Mine detail: Old Eureka Mine

Previously called 'Amador Consolidated MineWolverine MineBadger MineHetty Green MineEureka MineHayward Mine'

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Location

Lat / long: 38.38788, -120.8

Resource(M)

Primary: Gold
Secondary: Silver
Ore: Gold, Pyrite, Arsenopyrite
Gangue: Quartz, Slate, Ankerite, Albite, Sphalerite
Orebody form: Tabular, pinch and swell
Discovery year: 1852

Production

Operation type: Underground
Deposit type: Hydrothermal vein
Development status: Past Producer

Geology

Host rock:Mariposa Formation
Host type:Slate,Greenstone
Structure:Melones Fault zone, Bear Mountains Fault zone, Melones Fault zone
Tectonic:Magmatic arc
Alteration processes:Wall rocks hydrothermally altered, having been partially to completely converted to ankerite, sericite, quartz, pyrite, arsenopyrite, chlorite, and albite. Locally, greenstone bodies adjacent to the quartz veins contain enough disseminated auriferous pyrite in large enough bodies to constitute low-grade ore.

References

DEP10310657
Reference{Deposit:: Clark, W. B., 1970, Gold districts of California: California Divisions of Mines and Geology Bulletin 193, p. 69-77.}{Deposit:: Carlson, D.W., and Clark, W.H., 1954, Mines and mineral resources of Amador County, California: California Division of Mines and Geology, 50th Report of the State Mineralogist, p. 173-177.}{Deposit:: Duffield, W.A. and Sharp, R.V., 1975, Geology of the Sierra foothills melange and adjacent areas, Amador County, California: U.S. Geological Survey Professional Paper 827, 30 p.}{Deposit:: Lambert, E.F., 1948, The geology of the Old Eureka Mine, Sutter Creek, Amador County, California: unpublished M.S. thesis, Univ. of California, Berkeley, 71 p.}{Deposit:: Logan, C.A., 1921, Mines and mineral resources, Amador County - Old Eureka Mine: California State Mining Bureau, 17th Annual Report of the State Mineralogist, p. 411.}{Deposit:: Logan, C.A., 1927, Amador County - Old Eureka Mine: California State Mining Bureau, 23nd Report of the State Mineralogist, p. 176-178.}{Deposit:: Logan, C.A., 1934, Mother Lode gold belt of California: California Division of Mines Bulletin 108, p. 101-104.}{Deposit:: Norman, L.A., 1939, Operations at the Old Eureka Mine: Mining Tech., v. 3, no. 6, p 1-15.}{Deposit:: Schweickert, R.A., Hanson, R.E., and Girty, G.H., 1999, Accretionary tectonics of the Western Sierra Nevada Metamorphic Belt in Wagner, D.L. and Graham, S.A., editors, Geologic field trips in northern California: California Division of Mines and Geology Special Publication 119, p. 33-79.}{Deposit:: Spiers, J., 1931, Mining methods and costs at the Central Eureka Mine, Amador County, California: Bureau of Mines Information Circular 6512, 13 pp.}{Deposit:: Storms, W.H., 1900, The Mother Lode region of California: California Mining Bureau Bulletin 18, p 64-65.}{Deposit:: Zimmerman, J.E., 1983, The Geology and structural evolution of a portion of the Mother Lode Belt, Amador County, California: unpublished M.S. thesis, University of Arizona, 138 p.}
ReporterDowney, Cameron (Higgins, Chris, T.), Schruben, Paul G.