Rocks in the area are probable Upper Proterozoic Horsethief Creek Group consisting of crystalline limestone overlain by quartzite and underlain by metamorphosed black argillite. The rocks are iso- clinally folded and dip about 50 degrees to the southwest.

The original discovery is in quartzite and quartz-mica schist in the apex of a sharp fold surrounded by crystalline limestone estimated to be 30 metres or more thick. Quartz masses roughly follow the bedding but also break across it in the fractured apex of the fold in quartzite. A length of about 12 metres of quartz lenses in quartzite is exposed on the northwesterly limb of the fold, in masses up to 1.8 metres wide. Coarsely cubic galena occurs in masses as much as 0.6 metre across.

Limestone replacement by sphalerite and galena, in 8 to 10 centimetre bands, occurs in the northwesterly limb of the same fold (Annual Report, 1951).