Utopia Creek

Mine, Probably inactive

Commodities and mineralogy

Main commodities Au
Ore minerals galena; gold; sphalerite; tetrahedrite

Geographic location

Quadrangle map, 1:250,000-scale MZ
Quadrangle map, 1:63,360-scale D-2
Latitude 65.9822
Longitude -153.7379
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Utopia Creek placer mine follows the channel of Utopia Creek for about 3 miles upstream from its junction with the Indian River. The coordinates are at about the midpoint of the mined portion of the creek, which is shown on the 1:63,360-scale topographic map. The mined area is centered about 0.6 mile northeast of the center of section 26, T. 7 N., R. 24 E. and R. 25 E. The location is accurate.

Geologic setting

Geologic description

The rocks in the Utopia Creek area consist of Cretaceous andesite and basalt interlayered with chert, cherty tuff, conglomerate, and coquinoidal limestone (Patton and others, 1977). The Indian Mountain granodiorite pluton crops out approximately 2 miles northwest of the placer workings, and podlike intrusions of fine-grained, pyritiferous, silicified, felsic rock occur along an east-northeast-trending fault about 1.5 miles south of the workings. The gradient of upper Utopia Creek is about 200 feet per mile; the gradient at the mouth is about 75 feet per mile. Unlike other gold-bearing streams in the area, Utopia Creek does not drain the Indian Mountain granodiorite intrusion (Miller and Ferrians, 1968).
Bedrock in Utopia Creek is slightly metamorphosed andesite cut by fine-grained felsic rock (Miller and Ferrians, 1968). Boulders of massive barite are in the tailings of an abandoned placer mine near the head of Utopia Creek, and some of those boulders contain tetrahedrite, sphalerite, and galena (Miller and Ferrians, 1968). That mineralization is described in record ARDF MZ005.
Gold was discovered in Utopia Creek in about 1906 (Cobb, 1975) and mining was reported as early as 1915. J.Q. Hackett, R.B. Norris, and C.B. Frank prospected and did a little mining on Utopia Creek in 1929 (Wimmler, 1929). L. McGee and a crew of 12 men began prospecting on Utopia Creek in 1936 (Smith, 1938). Overburden was stripped and a bedrock drain dug in 1937 by about a 20-man crew employed by McGee (Smith, 1939 [B 910A]). Large-scale mining was started in 1938 (Smith, 1939 [B 917-A]). McGee ran the operation and for several years employed approximately 30 men. At the time, Utopia Creek was the largest placer operation in the district (Smith, 1941). In 1939, McGee divided the property into two segments. The upstream section was mined by hydraulic methods when water was available. The pay streak in that portion of the creek was on the south side of the drainage. Heavy machinery and draglines were used on the downstream portion, where gravels were as much as 25 feet thick (Smith, 1941). Large-scale mining continued until 1952 (Cobb, 1973). U.S. Geological Survey topographic maps of the Melozitna quadrangle show workings along approximately 3.5 miles of Utopia Creek; the upper tailings continuing along a draw on the south side of the creek. The remains of a 40-foot long washing plant lie in a heavily vegetated area along the lower creek (Kurtak and others, 2002). The configuration of the tailings piles indicates that mining concentrated on deposits in the modern stream channel. The average grade of the placer, which started at 0.032 ounce of gold per cubic yard, was down to 0.003 ounce per cubic yard by the last year of production (Kurtak and others, 2002). The fineness of a placer gold sample from Utopia Creek was 849 (Metz and Hawkins, 1981).
At least 8,850 ounces of gold were mined on Utopia Creek (Cobb and Miller, 1981).
Geologic map unit (-153.740522643432, 65.9816610926914)
Mineral deposit model Placer Au (Cox and Singer, 1986; model 39a).
Mineral deposit model number 39a
Age of mineralization Quaternary.

Production and reserves

Workings or exploration Gold was discovered in Utopia Creek around 1906 (Cobb, 1975; Eberlein and others, 1977) and mining was reported as early as 1915. J.Q. Hackett, R.B. Norris, and C.B. Frank prospected and did a little mining on Utopia Creek in 1929 (Wimmler, 1929). L. McGee and a crew of 12 men began prospecting on Utopia Creek in 1936 (Smith, 1938). Overburden was stripped and a bedrock drain dug in 1937 by about a 20-man crew employed by McGee (Smith, 1939 [B 910A]). Large-scale mining was started in 1938 (Smith, 1939 [B 917-A]). McGee ran the operation and for several years employed approximately 30 men. At the time, Utopia Creek was the largest placer operation in the district (Smith, 1941). In 1939, McGee divided the property into two segments. The upstream section was mined by hydraulic methods when water was available. The paystreak in that portion of the creek was on the south side of the drainage. Heavy machinery and draglines were used on the downstream portion, where gravels were as much as 25 feet thick (Smith, 1941). Large-scale mining continued until 1952, when interest apparently waned (Cobb, 1973). U.S. Geological Survey topographic maps of the Melozitna quadrangle show workings along approximately 3.5 miles of Utopia Creek, with the upper tailings continuing along a draw on the south side of the creek. The remains of a 40-foot long placer wash plant lie in a heavily vegetated area along the lower creek (Kurtak and others, 2002). The configuration of the tailings piles indicates that mining concentrated on deposits in the modern stream channel.
Indication of production Yes; medium
Production notes Utopia Creek was probably the largest gold producer in the Koyukuk district (Smith, 1941) but there is no detailed record of production. Cobb and Miller (1981) estimate that about 8,850 ounces of gold were mined on Utopia Creek but it may have been more than 10,000 ounces. Kurtak and others (2002) reported that 8,854 ounces of gold were recovered from 1939 to 1950, but the records are incomplete and there was substantial production before 1939.

Additional comments

This site is the Utopia Creek, U.S. BLM MILS location 0020470011.

References

MRDS Number A010759; A015573

References

Kurtak, J.M., Klieforth, R.F., Clark, J.M., and Maclean, E.A., 2002, Mineral investigations in the Koyukuk mining district, northern Alaska: Final Report: U.S. Bureau of Land Management Technical Report 50, v. 1 and 2, 845 p.
Metz, P.A., and Hawkins, D.B., 1981, A summary of gold fineness values from Alaska placer deposits: University of Alaska, Fairbanks, Mineral Industry Research Laboratory Report No. 45, 56 p.
Reporters G.E. Graham, D.J. Szumigala (ADGGS); D.J. Grybeck (Contractor, USGS)
Last report date 2/1/2011