The McQuillan showing is located just southwest of McKinlay Peak, about 16 kilometres southeast of Port Alberni.

The area is underlain by volcanics of the Paleozoic Sicker Group. These are a complex, interlayered succession of basaltic pillowed flows, basaltic volcaniclastics, hematitic jasper and dacitic agglomerate lapilli tuff. The succession is upright, strikes northwest to north and dips 20 to 40 degrees southwest.

Pillowed amygdaloidal basalt of the Devonian Duck Lake Formation (Sicker Group), contains one or two pyritic alteration fracture zones up to 3 centimetres wide with disseminated pyrite and fracture-filled chalcopyrite. A grab sample assayed 0.184 per cent copper, 0.01 per cent zinc and 1.8 grams per tonne silver (Assessment Report 13904).