Alaska
Prospect

Unnamed (Bruce Hills)

Alaska, United States
MolybdenumCopperZincLeadSilver
⌖ Show on mapUSGS source ↗
Commodities
PrimaryMolybdenum, Copper
SecondaryZinc, Lead, Silver
Commodity typeM
Deposit
Model53: Porphyry Cu54: Porphyry Cu (North America)
Materials
Ore mineralsChalcopyrite, Galena, Hematite, Malachite, Molybdenite, Molybdite, Pyrrhotite, Sphalerite
GangueChlorite, Limonite, Montmorillonite, Quartz
Geology
AlterationK-feldspar occurs as a secondary mineral in and near quartz veins, and the host granodiorite is anomalously rich in K-feldspar, particularly south and east of the deposit (Kimball and others, 1978, p. C306). Feldspathization was noted elsewhere in the area. Montmorillonite is developed locally. The deposit itself is propylitically altered, with chlorite replacing primary mafic minerals.
Economic & production
Development statusProspect
Identification
Deposit ID10308917
MRDS IDA013172
RegionNA
Data scoreC
Coordinates58.98273, -136.34311
References
Rossman, Darwin, 1963, Geology of the eastern part of the Mount Fairweather quadrangle, Glacier Bay, Alaska: U.S. Geological Survey Bulletin 1121-K, p. K1-K57.MacKevett, E.M., Jr., Brew, D.A., Hawley, C.C., Huff, L.C., and Smith, J.G., 1971, Mineral resources of Glacier Bay National Monument, Alaska: U.S. Geological Survey Professional Paper 632, 90 p., 12 plates, scale 1:250,000.Moerlein, G.A., 1971, Report of examination of Bruce Hills copper-molybdenum deposit, Mt. Fairweather D-2 quadrangle: (Unpublished report available at U.S. Bureau of Land Management Library at Juneau, Alaska).Brew, D.A., Johnson, B.R., Grybeck, D., Griscom, A., Barnes, D.F., Kimball, A.L., Still, J.C., and Rataj, J.L., 1978, Mineral resources of the Glacier Bay National Monument Wilderness Study Area, Alaska: U.S. Geological Survey Open-File Report 78-494, 670 p.Kimball, A.L., Still, J.C., and Rataj, J.L., 1978, Mineral resources, in Brew, D. A., and others, Mineral resources of the Glacier Bay National Monument wilderness study area, Alaska: U.S. Geological Survey Open-File Report 78-494, p. C1-C375.Cobb, E.H., 1972, Metallic mineral resources map of the Mount Fairweather quadrangle, AK: U.S. Geological Survey Miscellaneous Field Study Map MF-436, 1 sheet, scale 1:250,000.