The region is underlain by (?)Hadrynian to Paleozoic Snowshoe Group rocks. The Snowshoe Group is an assemblage of dominantly metasedimentary rocks within the Barkerville Terrane of south-central British Columbia. The metasedimentary rocks consist primarily of marble, quartzite and phyllite which in the area of the Gisco showing comprise the Downey succession (informal). Metamorphism of the region varies from chlorite to sillimanite and higher grade. The lode gold deposits of the region occur in rocks metamorphosed no higher than greenschist facies.

A fracture-filling quartz vein, hosted by quartzite, is exposed for a maximum width of about 30 centimetres. The quartzite strikes northwest and the quartz vein strikes 080 degrees, dipping 70 degrees north. Pyrite, galena and rare specks of visible gold occur within the quartz vein. In 1946, a grab sample of the Gisco vein assayed 10.96 grams per tonne gold (Minister of Mines Annual Report 1946, page A94).

In 1983, a program of silt, soil, heavy mineral and rock sampling and geological mapping was conducted on the Pitt claims on behalf of Pluton Resources Ltd. In 1996, geological mapping was conducted in a 3 square kilometre area on the western portion of the Nugget Mountain property; a total of 129 soil samples and 49 rock samples were collected. The Gisco showing is located within a 1 kilometre radius of several showings (Pitt 1 (093A 053), Pittman (093A 057)) that were explored along Antler Creek in the 1930s and 1940s, near the mouths of Nugget Gulch and Victorian Creek. In 1987, Rise Resources Inc. completed 419 kilometres of helicopter-borne magnetic and VLF-EM survey over their block of claims which covered the Zone showing. In 2005, a total of 43 samples (9 soil, 1 moss mat silt and 33 rock) were taken on the Nugget Mountain project claims, which covers the showing, on behalf of claim owners R.J. Menard and G.J. Newell.