Crooked Creek

Mine, Inactive

Commodities and mineralogy

Main commodities Ag; Au
Other commodities Hg
Ore minerals arsenopyrite; cassiterite; cinnabar; placer gold
Gangue minerals ilmenite; magnetite

Geographic location

Quadrangle map, 1:250,000-scale SM
Quadrangle map, 1:63,360-scale D-7
Latitude 61.99536
Longitude -158.25789
Nearby scientific data Find additional scientific data near this location
Location and accuracy About 0.8 miles of Crooked Creek above the mouth of Crevice Creek have been mined in the Sleetmute quadrangle. The placer extends upstream for another 6 miles into the Iditarod quadrangle. The placer in the Sleetmute quadrangle extends through the east half of section 16, T. 22 N., R. 49 W. The coordinates are the center of the placer in the Sleetmute quadrangle. The mine is locality 1 of Miller and others (1989). The location is accurate.

Geologic setting

Geologic description

The Crooked Creek placer deposit is a southern extension of the gold placer deposits in Donlin Creek in the Iditarod quadrangle (ARDF ID176; Bundtzen Miller, and Hawley, 2004) About 1 mile of the placer is in the Sleetmute quadrangle; the rest is in the Iditarod quadrangle.
The Crooked Creek placer above the mouth of Crevice Creek in the Sleetmute quadrangle consists of an ancestral alluvial terrace deposit that is a southerly extension of the 'Donlin Bench' (Cady and others, 1955). This gold-bearing bench is approximately 20 feet above the present stream level; it is up to 1 mile long and there is 10 to 100 feet of gravel over bedrock. Gold was mainly concentrated where gulches flow into Crooked Creek; thus mining was mainly in zones about 300 to 600 feet long and 300 to 450 feet wide at the mouth of Crevice Creek and just below Anaconda Creek. The principal heavy minerals recovered during placer mining are gold, cinnabar, arsenopyrite, and a trace of cassiterite. According to Bundtzen and others (1987), at least 4,200 ounces of gold and 120 ounces of silver were recovered from Crooked Creek in both the Sleetmute and Iditarod quadrangles from 1911 to 1956. However, the amount mined in the Sleetmute quadrangle alone is not known.
Geologic map unit (-158.260297513998, 61.9946643046667)
Mineral deposit model Placer Au (Cox and Singer, 1986; model 39a).
Mineral deposit model number 39a
Age of mineralization Tertiary or early Quaternary; based on similarities with other dated placers in interior Alaska (Hopkins and others, 1971; Hamilton, 1994).
Alteration of deposit None.

Production and reserves

Workings or exploration Placer deposits were discovered on Crooked Creek in 1910 and production began in 1911 (Cady and others, 1955; Cobb, 1972, [MF 368]). Exploration and development cuts were first made by horse and scraper and then by diesel-driven machinery (Maddren, 1911 and 1915; Brooks, 1912; Mertie, 1936; Cady and others, 1955).
Indication of production Yes
Production notes Old, heavily vegetated, filled pits and bulldozer cuts that were observed in 1984 (T.K. Bundtzen, unpublished field data) indicate that the last placer mining in Crooked Creek took place many years previously. According to Bundtzen and others (1987), at least 4,200 ounces of gold and 120 ounces of silver were recovered from Crooked Creek in both the Sleetmute and Iditarod quadrangles from 1911 to 1956. However, the amount mined in the Sleetmute quadrangle alone is not known.

References

MRDS Number A013426

References

Bundtzen, T.K., Cox, B.C., and Veach, N.C., 1987, Heavy mineral provenance studies in the Iditarod and Innoko districts, western Alaska: Process Mineralogy VII, The Metallurgical Society, p. 221-246.
Hamilton, T.D., 1994, Late Cenozoic glaciation of Alaska, in, Plafker, G., and Berg, H.C., eds., The Geology of Alaska: Boulder, Colorado, Geological Society of America, The Geology of North America, v. G-1, p. 813-844.
Hopkins, D.M., Matthews, J.V., Wolfe, J.A., and Silberman, M.L., 1971, A Pliocene flora and insect fauna from the Bering Sea region: Paleoecology, vol. 9, p. 211-231.
Reporters T.K. Bundtzen (Pacific Rim Geological Consulting, Inc.) and M.L. Miller (U.S. Geological Survey)
Last report date 5/3/2003