Apex

Prospect, Undetermined

Commodities and mineralogy

Main commodities Ag; Au; Cu
Ore minerals arsenopyrite; chalcopyrite
Gangue minerals quartz

Geographic location

Quadrangle map, 1:250,000-scale SI
Quadrangle map, 1:63,360-scale A-4
Latitude 57.0138
Longitude -135.1895
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Apex prospect is at an elevation of about 600 feet on the west side of Silver Bay opposite Bear Cove. The prospect is 0.1 mile east of the center of sec. 14, T. 56 S., R. 64 E. It is location P-120 of Bittenbender and others (1999) and MAS no. 0021140162 (U.S. Bureau of Land Management, 2002). The location is accurate within 0.2 mile.

Geologic setting

Geologic description

The rocks in the vicinity of the Apex prospect are part of the Jurassic and Cretaceous, Sitka Graywacke that consists mainly of graywacke and argillite (Loney and others, 1975). The location of the Apex prospect is shown on a map by Becker (1897) but it is not described in the text. The prospect was examined by Bittenbender and others (1999) who found abundant quartz float in a creek and a quartz breccia vein along a fault. The only working was an 8-foot adit along the fault. The vein strikes N30W, dips 75SW, is up to 1.7 feet thick, and contains arsenopyrite and trace chalcopyrite. A sample across the vein contained 270 parts per million (ppm) copper, 44 ppm arsenic, and 0.2 ppm silver. A select sample of the quartz float contained 920 ppm copper and 1.0 ppm silver. The highest gold values in any of the samples was 40 parts per billion.
Geologic map unit (-135.191264065828, 57.0134366033461)
Mineral deposit model Low-sulfide gold-quartz vein (Cox and Singer, 1986; model 36a).
Mineral deposit model number 36a
Age of mineralization Jurassic or younger based on the age of the host rock.

Production and reserves

Workings or exploration The only working is an old 8-foot adit.
Indication of production None
Production notes Probably none.

References

References

Bittenbender, P., Still, J.C., Maas, K., and McDonald, M., Jr., 1999, Mineral resources of the Chichagof and Baranof Islands area, southeast Alaska: Bureau of Land Management, BLM-Alaska Technical Report 19, 222 p.
U.S. Bureau of Land Management, 2002, Alaska mineral locations database report (Sitka quadrangle), July 2, 2002, 205 p. [http://imcg.wr.usgs.gov/dem.html]
Reporters Donald Grybeck (U.S. Geological Survey)
Last report date 5/5/2005