A moderately eastward dipping and highly folded sequence of gneisses of the Shuswap Metamorphic Complex which mantles the Frenchman Cap Dome. The dominant rock type is a massive, white, muscovite and tourmaline-bearing quartzite which is overlain by an impure calc-silicate gneiss. Biotite rich gneisses lie above and below the quartzite. Other rocks include intermediate to basic sills, and pegmatites and aplites.

The rocks lie several hundred metres beneath the gently east dipping Columbia River Fault zone. Mylonite and mylonitic gneiss splay from the fault zone.

Minor sulphides consisting of pyrite, chalcopyrite and pyrrho- tite lie within the mylonitic foliation and in steeply dipping, undeformed late fractures which cut the foliation. The mylonitic zones are chloritized, epidotized and carbonated, yielding a pro- pylitic alteration assemblage which contrasts sharply with and overprints the high grade sillimanite zone regional metamorphism of the unaltered rocks (Assessment Report 14270).

Drill hole E-5 intersected a protoclastic biotite-muscovite- quartz-feldspar gneiss with silver values averaging 13.4 grams per tonne silver over 1 metre (Assessment Report 14270).