The Cornice Mountain Breccia occurrence is located approximately 1 kilometre northwest of the summit of Cornice Mountain.

The area is underlain largely by north-striking near-vertical Early Jurassic Lower Hazelton intermediate volcanic and volcanogenic sedimentary rocks. This volcanic pile has been intruded by hypabyssal intrusions, some of which are of similar, and consist of feldspar porphyry and rhyolite domes. These intrusions are found at Cornice Peak and Yvonne Peak and are interpreted as volcanic centres. The rhyolitic domes, dykes and welded tuffs are believed to represent late stage silicic volcanism in the evolving island arc.

Locally, a 15 to 20 -metre wide breccia zone has been identified over a strike length of 50 metres and along a cliff face for at least 70 metres of vertical extent. The zone occurs at the intersection of two prominent structures, striking 090 and 140 degrees, respectively. The zone comprises clast-supported breccia and crackle breccia with silicified volcanic clasts occurring within a quartz-calcite-massive sulphide matrix. Sulphide mineralization comprises primarily sphalerite, pyrite and chalcopyrite with minor galena and arsenopyrite. Gossanous zones extend along a structure to the west for an additional 300 metres.

During 2005 through 2010, Auramex completed programs of prospecting, geological mapping, geochemical sampling and airborne geophysical surveys on the area as the Bear River-Surprise Creek property. In 2010, a chip sample assayed 6.78 grams per tonne gold and 2.24 per cent zinc over 14.5 metres, while another sample yielded 11.1 grams per tonne gold over 6 metres (Metcalfe, P. (2013-08-17): Technical Report – Bear River-Surprise Creek Property).