|Quadrangle map, 1:250,000-scale||SR|
|Quadrangle map, 1:63,360-scale||C-7|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The placer mine is located near the east bounary of section 6 in T. 7 N., R. 1 E., of the Seward Meridian. The mine is about a mile upstream from the junction of Silvertip Creek with East Fork Sixmile Creek. This is location 146 of Cobb and Richter (1972), location169 of MacKevett and Holloway (1977), location 19 of Tysdal (1978 [MF-880-B]), location 146 of Cobb and Tysdal (1980), and location P-75 of Jansons and others (1984). This location is accurate to within 300 feet.|
The upper portion of Silvertip Creek occupies a steep, narrow, bedrock canyon partially filled with avalanche debris. The lower sections occupy a slightly wider channel, where bedrock near the surface is covered by poorly washed and stratified clay-rich gravels containing gold. The lowermost section flows over an alluvial fan consisting of moderately well stratified and washed gravels. Bedrock of the area is the Valdez Group of Late Cretaceous age (Nelson and others, 1985).Silvertip gold has been reported to be similar to Gulch Creek gold (see SR029), but the nuggets were not so large. Most of the larger nuggets had quartz attached (Johnson, 1912). Scheelite has been found in the concentrate (Jasper, 1967).
|Geologic map unit||(-149.361553065075, 60.728535332612)|
|Mineral deposit model||Placer Au (alluvial) (Cox and Singer, 1986; model 39a).|
|Mineral deposit model number||39a|
|Age of mineralization||Quaternary.|
|Workings or exploration||
Pick and shovel operations occurred between 1897 and 1904. In 1911, a small hydraulic operation was attempted about a mile above the point where Silvertip Creek joins East Fork Sixmile Creek (Moffit, 1906). This operation worked the shallow creek gravels, 3 to 4 feet deep, for about six weeks before the work was abandoned (Johnson, 1912). The gold was reported to be similar to that at Gulch Creek (see SR029), but the nuggets were not so large. Most of the larger nuggets had quartz attached (Johnson, 1912).
Small mechanized operations have mined sporadically since 1950 and suction dredges since 1975 (Jansons and others, 1984).The U.S. Bureau of Mines collected one sample, which yielded .0019 ounce of gold per cubic yard (Jansons and others, 1984).
|Indication of production||Yes; small|
|Reserve estimates||The inferred placer gold reserve base is estimated at greater than 1,000,000 cubic yards (Jansons and others, 1984).|
|Production notes||The U.S. Bureau of Mines estimated the production at 750 to 1,000 ounces, of which 50 to 100 ounces are estimated to have been recovered since 1975 (Jansons and others, 1984).|
Cobb, E.H., and Richter, D.H., 1972, Metallic mineral resources map of the Seward quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-466, 2 sheets, scale 1:250,000.
Cobb, E.H., and Tysdal, R.G., 1980, Summaries of data on and list of references to metallic and selected nonmetallic mineral deposits in the Blying Sound and Seward quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-621, 276 p.
Hoekzema, R.P., and Sherman, G.E., 1983, Mineral investigations in the Chugach National Forest, Alaska (Peninsula study area): U.S. Bureau of Mines in-house report; held at U.S. Bureau of Land Management Alaska State Office, Anchorage, 524 p.
Jansons, Uldis, Hoekzema, R.B., Kurtak, J.M., and Fechner, S.A., 1984, Mineral occurrences in the Chugach National Forest, southcentral Alaska: U.S. Bureau of Mines Mineral Land Assessment 5-84, 218 p., 2 sheets, scale 1:250,000.
Johnson, B.L., 1912, Mineral resources of Alaska, report on progress of investigations in 1911--Gold deposits of the Seward-Sunrise region, Kenai Peninsula: U.S. Geological Survey Bulletin 520-E, p. 131-173.
MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous and selected non-metalliferous mineral deposits in the eastern part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-A, 99 p., 1 sheet, scale 1:1,000,000.
Martin, G.C., Johnson, B.L., and Grant, U.S., 1915, Geology and mineral resources of Kenai Peninsula, Alaska: U.S. Geological Survey Bulletin 587, 243 p.
Moffit, F.H., 1906, Gold fields of the Turnagain Arm region: U.S. Geological Survey Bulletin 277, p. 7-52.
Nelson, S.W., Dumoulin, J. A., and Miller, M.L., 1985, Geologic map of the Chugach National Forest, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1645-B, 16 p., 1 sheet, scale 1:250,000.
|Reporters||Jeff A. Huber (Anchorage)|
|Last report date||4/30/2000|