Mine detail: Forest Hill District

Previously called 'HopeGreen SpringOronoSmall HopeYankee JimsGeorgia HillGray EaglePeckham HillTodd?s ValleyPond?s ChannelSan FranciscoExcelsiorBaltimoreIndependentJenny LindNew JerseyMausSmith PointBaker DivideParagonMayflowerDardanellesBlack HawkLive OakSpring GardenCentennial'

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Location

Lat / long: 39.02069, -120.81873

Resource(M)

Primary: Gold
Secondary: Platinum, Silver
Tertiary: Lead, Iron, Zinc, Copper, Indium
Ore: Gold
Gangue: Gravel, Quartz
Orebody form: Irregular; Tabular, lens
Discovery year: 1850

Production

Operation type: Surface-Underground
Deposit type: Stream placer; hydrothermal vein
Development status: Past Producer

Geology

Host rock:Valley Springs Formation, Calaveras Complex
Host type:Sand and Gravel,Rhyolite,Tuff,Slate,Serpentinite
Structure:Melones Fault Zone, Gillis Hill Fault Zone, Foresthill Fault, Volcano Canyon Fault, Melones Fault Zone.
Tectonic:Magmatic arc; narrow ocean basin
Alteration processes:None?Negligible - none described

References

DEP10310614
Reference{Deposit:: Averill, C. V., 1946, Placer mining for gold in California: California Division of Mines Bulletin 135, p. 377.}{Deposit:: Beard, J. S. and Day, H. W., 1987, The Smartville intrusive complex, Sierra Nevada, California: The core of a rifted volcanic arc: Geological Society of America Bulletin, v. 99, no. 6, p. 779-791.}{Deposit:: Brooks, E. R., 2000, Geology of a late Paleozoic island arc in the northern Sierra terrane, in Brooks, E. R. and Dida, L.T., editors, Field guide to the geology and tectonics of the northern Sierra Nevada, California Division of Mines and Geology Special Publication 122, p. 53-110.}{Deposit:: Browne, R. E., 1890, Ancient river beds of the Forest Hill Divide: California State Mining Bureau 10th Annual Report of the State Mineralogist, P. 435-465.}{Deposit:: Chandra, D. K., 1961, Geology and mineral deposits of the Colfax and Foresthill quadrangles, California: California Division of Mines Special Report 67, 50 p.}{Deposit:: Clark, L. D., 1960, Foothills fault system, western Sierra Nevada, California: Geological Society of America Bulletin, v. 71, p. 483-496.}{Deposit:: Clark, W. B., 1966, Gold, in Mineral resources of California: California Division of Mines and Geology Bulletin 191, p. 179-185.}{Deposit:: Clark, W. B., 1970 Gold districts of California: California Divisions of Mines and Geology Bulletin 193, p. 49-50.}{Deposit:: Day, H.W. and others, 1988, Metamorphism and tectonics of the northern Sierra Nevada, in Ernst, W. G., editor, Metamorphism and crustal evolution of the western United States (Rubey Volume VII): Prentice-Hall, Englewood Cliffs, New Jersey , p. 738-759.}{Deposit:: Dunn, R. L., 1888, Drift mining in California: California State Mining Bureau 8th Annual Report of the State Mineralogist, p. 736-770.}{Deposit:: Gilbert, G. K., 1917, Hydraulic mining debris in the Sierra Nevada: U.S. Geological Survey Professional Paper 105, 155 p.}{Deposit:: Hamilton, F., 1920, Placer County: California State Mining Bureau 17th Report of the State Mineralogist, p. 442-451.}{Deposit:: Hammond, J. H., 1889, The auriferous gravels of California: California State Mining Bureau 9th Report of the State Mineralogist, p. 105-138.}{Deposit:: Harwood, D.S., 1988, Tectonism and metamorphism in the northern Sierra terrane, northern California, in Ernst, W. G., editor, Metamorphism and crustal evolution of the western United States (Rubey Volume VII): Prentice-Hall, Englewood Cliffs, New Jersey, p. 764-788.}{Deposit:: Lindgren, W., 1900, Colfax folio, California: U. S. Geological Survey Atlas of the U. S., Folio 66, 10 p.}{Deposit:: Lindgren, W., 1911, The Tertiary gravels of the Sierra Nevada of California, U. S. Geological Survey Professional Paper 73, 226 pp.}{Deposit:: Logan, C. A., 1927, Placer County: California Division of Mines 23rd Report of the State Mineralogist, p. 235-279.}{Deposit:: Logan. C. A., 1936, Gold mines of Placer County: California Division of Mines 32nd Report of the State Mineralogist, p. 7-96.}{Deposit:: Logan, C. A., 1948, History of mining and milling methods in California, in Jenkins, O.P. and others, editors, Geologic guidebook along highway 49 - Sierran gold belt - The Mother Lode Country: California Division of Mines Bulletin 141, p. 31-34.}{Deposit:: Merwin, R. W., 1968, Gold resources in the Tertiary gravels of California: U.S. Bureau of Mines Technical Progress Report 3, 14 p.}{Deposit:: Saucedo, G. J. and Wagner, D. L., 1992, Geologic map of the Chico Quadrangle: California Division of Mines and Geology Regional Map Series Map No. 7A, scale 1:250,000.}{Deposit:: Wagner, D. L. and others, 1987, Geologic map of the Sacramento Quadrangle: California Division of Mines and Geology Regional Map Series Map No. 1A, scale 1:250,000.}{Deposit:: Waring, C. A., 1917, Placer County: California State Mining Bureau 15th Report of the State Mineralogist, p. 309-399.}
ReporterDowney, Cameron I. (Higgins, Chris, T.), Schruben, Paul G.