Main commodities | Cu; Pb; Zn |
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Other commodities | Ag; Au |
Ore minerals | arsenopyrite; bornite; chalcopyrite; marcasite; pyrite; specularite |
Gangue minerals | quartz |
Quadrangle map, 1:250,000-scale | CV |
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Quadrangle map, 1:63,360-scale | D-7 |
Latitude | 60.855 |
Longitude | -146.543 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | This site represents a mine and several prospects on the north side of inner Landlocked Bay. The map site is at an elevation of about 500 feet on a south-facing bluff above the bay. It is in the SW1/4 sec. 6, T. 12 S., R. 7 W., of the Copper River Meridian. The site is accurately located to within 1000 ft. This location is a combination of sites C-72, C-75, and C-80 of Jansons and others (1984), and site #14 of Cobb (1972: MF-392). |
Geologic descriptionThe mineral deposits at this site are in sheared mafic volcanic rocks of the Tertiary Orca Group (Nelson and others, 1985). They consist of 2-inch- to 4-ft.-wide lenses of massive sulfide accompanied by quartz gangue. Metalliferous minerals include arsenopyrite, bornite, chalcopyrite, marcasite, pyrite, and specularite. Early copper values reportedly were 11.4% to 12.5% Cu (Grant, 1906). Jansons and others (1984) report that a grab sample from the area contained 7.9% Cu. Chip samples contained 0.2%-3.9% Cu, along with a trace to 0.11 oz Au/ton. | |
Geologic map unit | (-146.544993772932, 60.8544515309008) |
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Mineral deposit model | Cyprus massive sulfide (Cox and Singer, 1986; model 24a) |
Mineral deposit model number | 24a |
Age of mineralization | Probably Tertiary based on the age of the host rock. |
Workings or exploration | The first discovery of copper (1897) in Prince William Sound was made in this area (Schrader, 1900). Capps and Johnson (1915) reported several adits, open cuts and a shaft. Early copper values reportedly were 11.4% to 12.5% Cu (Grant, 1906). Jansons and others (1984) report that a grab sample from the area contained 7.9% Cu. Chip samples contained 0.2%-3.9% Cu, along with a trace to 0.11 oz Au/ton. |
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Indication of production | Yes; small |
Reserve estimates | 500 tons @ 2.27% Cu inferred reserves (Jansons and others, 1984). |
Production notes | 720 lbs. copper from 70 tons of ore shipped in 1905 (Grant, 1906). |
Additional commentsCrowe and others (1992; 1993) and Sainsbury (1993) discuss the genesis of the volcanogenic massive sulfide deposits in this area. Chugach Alaska Corporation, Anchorage, Alaska has control of these lands. |
MRDS Number | 10307358 |
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ReferencesSainsbury, C.L., 1993, Geology and geochemistry of volcanogenic massive sulfide deposits and related igneous rocks, Prince William Sound, south-central Alaska, A discussion: Economic Geology, v. 88, p. 1284-1285.
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Reporters | S.W. Nelson, Anchorage, AK |
Last report date | 6/10/2000 |