The Couloir showing occurs near the regionally mapped northwest trending contact of Lower Jurassic Takwahoni Formation (Laberge Group) andesitic rocks, on the south, and an Upper Triassic Stuhini Group sedimentary package consisting of argillite, greywacke, wacke and conglomerate turbidites, on the south. Volcanic rocks of the Upper Triassic Stuhini Group are mapped several hundred metres to the northwest of the plotted Couloir occurrence.
The Couloir showing occurs along a major structure close to the contact of two volcanic
packages. It consists of a 30 centimetre wide pod or vein of massive pyrrhotite,
chalcocite, sphalerite and arsenopyrite in felsic volcanics and in close association with
limestone. The felsic rocks in the area have more recently been determined to be altered andesitic rock.
A sample is reported to have assayed 7.68 grams per tonne gold, 63.8 grams per tonne silver, 0.26 per cent copper, 2.64 per cent zinc and 11.31 per cent arsenic (Assessment Report 18803).