The historic King William camp is located on Mineral Hill within a north trending belt of Upper Triassic intermediate volcanics, volcaniclastics and sediments belonging to the Nicola Group. These greenstones consist of massive, chlorite-epidote altered andesite and basalt, augite porphyry, andesitic flow breccia and tuff, minor interbedded argillite, conglomerate and limestone. Attitudes of tuff horizons and sedimentary bedding suggest that a north plunging axis of a syncline passes through Mineral Hill. Both west and northeast of Stump Lake, the Nicola Group volcanics are intruded by Lower Jurassic granitic batholiths; scattered granodiorite outcrops have been mapped in the vicinity of the camp. Secondary to the north- northeast trending Quilchena and Stump Lake regional faults are numerous smaller faults which form a complex fracture pattern and appear to control alteration and mineralization. Andesitic rocks are bleached, pervasively silicified, pyritic and brecciated. Mineralization occurs in numerous quartz, and less commonly calcite veins which strike generally to the north and dip steeply eastward.

The Marion C showing appears to be the southernmost extension of the King William vein system (092ISE110). The quartz vein, as exposed in old open cuts, is 10 centimetres wide, carries minor pyrite, galena, sphalerite and chalcopyrite and is hosted in altered andesite. A chert unit occurs with beds striking approximately 010 degrees and dipping 50 degrees west. Grab samples from vein material assayed 17.82 grams per tonne silver, 0.09 per cent lead, 0.03 per cent zinc, 0.01 per cent copper and 0.1 grams per tonne gold (Assessment Report 5152).