Marble Copper

The Marble Copper 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: Marble Copper

Commodity

Primary: Copper
Secondary: Gold
Secondary: Lead
Secondary: Silver
Secondary: Zinc

Location

State: Alaska
District: Ketchikan

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: Local oxidation of copper minerals.

Rocks

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

Analytical Data

Not available

Materials

Ore: Chalcopyrite
Ore: Malachite
Gangue: Calcite

Comments

Comment (Workings): Workings / Exploration = The prospect was privately explored sometime before 1972 by a shallow opencut, but there was no evidence in 1973 that any claims had been staked. A 22-inch-long channel sample of the most heavily copper-stained part of the marble-skarn zone assayed up to 0.7% Cu, 150 ppm Pb, 300 ppm Zn, 30 ppm Ag, and 3.5 ppm Au (Berg and others, 1977, fig. 33, spl. no. 2K009). Adjacent channel samples showed much lower assay values, and a chip sample of a second band of marble northeast of the marble-skarn zone showed only traces of copper.

Comment (Commodity): Gangue = calc-silicate minerals

Comment (Geology): Age = Probably Cretaceous or younger.

Comment (Reference): Primary Reference = Berg and others, 1977

Comment (Deposit): Model Name = Cu skarn (Cox and Singer, 1986; model 18b)

Comment (Deposit): Other Comments = Prospect is in Misty Fiords National Monument Wilderness.

Comment (Geology): Geologic Description = The country rocks in the area of the Marble Copper prospect are Tertiary or Cretaceous foliated granodiorite and quartz diorite of the Coast Range batholith, and paragneiss and minor marble that form metamorphic roof pendants, screens, and inclusions in the batholith (Berg and others, 1977, p. 120-121; Berg and others, 1988). The metamorphic rocks represent marine strata that underwent high-grade regional metamorphism in Cretaceous or Tertiary time. The premetamorphic age of the strata is uncertain, but they probably are mainly Paleozoic and may be as old as Precambrian (Berg and others, 1988, p. 26; Gehrels and others, 1990; Crawford and others, in press).? the deposit consists of chalcopyrite and malachite in a marble-skarn zone in a paragneiss roof pendant in gneissic diorite and quartz diorite (Berg and others, 1977, p. 120-121 and fig. 33). The marble-skarn zone is about 20 feet wide, and it adjoins a zone of paragneiss and subordinate marble and skarn about 60 feet wide. the calc-silicate minerals in the skarn are not described, but their green color (fig. 33, spl. no. 2K008) suggests that they include diopside. A 22-inch-long channel sample of the most heavily copper-stained part of the marble-skarn zone assayed up to 0.7% Cu, 150 ppm Pb, 300 ppm Zn, 30 ppm Ag, and 3.5 ppm Au (Berg and others, 1977, fig. 33, spl. no. 2K009). Adjacent channel samples showed much lower assay values, and a chip sample of a second band of marble northeast of the marble-skarn zone showed only traces of copper. The prospect was explored sometime before 1972 by a shallow opencut, but there was no evidence in 1973 that any claims had been staked.

References

Reference (Deposit): Berg, H.C., Elliott, R.L., Smith, J.G., Pittman, T.L., and Kimball, A. L., 1977, Mineral resources of the Granite Fiords wilderness study area, Alaska, with a section on aeromagnetic data by Andrew Griscom: U.S. Geological Survey Bulletin 1403, 151 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.

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): Gehrels, G.E., McClelland, W.C., Samson, S.D., Patchett, P.J., and Jackson, J.L., 1990, Ancient continental margin assemblage in the northern Coast Mountains, southeast Alaska and northwest Canada: Geology, v. 18, p. 208-211.

Reference (Deposit): Crawford, M.L., Crawford, W.A., and Gehrels, G.E., 2000, Terrane assembly and structural relationships in the eastern Prince Rupert quadrangle, British Columbia, in H.H. Stowell and W.C.McClelland, eds., Tectonics of the Coast Mountains, southeastern Alaska and British Columbia: Boulder, Colorado, Geological Society of America Special Paper 343, p. 1-21.?

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.