Unnamed (near Cape Addington)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Ag; Cu; Zn
Other commodities Pb
Ore minerals chalcopyrite; galena; pyrite; sphalerite
Gangue minerals epidote; garnet; quartz

Geographic location

Quadrangle map, 1:250,000-scale CR
Quadrangle map, 1:63,360-scale B-6
Latitude 55.45074
Longitude -133.8109
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is in a cliff face about 1.0 mile north-northeast of Cape Addington at the north end of a rocky beach. It is about 0.2 mile south of the center of section 14, T. 74 S., R. 76 E.

Geologic setting

Geologic description

This occurrence is at the contact between Silurian Heceta Limestone and a Cretaceous quartz monzonite and granodiorite pluton (Clark, 1970 [OF 420]; D.J. Grybeck, unpublished field notes and analyses, 1984). The pluton extends south to Cape Addington. Patches of calc-silicate gneiss and hornfels less than a few tens of feet thick mark the contact; locally there is quartz veining. The contact is also copper stained in places and there are disseminated and scattered small masses of sulfides, including chalcopyrite, sphalerite, galena, and pyrite. Almost all of the sulfides are within 10 feet of the contact and the mineralization is sparse. Selected samples contain up to several percent copper and zinc, and up to 50 parts per million silver.
Geologic map unit (-133.812576391118, 55.4503775954895)
Mineral deposit model Contact-metamorphic Ag-Cu-Zn deposit.
Age of mineralization In the contact of a Cretaceous granitic pluton.
Alteration of deposit Sparse skarn minerals at contact of granitic pluton and marble.

Production and reserves

Workings or exploration Only limited surface sampling during geologic mapping.
Indication of production None