Unnamed (on western Nakchamik Island)

The Unnamed (on western Nakchamik Island) is a copper 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

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.

Site Name

Primary: Unnamed (on western Nakchamik Island)

Commodity

Primary: Copper
Secondary: Zinc
Secondary: Lead

Location

State: Alaska
District: Alaska Peninsula

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: Porphyry Cu

Orebody

Not available

Structure

Not available

Alterations

Alteration Type: L
Alteration Text: Country rocks are propylitically and sericitically altered. The area is marked by a large color anomaly.

Rocks

Name: Tonalite
Role: Associated
Age Type: Associated Rock
Age Young: Pliocene

Analytical Data

Not available

Materials

Ore: Chalcopyrite
Ore: Galena
Ore: Pyrite
Ore: Sphalerite
Gangue: Barite
Gangue: Quartz

Comments

Comment (Exploration): Status = Inactive

Comment (Deposit): Model Name = Porphyry copper (Cox and Singer, 1986, model 17)

Comment (Deposit): Other Comments = This site is on land selected by the Koniag Native Corporation.

Comment (Reference): Primary Reference = Cox and others, 1981

Comment (Workings): Workings / Exploration = Remnants of old mining equipment have been found at this prospect, indicating early exploration. The U.S. Geological Survey collected 16 rock samples in the 1970's (Yount and others, 1978). The highest metal values obtained were 1600 ppm copper, 130 ppm lead, and 260 ppm zinc. Cox and others (1981) report surface copper values at <0.2 percent.

Comment (Geology): Geologic Description = On Nakchamik Island, dacite plug domes intrude Oligocene and Eocene volcanic rocks of the Meshik Formation (Detterman and others, 1981). The prospect is marked by a large color anomaly. Closely-spaced quartz(?) veinlets containing abundant pyrite and chalcopyrite have been noted. Stream-sediment samples contain anomalous values in copper, lead, silver, and zinc and many contain barite. Cox and others (1981) report the grade of surface samples at <0.2 percent copper. Sixteen rock samples were collected in the 1970's by the U.S. Geological Survey (Yount and others, 1978). The highest values obtained were 1600 ppm copper, 130 ppm lead, and 260 ppm zinc.

Comment (Geology): Age = Tertiary.

References

Reference (Deposit): Cox, D.P., Detra, D.E., and Detterman, R.L., 1981, Mineral resource maps of the Chignik and Sutwik Island quadrangles, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF- 1053-K, 2 map sheets, scale 1:250,000.

Reference (Deposit): Young, L.E., St. George, P., and Bouley, B., 1997, Porphyry copper deposits in relation to the magmatic history and palinspastic restoration of Alaska, in Goldfarb, R.J., and Miller, L.D., (eds.), Mineral deposits of Alaska: Economic Geology Monograph 9, p. 306-333.

Reference (Deposit): Detterman, R.L., Miller, T.P., Yount, M.E., and Wilson, F.H.,1981, Geologic map the Chignik and Sutwik Island quadrangles Alaska: U.S. Geologic Survey Miscellaneous Investigations Series Map I- 1229, 1 map sheet, scale 1:250,000.

Reference (Deposit): Yount, M.E., Cooley, E.F., and O'Leary, R.M., 1978, Sample location map, analytical data, and statistical summary of analyses of rock samples, Chignik and Sutwik Island quadrangles, Alaska: U.S. Geological Survey Open-File Report 78-557, l sheet, scale l:250,000.

Reference (Deposit): Wilson, F.H., 1980, Late Mesozoic and Cenozoic tectonics and age of porphyry copper prospects, Chignik and Sutwik Island quadrangles, Alaska Peninsula: U.S. Geological Survey Open-File Report 80-543, 94 p., 5 sheets, scales 1:250,000 and 1 inch = 1,000 feet.

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.