Foliated greenstone of the Upper Triassic Pioneer Formation Cadwallader Group is faulted against metasediments consisting of meta-argillite and quartzite of the Mississippian to Jurassic Bridge River Complex (Group). Trending north along the faulted contact lies a sinuous body of Permian and older serpentinized peridotite of the President Ultramafics, and diorite and granodiorite of the Cretaceous to Tertiary Bendor pluton.

Narrow, 2 to 20 centimetre wide, vuggy quartz veins trend north-northeast and crosscut all rock types. Disseminated pyrite is common and forms intense gossans in the granodiorite. All veins carry minor amounts of pyrrhotite and molybdenite. Along the north side of the periodotite-serpentinite intrusion, quartz veins carrying mariposite and carbonate-talc alteration occurs.