The region in which the Tezzeron Lake showing occurs is underlain mainly by mafic volcanic rocks and associated sediments of the Upper Triassic Takla Group. The Takla Group rocks are in fault contact, to the west, with the Mississippian to Triassic Cache Creek Group.

The area of the showing is underlain by steeply-dipping, thinly-bedded quartzite and slate, overlain by dark green fine-grained basalt. Mineralization comprises pyrite and arsenopyrite along fractures in a 0.6 metre wide quartz vein in basalt. This vein is exposed for about six metres and extends into Tezzeron Lake. Small amounts of galena and sphalerite occur with the iron sulphides. An assay indicated only trace amounts of gold and silver.