The Commonwealth is a molybdenum, zinc, copper, and gold mine located in Alaska.
About the MRDS Data:
All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.
Mine Info
Elevation:
Commodity: Molybdenum, Zinc, Copper, Gold
Lat, Long: 55.75, -130.22000
Map: View on Google Maps
Satelite View
MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.
Commonwealth MRDS details
Site Name
Primary: Commonwealth
Commodity
Primary: Molybdenum
Primary: Zinc
Primary: Copper
Primary: Gold
Location
State: Alaska
District: Hyder
Land Status
Not available
Holdings
Not available
Workings
Not available
Ownership
Not available
Production
Not available
Deposit
Record Type: Site
Operation Category: Prospect
Operation Type: Unknown
Years of Production:
Organization:
Significant:
Physiography
Not available
Mineral Deposit Model
Model Name: Skarn Cu
Orebody
Not available
Structure
Not available
Alterations
Alteration Type: L
Alteration Text: Weathered pyrrhotite gives a rusty color to the surface outcrop.
Rocks
Not available
Analytical Data
Not available
Materials
Ore: Sphalerite
Ore: Pyrrhotite
Ore: Molybdenite
Ore: Gold
Ore: Chalcopyrite
Gangue: Quartz
Comments
Comment (Reference): Primary Reference = Buddington, 1929 (B807)
Comment (Workings): Workings / Exploration = The prospect was explored in the early 1900s by opencuts, an 80-foot adit, and an 11-foot adit.
Comment (Geology): Geologic Description = The country rocks in the area of the presumed site are porphyritic quartz monzonite and granodiorite of the Eocene Davis River Pluton (Smith, 1977; Berg and others, 1988). According to Buddington (1929, p. 111-112), the Commonwealth prospect(s) lie within a narrow belt of metamorphosed sedimentary rocks that form a roof pendant within the quartz monzonite. The metamorphosed strata are several hundred feet thick and include interbedded quartzite, schist, and marble. A lamprophyre dike cuts the quartz monzonite and metasedimentary rocks. The quartzite, schist, and marble have been contact metamorphosed by the intrusion of the quartz monzonite and locally contain disseminations, seams, and small masses of quartz, garnet, epidote, pyroxene, tremolite, and small amounts of sulfide minerals. The sulfide minerals include pyrrhotite, sphalerite, chalcopyrite, and molybdenite, and a quartz stringer was reported to yield gold. The age of this contact metamorphic (skarn) deposit probably is Eocene, roughly contemporaneous with the emplacement of the Davis River Pluton. The prospect was explored in the early 1900s by an 80-foot adit and an 11-foot adit.
Comment (Commodity): Gangue = skarn minerals
Comment (Deposit): Model Name = Cu skarn (Cox and Singer, 1986; model 18b)
Comment (Deposit): Other Comments = Site is in Misty Fiords National Monument Wilderness.
Comment (Geology): Age = Eocene
References
Reference (Deposit): Berg, H.C., Elliott, R.L., and Koch, R.D., 1988, Geologic map of the Ketchikan and Prince Rupert quadrangles, southeastern Alaska: U.S. Geological Survey Mineral Investigations Series Map MF-1807,27 p., scale 1:250,000.
Reference (Deposit): Buddington, A.F., 1929, Geology of Hyder and vicinity, southeastern Alaska, with a reconnaissance of Chickamin River: U.S. Geological Survey Bulletin 807, 124 p.
Reference (Deposit): Smith, J.G., 1977, Geology of the Ketchikan D-1 and Bradfield Canal A-1 quadrangles, Alaska: U.S. Geological Survey Bulletin 1425, 49 p.
Reference (Deposit): Elliott, R.L., Berg, H.C., and Karl, Susan, 1978, map and table describing metalliferous and selected nonmetalliferous mineral deposits, Ketchikan and Prince Rupert quadrangles, Alaska: U.S. Geological Survey Open-file Report, 78-73-B,17 p., scale 1:250,000.
The Top Ten Gold Producing States
These ten states contributed the most to the gold production that built the West from 1848 through the 1930s. The Top Ten Gold Producing States.
