The deposit is part of the "Main vein" system, in the Rossland mining camp, which forms a continuous well defined fracture system on a regional scale. The Main vein system trends 70 degrees for a strike length in excess of 1.0 kilometre with the veins dipping steeply to the north. Refer to the Le Roi deposit (082FSW093) for a more detailed discussion of the regional geology and the Main vein system.

The Nickel Plate vein system is hosted by the Early Jurassic Rossland monzonite and augite porphyry of the Lower Jurassic Elise Formation (Rossland Group), known as the Rossland sill. The Rossland monzonite is an east-trending stock of biotite-hornblende-augite monzonite. Tertiary lamprophyre dykes, trending northwards, crosscut the monzonite and sill. This dyke is about 70 metres thick and gives a potassium-argon date of 49.6 plus or minus 1.6 million years (Bulletin 74). The dyke appears to control the concentrations of copper and copper-gold ore. It is a dark greenish dyke with pre-dominant crystals of biotite and abundant potassic feldspar. Minor serpentine occurs on blocky joint faces which caused unstable ground when driving the adit.

Sulphide mineralization occurs from the replacement of wallrock along well defined fractures and by infilling fractures and faults with pyrrhotite and chalcopyrite. The gangue consists of minor lenses of quartz and calcite. Minor pyrite occurs as crystals in the pyrrhotite and as disseminations in the host rock.

In 6 years between 1901 and 1913, 18,685 tonnes of ore were mined from the Nickel Plate vein system with recovery totalling: 291,778 grams of gold, 335,787 grams of silver and 209,376 kilograms of copper.