The Osi occurrence is located along or near a ridge crest about 1.7 kilometres north of the summit of Razorback Mountain, 128 kilometres northwest of the community of Mackenzie.

At the showing, a small occurrence of galena was located in a fault plane cutting limestone near a contact with phyllite. Both rock types are part of the Lower Cambrian Mount Kison Limestone (Atan Group) which underlies the area.

In 1974, Serem Ltd. carried out detailed geological mapping and rock (168 chip) and soil (867) geochemical sampling on the Osi group of claims. Rock chip sample (27) assayed 1170 parts per million (ppm) lead, 3200 ppm zinc and 3.1 ppm silver (Assessment Report 5454).