The Gran 15 South area is underlain by the contact of a Middle to Late Triassic quartz dioritic pluton and Devonian to Permian sedimentary rock of the Stikine Assemblage.

The main rock type encountered in 1989 was a medium-grained granodiorite, locally migmatitic, with abundant bull white quartz veins up to 30 centimetres in width. These quartz veins were typically barren but where mineralized carried up to 2 per cent blebby chalcopyrite and 5 per cent disseminated pyrite, with 2 to 3 per cent patchy epidote. The Gran 15 South showing is located near Nightout Mountain peak where one such quartz vein was sampled, giving the highest assays of that year. The sample was taken from sheared granodiorite and graded 0.32 per cent copper, 1.3 grams per tonne silver and 13 parts per billion gold (sample 31446, Assessment Report 19059).

WORK HISTORY

In 1973, a program of geologic mapping and rock sampling was carried out on the B and BM claims owned by Bart Mines Ltd. (Assessment Report 4717), which overlap part of the Gran 15 claim. Several mineralized zones were discovered.

In 1989, the Gran 15 property consisted of one claim totalling 20 units and was owned by Homestake Mineral Development Company and Equity Silver Mines Ltd. Work on the property involved prospecting and the collection of 11 rock samples. Work by Homestake included prospecting and the collection of 11 rock samples on the Gran 15 claim which overlapped part of the lapsed B and BM of 1973. Homestake reported that they did not visit the mineralized occurrence found in 1973.

In 1990, exploration by Equity Silver Mines Limited on the Gran 15, Dayin 1 and Canyon 53 involved geological mapping, collection of 7 rock samples and the collection of a bulk heavy mineral sediment sample from the main drainage of the property. No mineralization of note was reported.