Description
Big Seven Mining Co.
Commodities
PrimarySilver, Gold
SecondaryCopper, Lead
TertiaryMolybdenum, Zinc
Commodity typeM
Deposit
Deposit typePolymetallic veins
Model85: Polymetallic veins
Deposit sizeY
WorkingsUnderground
Orebody formTABULAR
Ore controlNortheast-Trending Fractures, Snow Creek Porphyry; Vein Narrow In Pinto Diorite, Wider And Richer In Gneiss
Materials
Ore mineralsChalcopyrite, Freibergite, Galena, Molybdenite, Proustite, Pyrite, Sphalerite
Geology
Host rockDiorite,Quartzite,Gneiss,Rhyolite · Belt, Neihart Quartzite;Gneiss And Schist
Associated rockDiorite,Rhyolite · Snow Creek Porphyry-Pluton And Dikes Of Rhyolite Porphyry;Pinto Diorite-Large Phenocrysts Of Feldspar & Hornblende
StructureZone Of Igneous Intrusions Covering Over 800 Square Km., Domal Uplift Caused By Intrusion Of Snow Creek Porphyry, Northeast-Trending Fractures And Faults
Tectonic settingRocky Mountain Foreland
AlterationSericitization & Silicification
Economic & production
Development statusPast Producer
Discovery year1892
Identification
Deposit ID10071381
MRDS IDW014726
RegionNA
Data scoreA
Coordinates46.94908, -110.70556
References
ROBERTSON, A. F., 1951, MINES & MINERAL DEPOSITS - CASCADE COUNTY, MONTANA, U.S. BUREAU MINES INF. CIRC. 7589.SCHAFER, P. A., 1935, GEOLOGY AND ORE DEPOSITS - NEIHART MINING DISTRICT, CASCADE CO., MONTANA, MT BUREAU OF MINES & GEOLOGY MEM. 13KLEINKOPF, M. D., WITKIND, I. J., AND KEEFER, W. R., 1972, AEROMAGNETIC, BOUGUER GRAVITY, AND GENERLIZED GEOLOGIC MAPS OF THE CENTRAL PART OF THE LITTLE BELT MOUNTAINS, MONTANA: U.S. GEOLOGICAL SURVEY MAP GP-837WEED, W.H., 1900, THE GEOLOGY OF THE LITTLE BELT MOOUNTAINS, MONTANA: U.S. GEOLOGICAL SURVEY TWENTIETH ANNUAL REPORT, PART 3, P. 437-439.ROBERTSON, 1951, U.S.B.M. INF. CIRC. 7589