|Quadrangle map, 1:250,000-scale||CR|
|Quadrangle map, 1:63,360-scale||A-1|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The Friendship prospect is just above the shoreline on the west side of the South Arm of Cholmondeley Sound, about 2.4 miles southwest of its mouth. It is about 0.4 mile south-southwest of the center of section 4, T. 77 S., R. 87 E. The Friendship prospect is sometimes described together with the Ruby Tuesday prospect (CR169) about 0.4 mile to the west.|
Geologic descriptionThe Friendship prospect has been known since before 1902 (Brooks, 1902) but little work has been done on it since then. The workings consist of a flooded pit and a shaft about 15 feet deep (Maas and others, 1991). The rocks in the vicinity consist of marble and greenschist of the Wales Group of Late Proterozoic and Cambrian age (Herreid and others, 1978). As described by Maas and others (1991), the deposit consists of a quartz-calcite vein 1.1 to 3.8 feet thick, with chalcopyrite, azurite, and malachite. One wall of the vein is marble, the other is felsic schist. The vein is along a shear zone that strikes N20-30E and has a steep dip. Seven samples contained 2,574 parts per million (ppm) to 0.456 ounce of gold per ton, and several contained more than 2 percent copper. The highest gold value in a 3.6-foot sample of the vein was 0.456 ounce per ton; the highest copper value in a 1-foot sample was 3.91 percent. There was negligible silver, lead, or zinc.
|Geologic map unit||(-132.31546242842, 55.2177132752191)|
|Mineral deposit model||Calcite-quartz vein with copper minerals.|
|Workings or exploration||The workings consist of a flooded pit and a shaft about 15 feet deep.|
|Indication of production||None|
Brooks, A.H., 1902, Preliminary report on the Ketchikan mining district, Alaska, with an introductory sketch of the geology of southeastern Alaska: U.S. Geological Survey Professional Paper 1, 120 p.
Cobb, E. H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Craig quadrangle, Alaska: U.S. Geological Survey Open-File Report 78-869, 262 p.
Herreid, Gordon, Bundtzen, T.K., and Turner, D.L., 1978, Geology and geochemistry of the Craig A-2 quadrangle, Prince of Wales Island, southeastern Alaska: Alaska Division of Geological and Geophysical Surveys Geologic Report 48, 49 p.
Kucinski, R.M., 1987, Geology and mineralization of the Ruby Tuesday claim block, Prince of Wales Island, southeast Alaska: Fairbanks, University of Alaska, M.Sc. thesis, 93 p.
Maas, K.M., Bittenbender, P E., and Still, J.C., 1995, Mineral investigations in the Ketchikan mining district, southeastern Alaska: U.S. Bureau of Mines Open-File Report 11-95, 606 p.
Maas, K.M., Still, J.C., Clough, A.H., and Oliver, L.K., 1991, Mineral investigations in the Ketchikan mining district, Alaska, 1990: southern Prince of Wales Island and vicinity: U.S. Bureau of Mines Open-File Report 33-91, 139 p., 12 sheets, scale 1:63,360.
|Reporters||D.J. Grybeck (Applied Geology)|
|Last report date||5/1/2004|