The Key occurrence area is underlain by Early Jurassic-Late Triassic Guichon Creek batholith quartz diorites to granodiorites. Border phase rocks to the west are in contact with Guichon variety rocks to the east. Mineralization is described only as chalcopyrite, bornite and molybdenum; the exact location of the mineralization ambiguous. An assay returned 0.2 per cent copper (Assessment Report 6488).