The Deer Park occurrence is hosted by greenstone, volcanic breccia, conglomerate and sandstone sequence of the Lower Jurassic Elise Formation, Rossland Group. The mineralization is considered to be a Rossland-type ore that occurs within the contact aureole of the Early Jurassic Rossland monzonite. The Rossland Monzonite has recently been age dated at 190 million years and consists of a biotite-hornblende-augite monzonite stock. The mineralized veins are considered as part of the South belt vein system. Refer to the Le Roi deposit (082FSW093) for a summary of the Rossland mining camp.

Mineralization consists of massive to semi-massive, pyrite, pyrrhotite and magnetite along the monzonite contact. Abundant fib- rous radiating masses of actinolite in a magnetite skarn occur near the massive ore. The low-grade massive pyrrhotite-magnetite ore carries a little copper with traces of gold.

A quartz vein network associated with the monzonite hosts mostly pyrite with some arsenopyrite and free gold, minor calcite, chalco- pyrite, molybdenite and scheelite. The arsenopyrite is nearly always cobaltiferous approaching a danaite composition, and shows unusual twinning in crystals found in the Deer Park veins. The vein system strikes 170 degrees and dips steeply to the north. In 1967, Thorpe identified kobellite, a lead-bismuth sulphide, in the ore from the Deer Park mine. This mineral is a rare sulphosalt, and blades of the kobellite are enclosed in the coarsely granular vein quartz, which also includes minor pyrite, arsenopyrite, pyrrhotite, and chalcopyrite.

The vein system, or ore shoots, terminate abruptly against cross structures. There are several lamprophyre dykes or spessartite dykes with large phenocrysts of hornblende and biotite which traverse the country rock and dissect mineralized ore shoots.

By 1899, 600 metres of underground development had occurred and 16 tonnes of ore had been shipped (Minister of Mines Annual Report 1899, page 599). Statistics on the recovery of minerals from the ore were not reported.