The Jan showing is located near the eastern margin of the Stikinia Terrane in south central British Columbia. The dominant rock types in the region are metabasalt, limestone and argillaceous metasediments of the Mississippian to Triassic Cache Creek Group. These are intruded by the dioritic to quartz dioritic Granite Mountain Pluton and the (?)Cretaceous Sheridan Creek Pluton. The Granite Mountain Pluton has been affected by regional metamorphism (greenschist facies) and deformation along with the enclosing Cache Creek Group.

Located immediately to the west of the GR showing (093B 017), the Jan showing is underlain by volcanic rocks of the Cache Creek Group and intrusive rocks of Granite Mountain type. Chalcopyrite and molybdenite occur within quartz diorite associated with chloritic and sericitic alteration zones.