Geologic description
By 1916, the Marion prospect had been explored by a 400-foot adit with a 50-foot winze about 190 feet from the portal (Chapin, 1916). Roehm (1939 [PE 119-18] ) called it the Jack Wilcox prospect, and it was restaked in 1944 (Twenhofel and others, 1949). Wolff and Heiner (1971) indicate that the property has produced about 50 ounces of gold, 3 ounces of silver, and 36 pounds of lead. The rocks in the vicinity are greenschist of the Wales Group of Late Proterozoic and Cambrian age. The adit follows a calcite-bearing quartz vein up to 6 feet thick that is along a shear zone that strikes N20-30W and dips 80W (Herreid and others, 1978). The vein contains small amounts of arsenopyrite, chalcopyrite, galena, pyrite, and sphalerite. Roehm (1939 [PE 119-18]) collected 21 samples across the mineralized zone that averaged 0.06 ounce of gold per ton, and 0.66 ounce of silver per ton; the highest value was 0.66 ounce of gold per ton. As described by Roehm, the mineralized zone is 3 to 12 feet wide and extends for 3,000 feet to an elevation of about 1,000 feet. Maas and others (1991) could not locate the workings under a landslide and recent logging. However, they identified several thin, mineralized fault zones on the surface nearby. A sample from a 4-inch quartz vein in the footwall of a 11-foot-wide fault zone contained 3,828 parts per million (ppm) gold, 12.6 ppm silver, and 5,590 ppm zinc. |