The San Juan Ridge occurrence is located in the head waters of Three Arms Creek, near the western boundary of the San Juan Ridge Ecological Reserve.

The area is underlain by greenstone, argillite and greywacke of the Jurassic to Cretaceous Leech River Complex. These have been intruded by felsic dikes and diorite sills.

Locally, a felsic dike hosts disseminated to blebby pyrite and arsenopyrite mineralization.

In 2008, the area was prospected as the San Juan Ridge claim by Le Baron Prospecting. A rock chip sample (H031119) from the dike assayed 9.15 grams per tonne silver and 0.116 per cent copper (Assessment Report 30983).