The Doss showing occurs in a region underlain dominantly by plutonic rocks of the Jurassic to Tertiary Coast Plutonic Complex. Preserved locally within these plutonic rocks are roof pendants of metasedimentary rocks, probably of Paleozoic age.

The Doss showing consists of quartz veins occupying faults and fracture zones within quartz diorite adjacent to phyllite, biotite-feldspar schist, marble and hornfels. Intruding both the metasediments and the quartz diorite are quartz-feldspar porphyry dykes. Mineralization consists of pyrite, stibnite and arsenopyrite along with malachite and limonite in quartz veins which fill fractures and along gouge-filled fault zones.

Wallrock alteration to the mineralized quartz veins is generally not well developed except immediately adjacent to the veins where rocks are silicified and, in places, contain disseminated pyrite. Clay alteration associated with fault zones occurs in some areas.

A rock sample taken in 1983 assayed 0.75 gram per tonne gold (Assessment Report 11144, Map No. 4).