HET

Occurrences, Probably inactive

Alternative names

CPY

Commodities and mineralogy

Main commodities Cu
Ore minerals chalcopyrite

Geographic location

Quadrangle map, 1:250,000-scale CR
Quadrangle map, 1:63,360-scale A-2
Latitude 55.19397
Longitude -132.52139
Nearby scientific data Find additional scientific data near this location
Location and accuracy The HET and CPY occurrences are about 0.6 mile northeast of the head of Hetta Lake at about 1,400 to 1,500 feet in elevation. They are about 0.6 mile west-northwest of the center of section 18, T. 77 S, R. 86 E.

Geologic setting

Geologic description

The HET and CPY occurrences are near a thrust contact between outcrops of hornfels (Herreid and others, 1978; Maas and others, 1991, 1995). A Cretaceous granodiorite intrusion crops out just to the south on the north side of Hetta Lake. The occurrences consist of chalcopyrite-bearing float. The highest copper value in 6 samples was 1,251 parts per million copper; gold was not detected.
Geologic map unit (-132.523057354717, 55.1936154691833)
Mineral deposit model Copper skarn? (Cox and Singer, 1986; model 18b).
Mineral deposit model number 18b?
Age of mineralization Probably Cretaceous.
Alteration of deposit Development of hornfels.

Production and reserves

Workings or exploration Only surface sampling by government geologists.
Indication of production None

Additional comments

These occurrences are on land whose surface and subsurface rights have been conveyed to, or are under application for transfer to, the Sealaska Corporation.

References

References

Glavinovich, P.S., 1987, Sealaska Corporation Minerals Breifing Book, December 1987: Sealaska Corporation, 40 p. and plates. (Unpublished report held by Sealaska Corporation, Juneau, Alaska).
Hedderly-Smith, D.A., 1997, Results of 1996 reconnaissance sampling at Hetta Lake-Sealaska minerals reconnaissance project: Sealaska Corporation, 17 p.with addendum. (Unpublished report held by the Sealaska Corporation, Juneau, Alaska.)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).
Reporters D.J. Grybeck (Applied Geology)
Last report date 5/1/2004