By A. H. KOSCHMANN and M. H. BERGENDAHL - USGS 1968
Click here for the Principle Gold Producing Districts of the United States Index
Gold is the principal mineral resource of Humboldt County. The bulk of the production has been from Quaternary placer deposits in channels and terraces along the Trinity and Klamath Rivers. There has also been some placer mining of beach sands. Averill (1941b, p. 508-516) listed six lode properties and 12 placer properties in the county. Total production through 1959 was 131,300 ounces of gold.
There are some lode deposits in quartz veins in andesite, in Precambrian schists, and in diorite, but details of the geology of the county have not been published.
