California · Nevada County
Past Producer
Idaho - Maryland Mine
Nevada County, California, United States
Gold Silver
Land & claims · BLM · live
Loading land status…
Surface manager + active mining claims at this point, live from BLM. The "open to location" notes are a general 1872-Mining-Law guide, not BLM output — decision-support only; verify with BLM MLRS and on the ground before staking or entry.
Commodities
PrimaryGold
SecondarySilver
Commodity typeMetallic
Deposit
Deposit typeHydrothermal vein
Model273: Low-sulfide Au-quartz vein
Orebody formTabular
Ore controlMineralization occurs as erratic shoots within mesothermal gold-bearing quartz deposited within fracture zones.
Materials
Ore mineralsGold, Pyrite, Galena
GangueQuartz, Calcite, Chalcopyrite, Sphalerite
Geology
Host rockGranodiorite,Diabase,Serpentinite
StructureWolf Creek Fault Zone, Gillis Hill Fault, Melones Fault Zone
Tectonic settingMagmatic arc
AlterationAnkeritic, sericitic, and pyritic replacement of wall rocks adjacent to veins
Economic & production
Development statusPast Producer
Discovery year1865
Community notes
No community notes yet. Be the first to add field knowledge, history, or access tips.
Contribute
References
Clark, W.B., 1970, Gold districts of California: California Division of Mines and Geology Bulletin 191, p. 53.Johnston, W.G., Jr., 1940, The gold quartz veins of Grass Valley, California: U.S. Geological Survey Professional Paper 194, 101 p.Koschmann, A.H., and Bergendahl, M.H., 1968, Gold-producing districts of the United States: U.S. Geological Survey Professional Paper 610, 283 p.Lindgren, W., 1896a, Geologic atlas of the United States - Nevada City Special Folio: U.S. Geological Survey Folio 29.Lindgren, W., 1896b, Gold-quartz veins of Nevada City and Grass Valley: Seventeenth Annual Report of the U.S. Geological Survey, Part 2, p. 1-262MacBoyle, E.M., 1919, Mines and mineral resources of Nevada County: Sixteenth Annual Report of the State Mineralogist, California State Mining Bureau, p. 1-270.Additional information on the Idaho - Maryland Mine is contained in File No. 331-9392 (CGS Mineral Resources Files, Sacramento)
Identification
Deposit ID10310630
RegionNA
Data scoreB
Coordinates39.22339, -121.03843
Base: USGS MRDS (public domain, frozen 2011). Community notes © their authors, CC-BY. Land data live from BLM.