Colorado · Fremont County
Past Producer

Cotopaxi Mine

Fremont County, Colorado, United States
CopperZincGoldSilverLeadIronMolybdenumTungsten
⌖ Show on mapUSGS source ↗
Commodities
PrimaryCopper, Zinc
SecondaryGold, Silver, Lead
TertiaryIron, Molybdenum, Tungsten
Commodity typeM
Deposit
Model271: Stratabound Precambrian sulfide, Colorado and Wyoming
Deposit sizeS
WorkingsUnknown, Underground
Orebody formLENSOID
Ore controlLeucocratic Bands, Amphibolite
Materials
Ore mineralsAnglesite, Bornite, Chalcopyrite, Chrysocolla, Covellite, Cuprite, Gahnite, Galena, Goethite, Gold, Hematite, Limonite, Magnetite, Malachite, Molybdenite, Pyrite, Pyrrhotite, Scheelite, Silver, Sphalerite, Tetrahedrite
GangueActinolite, Amazonstone, Anthophyllite, Biotite, Calcite, Clinohumite, Cordierite, Diopside, Garnet, Gypsum, Hornblende, Phlogopite, Quartz, Thulite
Geology
Host rockAmphibolite,Biotite Gneiss,Schist,Gneiss,Skarn (Tactite) · Biotite gneiss and migmatitic gneiss
Associated rockGranodiorite
StructureCotopaxi Fault; Subsidiary North-, Nne-, And Ew-Trending Faults, Thirtynine Mile Volcanic Field
AlterationSurficial Oxidation, gahnite mineralization present (zinc spinel)
Economic & production
Development statusPast Producer
First production1875
Last production1967
Discovery year1875
Identification
Deposit ID10087764
MRDS IDD009464
Alternate namesGumaer Mine, Cotopaxi Lode, Fannie Lode, Fannie Mill
RegionNA
Data scoreA
Coordinates38.38001, -105.69836
References
VANDERWILT, J.W., 1947, MINERAL RESOURCES OF COLORADO: COLORADO MINERAL RESOURCES BOARD, P. 83-85.TAYLOR, R.B., SCOTT, G.R., WOBUS, R.A., EPIS, R.C., 1975, RECONNAISSANCE GEOLOGIC MAP OF THE COTOPAXI 15-MINUTE QUADRANGLE, FREMONT AND CUSTER COUNTIES, COLORADO: USGS MAP I-900, 1:62,500.LINDGREN, W., 1908, NOTES ON COPPER DEPOSITS IN CHAFFEE, FREMONT, AND JEFFERSON COUNTIES, COLORADO: USGS BULLETIN 340, P. 157-174.HEINRICH, E.W., 1981, PRECAMBRIAN TUNGSTEN AND COPPER-ZINC SKARN DEPOSITS OF SOUTH-CENTRAL COLORADO: CGS RESOURCE SERIES 21, 115 P.6) HARRER, C.M. AND TESCH, W.J., JR., 1959, RECONNAISSANCE OF IRON OCCURRENCES IN COLORADO: USBM INFORMATION CIRCULAR 7918, 82 P.SALOTTI, C.A., 1965, MINERALOGY AND PARAGENESIS OF THE COTOPAXI, COLORADO COPPER-ZINC SKARN DEPOSIT: AMERICAN MINERALOGIST, V. 50, NO. 9, P. 1179-1212.COKER, R.J., 1982, MINERAL RESOURCES OF THE ARKANSAS CANYON PLANNING UNIT WITH SPECIAL EMPHASIS ON THE FORMER GRAPE CREEK WILDERNESS STUDY AREAS AND THE MCINTYRE HILLS WILDERNESS STUDY AREA: US BLM MINERAL REPORT, P. 50-52.Sheridan, D.M., and Raymond, W.H., 1984. Preliminary report on the geology of the Sedalia mine are and its Proterozoic deposits of base-metal sulfides and gahnite, Chaffee County, Colorado: U.S. Geological Survey Open-File Report 84-0800, 27 p., 1 plate.Sheridan, D.M., and Raymond, W.H., 1984, Precambrian deposits of zinc-copper-lead sulfides and zinc spinel (gahnite) in Colorado: U.S. Geological Survey Bulletin 1550, 31 p.Sheridan, D.M., Raymond, W.H., Taylor, R.B., and Hasler, J.W., 1990, Metallogenic map of stratabound exhalative and related occurrences in Colorado: U.S. Geological Survey Miscellaneous Investigations Series Map I-1971, scale 1:1,000,000Heimann, Adriana, 2002, The composition of zinc-rich spinels associated with metamorphosed massive sulfide deposits - a reexamination: Society of Economic Geologists Abstracts, 2002 Denver Annual Meeting.COLORADO DIVISION MINES INSPECTION RECORDS; COKER, 1982