The historic Jenny Long camp is located south of 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 Moon showing consists of several old trenches in andesite which expose quartz-carbonate stringers up to 7.5 centimetres wide in a zone striking 355 degrees and dipping 55 degrees southwest. The vein contains considerable scheelite, sparse galena, sphalerite, chalcopyrite and pyrite.