Corbin

Mine, Active?

Commodities and mineralogy

Main commodities Ag; Au; Cu; Zn
Ore minerals chalcopyrite; pyrite; sphalerite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale CR
Quadrangle map, 1:63,360-scale A-2
Latitude 55.23078
Longitude -132.65045
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Corbin Mine is shown on the 1:63,360-scale USGS topographic map. It is at sea level about 0.3 mile southeast of Corbin Point, and about 0.4 mile west-northwest of the southeast corner of section 33, T. 76 S., R. 84 E.

Geologic setting

Geologic description

The Corbin Mine was discovered between 1900 and 1903. By 1913, it was developed by a 100-foot shaft (now flooded) with crosscuts and drifts from it, 337-foot and 25-foot adits, and surface trenches (Wright and Wright, 1908; Bufvers, 1967; Maas and others, 1991, 1995; Hedderly-Smith, 1999 [Inventory]). A little ore was shipped from 1905 to 1913 but there has been no mining since. In 1991, geologists from the Sealaska Corporation conducted several geophysical surveys in the area. American Copper and Nickel Company leased the property and mapped the area in 1992; they drilled three holes in 1993. The first hole was lost, the second did not cut mineralization, and the third cut two of the three known mineralized layers.
The Corbin deposit is a volcanogenic massive sulfide deposit that consists of three layers or lenses of mineralization one to two feet thick (Wright and Wright, 1908; Herreid and others, 1978; Maas and others, 1991, 1995; Hedderly-Smith, 1999 [Inventory]). One of the layers extended for at least 250 feet in the underground workings. The host rocks are quartz-sericite schist, chlorite schist, and phyllite of the Wales Group of Late Proterozoic and Cambrian age (Everlein and others, 1983; Brew, 1996; Slack and others, 2002). The layers consist mainly of pyrite, chalcopyrite, and sphalerite in siliceous gangue. Recent detailed geochemical and isotopic work by Slack and others (2002) confirm that the deposit is of Late Proterozoic or Cambrian age. The ore mined from 1905 to 1913 contained about $3.00 in gold and silver at prices current then. A 4-foot sample across one of the lenses exposed in an adit contained 3.25 percent copper, 4.15 percent zinc, 24.0 parts per million silver, and 1,395 parts per billion gold (Maas and others, 1991, 1995). Grab samples of massive sulfides from the dump contained up to 9 percent copper, 21 percent zinc, 2.7 ounces of silver per ton, and 0.11 ounce of gold per ton (Hedderly-Smith, 1999 [Inventory]).
Geologic map unit (-132.652104414978, 55.2304287966198)
Mineral deposit model Kuroko massive sulfide (Cox and Singer, 1986; model 28a).
Mineral deposit model number 28a
Age of mineralization Probably contemporaneous with the deposition of the protoliths of the metamorphic host rocks, which are part of the Wales Group of Late Proterozoic and Cambrian age.

Production and reserves

Workings or exploration The Corbin Mine was discovered between 1900 and 1903. By 1913, it was developed by a 100-foot shaft (now flooded) with crosscuts and drifts from it, 337-foot and 25-foot adits, and surface trenches (Wright and Wright, 1908; Bufvers, 1908; Maas and others, 1991 and 1995; Hedderly-Smith, 1999 [Inventory]). American Copper and Nickel Company leased the property and mapped the area in 1992; they drilled three holes in 1993.
Indication of production Yes; small
Reserve estimates None.
Production notes There were several small shipments of ore from 1905 to 1913.

Additional comments

The Corbin Mine is on land that has been conveyed to the Sealaska Corporation, who hold the surface and subsurface rights, or the land is under application for transfer to them.

References

MRDS Number A010071

References

Hedderly-Smith, D.A., 1990, Report of the 1989 field season - Sealaska Mineral Reconnaissance Project: Sealaska Corporation, 58 p. (Unpublished report held by the Sealaska Corporation, Juneau, Alaska.)
Hedderly-Smith, D.A., 1991, Report of the 1990 field season-Sealaska Mineral Reconnaissance Project: Sealaska Corporation: Sealaska Corporation, 2 vols., 180 p., 13 plates. (Unpublished report held by the Sealaska Corporation, Juneau, Alaska.)
Hedderly-Smith, D.A., 1992, Report of the 1991 field season - Sealaska Mineral Reconnaissance Project: Sealaska Corporation, 2 vols., 225 p. 23 plates. (Unpublished report held by the Sealaska Corporation, Juneau, Alaska.)
Hedderly-Smith, D.A., 1995, Report of the 1994 work in the Kael-Dolomi area-Sealaska minerals project: Sealaska Corporation, 36 p. plus appendices (Unpublished report held by the Sealaska Corporation, Juneau, Alaska.)
Hedderly-Smith, D.A., 1999, Inventory of metallic mineral prospects, showings and anomalies on Sealaska lands, 1988 through 1998: Sealaska Corporation, Juneau, Alaska, 217 p. (internal report held by Sealaska Corporation, Juneau, Alaska).
Roppel, Patricia, 1991, Fortunes from the earth: Manhattan, Kansas, Sunflower University Press, 139 p.
Slack, J.F., Shanks, W.C. III, Karl, S.M., Ridley, W.I., and Bittenbender, P.E., 2002, Geochemical and sulfur isotope compositions of Late Proterezoic and early Paleozoic volcanogenic massive sulfide deposits, Prince of Wales Island and vicinity, southeastern Alaska (abs.): Geological Society of America, Abstracts with Programs, v. 34 (6), p. 113.
Reporters D.J. Grybeck (Applied Geology)
Last report date 5/1/2004