The Chalco showing of the Cole property area is underlain by a sequence of volcanic and sedimentary rocks of the Lower Jurassic Telkwa Formation of the Hazelton Group. Host rocks consist of thick-bedded purple to green lapilli tuffs and volcanic breccias dip steeply northwest and are commonly cross-cut by intermediate dikes. Black mudstone and siltstone occur in the vicinity.
The Chalco showing is associated with a northwest trending system of veins that contains both northwest trending veins and north to northeast trending veins. It is an acutely branching array of veins that split, splay and horsetail. It is an acutely branching array of veins that split, splay and horsetail. The individual veins are associated with minor shears, and pinch and swell from stringer-stockworks to masses up to and in excess of 3 metres width. Veins dip steep (60 degrees) to vertical. The overall mineralized vein system is traceable intermittently for in excess of 4 kilometres. Vein quartz types include massive, banded, vuggy and coxcomb quartz generally white in colour but locally beige, grey, clear, red and rarely amethystine. At least 10 discrete zones or showings have been documented and sampled over part of the 4 kilometre length. Most of the showings are low in sulphides containing less than 1 per cent pyrite, locally to 15 per cent.
The Chalco showing was discovered in 1984, the result of follow-up on fluorite bearing quartz boulders noted in 1983. The showing consists of a northwest trending quartz vein occupying the base of the slope above extensive talus wash. Trending off this vein, in a north-easterly direction, are a series of veins, stringers, and silicified and propylitized alteration pods that carry pyrite and chalcopyrite. From one of these zones, measuring up to 1 metre width, a grab sample assayed 24.0 grams per tonne gold (Assessment Report 14531). Other values from this zone assayed 0.73 and 0.34 gram per tonne gold and up to 24 grams per tonne silver (Assessment Report 14531). Refer to Main Creek showing (093E 110) for further geological and work history details.