The Royal Crown showing is located at the junction of the Moyie River and Ridgeway Creek (Minister of Mines Annual Report 1929). Small galena lenses in a pegmatite stringer or vein occur in a Moyie diorite intrusion within Aldridge Formation quartzites and argillites (Middle Proterozoic Purcell Supergroup). At the quartzite-diorite contact a small patch of chalcopyrite-pyrite occurs.