The Summit occurrence is located in the head waters of Fossli Creek, approximately 2.8 kilometres south of the creek mouth and 9.5 kilometres west-southwest of Port Alberni.
The area is underlain by Lower Jurassic Bonanza Group volcanics and limestone of the Upper Triassic Quatsino Formation, Vancouver Group.
Locally, a pyrite-stained outcrop consisting of a mixture of soft brown volcanic rock and quartz, and mineralized in a narrow zone with malachite and azurite, is thought to be a breccia. A few hundred metres to the north mineralized volcanic is reported to contain 0.02 per cent copper (Assessment Report 5650). Float containing chalcopyrite was also reported.
In 1974, W. Guppy completed a program of prospecting including rock and soil sampling on the area as the Summit claim. In early 1987, the area was prospected by Triactor Resources. In late 1987 and 1988, Veto Resources completed a program of rock and soil sampling, geological mapping and a ground magnetometer survey on the area. In 1989 and 1990, Simplon Resources completed a program of rock sampling and geological mapping on the Foss 1-2 claims. SYMC Resources Limited explored the area in 1998 to 2006 as part of their Dauntless (Macktush) property. In 2009 through 2011, G4G Resources completed programs of geological mapping and rock and soil sampling on the area as the Macktush Copper property. In 2012, Nahminto Resources Ltd. completed a satellite remote sensing survey and analysis on the Macktush group and continued programs of prospecting, geological mapping and rock sampling from 2012 through 2014. A similar prospecting, geological mapping and rock sampling program was conducted on areas of the Macktush property for World Organics Inc. in 2015.