Unnamed (near St. James Bay) (ARDF #JU075) Cu, Zn

Unnamed (near St. James Bay)

Occurrence, Inactive

Commodities and mineralogy

Main commodities	Cu; Zn
Ore minerals	pyrite
Gangue minerals	calcite; quartz

Geographic location

Quadrangle map, 1:250,000-scale	JU
Quadrangle map, 1:63,360-scale	C-5
Latitude	58.6193
Longitude	-135.3602
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This occurrence is about 4 miles west of St. James Bay. It is at an elevation of approximately 2,000 feet, near the terminus of a glacier at the head of a creek draining into St. James Bay. It is in the SW1/4 NW1/4 section 33, T. 37 S., R. 61 E. of the Copper River Meridian. The location is accurate.

Geologic setting

Geologic description This occurrence is in Silurian graywacke, turbidite, and limestone of the Point Augusta Formation (Brew and Ford, 1985). The deposit consists of pods and stringers of pyrite in siliceous argillite and in quartz veins. A U.S. Bureau of Mines sample of a quartz-calcite vein contained up to 4,000 ppm copper and 1,600 ppm zinc (Clough and Redman, 1989). The general area is underlain by metamorphosed Silurian and Devonian clastic rocks, limestone, and volcanic units; Permian limestone and siltstone; and small plutons of Tertiary and Cretaceous granodiorite (Brew and Ford, 1985).
Geologic map unit	(-135.362015103916, 58.6189690741167)

Geologic description

This occurrence is in Silurian graywacke, turbidite, and limestone of the Point Augusta Formation (Brew and Ford, 1985). The deposit consists of pods and stringers of pyrite in siliceous argillite and in quartz veins. A U.S. Bureau of Mines sample of a quartz-calcite vein contained up to 4,000 ppm copper and 1,600 ppm zinc (Clough and Redman, 1989). The general area is underlain by metamorphosed Silurian and Devonian clastic rocks, limestone, and volcanic units; Permian limestone and siltstone; and small plutons of Tertiary and Cretaceous granodiorite (Brew and Ford, 1985).

Geologic map unit

(-135.362015103916, 58.6189690741167)

Production and reserves

Workings or exploration	Only surface sampling.
Indication of production	None

References

References Brew, D.A., and Ford, A.B., 1985, Preliminary reconnaissance geologic map of the Juneau, Taku River, Atlin, and part of the Skagway 1:250,000 quadrangles, southeastern Alaska: U.S. Geological Survey Open-File Report 85-395, 23 p., 2 sheets, scale 1:250,000. Clough, A.H., and Redman, E.C., 1989, Bureau of Mines mineral investigations in the Juneau mining district, Alaska, 1984-1988, Volume 2, Detailed mine, prospect, and mineral occurrence descriptions, Section C, West Lynn Canal subarea: U.S. Bureau of Mines of Mines Special Publication, 44 p.
Reporters	J.C. Barnett and L.D. Miller (Juneau, Alaska )
Last report date	12/15/2001