The Hattie occurrence is hosted by a sequence of the Lower Jurassic Elise Formation (Rossland Group) consisting of greenstone, volcanic breccia, conglomerate and sandstone. The Hattie mineralization is considered to be a Rossland-type ore which is hosted by Rossland Group rock and located 400 metres south of the southern edge of the Early Jurassic Rossland Monzonite. The monzonite has recently been dated at 190 million years (Andrew, K.P.E., Personal Communication, March, 1991). The showing lies within the zone of thermal metamorphism associated with the monzonite intrusion.

The Hattie vein system consist of fissure filled veins in the Rossland volcanics which host abundant arsenopyrite, chalcopyrite, and pyrite. Pyrite occurs as disseminations in the host rocks as well as in veinlets which crosscut the stratified host rock. The gangue consists mainly of altered host rock with minor lenses of quartz and calcite. The main vein strikes east-west and dips 85 degrees south to vertical. The vein averages 7.6 centimetres in width. A sample taken across 30 centimetres assayed 11.31 grams per tonne gold, 181.72 grams per tonne silver and 5.02 per cent copper (Minister of Mines Annual Report 1921, page 151). In 1980 a series of east-west stacking veins were exposed dipping 75 degrees south. In 1967, Thorpe reported that native gold, bismuth and associated bismuthinite occurs in the ore.

Between 1934 to 1939, 21 tonnes of ore was mined from the Hattie vein system and 310 grams gold and 1090 grams silver were recovered.