The Gros occurrence is located at an elevation of approximately 900 metres, west of Sam Ross Creek and north of a small lake.

The geology of the region consists of: 1) a Mississippian to Triassic Cache Creek Group oceanic volcanic and sedimentary assemblage 2) the Upper Triassic dominantly mafic volcanic Takla Group 3) the Lower to Middle Jurassic Hazelton Group mafic to felsic volcanic and sedimentary rocks 4) the Upper Cretaceous to Lower Tertiary Ootsa Lake Group sedimentary and volcanic rocks and 5) the Oligocene and Miocene Endako Group. The region has been intruded by the Lower Jurassic quartz monzonite to granodiorite Topley Intrusive Suite, Upper Jurassic plutons of the Francois Lake Suite and plugs and stocks related to Upper Cretaceous and Tertiary volcanism.

The Gros showing consists of pyrite and fluorite mineralization which occurs in silicified fractures cutting volcanics of the Ootsa Lake Group. These rocks overlie quartz monzonite to quartz diorite of the Francois Lake Intrusive Suite.

Work History

During 1963 through 1967, Amax Exploration Ltd. completed programs of biogeochemical, water, rock, silt and soil sampling, geological mapping, a 20.2 line-kilometre ground magnetic survey and 15.3 line-kilometres of induced polarization survey on the area as the Lorne claims of the Sam Ross Creek property.

In 1979, Placer Development Ltd. completed a program of geological mapping, soil sampling and a 22.0 line-kilometre ground scintillometer survey on the area as the Rain claims.

In 2007, Nation River Resources Ltd. completed a program of rock, soil, and water sampling on the area as the MO and SR claims. Five rock samples (NR-07-02R, -04R, -06R, -07R and -08R) yielded from 0.110 to 0.197 per cent fluorine (Assessment Report 29350).