Alaska Empire (ARDF #JU239) Ag, Au, Cu, Pb, Zn

Alaska Empire

Mine, Inactive

Map

KML

XML

GeoJSON

Alternative names

Williams
Hawk Inlet Mine

Commodities and mineralogy

Main commodities	Ag; Au; Cu; Pb; Zn
Ore minerals	chalcopyrite; galena; gold; pyrite; pyrrhotite; sphalerite
Gangue minerals	calcite; quartz

Geographic location

Quadrangle map, 1:250,000-scale	JU
Quadrangle map, 1:63,360-scale	A-3
Latitude	58.1841
Longitude	-134.7871
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	The Alaska Empire mine is at an elevation of approximately 1,000 feet on Mansfield Peninsula, 1.2 miles northwest of Hawk Inlet, 3.5 miles southeast of Mount Robert Barron, and 3 miles west of Young Bay. The site is at the mine symbol on the 1:63,360-scale topographic map, in the NW1/4SE1/4 section 33, T. 42 S., R. 65 E. of the Copper River Meridian. The location is accurate.

Geologic setting

Geologic description The deposit consists of 10 quartz-calcite veins, 2.5 feet to 50 feet thick, that strike north, dip steeply east, and can be traced for over 500 feet. The host rocks are greenschist, quartz-mica schist, and black graphitic phyllite (Townsend, 1941). One vein has been traced for over 2000 feet (Buddington, 1926). The hanging wall of the veins contains up to 5 percent pyrite. Some of the quartz is white, massive, and barren, and some is bluish and friable. The bluish veins contain pyrite, galena, sphalerite, chalcopyrite, and sparse pyrrhotite. All production has come from the Williams vein, which is up to 50 feet thick and has a vertical extent of at least 400 feet (Wells and others, 1986). The deposit was discovered before 1900 and has produced small amounts of gold intermittently since that time (Cobb, 1978 [OFR 78-374]). From 1931 to 1937, the Williams vein produced 17,767 tons of ore from a glory hole (Townsend, 1941). Other workings include a 353-foot tunnel, a 48-foot winze, several short crosscuts, open cuts, and surface trenches (Buddington, 1926). The rocks in the general area are mainly Ordovician and Devonian to Triassic, clastic units, mafic-intermediate volcanic rocks, and subordinate limestone. The bedded rocks are intruded and locally metamorphosed by Cretaceous granodiorite (Gehrels and Berg, 1994).
Geologic map unit	(-134.788888172826, 58.1837642970376)

Geologic description

The deposit consists of 10 quartz-calcite veins, 2.5 feet to 50 feet thick, that strike north, dip steeply east, and can be traced for over 500 feet. The host rocks are greenschist, quartz-mica schist, and black graphitic phyllite (Townsend, 1941). One vein has been traced for over 2000 feet (Buddington, 1926). The hanging wall of the veins contains up to 5 percent pyrite. Some of the quartz is white, massive, and barren, and some is bluish and friable. The bluish veins contain pyrite, galena, sphalerite, chalcopyrite, and sparse pyrrhotite. All production has come from the Williams vein, which is up to 50 feet thick and has a vertical extent of at least 400 feet (Wells and others, 1986). The deposit was discovered before 1900 and has produced small amounts of gold intermittently since that time (Cobb, 1978 [OFR 78-374]). From 1931 to 1937, the Williams vein produced 17,767 tons of ore from a glory hole (Townsend, 1941). Other workings include a 353-foot tunnel, a 48-foot winze, several short crosscuts, open cuts, and surface trenches (Buddington, 1926).

The rocks in the general area are mainly Ordovician and Devonian to Triassic, clastic units, mafic-intermediate volcanic rocks, and subordinate limestone. The bedded rocks are intruded and locally metamorphosed by Cretaceous granodiorite (Gehrels and Berg, 1994).

Geologic map unit

(-134.788888172826, 58.1837642970376)

Production and reserves

Workings or exploration	Discovered before 1900, workings include a glory hole, a 353-foot tunnel, a 48-foot winze, several short crosscuts, open cuts, and surface trenches.
Indication of production	Yes; small
Production notes	From 1931 to 1937, the Williams vein produced 17,767 tons of ore from a glory hole (Townsend, 1941).

References

MRDS Number	A012085
References Buddington, A.F., 1926, Mineral investigations in southeastern Alaska: U.S. Geological Survey Bulletin 783, p. 41-62. Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Juneau quadrangle, Alaska: U.S. Geological Survey Open-File Report 78-374, 155 p. Gehrels, G.E., and Berg, H.C., 1994, Geology of southeastern Alaska, in Plafker, George, and Berg, H. C., eds., The geology of Alaska: Geological Society of America, DNAG, The geology of North America, Vol. G-1, p. 451-467. Townsend, H.H., 1941, Report on Alaska Empire Mine, Hawk Inlet, Admiralty Island, Alaska: Alaska Division of Geological and Geophysical Surveys Miscellaneous Report 112-11, 27 p. Wells, D.E., Pittman, T.L., Brew, D.A. and Douglass, S.L., 1986, Map and description of the mineral deposits in the Juneau, Taku River, Atlin, and part of the Skagway quadrangles, Alaska: U.S. Geological Survey Open-File Report 85-717, 332 p., 1 sheet, scale 1:250,000.
Reporters	J.C. Barnett and L.D. Miller (Juneau, Alaska )
Last report date	12/15/2001