The Maybelle Fraction showing is located within the historic King William camp on Mineral Hill, approximately 6 kilometres southwest of the community of Stump Lake.

The occurrence is hosted within a north-trending belt of Upper Triassic Nicola Group intermediate volcanic, volcaniclastic, and sedimentary rocks. These greenstones comprise massive chlorite-epidote altered andesite and basalt, augite porphyry, andesitic flow breccia and tuff, with minor interbedded argillite, conglomerate, and limestone. The attitudes of tuffaceous horizons and sedimentary bedding indicate that the axis of a north-plunging syncline passes through Mineral Hill. Lower Jurassic granitic batholiths intrude the Nicola Group sequence both west and northeast of Stump Lake, and scattered granodiorite outcrops occur in the vicinity of the camp. In addition to the regional north- to northeast-trending Quilchena and Stump Lake fault systems, numerous subsidiary faults form a complex fracture network that appears to control alteration and mineralization. The andesitic rocks are characteristically bleached, pervasively silicified, pyritic, and brecciated. Mineralization occurs in numerous quartz, and less commonly calcite, veins that generally strike northward and dip steeply to the east.

The Maybelle Fraction showing is interpreted to represent the extension of the Joshua (092ISE109) and Tubal Cain (092ISE108) vein systems. Diamond drilling completed in 1983 intersected mineralized quartz veins and veinlets hosted within strongly altered and brecciated greenstone. The altered wallrock contains up to 5 per cent pyrite, together with minor galena and chalcopyrite, and returned assays of up to 71.99 grams per tonne silver, 1.75 per cent lead, 0.66 per cent zinc, 0.06 per cent copper, and 0.75 grams per tonne gold over 1.2 metres (Assessment Report 13152). Sulphide minerals also occur as blebs within the quartz veins; however, these veins have generally yielded low assay values (Assessment Report 41373).