The historic Enterprise camp is located on Mineral Hill, approximately 5.5 kilometres south of the community of Stump Lake. The Joshua occurrence is located 500 metres north east of the Enterprise Mine (MINFILE 092ISE028) and a complete exploration history can be found there.
The camp is hosted 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 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 Joshua mine originally consisted of a 230 metre deep shaft with workings on six levels. The Joshua vein follows a shear zone striking 356 degrees and dipping 60 to 65 degrees to the east, though intense fracturing causes changes in orientation. The vein varies in width from 5 to 75 centimetres with numerous smaller veins and stringers feathering out. Mineralization consists of pyrite, galena, sphalerite, chalcopyrite and tetrahedrite in variable amounts. Trenching has exposed similar mineralization within the altered andesitic unit northwest and southeast of the Joshua shaft. Scheelite masses up to 10 centimetres in diameter is found in dump material.
Production from the Enterprise (MINFILE 092ISE028), King William (MINFILE 092ISE110), Tubal Cain and Joshua (MINFILE 092ISE109) veins, from 1916 to 1944, totalled 70,390 tonnes with recovery grades of 3.4 grams per tonne gold, 101.9 grams per tonne silver, 0.026 per cent copper, 1.42 per cent lead and 0.24 per cent zinc (Assessment Report 31405).