The Bolivar occurrence area is underlain by Upper Triassic Quatsino Formation limestone in an interdigitating contact with Karmutsen Formation basalt, both formations of the Vancouver Group. An irregular wedge, thinning to the northwest, of siliceous skarnified rock follows a structure that roughly parallels the limestone/basalt contact. Some disseminated pyrite and minor chalcopyrite occurs within this unit and along the contact with the basalt and limestone. The basalts are thick bedded, amygdaloidal and massive flows which locally are epidotized and cut by quartz veins. The quartz veins range from a fraction of a centimetre to 50 centimetres or more in width and commonly contain pyrite and lesser amounts of pyrrhotite and chalcopyrite. Local intense zones of epidotization are accompanied by some silicification with associated pyrite, pyrrhotite and chalcopyrite. The limestone is mainly fine-grained and grey and cut by numerous basaltic dykes. Local zones within the limestone show varied intensity of recrystallization to marble. Black carbonaceous (graphitic) material occurs in pockets, along sinuous partings and along the outer margins of the recrystallized zones.

Native gold occurs as streaks and disseminations along subparallel graphitic slips in a sheeted zone of variably recrystallized limestone. Pyrite is also present but is most abundant in the carbonaceous material. The gold-bearing zone is 41 metres long, 3 metres wide and extends to a depth of 15 metres. Diamond drilling has indicated north dipping stratigraphy and a mylonitic contact zone with footwall basaltic volcanics. A sludge sample of drill core assayed up to 1.9 grams per tonne gold with minor values in silver (Assessment Report 11826).

Diamond drilling has also revealed that silver values are associated with stringer-type sphalerite veinlets, pyrrhotite and minor chalcopyrite in a graphitic shear zone in limestone elsewhere on the property.

A 1734 tonne bulk sample from the Bolivar pit returned a total of 1031.14 grams of gold (Assessment Report 16702). Ore has subsequently been mined from the Bolivar pit where initial mill feed graded 5.14 grams per tonne gold (George Cross Newsletter #89, 1987).