The Mix workings are underlain by thinly bedded argillaceous and cherty metasediments of the Mississippian to Jurassic Bridge River Complex (Group). Intercalated with the northwest striking, northeast dipping sediments are lenticular greenstone bodies. Highly metamorphosed, massive greenstone bodies a few metres thick are also reported; these are probably dykes "feeding" the main Upper Triassic Pioneer Formation (Cadwallader Group) greenstone body located to the northeast. Alongside these "dykes", shearing and faulting occurs nearly parallel with the enclosing metasediments. A southeast trend- ing drift follows a fissure for 54 metres containing quartz in irreg- ular, small deposits as veins and partial wallrock replacements. Sparse iron sulphides are reported with gold values up to 10.28 grams per tonne (or $6 per tonne in 1937) (Geological Survey of Canada Memoir 213, page 107).