The Higrade area underlain by Lower Jurassic Telkwa Formation (Hazelton Group) volcanics. The volcanics are predominantly tuffs, agglomerates and grey to green andesites. Minor porphyritic (plagioclase and/or hornblende) flows and interflow sedimentary rocks are also present. The volcanic rocks are intruded by narrow quartz feldspar porphyry dikes which are 1 to 3 metres wide and strike northeast. The dikes, fine to medium-grained, are possibly related to the Eocene Kastberg Intrusions.
The Higrade occurrence consists of quartz-carbonate veining containing massive grey-sulphide mineralization (possibly tetrahedrite or argentite), chalcopyrite, and malachite. One grab sample (RR96-22) assayed 2.31 grams per tonne gold, 31.0 grams per tonne silver, and 3.68 per cent copper (Assessment Report 24882, page 16, Figures 5a, b and c). Another rock sample (RR96-21), 350 metres to the west-northwest, graded 8.62 per cent copper and 397.6 grams per tonne silver (Assessment Report 24882, Figures 5a, b and c). Nearby mineralized float (WR96-5) collected at the same time in this area in 1996 graded 10,530 grams per tonne silver and 36.9 per cent copper (Assessment Report 24882, page 16, Figures 5a, b and c). The sample was from a massive grey-sulphide mineralization in quartz-carbonate vein material in a talus slope.
Refer to Bearnx (094D 003) for related geological information and a common work history.