Eagle Cliff; Eagle Bluff Mine, Koyukuk District, Yukon-Koyukuk Borough, Alaska, USA

Location: The Eagle Cliff placer mine is on the north bank of the South Fork, Koyukuk River, about 12 miles east-southeast of Tramway Bar. The mine is near the west end of Eagle Cliff, a geographic feature shown on the Wiseman A-1 topographic map (1975 ed.) in sections 29 & 30, T. 26N., R. 11W., of the Fairbanks Meridian. The extent of the placer is uncertain but it may extend a mile or so to the east along the valley floor at the base of the Eagle Cliff bluff. The location is accurate to within 1 mile.
Geology: Gold in coarse, wheat-sized rounded grains, was mined from well-washed gravel on top of a bench cut into rock about 10-12 feet above the low-water level of the South Fork Koyukuk River (Maddren, 1913). Reed (1938) noted that Eagle Bluff was said to be a high channel that resembled the Ironside Bench and Gold Bench placers (both in the Bettles quadrangle) about 15-20 miles downstream. A waterwheel was used to raise water to work the placer in 1899 (Schrader, 1900). Four or five men worked the placer in 1910. Reed (1938) noted that no one was working the site in 1937, although there were plans to work there in 1938. Maddren (1913) noted that $1,000 in gold was produced from 1900 to 1909, and an additional $1,500 in gold was produced in 1910.
Workings: A waterwheel was used to raise water to work the placer in 1899 (Schrader, 1900). Four or five men worked the placer in 1910. Reed (1938) noted that no one was working the site in 1937, although there were plans to work there in 1938.
Age: Quaternary.
Production: Maddren (1913) noted that $1,000 in gold was produced from 1900 to 1909, and an additional $1,500 in gold was produced in 1910.

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

References:
Bliss, J.D., Brosg