The Silver Basin occurrence is located west and downhill from the Granduc Mine Road in the north wall of a small canyon that drains to the southwest onto the Salmon Glacier, approximately one kilo- metre west-northwest of the Big Missouri deposit. This showing is probably located in one of the two creeks that parallel Hercules Creek 800 metres north of stated location (Personal Communication D. Alldrick Jan. 1989).

Located in the Intermontane Belt, the area, bounded on the west by the Coast Crystalline Complex and on the east by the Bowser Basin, is part of the volcanic arc assemblage of the Stikinia Terrane.

Mineralization is hosted by the Upper Triassic to Lower Jurassic Hazelton Group, Unuk River Formation metavolcanics. 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 the Early Jurassic Texas Creek plutonic suite of dacitic porphyry dykes.

The Silver Basin showing is hosted in argillites of the Upper siltstone member of the Unuk River Formation. Mineralization occurs in shattered argillites as stringers of quartz, calcite, galena, sphalerite and some pyrite. A chip sample over 1.1 metres assayed trace gold, 102.84 grams per tonne silver, 7.8 per cent lead and 4.6 per cent zinc (Minister of Mines Annual Report 1929).

Work History

The Silver Basin group was owned and prospected by the Fitzgerald Brothers, of Hyder, Alaska, from about 1929 to about 1935. Most of the work was done at about the 980 metres elevation and included open cutting, and a 20 foot long adit driven north 64 degrees east.

Mineralization was reported in 1929 the Silver Basin claim. In 1935, the Silver Basin Group included the Last Chance claim (104B 358) where newer work had occurred, apparently after the 1929 work done on the Silver Basin showing. The locations of both occurrences are not well understood.

An airborne geophysical survey was carried out in the area on behalf of Atna Mines in 1969 (Assessment Report 2320).

In 1991, Westmin Resources had an airborne magnetic and electromagnetic survey conducted over the Premier Gold property totalling 760 kilometres (Assessment Report 21993). This survey covered an extensive area from the south end near the Premier mine area, north to the Yellowstone (104B 039) area. The area includes the Amber-Silver Basin area.

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.

See also Yellowstone (104B 039) and Premier (104B 054) for related details of the Dilworth and Premier properties that were held as a single entity in the 2000s by Boliden and Ascot Resources. Also see Big Missouri (104B 046) for historical work in the immediate vicinity.