The host rocks are comprised of Lower Jurassic Hazelton Group volcanics of the Telkwa Formation. They consist mainly of andesite, breccia, andesitic flows, spherulitic flow-banded rhyolite and massive lapilli tuff.

In the Coronado Group, mineralization is associated with two parallel shear zones in the rhyolite, andesitic flows, and flow breccia. The zones are approximately 290 metres apart and strike 045 degrees and dip between 75 to 85 degrees southeast.

The westerly zone was prospected by 3 adits along strike across the Coronado and Home Run claims. The lower adit, No. 1, exposed a single sparsely mineralized fissure. It was followed for 6 metres where it branched into two fissures. The host rock is silicified rhyolite and is cross fractured with crosscutting veinlets of sulphides comprised mainly of arsenopyrite. A 91 centimetre channel sample taken across the face assayed 1.2 grams per tonne gold, and 21.6 grams per tonne silver.

No. 2 adit along the shear hosted sulphide mineralization consisting of argentiferous galena, arsenopyrite, sphalerite with minor tetrahedrite and chalcopyrite. A selected sample of this ore assayed 12.3 grams per tonne gold, 708.3 grams per tonne silver, 16.96 per cent lead, and 12.06 per cent zinc (Geological Survey of Canada Memoir 233, page 92 - revised edition).

The No. 3 adit showed sparse mineralization in the shear. However, in an open cut further east, at 1100 metres elevation, cross fractured and silicified flow breccia hosted disseminated arseno- pyrite.

Production between 1915 to 1940, from the mineralized shear vein fillings on the Coronado and Home Run claims totalled 128 tonnes mined which produced 1,275 grams gold, 242,541 grams silver, 45,490 kilograms lead, and 7,148 kilograms zinc.