The historic Enterprise 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, and 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 north- east 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. Mineral- ization occurs in numerous quartz, and less commonly calcite veins which strike generally to the north and dip steeply eastward.
The Enterprise mine consists of a 98 metre deep shaft, a 232 metre adit and approximately 1950 metres of underground development on six levels. The 97 metre level was extended over 400 metres to the northwest to intersect the Tubal Cain (092ISE108) and Joshua (092ISE109) veins. The Enterprise workings developed both the Enterprise and King William (092ISE110) veins. The orientation of the Enterprise vein varies from 335 to 015 degrees, with an average dip of 50 degrees eastward. Its width is generally less than 60 centimetres, but swells up to 2 metres. Mineralization consists of galena, sphalerite and pyrite, with associated gold and silver values.