely scattered localities is based on microscopic examination, x-ray, specto- graphic, or chemical analysis. Thorite has been identified at the Mountain Pass area, in placer concentrates collected near Bishop, in coastal beach sands south of San Francisco, and in placer con- centrates collected along the west slope of the Sierra Nevada (George, 1951, p. 131). It occurs in two main varieties. One variety, distinguished from the common variety because of its uranium content, is called uranoan thorite and has been found as green, rounded detrital grains commonly having elongate prismatic habit. As far as is known, uranoan thorite has not been found in place. The other variety of thorite, which has been found in place at Mountain Pass, the Rainbow group of claims, 8 Special Report 49 occurs characteristically as euhedral crystals and as rounded grains which are yellow-orange to brown. Monazite, the cerium group phosphate, occurs most commonly as light to dark golden brown or reddish- brown grains which have a resinous luster. In some placer deposits, the monazite is in well-shaped prismatic crystals, whereas in other placers and in beach sands it is in subhedral tablets. Most of the allanite reported from California has been found in granitic rocks and in pegmatites, although some placer deposits are known. Most of the allanite grains are small prismatic crystals; locally, however, prismatic crystals as much as a few inches in length have been reported. The allanite is amber to dark brown or black in color and may have a vitreous or resinous lus- ter or, through alteration, a dull earthy luster. Xenotime, occurring as colorless, rounded equidimen- sional grains in Pacific Ocean beach sands has been re- ported by Hutton (1952). Melhase (1936) found xeno- time in pegmatite (Riverside County) as well-formed, yellowish-brown, tetragonal crystals, a maximum of £-inch in length. SUGGESTIONS FOR PROSPECTING FOR URANIUM AND THORIUM The following generalizations may be of some assist- ance in prospecting for uranium in California: (1) The areas in California that appear to be the most favorable for the discovery of uranium are those adjacent to known deposits in the Mojave Desert province, the southern part of the Sierra Nevada in the vicinity of the Kern River Canyon (Kern County), the northeastern part of the Sierra Nevada (eastern Plumas County and southeastern Lassen County) , the San Bernardino Moun- tains (San Bernardino County), the Basin and Range province of eastern California, and southern California (Riverside and Imperial Counties) ; (2) Uranium de- posits in fractures and shear zones that appear to have been formed from groundwater or hydrothermal water will most likely contain secondary uranium minerals; (3) uranium is commonly associated with areas in which the wall rocks are bleached and altered to hydrothermal clay minerals, some deposits contain introduced silica in the form of hyalite opal as fracture coatings; (4) limonite, either as stain or massive gossan, is commonly radioactive in the vicinity of secondary uranium de- posits. Uranium has been found most commonly in California as small deposits of secondary minerals erratically dis- tributed on fractures and bedding planes in various types of rock. The secondary deposits occur most abun- dantly, however, in mid-Tertiary volcanic, pyroclastic, and tuffaceous sedimentary rocks and in Tertiary con- tinental sedimentary rocks. Some secondary deposits have been found in altered and unaltered granitic rocks and in altered base-metal sulfide bodies in limestone. The source of the secondary uranium deposits has not been demonstrated conclusively, although many of the de- posits are believed to have formed during periods of mid-Tertiary volcanic activity. Most of the deposits are distributed along fractures and bedding planes which have been channel-ways for groundwaters or for hydro- thermal solutions. Minerals containing uranium rarely occur with those containing thorium. Such an association is found in placers that are composed mainly of complex ref minerals that were originally scattered err through pegmatite or occurred as minute accessoi tals in plutonic rocks. Thorium minerals have been reported from parts of the state — Mountain Pass, Rock Corral a: where in San Bernardino County, the western Riverside County, granitic rocks of the Sierra 1 stream gravels along most of the major rivers th westward from the Sierra Nevada, and beacL along the Pacific Coast of northern California. Th distribution suggests that the thorium minerals ai ent in small amounts in most of the granitic in rocks in the state and that careful sampling of along river draining areas where such rocks are ( would probably add considerably to the list of t occurrences. ECONOMIC EVALUATION Studies of radioactive deposits in California sh< 1 although uranium- and thorium-bearing miner; i widely distributed and occur in various geologic e a ments throughout the state, economic concentrat g these minerals are rare. As of December 1954, oi i mine has made as much as a carload shipment of u: I ore from California and very few other properties tl the state might be considered as potential soma uranium ore under present conditions. A compl j praisal of the uranium-bearing properties is not p 1 however, because exploration on nearly all of th 1 been limited to surface or near surface prospectii ■ the character of California uranium deposits at d 1 not known. Thorium-bearing minerals might be economics I covered as a by-product of gold dredging operat ■ as a by-product in the recovery of rare earth ml from the bastnaesite deposits at Mountain Pass. > I the known thorium deposits in California can ll cessfully exploited solely for thorium under prese m nomic conditions. DESCRIPTION OF THE RADIOACTIVE DEPOS Although many localities containing concentrat >j radioactive material are known throughout Califll the following descriptions of individual propert I limited to those that have been examined sine* I Brief reference is made to a few deposits which, j have not been studied by the U. S. Geological Sui jj the U. S. Atomic Energy Commission. The depos I listed alphabetically by counties in the accomp m table and their location is shown on the location n '.j In the following pages the deposits are grou] I geomorphic provinces because many of them are I in the same or similar geologic environment will given province. The boundaries of the geomorphi' 1 inces are essentially the same as those described 1 aj kins (1941). A few deposits, for example thosll Searles Station (Kern County), and near Big Bead (San Bernardino County), are only short distanc oj side the boundaries of the Mojave Desert provini fl convenience, the descriptions of these deposits a m included under the Mojave Desert province headii Mojave Desert Province The Mojave Desert province, which includes p A Kern, Los Angeles, San Bernardino, Riverside ai 1 perial Counties, in the southeastern part of thetfl Eadioactive Deposits in California LIST OF PROPERTIES ' V -\i^r,;„— fl STOKES AND STOWELL PROPERTIES PERRY JONES GROUP GUIOICE MINE BROWN PROPERTY CORNELIA GROUP BUCKHORN GROUP TRUCKEE CANYON GROUP RATHGEB MINE GEN. U. S. GRANT MINE RELICH PROSPECT RAINBOW CLAIM WILD BILL GROUP UBEHEBE MINE 13 GEESLIN AND FISCUS LIPPINCOTT MINE 14 PROPERTY 4 GREEN VELVET CLAIMS IS BUSTER TOM CLAIMS 4 SANTA ROSA MINE 16 EMERALO QUEEN CLAIMS 4 EMPRESS MINE 17 BLUETT PROPERTY 5 WATTEN8ARGER PROSPECT 18 MIDDLE BUTTE MINE 5 SILVER STRAND CLAIM 19 MAMIE CLAIM 5 DANCING DEVIL NO 16 ROSAMOND PROSPECT 5 CLAIM 20 VERDI OEV CO PROPERTY 5 KERGON GROUP 21 SECTION 10 ANOMALY, MOJAVE WAYNE CASE PROPERTY 22 MINING DISTRICT 5 MIRACLE MINE 23 JUMPIN CLAIM 5 LAST CHANCE CLAIM 24 GOLOENROD CLAIM 5 SUN DOG CLAIM 25 STILLWELL PROPERTY 5 ALLEN PROPERTY 26 VANURAY CLAIM 5 EMBREE PROPERTY 27 YELLOW TIGER CLAIM 6 KERVIN PROPERTY 28 KRAMER HILLS 6 RADEMACHER CLAIM 29 FIEND CLAIM 6 CHILSON PROPERTY 30 LOOKOUT LODE CLAIM 6 ALPHA, BETA, GAMMA BAXTER PROPERTY 6 CLAIMS 31 ROLL PROPERTY 6 JOSIE BISHOP GROUP 32 RAFFERTY PROPERTY 6 SILVER LADY CLAIMS 33 COON CLAIMS 6 JEEP NO 2 CLAIM 34 HARVARD HILLS 6 MOHAWK MINE GROUP 35 HOERNER - ROSS MOUNTAIN PASS AREA 36 37 PEGMATITE 6 LUCKY BELLE GROUP 38 RED DEVIL CLAIM 7 RAINBOW GROUP 39 GRIMES CANYON AREA 7 PAYMASTER MINE 40 THUM BUM CLAIM 7 SANTA MARGARITA YERIH GROUP 7 PROSPECTS 41 ST PATRICK GROUP 7 WAKEFIELD PROPERTY 42 LUCKY SEVEN CLAIM 7 SURPRISE NO 1 CLAIM 43 ZABDIEL MINING CO. LOPERNA PROPERTY 44 CLAIMS 7 MITCHELL PROPERTY 45 ALPHA CLAIMS 7 DUALITY OIL CO, ROCK CORRAL AREA 78,7 PROPERTY \ 46 STEINER CLAIMS 8 COPPER MOUNTAIN CLAIM 8 HOMESTRETCH GROUP 8 URANUS CLAIMS 8 LIVE OAK TANK AREA 8 OESERT VIEW CLAIM 8 GRANITE MINE 8 AURORA NO. 1 MINE 8 CRESCENT MINE CLAIM 8 LAOY KATY CLAIMS 8 TENN-CAL GROUP 9 \ LUCKY STAR CLAIM 9 AMERICAN GIRL MINE 9 Figure 1. Location of radioactive deposits in California examined by geologists of the U. S. Geological Survey and the U. S. Atomic Energy Commission during the period 1948 to 1954. 10 Special Report 49 Table 2. Radioactive occurrences in California (by counties)." Map No. b Location < Section Town- ship Range Type Country rock Radioactive mineral (s) Other minerals San (in 92 89 91 90 15 17 14 16 13 26 32 50 48 22 30 20 Rathgeb mine American Girl mine Lady Katy group Lucky Star claim- Tenn-Cal group.- ._ Bonanza mine d G reen Velvet claims Joe McCulley property Lippincott mine Santa Rosa mine Ubehebe mine Wingate Pass area d Allen property Josie Bishop group Bluett property Buster Tom claims Wayne Case property Chilson Dancing Devil No. 16 claim 34 18-19 7 36? 14 10 25 13 (proj.) 26, 35 (proj.) 1, 2 (proj.) 83 miles NW. of Baker 15 30 4N. 15S. 9N. 12S. 12S. 15S. (proj.) • 19S. 18S. 15S. 17S. 14S. 25(?) 36 (?) 23 27S. 29S. ION. UN. 27S. 28S. 27S. 12E. 21E. 14E. 19E. 19E. 40E. 37E. 44E. 40E. 39E. 40E. 33E. 37E. 13W. 14W. 31E. 40E. 31E. Calaveras County Vein Imperial County Vein Fracture coat- ings, dissemi- nated Disseminated Disseminated Inyo County Replacement? Disseminated Replacement Replacement and fissure filling Replacement and fissure filling Replacement and fissure filling Fracture coat- ings Kern County Spring deposit Fracture coat- ings Fracture coat- ings Fracture coat- ings Fracture coat- ings, dissemi- nated Fracture coat- ings, dissemi- nated Accessory min- erals in peg- matite Slate, amphibo- lite Gneiss Granite, diorite Schist, quartzite felsic intru- sives Schist Sedimentary rocks of Pale- ozoic age Clay, shale & sandstone Limestone of Paleozoic age, Granite of Jurassic age Dolomite, quartz monzonite, minette of Paleozoic age Limestone, an- desite, basalt of Permian (?) age Dolomite, quartz monzonite, minette of Paleozoic age Limestone chert, rhyolite Granite Granite, alas- kite dikes of Paleozoic age Tuffaceous sand- stone & quartz monzonite Granitic rock Granodiorite Dacite of Ter- tiary age Pegmatite cut- ting granodi- orite Uraninite, ura- conite Meta-torbernite? Autunite?, car- notite, tor- bernite Torbernite and yellow U min- eral Autunite Secondary ura- nium minerals Radium (?) mineral Autunite Autunite, gum- mite (?) Secondary ura- nium minerals Torbernite, au- tunite (?) Gold, quartz Quartz, kyanite, mica Quartz, Fe oxides Clay, talc Kyanite, Fe and Mn oxides, gypsum Cu, Ag, Pb min- erals, idocrase, garnet Clay minerals, quartz (sand) Cu, Pb, Ag sulfi- des, taetite minerals Galena, sphal- erite, second- ary Pb and Zn minerals, Fe oxides, wulfe- nite Galena, sphal- erite, second- ary Pb, Zn, and Cu min- erals Galena, sphal- erite, second- ary Pb and Zn minerals, Fe oxides, wulfe- nite Quartz, Pb and Cu carbonates Calcite (lime- stone) Pyrite, iron oxides, quartz Limonite Limonite quartz, clay Limonite, clay 0.022 7( UiC 0.02-1 0.10-1 3 eUj 0.016 lOXbjn 0.05 I 0.051 1.30 e 'i 0.04 Oi .003 Biotite 0.47 el i 0.121i 0.25 V Radioactive Deposits in California 11 Table 2. Radioactive occurrences in California (by counties)" — Continued. Location « Section Town- ship Range Type Country rock Radioactive mineral (s) Other minerals Sample data (in percent) Embree property. Emerald Queen. Geeslin and Fiscus_ Goldenrod claim. ._ Jumpin claim Kergon group Kervin property- .. Last Chance claim . Loperna property. - Mamie claim Middle Butte rnine. Miracle mine Quality Oil Co. property . Rademacher claim 8 Rosamond prospect- Section 10 Anomaly, Mojave Mining District Silver Lady claims Silver Strand claim . StilJwell property . 5 Sun Dog claim. 3 9 Surprise No. 1 claim. Vanuray claim _. Verdi Development Co. property. 24 34 (?) 34(?) 4 9, 10 20 23 22 2 18 16 20 22 2 25 10 10 10 35 26 36 27S. 32S. 32S. 9N. 9N. 27S. 27S. 27S. 30S. ION. ION. 27S. 32S. 28S. ION. 9N. 30S. 25S. ION. 28S. 30S. UN. ION. 33E. 35E. 23E. 13W. 13W. 32E. 35E. 32E. 21E. 12W. 13W. 32E. 23E. 40E. 13E. 13W. 36E. 32E. 13W. 32E. 21E. 8W. 13W. Disseminated Fracture coat- ings, dissemi- nated Fracture coat- ings Fracture coat- ings Fracture coat- ings Fracture coating, disseminated Fracture coating Disseminated Fracture coating Fracture coating Fracture coating Fracture coating disseminations Fracture coatings Vein Fracture coatings, disseminated Fracture coatings, disseminated Fracture coatings, disseminated Fracture coatings Fracture coatings, disseminated Accessory mineral (s) in pegmatite Fracture coatings Fracture coatings, disseminated Fracture coatings Quartzite, gneiss Tuffaceous sand- stone Siltstone & shale Dacite of Ter- tiary age Rhyolite of Ter- tiary age Granodiorite Granitic rock Tactite, marble, granite Siltstone and and shale Rhyolite Rhyolite, porphyry and tuff Granodiorite Siltstone and shale Granite of Jurassic age Tuffs, breccia sediments of Tertiary age Latite and granodiorite Granite of Jurassic (?) age and volcanics of Pliocene (?) age Marble Lithic tuffs of Tertiary age Pegmatite Siltstone and shale Sandy clav of Micene age Tuffaceous sandstone, granitic rock Primary ura- nium mineral and guminite (?) Secondary ura- nium (?) min- erals Secondary ura- nium minerals Garnet, limonite. fluorite Ca carbonate Autunite "gum- mite"? Autunite Torbernite, autunite Secondary uranium minerals Autunite, radon gas(?) Autunite Autunite, gummite? Autunite Meta torbernite Radium or radon gas decay products(?) Autunite Secondary uranium minerals Carnotite Meta-autunite Iron oxides Iron oxides Clay minerals fluorite, molybdenum mineral Iron oxides 7.5eUaOs 0.054 UaOi 0.32 UsOb 0.041 U 0.002 TJ— 0.037 U 1.08 UsOs 0.11 UsOs 0.055 UsOs 0.04 U 3 0« Clay minerals Clay minerals Iron oxides Gold, base- metal sulfides, quartz Mn and Fe oxides Molybdenum minerals, Fe and Mn oxides garnet, quartz 0.025U 0.62 U3O9 (shipment) 0.06 UsOs 3X background 0.002 U-0.59U Approx. 0.2 U 0.071 UaOs 31.10 U»Os (select) Pyrite, arsenopyrite Fe oxides Mn and Fe oxides, opal 0.012 U-0.14U O.HeUsOs 0.105U 3 O 8 0.11 UsOs 0.056 U 0.18UjOs 12 Special Report 49 Table 2. Radioactive occurrences in California (by counties)" — Continued. Map No. b Location ■ Section Town- ship Range Type Country rock Radioactive ineral (s) Other minerals Sampl (in pc 10 12 Wattensbarger prospect 63 Lookout Lode claim Rafferty property Rainbow claim Relich prospect Wild Bill group Truckee Canyon group. Brown property Guidice mine Perry Jones claims Stokes property. Stowell property 87 Aurora No. 1 mine Crescent mine claim 85 Desert View claim Granite mine Live Oak Tank area 83 Uranus claims 23 26 18 13 36(?) 25 13 18 24 24 26 36(?) 31, 32 1 25S. 8N. 7N. 4S. 5N. 3S. 31E. Lo 8W. 8W. 24E. 27E. 31E. 18N. 23N.(?) 24N. 24N. 24N. 25N. 25N. 6S. 6S. 5S. 6S. 2S. 2S. 17E. 16E.(?) 16E. 16E. 17E 8E. 8E. 14E. 14E. 10E. 15E. 9E. 10E. Accessory mineral in pegmatite s Angeles County Vein Disseminated Madera County Vein Mono County Disseminated? Vein Nevada County Vein Plumas County Pegmatite access, mineral Vein Vein Disseminated Disseminated Riverside County Vein Fracture coating(?) Disseminated Fracture Disseminated Disseminated Pegmatite and aplite Quartz monzonite, aplite dikes Granite, aplite dikes Granodiorite of Jurassic (?) age Rhyolitic tuff Quartz monzonite Granodiorite and grani tized sediments Pegmatite Granitic rock Granodiorite Hot springs deposits in metasedimen- tary rocks of Mississippian age Granite Granite and gneissic granite Biotite gneiss Granite Granite, gneiss, gabbro-diorite metasedi- ments Granite gneiss, gabbro-diorite, quartz-biotite ?ch : st Autunite Chalcopyrite, secondary Cu minerals, quartz Hydrothermal clay, quartz Quartz, chalcopyrite, tetrahedrite, bornite, pyrite Primary(?) uranium mineral (s) , metazeunerite Gold, tenorite, cerussite, chalcopyrite, iron oxides, clay, quartz Pyrite, chalcopyrite, malachite 0.02 1 0.2 UiO' 0.003 U 5X back ij 0.37 U«( Torbernite, metazeunerite (?) Radium mineral (8) Chrysocolla, malachite, molybdenite, scheelite Chrysocolla, malachite, iron oxides Fe and Mn oxides 0.50 UK 35X bad 5X back id 0.094 U 111 0.66 eU, 0.001 Monazite (?) Monazite and Xenotime Allanite (?) and monazite (?) Quartz, Cu minerals Fe and Mn oxides Cu, Fe, and Mn minerals Titanite, zircon, biotite 10X bad M 0.094 el) 0.15eU, 0.005 10X bad nJ 0.035 eU 0.005 U, 0.015' i Radioactive Deposits in California 13 Table 2. Radioactive occurrences in California (by counties)"- — Continued. Location • Country rock Radioactive mineral (s) Other minerals Sample data (in percent) Section Town- ship Range Type San Bernardino C ounty 9. 10, 11, 14, 15 2N. 4E. Disseminated Biotite-granite, metamorphic rocks 0.12U Alpha, Beta, Gamma claims. . - ? 18 28S. 8N. 41E. 7W. Fracture coat- ings (?) Fracture coat- ings Felsic intrusive Altered granite Pyrite, second- ary Cu min- erals, Fe oxides, gyp- sum Clay, caliche 3X background 3X background 23(?) UN. 2W. Disseminated Calcareous and phosphatic (?) sandstone and limestone, Barstow fm. (Miocene) Ca phosphate (bone mate- rial) 0.016 eU, 0.013 U (cal- careous sand- stone) 0.30 eU, 0.28 U (Fossil bone) 19 IN. 8W. Fracture coat- ing, dissemi- nated Diorite, gneiss, fine-grained granite Urano-thorite(?), thorite(7), al- lanite Quartz, hema- tite, magnetite chlorite, mag- netite musco- vite 0.28eU 3 Os, 0.13 UsO« 0.30 ThO j (Select) 15 9N. 6W. Fracture coat- ings Sandy limestone Carnotite Fe oxides 0.035 UjO s Harvard Hills - ? ION. 3E. Fracture coat- ings Miocene tuf- faceous sand- stone, marly sandstone, limestone, chert Autunite, carno- tite (?) 0.085 U 15 9N. 6E. Pegmatite Quartz monzo- nite Cyrtolite, beta- fite Orthoclase, bio- tite, magne- tite, quartz 19,30 IN. 8E. Disseminated Granodiorite (locally gneis- soid) Monazite (?), al- lanite (?) Biotite 0.005 UaOj, 0.33 ThOj 10 17N. 12E. Fracture coat- ing Quartzite, phyl- lite Carnotite Fe, Mn, Cu, oxides, jasper, chert, cobalt bloom 0.41 eU 13, 14 9N. 6W. Fracture coat- ings Miocene tuff, marl beds, limestone Carnotite Clay 0.003 U 17, 18, 19, 20 15N. 10E. Veins Granitic rock Chalcopyrite, pyrite, Fe oxide 0.019 UaOs 18 2N. 4E. Disseminated, fracture coat- ings Granite Allanite (?) monazite (?) Biotite 0.08 eU 7. 8, 17 16N. 13E. Vein Quartz monzo- nite Quartz 5X background Mountain Pas? area including Birth- day claim, Easter Sunday group, and other properties 16N. 15MN. 13E. 14E. Vein, dissemi- nated Pre-Cambrian gneiss, shon- kinite, barite- carbonate rock, andesite Thorite, mona- zite Calcite, barite, ankerite, li- monite, quartz, bastnaesite, parasite 5.50 ThO a 0.32 U Original and Pack Saddle claims d — ? 6N. 13E. Disseminated Granitic rocks, metasedi- mentary rocks Monazite (?) 0.005 U, 0.06 Th 8 13N. 10E. Vein Pre-Cambrian limestone Secondary ura- nium minerals Clay, quartz 0.04 UaOa j 13N. 10E. Pegmatite Granitic rocks Monazite, thor- ite, hyalite opal Quartz, feldspar, magnetite, 1 hematite 0.027 U 14 Special, Report 49 Table 2. Radioactive occurrences in California (by counties)" — Continued. Location ° 1 Map Type Country Radioactive Other Samj. an No> Town- ship rock mineral (s) minerals (in p ggj Section Range 70 Red Devil claim. ? 6N. 18E. Vein Granite of Jur- Quartz, stibnite, cinnabar, 0.0841 i assic (?) ace stibiconite 78, 79 Rock Corral area including Jenkins, 3N. 4E. Disseminated, Quartz monzo- Allanite, zircon, 0.15 el Conkey, Black Dob claims, and 2N. 5E. placer nite, biotite- samarskite, and Pomona tile quarry rieb inclusions of Jurassic (?) age monazite, euxenite 65 Roll property - - 18 8N. 7W. Disseminated Biotite granite Allanite Biotite 0.72 el J 0.02( < 45X ba> J 74 St. Patrick group _ 7, 8 IS. IE. Disseminated Schist Pitchblende (?) Monazite (?) Feldspar, quartz Biotite 80 Steiner claims 31 2N. 7E. Disseminated Biotite schist 0.055 e allanite (?) 72 Thum Bum claim. 28 2N. 2E. Disseminated Granite of Jur- Primary (?) uranium min- Magnetite feld- (12 U assic (?) age spar, quartz. pre-Cambrian eral (s) biotite schist, diabase dike 60 Yellow Tiger claim . . 25 ION. 6W. Fracture coat- Tuff of Miocene Secondary ura- 025 I ings age nium minerals 73 Yerih group (Scotty Wilson property) 3, 4 2N. IE. Replacement Limestone of Paleozoic age Pitchblende? Pyrite, pyrrho- tite, chalcopy- rite, galena, sphalerite 0.37 el! 76 Zabdiel Mining Co. property ... 8, 16 2N. 4E. Disseminated Pre-Cambrian schist and gneiss, pegma- tite, aplite Biotite 0.116 U J Unnamed d 14 UN. 7W. Fracture coat- Sandy clay of Carnotite ings Miocene age Tuolumne County 9 Gen. U. S. Grant mine . . . ? 3N. 15E. Radon gas Slate, schist of Gold, quartz, 5X back i of Paleozoic age iron oxides Ventura County 71 Grimes Canyon area 7, 18 3N. 19W. Disseminated ? Sedimentary rocks, inter- stratified and intrusive (?) volcanic rocks of Tertiary age 3X back n a List does not include the 85, or more, thorium- or uranium-bearing placer deposits examined by personnel of the Union Mines Development Corporation, U. S. Bureau of Mini Atomic Energy Commission, and U. S. Geological Survey or placer occurrences listed in Murdock and Webb (1948). b Numbers correspond with those used on map (fig. 1). All township and range locations are based either on the Mount Diablo meridian or the San Bernardino meridian. d Not shown on map (fig. 1). e Proj. — projected. consists of an extensive interior region of mountain matites of pre-Tertiary age, and Tertiary continent* I ranges separated by broad, alluvial-filled desert valleys. volcanic rocks. The Mojave Desert is separated from the Sierra Nevada Concentrations of radioactive materials in the M % province and the Basin and Range province on the Desert are associated with foliated, pre-Cambriai .1 north by the Garlock fault, and from the Transverse rocks, such as those at Mountain Pass and in the j Ranges province on the southeast by the San Andreas Oak Tank area. They are found in pegmatites and fault. The eastern boundary of the Mojave Desert prov- tonic granitic rocks, such as those, for example, at jj ince lies outside of California ; only the part within Cali- Corral, the Pomona Tile quarry, Lookout Lode (1 f ornia is covered by this report. and elsewhere. In addition, they are associated witl fl The dominant bedrock types in the region consist of tiary rocks at many localities. The Tertiary rocks, m crystalline, metamorphic rocks of Paleozoic age and older sisting largely of continental lake beds and volu Paleozoic sedimentary rocks, some early Mesozoic sedi- flows, breccias, and tuffs, are the host for most ctJl mentar y rocks, intrusive plutonic rocks s md rel ated pe g- occur rences of sec< mdary urani um minerals. Radioactive Deposits in California 15 Bsamond Prospect (53).* Small quantities of tuite and gummite (?) occur in tuffaceous sedimen- ■u-ocks at the Rosamond prospect in the SW| sec. . 10 N., R. 13 W., San Bernardino base and merid- l.Phe property is about 10 miles south of Mojave, i County. In 1950, when the property was examined • ie Atomic Energy Commission by F. M. Chace of i . S. Geological Survey, it was owned by the South- i 'aeific Railroad ; and in 1952, when examined by W. Walker and Luther H. Baumgardner, it was idf lease to Mr. Clifford Gillespie of Hollywood, Cali- Workings made in 1952 consisted of a short adit, .'(coot shaft and shallow pits. Nine holes were drilled vly 2 feet wide and 15 feet long. Bie- to coarse-grained tuffaceous rocks, which were ,ped by Simpson (1934) as part of his Rosamond nation of Miocene age, are exposed in the area, cing in the tuffs strikes N. 40° W. and dips approx- a>ly 15° to the SW. Small faults, which strike N. 'E. and are nearly vertical, cut and offset the ling. Autunite is erratically distributed as joint and mire coatings and as disseminations in the tuffaceous in and adjacent to some of the faults. An assay lect chips collected from a mineralized fault indi- ( a uranium content of 0.14 percent, whereas assays i 2-foot continuous channel sample across the fault 1 ate a uranium content of 0.09 percent. }ddle Butte Mine (51). The Middle Butte mine is id by Mrs. Mary B. Johnson of Whittier, California, i about 8 miles southwest of Mojave, California in -.6, T. 10 N., R. 13 W., Kern County. The workings ist of approximately 5,000 feet of shafts, drifts and )isuts from which over $150,000 in gold was mined, cock exposed in the workings consists of altered v ite porphyry and tuff, part of which is kaolinized. ifgold-bearing veins strike N. 26° W. and dip 35° Eradiation intensity of 0.15 MR/hr was noted in the .lings on the adit level where autunite sparsely coats id rhyo-dacite and dacite, associated with Red utain andesite, is in the Summit Range 6 miles north Rodsburg, Kern County, in sec. 36 ( ?), T. 28 S., R. E Mt. Diablo meridian. Torbernite and autunite are d as small green and yellow foliated crystals on ^surfaces and in small cavities in the dacite. The trim-bearing minerals have been concentrated by ad water circulating along the contact between rhyo- di and dacite. The deposit had been prospected by ) pen cuts, and a shaft about 25 feet deep, when inned by C. W. Chesterman and F. H. Main in 1946. j hilson property, known also, at various times as 'onsen property, Summit Diggin's, Uranous claim, Ernes' property, was under lease to Mr. Philip J. ris of Los Angeles in December 1951. I hip sample from the face of one open cut in the uuized zone assayed 0.121 percent equivalent ura- m Geiger counter readings on outcrops of the unmin- lfed dacite indicate no more than about 0.002 per- t quivalent uranium. able 5. Sampling data, Kramer Hills, San Bernardino County, California. n -r ... Description and locality 12-foot channel sample of clay, dolomite, including zone sampled by No. 261; from trench in Barstow formation 3-foot channel sample of clay, dolomite, marl, yellow-stained; from trench in Barstow formation Grab sample, greenish-yellow-stained, thick- bedded, dolomitic marl, from portal trench in Barstow formation Grab sample, marly clay, stained greenish- yellow; from shaft about 700 feet north- west of trench Grab sample, shale from trench in Barstow formation; smear of yellow secondaiy uranium minerals on bedding planes Grab sample, from 5-inch dolomite bed in trench in Barstow formation Grab sample, 12-inch shale zone in trench in Barstow formation Grab sample, 12-inch shale zone in trench in Barstow formation Grab sample, 12-inch shale zone in trench in Barstow formation eU (percent) 0.002 0.004 U (percent) 0.002 0.003 0.000 0.001 0.001 0.001 0.064 0.11 0.006 0.006 0.012 0.016 0.008 0.008 0.004 0.003 nr: DPH-1 to DFH-5, incl., collected by D. F. Hewett from SW1 sec. 15, T. 9 N.t. 6 W. Collection site is a trench 50 ft. long and 10 ft. deep. Vanuray Claim (59). The Vanuray claim is in sec. 26, T. 11 N., R. 8 W., about 2| miles northwest of Boron, Kern County. In November 1951, it was owned by Mr. C. J. Roy croft of Boron. Prior to the discovery of ura- nium on the property, an 18-foot pit about 100 feet in diameter was excavated, presumably to exploit clay de- posits on the property. The uranium is in sandy clay which probably is a part of either the Ricardo formation or the Rosamond forma- tion (Gale, 1946) of late Tertiary age. Bedding in the clay strikes N. 30° E. and dips approximately 40° NW. A few, indistinct, minor shear zones in the clay are as much as 1.5 feet in width. They strike about N. 70° W. and dip steeply. Carnotite occurs with opal and minor amounts of iron and manganese oxides as fracture coat- ings in the shear zones and as sparse disseminations in the sandy clay in and adjacent to the shear zones. A selected grab sample, taken where the radioactivity is highest, assayed 0.056 percent uranium. A composite of chip samples taken from a 12-foot zone that included 1.5 feet of a weakly mineralized shear zone assayed 0.018. A grab sample of wall rock assayed 0.005 percent ura- nium. Kramer Hills (61). In 1947, D. F. Hewett, U. S. Geological Survey, discovered yellow stains in prospects in the Kramer Hills in sees. 12 and 14, T. 9 N., R. 6 W., San Bernardino meridian, which he tentatively identi- fied as carnotite. Following positive identification of the yellow stain as carnotite, the prospects were examined in January 1949 by D. G. Wyant of the Geological Survey and D. F. Hewett. Claims covering the property are owned by O. H. Ball, Los Angeles. At the time of the examination in 1949, workings on the claims consisted of a trench approximately 100 feet long, two shallow shafts, and several prospect pits. The Kramer Hills area consists of a pre-Cambrian basement complex overlain by marine Paleozoic sedi- mentary rocks that are intricately folded, faulted, and intruded by granitic rocks of Jurassic (?) age. The basement and Paleozoic rocks are overlain by a thick sequence of non-marine Cenozoic sedimentary and inter- bedded volcanic rocks. The uranium deposits occur in the Barstow formation of Miocene age which consists, in this area, of a sequence of pale green volcanic ash beds and interbedded white or buff clay and marly clay beds that are, in part, dolomitic. A basalt flow rests uncon- formably on the ash and clay beds. Locally, on joints and bedding surfaces exposed in the prospect pits, the marly clay beds are stained red, greenish-yellow, and canary yellow; some of the yellow stain is composed of minute particles of carnotite and some of the greenish-yellow stain has been identified as hydro-muscovite. Readings taken at 13 localities with a Geiger counter indicate anomalous radioactivity only slightly above background readings. Yellow Tiger Claim (60). The Yellow Tiger claim is on the north flank of the Kramer Hills in sec. 25, T. 10 N., R. 6 "W., Kern County. It is owned by G. V. Ander- son and M. I. Shelton, and is leased to W. L. Durham and L. Wachter, all of Colton, California. Workings on the property in February 1954 consisted of three bull- dozer trenches, each about 50 feet long. Yellow second- ary uranium minerals stain fracture surfaces in volcanic tuff of the Barstow formation of Miocene age. Radio- 20 Special Report 49 activity measured by the U. S. Atomic Energy Com- mission is slightly over three times background ; a select sample from the site of highest measurement assayed 0.025 percent U 3 8 . Fiend Claim (62). The Fiend claim is on the south end of the Kramer Hills in sec. 15, T. 9 N., R. 6 W., Kern County. It is owned by D. B. McGee and A. R. Klein- kauf, Houston, Texas. Carnotite occurs with iron oxide in thin-bedded sandy limestones of the Barstow forma- tion of Miocene age. The workings consist of several prospect pits. Maximum radioactivity on the claim is 10 times background count. Chip samples taken over 2-foot intervals by the U. S. Atomic Energy Commission as- sayed as high as 0.035 percent U 3 8 . Lookout Lode Claim (63). The Lookout Lode claim is in the northeast corner of sec. 9, T. 8 N., R. 8 W., San Bernardino meridian, about 25 miles northeast of Lan- caster, Los Angeles County. In March 1952, it was owned by S. J. Curtis and Earl Hollingsworth of Lancaster. At that time, development consisted of 2 small pits about 100 yards south of an abandoned gold mine. The pits expose about 6 feet (strike-length) of a mineralized shear zone in quartz monzonite, aplite, and pegmatite of Cretaceous (?) age. The shear zone is a maximum of 1.5 feet in width. It strikes N. 40° E. and is nearly vertical. Abundant quartz, lesser amounts of chalcopyrite, pyrite, tenorite, azurite, hydrated iron ox- ides, manganese stain, and minute quantities of an un- identified black uranium mineral are in the shear zone. Samples of mineralized rock taken from the shear zone by Mr. S. J. Curtis and analyzed by the U. S. Atomic Energy Commission contained slightly less than 0.02 percent equivalent uranium. Testing of the dump for radioactivity at the abandoned gold mine indicates gamma ray activity the same as, or only slightly above, the background count. Baxter Property (64). The Baxter property is in the Silver Mountain district a few miles southwest of the Kramer Hills. The deposit, which in 1950 was owned by Mr. N. Baxter of Hemet, California, is in sec. 18, T. 8 N., R. 7 W., San Bernardino meridian. He explored the de- posit by a bulldozer trench 50 yards long. The country rock is altered granite which is cut by a network of veins containing clay and caliche. Radioactivity of some of the vein material is about 3 times background count, al- though no uranium minerals are visible. Roll Property (65). The Roll property consists of 24 placer claims in sec. 18, T. 8 N., R. 7 W., San Bernardino County. It is owned by Michael J. Roll of Anaheim, Cali- fornia, and Ray Heatherington of Buena Park, Cali- fornia. The claims cover level valley fill about 10 feet thick. Rounded hills of biotite granite are nearby. Workings on each of three claims consist of bulldozer trenches and a shaft 10 ft. deep. The shafts expose the biotite granite beneath the valley fill. Abnormally high radioactivity appears to be confined to approximately 3 feet of gra- nitic detritus that is under about 2 feet of soil. Eighteen inches of the radioactive zone that was sampled by the U. S. Atomic Energy Commission was found to contain 0.03 percent U 3 08. One sample submitted to the U. S. Geological Survey by Mr. Roll contained 0.72 percent equivalent uranium and 0.026 percent uranium; :g the radioactivity of the sample was caused by tl n bearing allanite. Rafferty Property (66). The Rafferty proper! is the Willsona mining district in sec. 26, T. 7 N., B San Bernardino meridian, about 25 miles east cj| caster, Los Angeles County. In 1950, the depoiii owned by John and Mike Rafferty of Adelantc 3j fornia. The property has been developed sporadic yJ hand labor since its discovery in 1948. Exposures at the deposit consist of deeply wes el granite in which aplite dikes and quartz veinlets i companied by zones of hydrothermal alteration. A J and other secondary uranium minerals occur wi'SJ minerals as late fracture coatings in hydrotherma m Chip samples taken from the zones contained as n :1h 0.2 percent U 3 8 . Coon Claims (67). The Coon claims are in : ( ?), T. 11 N, R. 2 W., about 9 miles north-north $ Barstow, San Bernardino County. The owner ii ij Coon of Burbank, California. Anomalous radioactivity, amounting to a maxh w 0.5 MR/hr is present in calcareous and tuffaceoiri ments of the Barstow formation of Miocene ag 1 beds strike northwest and dip 70° N.E. Many t| active fossil bone fragments occur in clay and shi S are strongly reactive to phosphate tests. Even t j careous sandstone beds show positive reaction fo m phate. No uranium minerals were identified; it I gested that uranium in the samples collected fr I Coon claims occurs as traces in the phosphate i m present in the bone material and possibly in a ph( la cement in the sandstone. Table 6. Sampling data, Coon claims, San Bernard* County, California. Sample number JCG-1 .. JCG-2 ._ JCG-3 .. Description and locality Calcium carbonate rock near dry wash. Calcareous sandstone near dry wash Phosphatic fossil bone material near dry wash vicinity of discovery monu- ment eU (percent) 0.024 0.016 0.30 U (percent) Ml 0.018 )l 0.013 ■ 0.28 I Harvard Hills (68). Secondary uranium mi have been found in several places in the vicinity ! Harvard Hills in T. 10 N., R. 3 E., San Berri meridian, about 9 miles east of Yermo. Anomalous ! activity has been detected both north and south o Highway 91 which, in this area, parallels the r Pacific Railroad. Lode mining claims, includi; North Star Nos. 1 to 5, the Moonbeam, Martha II Jolly Boy, cover most of the mineralized areas. Lj many of the claims were owned by the Harvard', and Development Company of Los Angeles; some?* claims, however, were apparently owned by other t areas of highest uranium concentration have bfti plored by means of several pits as much as 12 feels The Harvard Hills, which are in the center of ? roi alluvial valley, are composed of thin-layered lafc be consisting of tuffaceous sandstone, marly sandstoni liJ Radioactive Deposits in California 21 m, clay, and chert of the Barstow formation. Autun- id carnotite (?) occur principally as coatings on Hire and bedding surfaces, particularly in parts of a action containing chert and limestone. The uranium jfeave been introduced by the lake waters, or it may k been a primary constituent of the tuff aceous debris t ■ sandstone and redistributed by circulating ground- tk Aseries of radioactivity traverses across the Harvard 1 indicate that the uranium minerals are concen- iti principally on the north and northwest slopes of elnlls. Anomalous radioactivity, however, was de- tl only where shallow pits expose mineralized zones, trample assayed by the U. S. Geological Survey con- iriti 0.025 percent uranium; another sample, assayed ■ |e U. S. Atomic Energy Commission, contained 0.085 rmt uranium. Berner-Ross Pegmatite (69). The Hoerner-Ross k atite, in central San Bernardino County, is on the siside of the crest of a nearly conical peak south of eaain ridge of the Cady Mountains; the Cady Moun- r are an isolated mountain unit approximately 5 I wide in a northerly direction and 9 miles long in , isterly direction. The peak is 7 miles N. 56° E. of wot station on the Santa Fe Railroad. Hector station 3 miles east of Barstow. The pegmatite is accessible j desert road 3 miles east from Hector, north under r lroad bridge, then 6 miles northeast up a wash to e;ast side of the peak. It also may be reached by atlling another desert road north from Hector for Ife 2 miles, then east 4 miles to a wash, and then up 3 rash to its end, which is another 4 miles from the suvest road. From the end of the wash, a steep trail, m 700 feet vertically over a horizontal distance of io : 2,500 feet, leads up the bare ridge to the deposit, oiecord of studies or mapping exists for that part of eJady Mountains containing the Hoerner-Ross peg- afte. In 1945, however, the eastern and southern parts i e Cady Mountains were mapped by Cordell Durrell 13), in connection with a study of the celestite de- lls along the southern slope. IirrelPs geologic map shows that the southeastern n of the Cady Mountains is Tertiary volcanic rock ; lit flows occur at the base of the section and are .'elain successively by andesite flows, rhyolite tuffs, k playa desposits containing beds of celestite. His a also shows a small area of granite in the saddle prating the Cady Mountain mass from the hills lying ae southeast. This granite was later classified as i;tz monzonite and will be considered as such in this ajr. The quartz monzonite appears to form the higher n of the Cady Mountains in which the pegmatite oc- uj It is pale reddish-brown, where fresh, and is •csely crystalline. Crystals of feldspar in the quartz ozonite range in size from | to f of an inch in di- Iper; grains of quartz and biotite are smaller. Thin :cons show that the rock is composed of orthoclase and iodine, 35 percent; quartz, 30 percent; plagioclase i:lesine), 25 percent; microperthite, 5 percent; and icte, 3 percent. The monzonite shows several systems f )ints, but lacks the layering or foliation common in tore-Cambrian rocks of this region, hmerous dikes of a rock similar in composition to the u-tz monzonite, though of a finer grain size, occur in the vicinity of the Hoerner-Ross pegmatite. A thin sec- tion of the dike rock shows quartz 35 percent ; orthoclase and microcline, 30 percent; plagioclase (andesine) and microperthite, 25 percent; magnetite, 5 percent; biotite, 3 percent ; and sphene, 2 percent. The dikes trend north- west roughly parallel to the pegmatite. The pegmatite body strikes about N. 10° W. and dips 65° W. It is about 100 feet long and 25 feet wide at the widest part, and is roughly elliptical in shape. The contact between the pegmatite and the enclosing quartz monzonite is sharp. The owners report two other small bodies of sim- ilar pegmatite nearby. The pegmatite, as exposed in an open cut 40 feet long and 10 feet deep, is roughly separable into two layers. The lower (eastern) layer is about 12 feet thick, faintly layered, and is made up largely of feldspar, with minor amounts of magnetite, quartz, green mica and other minerals. The predominant mineral, flesh-colored coarse- ly crystalline feldspar, in places has cleavage faces sev- eral inches in diameter. Locally, it has been replaced by feathery white albite. Magnetite occurs in the flesh- colored feldspar as small isolated masses as much as 2 inches long. Quartz, in the lower layer, occurs as small pipe-like bodies several inches in diameter and 6 to 15 inches long. The longer axis of these bodies is normal to the foot-wall of the pegmatite. Within the lower layer are several rounded pale yellow to green masses of an incoherent material. One of these is several inches in diameter and 10 inches long. The rounded masses are composed largely of coarse fragments of feldspar and lesser amounts of green mica, small quartz crystals, and minute tetragonal crystals of strueverite. This mineral assemblage is slightly radioactive. Rosettes of biotite plates, as much as 20 inches in diameter, were found in the lower layer. Thin plates of biotite, 5 to 8 inches long, radiate outward from centers. The rosettes contain sparse crystals of highly radioactive cyrtolite, some of which are clearly tetragonal, while others appear hexag- onal in cross section. The upper layer of the pegmatite also is about 12 feet thick. It contains large masses of white quartz which have apparently replaced parts of the original feldspar. A lens, about 36 inches long and about 20 inches thick, composed of biotite, feldspar, magnetite, and cyrtolite is exposed in the residual feldspar of the upper layer. The lens contains plates of biotite ^ to £ of an inch thick and as much as 6 inches in diameter, which sepa- rate flat plates of feldspar and magnetite. Small crystals of cyrtolite are found in the biotite and along the con- tact of the biotite and the feldspar. Small octahedrons and grains of a uranium mineral, tentatively identified as betafite, occur in the feldspar plates and in the mag- netite. Laboratory tests show that the betafite (?) con- tains uranium, titanium, and niobium (columbium). The outer shells of the octahedrons and grains are pale yellowish-green and fine-grained ; the interiors are dark green and glassy. Approximately 5 to 10 grams of the uranium mineral can be extracted from about 25 pounds of the feldspar-magnetite-biotite rock that makes up the lens. Unless many other lenses are present in the downward extension of the pegmatite, the amount of uraniferous material present is negligible. 22 Special Report 49 Paymaster Mine (40). The Paymaster mine, in the Solo district, is 10 miles S. 80° E. of Baker, in sec. 8, T. 13 N., R. 10 E., San Bernardino meridian. In 1950, the mine was owned by Mr. Joseph Ostringer of Baker. Development work consists of two shafts and an adit. The country rock is pre-Cambrian limestone that is brec- ciated by many fractures and faults; many of the frac- tures and faults are filled with vein quartz and gouge. Near the surface, yellow secondary uranium minerals occur in the brecciated limestone as fracture coatings and as impregnations in the gouge along veins. At depth, radioactive zones in the limestone are associated with the quartz veins. Assays of grab and channel samples of the radioactive material range from about 0.003 to 0.04 percent uranium. Rainbow Group (39). The Rainbow claims are in the Solo district, about 12 miles S. 69° E. of Baker, San Bernardino County. They were owned by Glenn and Blanche Alexander in 1952. At that time, exploration workings consisted of a 15-foot shaft on the Rainbow No. 2 claim. The country rock consists of foliated granitic mate- rial, presumably of pre-Cambrian age, that has been in- truded by a pegmatite dike. The dike strikes N. 55° W., is vertical, and is exposed along the strike for nearly 50 feet ; throughout this distance it ranges in width from 6 inches to 3 feet. Dominant minerals in the pegmatite are feldspar and quartz. Erratically distributed in the pegmatite are irregular, dark gray to black, metallic masses of hematite that are as much as 10 inches in greatest dimension. The hematite is slightly magnetic and contains small amounts of magnetite. Disseminated in the hematite are anhedral crystals of slightly altered and iron-stained monazite, euhedral and anhedral crys- tals of thorite, and minor amounts of unidentified min- erals. Joint surfaces in the hematite and, locally, in the pegmatite are coated with hyalite opal that fluoresces a brilliant green under ultraviolet light. The opal may be uranium-bearing as suggested by the fluorescent green color; it is believed that another unidentified uranium mineral is also present. A select sample, collected by the U. S. Geological Sur- vey, that contained hematite, quartz, and minor amounts of monazite, thorite, and hyalite opal, assayed 0.027 per- cent equivalent uranium and 0.027 percent uranium. A sample submitted by the owners to the U. S. Geological Survey laboratories assayed 0.02 percent uranium. Lucky Belle Group (38). The Lucky Belle group of 11 claims is on the southern foothills of the Shadow Mountains in parts of sees. 17, 18, 19, and 20, T. 15 N., R. 10 E., San Bernardino County. The claims are owned by Percy Priest and Vergel Fergen of Santa Monica, California, and Grant Hann of Venice, California. Slightly radioactive quartz-bearing veins occur in frac- tures in granitic bedrock that underlies the claims. Radi- ation intensity is three times background count along the parts of the veins where chalcopyrite, pyrite, and iron oxide were observed. Samples collected by the U. S. Atomic Energy Commission indicate a U 3 8 content of at least 0.019 percent. Jeep No. 2 Claim (34). The Jeep No. 2 claim is about 6 miles northwest of Clark Mountain Peak in sec. 10, T. 17 N., R. 12 E., San Bernardino County. It is owned by Albert Schmidt and W. R. Johns of Valley 1 California, and leased to Manning Briggs and assoc Development of the property includes several hm feet of workings; the mine was worked for copp 1907. Bedrock exposed in the area consists of dolomitic stone enclosed by quartzite, phyllite, and schist oi Cambrian age. Carnotite occurs with oxidized co lead, zinc, and manganese minerals in small replace bodies and along veins in the limestone. The majoi structure in the mine strikes N. 46° E., dips steep the northwest and is exposed for 280 feet. The richest sample collected from the property b U. S. Atomic Energy Commission contained 0.41 pe equivalent uranium. Mohawk Mine Group (35). Abnormal radioacl amounts to five times background count at the Mo mine group of claims in the southern foothills of ( Mountain in parts of sees. 7, 8, and 17, T. 16 N., R. 1 San Bernardino County. The property is owned by hawk Mines, Inc. of Fillmore, Utah. The highest r activity on this group of claims occurs in a q 1 stringer cutting quartz monzonite. The quartz str: is near a limestone-quartz monzonite contact where zinc, and copper minerals have been found. No ura minerals have been identified. Mountain Pass Area (36, 37). Radioactive mat* in association with major concentrations of rare-i minerals occur in the Mountain Pass area in the n east part of San Bernardino County about 58 i southwest of Las Vegas, Nevada, via U. S. Highwa; The area is of particular interest because of the pres 1 of abundant non-radioactive bastnaesite (cerium-lai fc num fluocarbonate) and parisite (cerium-lanthai ^ calcium fluocarbonate). These rare-earth minerals is] deposit were discovered in 1948 by the detection of r; I active thorium-bearing minerals that occur with 1| (Pray and Sharp, 1951). Since 1949, extensive stii have been made of the rare-earth deposits and the I ciated thorium minerals (Olson and others, 1954) 1 only a brief reference to the thorium deposits wil presented here. The rare-earth and thorium deposits of the Mouri Pass area are confined to a northwest-trending bloel pre-Cambrian rocks, nearly 7 miles long and more J 2 miles wide, that is bounded on the north and wesl faults and on the east and south by the alluvhu A Ivanpah Valley. Dominant rock types within the tl are hornblende and mica gneisses, biotite granite gnl augen gneiss, and minor amounts of dike rocks of rl to intermediate composition. Intruded into the I Cambrian rocks are masses of biotite shonkinite, syel and granite; they, in turn, are cut by andesite dl Also present in the pre-Cambrian block are masses I veins of carbonate rock composed of many mine I principally calcite, dolomite, barite, quartz, bastnaeaj and parisite. The carbonate rocks cut the potash- 1 intrusives as well as the pre-Cambrian rocks. Abnormally high radioactivity, largely due to thorffl in thorite and monazite, has been found in many pli in the Mountain Pass area. Most of the anomaM activity occurs in or adjacent to areas underlain [ 1 carbonate rock, although locally the shonkinite is | normally radioactive. The distribution of the rare-eij Radioactive Deposits in California 23 neals, bastnaesite and parisite, which locally amount ir)re than 50 percent of the carbonate rock, appar- bj has little or no effect on the distribution of pilous radioactivity, whereas the distribution of lo te and other oxides of iron is commonly closely ■p to areas of high gamma-ray activity. Most of the liictive monazite has been found as crystals scattered tlj largest mass of carbonate rock. Thorite, and hy- i 'rite or thorogummite, on the other hand, are the 1 ant radioactive minerals in areas containing oxides iiln. i e than 120 samples have been collected from the uain Pass area by the U. S. Geological Survey for iljds of uranium and thorium content. Samples have Trollected from many of the claims lying between ! irthday Claims on the northwest and areas south t£ Windy group of claims on the southeast. Analyses lif the original shaft, and crosscut southward on 1 o-foot and 50-foot levels for distances of 20 feet 1 feet, respectively. In the spring of 1952, all of orkings were inaccessible. triple of radioactive material was submitted by Mr. Mindte to t Division of Mines laboratory. The radioactivity was found t'be associated with yellow, orange, and gray crystal inter - gwths in magnetite. The crystals were identified as altered z:on carrying thorium and some uranium. The most altered cstals (gray color) were found to be the most radioactive. T; magnetite itself is not radioactive. "of this information obtained from Wright, L. A., and others. ( 5 'i 1 . The mine workings are mainly in a crushed and broken zone in massive Furnace limestone of Vaughan (1922) of Mississippian(?) age. Elsewhere on the prop- erty are exposures of quartzite, black, fine-grained, foliated metasedimentary rocks, calc-hornfels, and intru- sive granitic rocks. Hydrothermal sulfides including pyrite, pyrrhotite, chalcopyrite, sphalerite, galena, and argentite occur locally as irregular masses and thin seams in the limestone. A uranium mineral, probably uraninite, is erratically distributed in masses of the sulfide minerals. Radioactivity traverses in the vicinity of the shaft col- lar, and tests of the mine dumps, indicate only slightly greater than background count of gamma-ray activity. Select specimens, however, have a count as high as 50 times background as measured with a portable Geiger Counter. Samples submitted by Mr. Barnes to the U. S. Atomic Energy Commission contained as much as 0.37 percent equivalent uranium and 0.32 percent uranium, but the quanity of this material is small. St. Patrick Group (74). The St. Patrick group of claims is in sees. 7 and 8, T. 1 S., R. 1 E., San Ber- nardino County. They are owned by Patrick D. Haugh and Ralph D. Claxton of San Bernardino, California, and Earl H. Gilliam, Jr., of Birmingham, Alabama. Anomalous radioactivity as high as 45 times back- ground count was measured along a fault in schist. Feld- spar and quartz are present in the radioactive zone. No uranium minerals have been identified, although pitch- blende may be present in small quantity. Workings on the property at the time of examination consisted of a 15-foot adit. Rock Corral Area (78, 79). In 1949, prospectors dis- covered several small masses of rock containing thorium- bearing minerals in an area about 2 miles wide and 5 miles long in the vicinity of Rock Corral, about 53 miles east-northeast of San Bernardino. In 1952, an examina- tion of the area by D. F. Hewett, G. W. Walker, R. M. Moxham, and L. H. Baumgardner of the U. S. Geological Survey indicated that some exposures of pegmatite, vein material, masses of biotite-rich rock in plutonic crystal- line rocks, and locally, the plutonic rocks themselves, contain concentrations of radioactive minerals. Several properties, including the Jenkins, Conkey, and Black Dog claims, and the Pomona Tile quarry, cover some of the areas of highest radioactivity. At the time of the examination, excavations consisted of several pits, or shallow shafts, in the most radioactive parts of the area. Dominant rock types exposed in the Rock Corral area are pre-Cambrian biotite gneiss, siliceous metasedimen- tary rock, dark interlayers of metavolcanic ( ? ) rock, and intrusive quartz-monzonite of Mesozoic age. The metamorphic rocks are metasomatically altered, locally, and the intrusive rocks are contaminated with partly assimilated blocks of wall rock. Thorium-bearing allanite, as well as radioactive zircon and monazite, are conspicu- ous accessory minerals in biotite-rich inclusions (or small roof pendants) in the plutonic rocks and, locally, also in the plutonic rocks; some alluvial deposits derived from these rock types are also proportionately high in allanite, zircon, and monazite. Petrograpbic analysis of selected rock specimens collected in the area indicates that parts of the biotite-rich inclusions contain more than 7.0 per- cent of allanite and more than 1.0 percent of zircon. In 24 Special Report 49 addition, specimens of the plutonie rocks contain as much as 4.5 percent of allanite and 1.5 percent of zircon. Quartz-feldspar pegmatite at the Pomona Tile quarry contains minute amounts of samarskite, euxenite, allan- ite, and monazite associated with biotite, either magnetite or ilmenite, and other unidentified minerals. Remnants of an allanite- and monazite-bearing vein, about 15 feet long and as much as 5 or 6 inches wide, are exposed in biotite gneiss on the Black Dog claim. A selected specimen from the Black Dog claim, sub- mitted by Mr. B. Bauer to the U. S. Geological Survey laboratories, contained 1.87 percent equivalent uranium, 0.25 percent uranium, and 0.61 percent thoria. Selected specimens of the biotite-rich material assayed as much as 0.15 percent thorium; however, the quantity of ma- terial of this grade is small. Several analyses of the plu- tonie rock indicate that in some areas the rock averages about 0.008 percent equivalent uranium ; many millions of tons of material of this grade are present in the Rock Corral area. Lucky Seven Claim (75). The Lucky Seven claim, owned by P. T. Kinney of Fullerton, California, is in sec. 18, T. 2 N., R. 4 E., San Bernardino County. The only workings on the claim consist of discovery pits. Anomalous radioactivity, as high as 1.0 MR/hr, is attributed to the presence of thorium-bearing allanite and monazite disseminated in biotite pods in granite. Radioactivity slightly exceeding background count was noted along joints in the granite. The richest sample from this property assayed by the U. S. Atomic Energy Commission contained 0.08 percent equivalent uranium. Zabdiel Mining Company Claims (76). The Zabdiel Mining Company property, comprising 24 claims, is in the foothills at the east end of the Little San Bernardino Mountains in sees. 8 and 16, T. 2 N., R. 4 E., San Ber- nardino County. Workings on the property consist of several prospect pits. The area is underlain by pre-Cambrian schist and gneiss cut by pegmatite and aplite dikes. No uranium minerals were seen, although radiation intensity as high as 25 times background count was noted over an area 50 feet wide and 300 feet long. A specimen of biotite schist, collected by the U. S. Atomic Energy Commis- sion indicated a U3O8 content of 0.116 percent. Alpha Claims (77). The Alpha claims, comprising 14 claims, are approximately one mile north of Saddle Rock Springs in Bear Valley in sees. 9, 10, 11, 14, and 15, T. 2 N., R. 4 E., San Bernardino County. The owners are Anthony D'Alessandro and associates of Azusa, Cali- fornia. Workings on the property consist of trenches, pits and shallow shafts. The bedrock is similar to that of the Rock Corral area and consists essentially of biotite- rich rock in plutonie crystalline granitic rocks. Anoma- lous radioactivity is apparently related to biotite concen- trations in the plutonie and metamorphic rocks. A sample of metamorphic rock submitted to the U. S. Geological Survey laboratory by Mr. D'Alessandro con- tained 0.12 percent uranium. Red Devil Claim (70). Radioactivity slightly above background count has been found on the Red Devil claim, Danby district, in the NWi T. 6 N., R. 18 E. (projected), about 12 miles southeast of Essex in San Bernardino County. When examined in 1952, the ^ was owned by L. M. Donnel of Fenner, Californh was under lease to R. A. Mesick of Cathedral City, fornia. Exploration workings consisted of two si pits in a mineralized shear zone. Bedrock in the vicinity of the pits consists of g of Jurassic (?) age, although elsewhere on the metamorphic rocks of possible pre-Cambrian age a posed. A shear zone which strikes N. 30° W. anc 80° SW, and is seen only in the granitic rocks, co 1 discontinuous patches of vein material composed inantly of silica, lesser amounts of stibnite, cini stibiconite ( ? ) , iron oxides, and small amounts • unidentified uranium mineral. Locally, along the zone, the wall rock is hydrothermally altered and ble{ Only small quantities of radioactive material found when the property was tested for gamma-n tivity; all of the anomalous radioactivity is confir the mineralized shear zone. A select specimen, whicl tained abundant stibnite, cinnabar, and stibiconitt assayed 0.076 percent equivalent uranium and percent uranium. Steiner Claims (80). The Steiner claims are typical desert terrain of low barren hills in sec. 2 N., R. 7 E., San Bernardino County. The pro] owned by Carl Steiner of Bellflower, California, m reached by following the Giant Rock road from J Tree, California, for 6.2 miles and then turning on a dozer trail for half a mile to the low, rolling Development of the property consists only of lo( work. Abnormal radioactivity, a maximum of 1.0 M is present along a small fault in dark- colored b itt schist, and is attributed to thorium-bearing mini probably monazite and allanite, associated with th io- tite. A select sample collected by the U. S. Atomil ergy Commission indicated an equivalent uranium * tent of 0.055 percent. Copper Mountain Claim (81). The Copper 1 ■ tain claim is approximately 8 miles northwest of Tw f nine Palms, California, in sec. 19, T. 1 N., R. 8 E. a Bernardino County. The owner is Carl Kramer of 1 * tynine Palms, California. Development of the projl when visited by the U. S. Atomic Energy Comm fl in January 1954, consisted of several shallow disc tj pits. Bedrock in the vicinity of the claim consists of d i and gneiss (?) intruded by fine-grain granite. El activity, as high as 1.0 MR/hr, was detected ale I shear zone in these rocks ; the shear zone was trace' W feet. Although no uranium or thorium minerals I identified at the time of examination, uranothorite, 1 ite, and allanite, associated with quartz, hematite, rth, the province is terminated where the Cenozoic lciiic rocks of the Cascade Range and the Modoc atnu overlie the rocks characteristic of the Sierra Ua. Ti oldest rocks in the province consist of a sequence Pleozoie sedimentary rocks, most of which have been i;aically metamorphosed to phyllite, quartzite, re- pstUized limestone, amphibolite and amphibolite iii quartz-mica schist, and graphite schist. Strati- illically above the Paleozoic rocks is a thick sequence jjsozoic slate or phyllite and various types of meta- llic rocks. The Paleozoic and Mesozoic rocks, ex- sej predominantly in the west and northwest parts of ; rovince, have been invaded by great masses of plu- lijrock composed largely of granodiorite and quartz- •npnite but including other plutonic rock types and '.&y, small masses of pegmatite. Quartz veins, many yich contain base-metal sulfides and gold, were in- deed into the Paleozoic and Mesozoic rocks during b janing stages of plutonic invasion. Ahough radioactive minerals are widely distributed roghout the province, significant concentrations are rdHutton (1951a), Pabst (1954), Shawe (unpub- bithe General U. S. Grant mine (Tuolumne County). S'eral uraninite crystals, as large as a quarter of an ■in diameter, have been submitted by prospectors to J J. S. Atomic Energy Commission field office in krsfield, California. These crystals were reported to vegmatite in granite. No uranium minerals were ttied. Mr. Brinkley submitted a select specimen of uitite to the U. S. Atomic Energy Commission for ywhich contained 0.25 percent U 3 08. - Dog Claim (25). The Sun Dog claim is about nes west of Havilah, California, in sec. 9, T. 28 S., EE., Kern County, and is owned by Harold Hart of gBeach, California. Workings consist of 50 feet of .ground workings and three surface cuts; all but srface cut were made previously by gold prospec- „ Jedroek in the vincinity consists of granite. Ano- 03 radioactivity as high as 1.7 MR/hr was measured tl U. S. Atomic Energy Commission in a pegmatite » laving a northeast strike and a low angle dip to sutheast. The pegmatite is 10 to 20 feet thick and xbsed along its length for as much as 600 feet, •jlite and arsenopyrite (?), but no uranium min- Iswere seen on the property. A select sample of the icctive material assayed by the U. S. Atomic Energy D'ission contained as much as 0.14 percent equiva- ;j 3 8 and 0.105 percent U 3 8 . Wtenbarger Prospect (18). The Wattenbarger p/ty is about 5 miles west of Greenhorn Summit V in sec. 23, T. 25 S., R. 31 E., Kern County, and wed by Doyle Wattenbarger and James Stewart of l*e, California. It is in heavily wooded mountainous •ai at an altitude of about 5,000 feet. Workings on joperty consist of bulldozer cuts. Anomalous radio- vjy, a maximum of 0.25 MR/hr, was measured by Tj S. Atomic Energy Commission in pegmatite-aplite e^in granitic rocks of the Sierra Nevada batholith. Rer Strand Claim (19). Anomalous radioactivity iffient in white, impure Paleozoic ( ? ) marble on the n Strand claim in sec. 10, T. 25 S., R. 32 E., Kern ny. The claim is leased by John C. Compton of alo, California. Development work on the property sits of two adits, one 150 feet long, and the other 100 t Jmg. Bedrock in the vicinity is marble, although fle occurs east of the workings. The adits, entirely olrble, were driven toward a tactite body reported to t n scheelite. iilioactivity, amounting to a maximum value of 0.2 l/jr was measured by the U. S. Atomic Energy Com- rin along fractures and silt-covered floors of solution ips in the marble. Abnormal radioactivity in the re is probably caused by the presence of radium or lc gas decay products deposited along fractures and eVities in the marble by ground water. Specimens feted at points of highest radioactivity on the prop- ywere found to be only weakly radioactive when a'irements were again made several days after the et^ns were removed from the locality. Len Property (26). Abnormally high radioactivity P'sent at a calcareous spring deposit on the Allen >]rty situated along Erskine Creek in sec. 15, T. 27 1 33 E., Kern County. The property consists of four pented claims, and is owned by John Allen of Bod- ijalifornia. The calcareous material fills fractures in aiered granite and forms a hard limy cap at the he. The calcareous rock occurs for several hundred I along the base of the hillside north of the discovery m cold spring now issues from the cut. Maximum radioactivity, measured by the U. S. Atomic Energy Commission, occurs in black sooty material underlying the limy cap rock. A select sample of the sooty material assayed 1.30 percent equivalent U 3 8 and 0.04 percent U 3 0,s; a select sample of the limy cap rock contained 0.88 percent equivalent U 3 8 and 0.01 percent U 3 8 . The anomalous radioactivity is prob- ably caused by radium. Embree Property (27). The Embree property is on the southwest slope of Laura Peak near Erskine Creek in sec. 24, T. 27 S., R. 33 E., Kern County. The property was located by Prank Lieber during September 1954 and sold to Gil Embree of Kernville, California, about a month later. Workings on the property consist of a dis- covery cut, an upper adit with 165 feet of workings, and a lower adit with 205 feet of workings. Approximately 5 miles of access roads and several bulldozer cuts and trenches constitute the remainder of the work. Mr. Embree drove the upper crosscut adit northwestward through gneiss and paragneiss, and crossed a contact be- tween paragneiss and quartzite 95 feet from the portal. The contact is gradational through several feet of para- gneiss and altered quartzite. About 45 feet of drifting to the northeast along the contact was completed before he abandoned the upper adit because of caving ground. A lower adit was driven through 150 feet of gneiss and paragneiss, and 55 feet of drifting northeastward along the contact was completed by December 1954. The finding of highly radioactive specimens of quartz- ite float containing 7.5 percent equivalent U 3 8 led to the discovery of the deposit. Samples of quartzite from the discovery cut assayed by the TJ. S. Atomic Energy Commission contained as much as 3.0 percent U 3 8 . Radiation intensities as high as 1.5 MR/hr at the surface cut and 3.0 MR/hr in the lower workings appear to be associated with dark gray to black streaks in quartzite closely adjacent to, and roughly parallel to, the gneiss- quartzite contact. Pitchblende (?) and gummite (?) have been tentatively identified as the important uranium minerals in the deposit. Sparse stains of yellow secondary uranium minerals are, in places, associated with the dark gray streaks in the quartzite. Fluor ite is indicated in a sample from the workings assayed by the U. S. Atomic Energy Commission that contained 0.08 percent U 3 8 and 1.1 percent CaP 2 . Garnet is present in the gneiss and probably accounts for some of the reddish- brown iron oxide stains observed in both the gneiss and quartzite. No shipments of uranium ore had been made from the property by December 1954. Kervin Property (28). The Kervin property is about 9| miles (direct line) southeast of Weldon, California, in sec. 23, T. 27 S., R. 35 E., Kern County, and is owned by Henry Kervin of Bakersfield, California. A prospect pit 10 feet deep is the only working. Anomalous radioactivity, a maximum of 3.0 MR/hr, appears to be associated with a northeast-trending shear zone that dips steeply northwest. The hanging wall (west side) of the shear zone is granitic rock; the foot wall (east side) is metasediments. A minor shear zone branches northward from the main shear zone. It was sampled by the U. S. Atomic Energy Commission where torbernite and a minor amount of autunite was seen. A select sample contained 0.11 percent U 3 8 . 32 Special, Report 49 Vein of rodioactive material associated with fluorite EXPLANATION Blocky quortzite^ Quortzite ' i' 1 Altered porogneiss ond quortzite (?) Gneiss Porogneiss Vertical fault [Dashed where approximately located) Fault, showing dip (Dashed where approximately located ) .10 .10=10 MR/hr (Radiation intensity) Portol and open cut PLAN OF LOWER ADIT Mopped by W A. Bowes, U.S. Atomic Energy Commission, December 1954 Trend of bonds in quortzite 85 Lineations in 'j porogneiss ? iy )_Poragneiss Plons of odits ore not in relative positions. -Coarse-grained gneiss PLAN OF UPPER A Gummite (?) streaks in quortzite 60; ''■■^Gneiss Ouortzite PLAN OF UPPER CUT 80 FEET _l Ouortzite Approximate contact. ( surface ) ^W- '^ < \- ■' ' ' \ \ Gneiss , * \ .Uppei 1 cut Pqraqneiss * v Upper dit INDEX MAP Figtjee 6. Embree property, Erskine Creek area, Kern County, California. Silver Lady Claims (33). The Silver Lady claims, owned by Mr. and Mrs. Arthur J. DeLacy of Los An- geles, California, consists of three unpatented claims in Jaw Bone Canyon in the southern extremity of the Sierra Nevada, about 20| miles north of Mojave, Cali- fornia, in sec. 10, T. 30 S., R. 36 E., Kern County. Anomalous radioactivity is associated with a shear zone in granite of Jurassic (?) age and volcanic rocks of Pliocene (?) age. The shear zone was mapped as the Silver Lady fault by H. E. Nelson and R. L. Hillier of the Atomic Energy Commission. It is as much as 70 feet wide and over 2,000 feet long, strikes N. 70° W., and is nearly vertical. Radioactivity values as high as 30 times background count were detected along the north side of the Silver Lady fault and along small shears that branch northward from the main fault; these are in highly altered granite and fault breccia. Molybdenite is disseminated through parts of north-trending branch of the main shear zone near an 18-foot prospect shaft and also was observed on the dump. Meta-torbernite has been tentatively identified in a recent open cut near the shaft. Other minerals present in the fault zone include ferrimolybdite, pyrite, iron and manganese oxides, gar- net, and quartz. A channel sample 4.5 feet wide J fault breccia assayed by the U. S. Atomic Energy I mission contained 0.071 percent U3O8. Highly 1 specimens of breccia assayed as high as 31.10 p'i U 3 8 . Coast Ranges Province The Coast Ranges province, as described by Jndary uranium minerals were discovered late in t t several places in the southeastern extremity of uthern Coast Ranges. Most of these discoveries i the eastern foothills of the Temblor Range in the ay of Taft and McKittrick, California. Autunite, nite (?), uranophane (?) and possibly other i ary uranium minerals form thin coatings along ■tres and bedding planes in shale and siltstone of iocene age in the Taft-McKittrick area. Many of deposits appear to be in northwest-trending faults, tnlarly where brecciation and iron-staining of the Dj are conspicuous. The Taft -McKittrick uranium s]cts are in an oil producing region and may be tilled by some of the same structures that serve as ilic rock. Samples collected at points of highest ms measure about 0.03 MR/hr (background: 0.02 1 ) when removed from the locality for testing. I Bill (Banner or Dog) Group (12). The Wild npup of claims is in sec. 18, T. 3 S., R. 31 E., about ilj; south of Benton, Mono County. It was owned, 9^ by the Natural Resources Development Company id Gatos, California. Development work consists of dits ; the total length of the adits is approximately eet. h.claims are underlain by a quartz monzonite intru- lat contains numerous inclusions. Within the monzonite, several mineralized quartz veins 6 to 2 feet thick strike northwest and dip at low e to the southwest. Faults, which strike approx- te r N. 25° W. and dip steeply, displace the mineral- ins; displacement on the faults is commonly less feet, h-.quartz veins contain pyrite, chalcopyrite, galena, >rjs, sphalerite, gold (native ?), and alteration :hjts of some of these minerals. A 3-inch band of ihjl rock, which is exposed for 5 feet directly be- thji quartz vein, is appreciably radioactive. Abnor- rdioactivity is also found in areas where limonite ■ russite are concentrated. No uranium minerals e ?en identified, but, because of the association with .wed iron oxides, it is assumed that the uranium is By contained in supergene minerals, h samples collected by the U. S. Geological Survey taied as much as 0.1 percent uranium. Samples e 0.11 eU, 0. Feather River Hot Springs T. 25 N., R. 8 E._ Riverside County Cottonwood Mountains district (Desert F. L. Stowell W. J. Murphy A. I. Obermiller - J J. Rakocy M. J. Roll 0.29 eU 0.13 eU, 0.36 eU 0.037 eU, ( 0.72 eU, San Benito County R. S. Hall. 0.016 eU, ( San Bernardino County G. Alexander _ 0.02 U 1.87 eU, Lucky Star claim, Silver Mountain Miss M. A. Boughey. Oscar Meyer J. M. B. Parry J. W. Vandergrif t . . . J. W. Hubble J. C. Powell J. C. Stevenson, Jr. _ 0. L. Armstrong H. J. Barrett S. C. Bedell 0.61 TW rare ear 0.019 U f0.019eU,( •J0.032eU, ( 1,0.044 eU, ( 0.12 eU, 25 mi. E. of Barstow (Harvard Hills) San Diego County Sec. 21, T. 17 S., R. 8 E 0.30 eU 0.019 U Tuolumne County Gen. U. S. Grant (Sunnyside) mine-. Ventura County 0.032 U Unknown 0.032 U 0.05 U <0.120eU A. H. Bishop . W. J. Burback G. T. Clark 0.054 U 0.011 U 0.01 U K. C. Daulton K. C. Daulton Guy Dolfi 0.005 U 0.006 U 0.015 U W. T. Duggs C. R. Ericson 50.0 U 0.014 eU, ( Radioactive Deposits in California Table 10. Radioactive samples from California submitted to the V. S. Geological Sun .1 . ey laboratories for assay — 37 Continued. Locality Submitted by Sample number Type Uranium minerals Grade (percent) .w— Continued Fresno Geophysical Co. L. W. Gaskins Joe Geiger. RW6724 AW5496, RMW510 RW7224 RW6672 W2578 AW5573, RMW587 RW6845 RW6985 W4253, AEC4702 RW2332 RW4748 RW6873 W1947 RW7324 138705 RW7105 RW7347 W2910 W1986 W2666 W2657 RW7439 RW4635 RW7182 RW6747 RW6164 Sedimentary rock w/calcite Chert, goethite, hematite, \v/ quartz, malachite, azurite Igneous rock with Cu minerals Igneous rock Granite gneiss Magnetite sand Igneous rock Altered crushed rock w/goe- thite and calcite Sandstone, granite, calcite, quartz Quartz, heulandite Clay Breccia Sedimentary rock Sand and silt Calcareous rock w/azurite and malachite Metamorphic rocks Weathered granite Rhyolite Brecciated limestone Lime-silicate rock Sedimentary rock Weathered granite Sedimentary rocks w/mala- chite and azurite Magnetite Quartz, galena, pyrite Limestone Metamorphic rock Weathered igneous rock w/ limonite Weathered sandstone Gneiss Igneous rock Coal, arkose Igneous rock w/calcite Limonite Quartz, chalcopyrite, limonite Pegmatite Igneous rocks w/secondary Cu minerals (Thorium-bearing) Meta-autunite Secondary uranium minerals Secondary uranium minerals Meta-torbernite Meta-tyuyamunite 0.38 U 0.023 U 0.037 U 0.018U 0.008 eU 0.028 U 0.027 U 0.057 U 0.45 eU, 0.034 U 0.007 eU 0.083 U 0.025 U 0.063 eU 0.83 U 0.003 eU 0.06 U 0.013 eU, 0.007 U 0.02 U 0.015 eU 0.05 U 0.008 eU 0.015 U 025 U J. E. Gibson J. J. Goot 0. J. Hansen V. R. Harrington H. K. Hennigh A. M. Jensen.- R. L. Johnson R. M. Jones A. C. Keenan N. G. Keibor M. S. Knight C. Larzealear - J. F. Mack J. F. Mack CO. Miller... J. E. Moreland.- D. F. Neuschwander E. Perry R. J. Pixler.. 048 U T. Pratt.. 17 U H. L. Rogers ... G. P. Steffen /0.046U \0.013 U 26 U J. Stevenson, Jr C. M. Stradal C. S. Tessier- E. Tucker - W8016 RW7050 RW6991 RW2076 RW5156 W1968 RW6837 RW7211 W2905-1 138798 W4347, AEC4978 0.025 U 0.02 U 0.46 U . 008 eU . 026 U H. M. Valencia- —0.01 eU . 03 eU, . 003 U E, Wagnon W. H. Wolcott T. Wood 0.007 eU, 0.08 U 0.03 eU 0.017 eU, 0.014 U M. E. Wright 0.012 U rterses in the underground t one detected radioaetivit workings in the y as much as '. replace- .0 times has also been repo cent City in Del rted in Pacific beach s Norte County (Murd ands near Cres- och and Webb, Lg')und. No uranium minerals have been identified •ii property. Other Reported Occurrences of Uranium and Thorium Minerals xrrences of thorium and uranium minerals have i ported from a number of other localities in Call- is a few of which already have been studied briefly ■ U. S. Geological Survey or the U. S. Atomic ry Commission. Of these, the uranium- or thorium- h: minerals are present in such small amounts that | ould be considered a potential source of either iim or thorium under present conditions. oizite has been reported in placer concentrates in r ravels at Placerville and the Indian Diggings in Dado County, at Trinidad in Humboldt County, i lichigan Bluff in Placer County, in the Browns- ' istrict in Yuba County, and at unspecified local- Butte, Nevada, and Plumas Counties (Murdoch ^ebb, 1948). Monazite has been reported in placer :etrates from the Ogilby district, Cargo Muchacho iriins, from the San Joaquin River near Friant, f )m the Tuolumne River near La Grange. Monazite 1948), and in the backshore zone of beaches in San Mateo County (Hutton, 1951b). Monazite occurs in peg- matites at the following places in Riverside County: Mesa Grande, 2 miles north of Winchester, near the Vonsen limestone quarry, and the Southern Pacific quarry near Nuevo (Chesterman, 1950). Weak gamma- ray activity, probably caused by thorium in monazite, has been found on the Original and Pack Saddle claims about 4 miles east-northeast of Amboy in San Bernar- dino County. The monazite (?) is an accessory constit- uent of granitic rocks. Other localities, in which minute amounts of torbernite, cyrtolite, samarskite (?), and xenotime have been reported, also are listed by Murdoch and Webb (1948). Thorite has been found in placer gravels along the Feather, Yuba, American, Mokelumne, Tuolumne, and Merced Rivers (George, 1951). Allanite, which may or may not be radioactive, has been reported from the Ford mine, Calaveras County, from the Eagle Mountain iron deposits, Riverside County, from the Gassenberger Ranch, Tulare County, and elsewhere (Murdoch and Webb, 1948). 38 Special Report 49 In 1952, G. W. Moore and J. G. Stephens of the U. S. Geological Survey conducted a reconnaissance in Cali- fornia in search of new deposits of uranium-bearing car- bonaceous rock. During the investigation, 50 localities were examined, including 46 that contain coal or car- bonaceous shale and 4 that contain petroliferous mate- rial. A total of 63 samples of carbonaceous rocks were taken for analysis from 38 of the localities. The uranium content of the samples ranges from less than 0.001 per- cent to a maximum of 0.020 percent. The most significant concentrations of uranium in carbonaceous rocks in Cali- fornia are : Newhall prospect, Los Angeles County, 0.020 percent uranium ; Fireflex mine, San Benito County, 0.005 percent uranium; American lignite mine, Amador County, 0.004 percent uranium ; and Tesla prospect, Ala- meda County, 0.003 percent uranium. Positive fluorescent bead tests for uranium in base metal-quartz veins in rhyolites in the Wingate Pass area in Inyo County have been reported ; the area is about 83 miles northwest of Baker, near Death Valley. Geiger counter readings in the area, however, averaged only 7 counts per minute above background. The uranium con- tent is too low to be of further interest. Weak radioactivity occurs erratically in mineralized shear zones on the Alpha, Beta, and Gamma (31) claims in San Bernardino County about 10 miles northwest of Johannesburg. The shear zones contain minor amounts of pyrite, secondary copper minerals, hydrated iron oxides, gypsum, and an unidentified radioactive mineral. Reconnaissance of the Grimes Canyon area (71), Ven- tura County, indicates the presence of minor amounts of an unidentified radioactive material associated with vol- canic rocks of mid-Tertiary age. The volcanic rocks are interstratified with sedimentary rocks of mid-Tertiary age that they may locally intrude. Throughout most of the area, Geiger counter readings are the same as, or only slightly above, background count ; however, locally, readings as much as three times background have been recorded. On October 6, 1949 the Mariposa Gazette published an article on the discovery of uranium in the Mother Lode district by Dr. F. E. Tiffany of Mid Pine, Cali- fornia. Dr. Tiffany was contacted by geologists of the U. S. Atomic Energy Commission ; he stated that the deposit was in Yosemite National Park about 28 miles from Mid Pine, but was inaccessible at the time. He further stated that the deposit consisted of calciocar- notite (tyuyamunite), specimens of which contained as much as 4.0 percent U3O8. This material was reported to occur in a clay seam 4 to 8 inches wide and approxi- mately 400 feet long, between granite and slate. LITERATURE CITED Anonymous 3954, First California uranium ore shipped: Cali- fornia Div. Mines, Mineral Inf. Service, v. 7, no. 10, p. 18. Boyle, E. M., 1918, Mines and mineral resources of Plumas County : California Min. Bur. Rept. 16, pp. 60-61. Chestermnn, C. W., 1950, Uranium and thorium : California Div. Mines Bull. 156, pp. 361-363. Durrell, Cordell, 1953, Geological investigations of strontium de- posits in southern California : California Div. Mines Special Rept. 32, pi. 8. Frondel, J. W., and Fleischer, Michael, 1952, A glossary utJ nium- and thorium-bearing minerals : U. S. Geol. Survi ]j» 194, 2d, 23 p. Gale, H. S., 1946, Geology of the Kramer Borate distric [en County, California : California Jour. Mines and Geology fl no. 4, pp. 325-378, 3 pis., 4 figs. George, D. R., 1951, Thorite from California, a new occ ag and variety : Am. Mineralogist, v. 36, no. 1, pp. 129-132. Hutton, C. O., 1951a, Allanite from Yosemite National Par' "jj umne County, California : Am. Mineralogist, v. 36, m . 233-248. Hutton, C. O., 1951b, Uranium thorite and thorian monazi w black sand pay streaks, San Mateo County, California ( t) Geol. Soc. America Bull., v. 62, no. 12, pt. 2, pp. 1518-1 . Jenkins, O. P., 1941, Geomorphic provinces of California 'a] fornia Div. Mines Bull. 118, pp. 83-88, 3 figs. incl. relief I dex maps. MacKevett, E. M., 1953, Geology of the Santa Rosa lea< m Inyo County, California : California Div. Mines Specia epi 34, 9 pp., incl. 3 figs., 2 pis. McAllister, J. F., 1955, Geology of the mineral deposits il Ubehebe Peak quadrangle, Inyo County, California : Ca m: Div. Mines Special Rept. 42, p. 23. Melhase, John, 1936, A new occurrence of rare-earth mini j i California : Mineralogist, v. 4, no. 1, p. 11. Miller, W. J., 1931, Geologic sections across the southern en Nevada of California : Univ. California Dept. Geol. Sci ol v. 20, no. 9, p. 331-360. Miller, W. J., 1938, Pre-Cambrian and associated rock lei Twentynine Palms, California : Geol. Soc. America Bull. I no. 3, p. 417-446. Murdoch, Joseph, and Webb, R. W., 1948, Minerals of Cali lia California Div. Mines Bull. 136, 402 p. Olson, Jerry C, Shawe, D. R., Pray, L. C, and Sharp, W. I 4 a foreword by D. F. Hewett, 1954, Rare earth mineral (