The Howe Copper North West (Slippery Lake) occurrence is located on a ridge to the north east of Slippery Lake and northwest of Mount Donaldson. The Howe Copper (MINFILE 092GNW005) occurrence is located approximately 700 metres to the southeast.
The area is predominantly underlain by biotite and hornblende-biotite granite of the Jurassic to Cretaceous Coast Plutonic Complex. Intruding these, and incorporating blocks of the biotite granite, is a sugary textured, fine to medium- grained, vuggy muscovite granite. Drusy quartz crystals often line the vugs. The muscovite granite has a potassium-argon age date of 83 million years, Late Cretaceous ( Geological Survey of Canada Open File 611). Locally, several linear outcrops occur, comprised of bedded lapilli tuff or tuffaceous rock striking northeast with moderate dips northwest.
The most prominent feature of the property is the masses of quartz and quartz veins that criss-cross the area. At least three sets of veins are recognized in association with major joints. Two areas of locally widespread and irregular quartz masses are also evident. The veins commonly pinch and swell and appear discontinuous in length. The quartz occurs in the form of milky to translucent masses and crystals. Larger veins are vuggy and often filled with drusy quartz, various copper minerals and muscovite. A persistent mineral constituent of the quartz veins is a muscovite mica, which occurs primarily along the selvage of the veins; it also occurs as massive books completely enveloped by the quartz and lining the vugs and cavities. Small aplitic dikes, 2 to 10 centimetres in width, transect the area and are locally parallel to the strike of the joint systems.
The intrusive rocks are well jointed in at least two directions; the dominant joint striking east with steep north and south dips and the secondary system striking 020 degrees and dipping almost vertically.
Locally, a trench has exposed two quartz-muscovite-feldspar veins, varying from 0.2 to 0.3 metre in width, hosting disseminated to massive tetrahedrite, chalcopyrite, bornite and chalcocite mineralization with associated malachite and azurite staining. The mineralized veins have been exposed by trenching for up to 20 metres.
In 1983, a sample (09) from the trench assayed 56.59 per cent copper and 833.5 grams per tonne silver (Assessment Report 11619).
In 1991, a sample (PR90-15) from the trench yielded greater than 1 per cent copper, greater than 200 grams per tonne silver, and 0.70 gram per tonne gold (Assessment Report 22242).
Nearby, a pit exposes a small quartz- muscovite vein striking 273 degrees and dipping 80 to 85 degrees north. Mineralization consists of bornite, chalcocite and chalcopyrite closely associated with muscovite. Accessory magnetite was locally observed. In 1991, a sample (PR90-19) assayed greater than 1 per cent copper, 98.6 grams per tonne silver and 0.18 gram per tonne gold (Assessment Report 22242).
The area has been explored in conjunction with the nearby Howe Copper (MINFILE 092GNW005) occurrence since its discovery in 1874 by Howe Sound Mining Company. In 1965, Bralorne Resources completed a program geological mapping, trenching, stripping and geochemical sampling on the area as the Zel Group. In 1967, Grasset Lake Mining completed approximately 750 metres of diamond drilling. No information regarding drilling results was reported. In 1972, Athena Mines completed a 72.0 line-kilometre airborne geophysical survey on the area as the Karen 1-16 claims. In 1980 and 1983, Seatac Resources completed programs of geological mapping, rock sampling and a 6 line-kilometre combined ground magnetic and electromagnetic survey on the area as the Anthony 1-8 claims. In 1988 and 1990, programs of prospecting, geological mapping and rock sampling were completed on the area as the CU 1-4 claims. In 2004, the area was prospected by Laird Exploration as the HC 1-4 claims for valuable quartz crystal specimens. In 2006, Copper Road Resources prospected the area.
