Montana · Jefferson County
Past Producer

Gregory Mine

Jefferson County, Montana, United States
LeadSilverGoldCopperZincArsenic
⌖ Show on mapUSGS source ↗
Commodities
PrimaryLead, Silver
SecondaryGold, Copper, Zinc
TertiaryArsenic
Commodity typeM
Deposit
Deposit sizeS
WorkingsUnderground
Orebody formTABULAR
Ore controlVein In East-West Trending Altered Zone Which May Be A Poorly Developed Shear Zone
Materials
Ore mineralsChalcopyrite, Galena, Gold, Sphalerite
GanguePyrite, Quartz
Geology
Host rockQuartz Monzonite,Andesite
Associated rockQuartz Monzonite,Andesite · Butte Quartz Monzonite(Boulder Batholith);Elkhorn Mountain Volcanics
StructureBoulder Batholith, South-Trending Syncline In Elkhorn Mountains Volcanics, North-South Trending Faults West Of Mine; Roof Pendant Of Elkhorn Mountains Volcanics
Tectonic settingCordilleran Miogeosyncline
AlterationPyritized, Sericitized, Tourmalinized
Economic & production
Development statusPast Producer
First production1867
Discovery year1864
Identification
Deposit ID10071361
MRDS IDW014702
RegionNA
Data scoreB
Coordinates46.3899, -112.1156
References
MBMG BULL 16, P. 6, 44, 46, 50-1, 108.USGS PP 428, P. 35, 69, 71.USGS BULL 842, P. 245.USGS BULL 527, P. 117.MBMG BULL 16, P. 108. USGS PP 428, P. 71.