Quadrangle map, 1:250,000-scale | CA |
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Quadrangle map, 1:63,360-scale | C-5 |
Latitude | 65.55 |
Longitude | -161.08 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | The Bear Creek placer mine is along about a mile of Bear Creek between Polar and Bob Creek. The coordinates are for the camp at the junction of Split Creek, on the boundary of sections 23 and 24, T. 2 N., R. 12 W., of the Kateel River Meridian. Cobb, 1972 (MF-389), locations 29 and 30. Also see Additional comments. |
Geologic descriptionBedrock in the mine area is predominately altered, Jurassic andesitic tuff and greenstone which are cut by mafic and felsic dikes. Quartz and calcite veins carry disseminated sulfides. Breccia zones in greenstones also carry disseminated sulfides and have a thin, oxidized cap which carries some gold. Abundant heavy, red, cherty rock in the placer concentrate occurs as crosscutting veins and irregular masses in greenstone. At the Bear Creek gold placer flaky gold and platinum occur on bedrock or in cracks in upper several inches of bedrock. During mining bedrock must be thoroughly cleaned since much of the gold is close to or in cracks in bedrock. The bedrock surface is very irregular. Concentrates contained gold, platinum, magnetite, hematite, pyrite, garnet and chrome spinel (Harrington, 1919). The gold was flaky and worth $19.20 per ounce in 1905. Analysis of platinum minerals from placer concentrate gave the following results: 72.82% Pt; 15.58% Ir, 8.17% Os, 2.29% Ru, 0.78% Rh, and 0.36% Pd (Moffit, 1905). | |
Geologic map unit | (-161.082656756044, 65.5493315272769) |
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Mineral deposit model | Placer Au-PGE (Cox and Singer, 1986; model 39a). |
Mineral deposit model number | 39a |
Age of mineralization | Quaternary. |
Workings or exploration | Small-scale placer mining has been done on Bear Creek since the early 1900s, continuing intermittently until at least the 1960s. Most of the mining has been above and below Split Creek (Herreid, 1965). |
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Indication of production | Yes; small |
Additional commentsSome of the names associated with early mining claims are: Douglass and Edwards, Douglass and Milligrock, Hoxie, Tendness and Barr, Porter, and Wright. Prospecting work was done near the airstrip in 1964 (Herreid, 1965). |
MRDS Number | A015716; M045826 |
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ReferencesMartin, G.C., 1919, Alaska Mining Industry in 1917: U.S. Geological Survey Bulletin 692-A, p. 11-42.
Smith, S.S., 1917, The mining industry in the Territory of Alaska during the calendar year 1915: U.S. Bureau of Mines Bulletin 142, 65 p.
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Reporters | Anita Williams (Anchorage, AK) |
Last report date | 1/12/2000 |