A copper-bearing lode, reported to contain as much as 2 ounces of gold per ton (Smith, 1908), occurs above Osborn Creek (NM278), but much of the placer gold is probably reworked from coastal plain deposits.? Small-scale mining began about 1903 (Collier and others, 1908, p. Gold was mostly coarse and well rounded, although some pieces were angular. Gravels were about 5 to 6 feet thick above a false bedrock in a pay section 100 feet wide. Gravels probably contained about 2.50 to 4.50 dollars in gold (gold at 20.67 dollars per ounce Collier and others, 1908, p. 171).? Shallow placer deposits were mined for about 5 miles above the mouth of the Osborn Creek. Granite boulders believed by Collier to come from the Kigluaik Mountains were found as high as 800 feet on the 1,000-foot-tall mountain south of Willow Creek (Collier and others, 1908, p.
Boulders of greenstone and granite (orthogneiss?) are abundant. Gravel was composed mostly of schist, marble, and quartz. Michaels Creek (NM277), Osborn Creek placer deposits mostly have gravel walls and paystreaks are floored by clay-rich false bedrock. Geologic Description = Placer gold was discovered on Osborn Creek in 1900.
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