The Goodnews Bay district (fig. 13) is the area drained by streams flowing to Kuskokwim Bay from (and including) Carter Bay to Cape Newenham.
The first mining in the district was on tributaries of the Good-news River that head in the divide separating the basins of the Goodnews and Arolik Rivers (fig. 14). Claims were staked on Bear Creek (11—12, fig. 14) in 1916, and soon after that richer deposits were found on Wattamuse Creek (8, fig. 14). Mining was reported for nearly every year thereafter on Wattamuse Creek or on Slate Creek (8, fig. 14), into which Wattamuse flows, until 1961. The bedrock source of the gold is probably quartz veins in contact zones around one or more granitic plutons in the divide in which all these streams head.
The most extensive mining in the Goodnews Bay district is on the Salmon River and its tributaries (fig. 15), where platinum was discovered at the mouth of Fox Gulch (12, fig. 15) in 1926. The Clara Creek Mining Co. worked out Clara (10, fig. 15) and Dowry (11, fig. 15) Creeks between 1936 and 1940; and the Goodnews Bay Mining Co., now the sole operator in the area, began mining on Platinum Creek (12, fig. 15) in 1934. Mining has been with mechanized equipment, including a dredge that has worked or will work most of the gravel in the Salmon River valley (12, fig. 15). Total production from the Salmon River and its tributaries from 1934 to 1966 is estimated to have been well over half a million troy ounces of platinum-group metals (a major por¬tion of the United States primary production) and a small amount of gold. Data on production since 1966 are not available, but operations have been on about the same scale as earlier years. The average percentages for platinum-group metals, gold, and impurities based on data from the Goodnews Bay Mining Co. (Mertie, 1969, p. 87) are: platinum, 73.62; iridium, 9.94; osmium, 1.89; ruthenium, 0.15; rhodium, 1.15; palladium, 0.34; gold, 2.06; and impurities, 10.85. The source of the platinum-group metals is the ultramafic body, composed of dunite and serpentinite, that makes up Red Mountain. Although no minable platinum has been found in any part of Red Mountain, a concentrate of residual ma¬terial from near the top of the mountain (9, fig. 15) contained platinum, as did material in a small amphitheater (2, fig. 15) west of the divide at the head of Platinum Creek. Chromite, which is a component of concentrates from the Salmon River and some of its tributaries, is a constituent of the ultramafic body. The gold in the placers was derived from glacial deposits that came from the east.