The Mount Skinner occurrence comprises gold and copper mineralization, 5 kilometres north of the northern end of Tatlayoko Lake. Work has been done in this area intermittently since the early 1900's.
The occurrence is located 5 kilometres southwest of the northwest-striking Yalakom fault, in part of the Cadwallader Terrane (Geological Survey of Canada Open File 1163, Map 1713A). The area is dominated by a quartz diorite to diorite intrusion of uncertain age, but it is probably related to the Jurassic to Tertiary Coast Plutonic Complex. The intrusion is hosted by Lower to Middle Jurassic sedimentary rocks to the south and west, partly in fault contact (Geological Survey of Canada Open File 1163). To the north of the intrusion are Upper Triassic sedimentary rocks.
Most of the Skinner property is underlain by the quartz diorite intrusion (Assessment Report 21396). Numerous mafic, intermediate and felsic dykes, up to 3 metres thick, intrude the quartz diorite. Sporadic chlorite-epidote alteration is present in the intrusion. Andesitic flows and tuff occur locally but it is not clear what unit these volcanics are related to.
The Skinner occurrence is centred on a mesothermal quartz vein in the intrusion called the Victoria vein (Assessment Report 21396). The length of the vein is undetermined but is at least 125 metres long, of which 110 metres has been exposed by hand trenching. The vein pinches and swells and appears to be fault controlled; the lineament is discernible on aerial photographs. The vein is up to 1.4 metres in thickness, and strikes between 050 and 070 degrees, dipping at least 70 degrees northwest. The host quartz diorite is moderately silicified and chloritized adjacent to the vein, and some argillic alteration is present.
The Victoria vein contains up to 5 per cent pyrite, with a trace of chalcopyrite, locally associated with malachite on fracture surfaces. Fractures are common and are rich in limonite and also hematite. Native gold occurs on some fracture surfaces, or within vuggy cavities, and as fine disseminations; visible gold was found in two places in the vein, 75 metres apart. Sericite is commonly associated with the quartz.
The length-averaged (110 metres) grade of the vein is 29.6 grams per tonne gold, over a 1.0 metre average width, or 20 grams per tonne gold diluted to a 1.5 metre width (George Cross News Letter, June 1991). The best value from surface chip sampling (presumed assay) of the Victoria vein is 58 grams per tonne gold over 1.4 metres (Property File - Berniolles, L.M., 1991). The best drill intersection is 62.4 grams per tonne gold over 1 metre at a depth of 32 metres (Property File - Berniolles, L.M., 1991). The host diorite has been assayed at up to 4.1 grams per tonne gold (Vancouver Stockwatch 1991).
A 0.25-metre thick quartz vein, a possible extension of the Victoria vein 400 metres along strike to the east-northeast, assayed 14 grams per tonne gold over its width (Assessment Report 21396).
Current indicated reserves are 11,800 tonnes of 16 grams per tonne gold (Property File - Berniolles, L.M., 1991).
Elsewhere on the property, rock and soil geochemical values are generally low, although one sample of a fractured, silicified and propylitically-altered dyke with 1 per cent malachite was analysed at 2 per cent copper (Assessment Report 21396).
A 172-tonne bulk sample from the Victoria vein yielded 11,351 grams of gold (Northern Miner - June 6, 1994).