Upper Triassic volcanics of the Karmutsen Formation (Vancouver Group), are underlain by altered tuffs of the Paleozoic Sicker Group. The unconformable contact parallels a north-northwest trending band of recrystallized limestone of the Upper Pennsylvanian to Lower Permian Buttle Lake Group.

The May occurrence comprises quartz veining at or near the contact of limestone with altered tuffs of the Sicker Group. Mineralization consists of small amounts of sphalerite, galena, chalcopyrite, pyrite and magnetite. A rock sample assayed greater than 0.99 per cent zinc, 0.18 per cent lead, 0.09 per cent copper and 5.4 grams per tonne silver (Assessment Report 16013).