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The historic Enterprise camp is located on Mineral Hill, approximately 5.5 kilometres southwest of the community of Stump Lake. The Joshua occurrence is located 500 metres east-northeast 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. In addition to the regional Quilchena and Stump Lake faults, which trend north-northeast, numerous smaller subsidiary faults create a complex fracture network that appears to control both alteration and mineralization. The andesitic host rocks are intensely altered, exhibiting pervasive bleaching, silicification, pyritization, and brecciation. Mineralization is hosted primarily within numerous quartz veins and, less commonly, calcite veins. The Joshua vein follows a shear zone striking 356 degrees and dipping 60–65 degrees east; however, its orientation varies locally due to intense fracturing. Vein widths range from 5 to 75 cm and are accompanied by numerous smaller veins and stringers that branch outward from the main structure. 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. The Joshua mine originally consisted of a 230 metre deep shaft with workings on six levels. 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).
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