Half Dollar Creek; Two-Bit Gulch Mine, Circle Mining District, Yukon-Koyukuk Census Area, Alaska, USAi

Regional Level Types
Half Dollar Creek; Two-Bit Gulch Mine	Mine
Circle Mining District	Mining District
Yukon-Koyukuk Census Area	Census Area
Alaska	State
USA	Country

See also Bottom Dollar Creek, ARDF no. CI007.
Location: The location is the approximate center of placered area about 0.5 miles long by 1,000 ft wide on Half Dollar Creek below the mouth of Two-Bit Gulch. Some mining was on Two-Bit.
Geology: The entire length of both Two-bit Creek and Half Dollar Creek is underlain by a Cretaceous pluton described by Wiltse and others (1995) as chloritized porphyritic (hornblende) biotite monzogranite. Primary trace minerals in the granite include zircon, allanite, apatite and ilmenite. Uranium has been detected by fluorimetric tests (Eberlein and others, 1977). Minerals in the heavy-mineral fraction of concentrates from the granite contain allanite, hematite, limonite, pyrrhotite, scheelite, sphene and zircon. Stream placer concentrates contain gold, scheelite and cassiterite. The paystreak is narrow and the gold distribution is spotty (Cobb, 1976, [OFR 76-633]). The unmined gravel on Half Dollar Creek is mostly colluvium derived from side slopes (Yeend, 1991). Prospecting and/or mining occurred in 1909 to 1914, 1935, 1938 to 1942, and probably 1976 to 1980 (Menzie and others, 1983). Several small placers were operated along this drainage in the early 1980's (Yeend, 1991). Production from these operations is unknown.
Workings: Prospecting and/or mining occurred in 1909 to 1914, 1935, 1938 to 1942, and probably 1976 to 1980 (Menzie and others, 1983). Several small placers were operated along this drainage in the early 1980's (Yeend, 1991).
Production: Prospecting and/or mining occurred in 1909 to 1914, 1935, 1938 to 1942, and probably 1976 to 1980 (Menzie and others, 1983). Several small placers were operated along this drainage in the early 1980's (Yeend, 1991). Amount of gold produced from these operations is unknown.

Commodities (Major) - Au; (Minor) - Sn, W
Development Status: Yes; small
Deposit Model: Placer gold deposit (Cox and Singer, 1986; model 39a)

Other Databases

Link to USGS - Alaska:	CI024

Other Regions, Features and Areas containing this locality

References