Geologic description
The Mineral Queen prospect was discovered before 1887 and was developed by a 410-foot adit, a 40-foot adit, a 18-foot adit, an open cut and several trenches. The deposit is in phyllite, chlorite schist and coarse- to fine-grained amphibolite that contains disseminated pyrite, pyrrhotite, and chalcopyrite (Redman and others, 1989). Shearing has converted some of the amphibolite to chlorite phyllite that contains quartz veins up to 6 feet thick. Some of the veins contain fragments of altered albite-diorite. Pyrite cubes and molybdenite occur in the margins of the veins and along the foliation of the chlorite phyllite. U.S. Bureau of Mines samples contained up to 441 ppm gold, 34 ppm silver, 1,184 ppm copper, and 0.13 percent molybdenum (Redman and others, 1989). The rocks in the general area are Upper Jurassic or Cretaceous marine argillite and graywacke, interbedded with andesite or basalt (Brew and Ford, 1985). The bedded rocks are regionally metamorphosed to prehnite-pumpellyite or greenschist grade, and cut by diorite or gabbro dikes and sills. |