The Extreme showing is located on the eastern side of the Salmon Glacier, approximately 1.5 kilometres northwest of Noname Lake.

The area is underlain by metavolcanics of the Lower Jurassic Unuk River Formation, Hazelton Group. The Hazelton Group is a northwest trending steeply east-dipping belt of folded andesitic lapilli tuffs, flows and breccia containing a thick sequence of argillite and siltstone infolded along a synclinal axis. The sequence is intruded by Early Jurassic Texas Creek dacitic porphyry dikes.

Locally, narrow mineralized quartz veins hosting disseminations of pyrite, sphalerite, chalcopyrite, and galena within a dacite porphyry-diorite-granodiorite host rock. Grab sampling from the Extreme yielded up to 0.28 gram per tonne gold, 115.0 grams per tonne silver, 0.18 per cent copper, 0.58 per cent lead and 1.10 per cent zinc (Assessment Report 21810).

The Extreme showing was re-examined by Westmin in 1992 and was reported to comprise outcropping and subcropping of mineralized quartz-carbonate veins. At least three subparallel veins occur with individual veins up to about 50 centimetre in width. Veins strike from 158 to 190 degrees and dip 38 to 55 degrees west. Previous sampling yielded assays of up to 2.33 grams per tonne gold 816 grams per tonne silver and 14.4 per cent copper (Assessment Report 22705).

In 1989 Homestake Mining found the Ice showing, located about 250 metres north of the Extreme showing (Assessment Report 19294). The showing consists of a 7-centimetre-wide quartz vein carrying 5 to 30 per cent sulphides including pyrite, sphalerite, galena and chalcopyrite. It is exposed over a length of 10 metres and is covered by talus at one end. A quartz-sulphide stringer zone occurs adjacent to the vein. Westmin plots a showing at the same location on map 3C which documents work in 1992 (Assessment Report 22705).

Work History

Between 1987 and 1992, Westmin Resources and Homestake Canada completed programs of soil sampling, geological mapping and prospecting.

The Extreme showing was initially discovered by Homestake geologists in 1987. It occurred in talus from a nearby source. In 1990, Westmin reported the showing as being located approximately 300 metres below the Granduc Road and (was) 600 metres north of the toe of the Salmon Glacier. Mineralization was found in large talus blocks and outcrop near the top of a steep slope at the base of a cliff. Westmin returned to the area in 1992 and conducted a program of geological mapping, prospecting and lithological mapping. The M&M (104B 478), Zahorec (104B 479), and Canada (104B 477) showings were also examined.

During 2004 through 2019, the area has been explored as part of the Silver Coin property and a complete property exploration history can be at the nearby Silver Coin (MINFILE 104B 150) occurrence.