Quadrangle map, 1:250,000-scale | CA |
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Quadrangle map, 1:63,360-scale | B-5 |
Latitude | 65.34 |
Longitude | -161.31 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | The lower Sweepstakes Creek placer mine is along Sweepstakes Creek at Bear Gulch, an eastward-flowing, informally named tributary which drains Bear Mountain. The mine is in section 3, T. 2 S., R. 13 W., of the Kateel River Meridian. At various times, the claims at this site also have been referred to as Eagle, Circle, Rampart, and Fairbanks; A. Johnson; Moon; W. Porter; and J. Winder. Cobb, 1972 (MF-389), location 41. |
Geologic descriptionPlacer mining at this site was mainly in low bench deposits along the east side of Sweepstakes Creek. On these benches 2 to 6 feet of muck overlies 3 to 6 feet of gravel. Gravels in the creek bed are 6 to 14 feet deep. On lower claims depth to bedrock is 15 feet. Partially decomposed bedrock was excavated during mining to a depth of a few inches. Mining was mainly for gold, but a little platinum was recovered near the mouth of Bear Gulch. Sweepstakes Creek drains the southwestern part of the Cretaceous Granite Mountain monzonite pluton. Samples of concentrates or syenite-rich stream gravels contained chrome spinel, garnet, hematite, hydrothorianite, ilmenite, magnetite, uranothorianite, and zircon (Gault and others, 1953). | |
Geologic map unit | (-161.312631587862, 65.3393223865032) |
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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 gold placer mining took place at this site from the 1900s until the 1950s. Some activity was reported in the area in 1989-1991 (Bundtzen and others, 1990; Bundtzen and others, 1992). In 1947 the U.S. Geological Survey sampled the placer to evaluate its radioactive mineral potential. |
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Indication of production | Yes; small |
Production notes | Gold worth $10,000 and an ounce of platinum reportedly were mined in 1917 (gold at $20.67/ounce) (Harrington, 1919). On Moon's claims 9 and 10, a placered area of 1,500 square feet consisted of 6 feet of gravel overlain by 6 feet of tundra. The paystreak was in a half-foot of gravel and 1 foot of bedrock. Moon recovered 9 ounces of gold at $28.50 per ounce (Gault and others, 1953). |
Additional commentsStream gradient approximately 50 feet per mile. |
MRDS Number | A015725; M045361 |
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References | |
Reporters | Anita Williams (Anchorage, AK) |
Last report date | 1/12/2000 |