The Cheam Mountain occurrence is located on the northern slopes of Cheam Mountain at an elevation of 540 metres, approximately 1.5 kilometres south of the Fraser River.
The area is underlain by pelites and sandstones of the Triassic and/or Jurassic Cultus Formation, which in turn overlie volcaniclasitic sediments, limestone and volcanics of the Devonian to Permian Chilliwack Group. These rocks are intruded by the Miocene Mount Barr batholith composed of granodiorite and quartz diorite.
Locally, limestone bluffs of the Chilliwack Group contain two irregular, parallel and vertical, vuggy quartz veins, up to 2.1 metres wide and 15 metres apart, which trend south up the face. Within the veins are scattered veinlets of chalcopyrite and irregular masses of pyrrhotite. Some sulphide extends into the limestone wallrock. The limestone is crystalline and in spots is altered to garnet.
A 2.1 metre channel sample taken across one of the veins yielded 0.11 per cent copper and no silver and gold (Minister of Mines Annual Report 1966, page 61). Other samples yielded traces of gold and tungsten.
In 1973, work was apparently performed at this location as the Lucky claims, where iron, copper and zinc mineralization were noted at a limestone-granite contact. In 1984, the area was prospected and sampled as the Pop claims. During 1989 and 1990, the area was prospected by New Global Resources. In 1996, the area was prospected by Steelhead Aggregates.