The Terry property is located at the western contact of the Late Triassic-Early Jurassic Guichon Creek batholith with the Carboniferous to Jurassic Cache Creek Complex. Guichon rocks comprise diorite and quartz diorite. Cache Creek rocks comprise greywacke, chert and limestone that dip mainly eastward.

Disseminated magnetite, pyrite, chalcopyrite and malachite occur in gossans in altered Cache Creek sediments. Concentration of sulphides increases with brecciation and shearing. Two main gossans occur, the Coldstream zone (092INW048) and the Pukaist zone. The Pukaist zone is located about 1524 metres north of Pukaist Creek. The zone is about 1500 metres long and 45 metres wide. Early work consisted of hand trenches and a 30-metre adit driven to intersect a shear containing malachite and chalcopyrite; the adit did not intersect the shear. The shear is about 15 metres wide and 38 metres west of the adit.

In 1969, Largo Mines Ltd. completed geological mapping on the Coldstream and Pukaist zones. In 1971, Largo Mines Ltd. conducted VLF-EM and magnetic surveys on both zones.