Three stratigraphic assemblages have been mapped in the area: (1) Upper Palaeozoic sediments and volcanics of the Stikine Assemblage, (2) clastic sediments of the Triassic Stuhini Group, and (3) Lower Jurassic sediments and volcanics of the Hazelton Group.

Four plutonic suites intrude the above; (1) Late Triassic calc-alkaline intrusions coeval with Stuhini Group stratigraphy, (2) Jurassic Copper Mountain, (3) Jurassic Texas Creek and (4) Tertiary Coast Plutonic suite.

Mineralization at the SMC prospect occurs as volcanogenic massive sulphide but is also shear-hosted (Assessment Report 29673). Mineralization has been traced over a 160 metres strike length in the trenches and follows a north-northwest trend. Rock types described include intermediate to felsic tuffs to lapilli tuffs within more extensive wackes and siltstones. Massive sulphides are well laminated within the tuffs. Sphalerite and pyrite are the dominant sulphides with lesser galena and chalcopyrite. Sulphides also occur as veinlets within brecciated felsic tuff subparallel to foliation/bedding. Silicification is strong where metal grades are highest. Foliation and shearing attitudes are highly variable but drilling shows bedding and mineralization to be dipping moderately northeast.

At the SMC showing, silicified structures grade up to 14.7 grams per tonne gold, 16.4 grams per tonne silver and 1 per cent lead and zinc over 1 metre (Assessment Report 28103).

Work History

The SMC Showing was discovered in 1988 during construction of the road leading from Bronson Airstrip to the Johnny Mountain mine. A single drill hole was completed at that time. Showing exposures were increased in size by four back-hoe trenches. Twelve diamond drill holes were completed on a very tight grid along 40 metres of strike length in 1991. Drill results yielded many mineralized sections with grades similar to the trench samples and with better grades. One hundred and twenty-five channel samples were collected by Adrian Resources Ltd in 1991 by making two cuts about 5 centimetres apart with a carbide blade across outcrops and chiselling out the intervening rock. A single diamond drillhole directed beneath the SMC structure by Spirit Bear Minerals in 2007 failed to show continuity of mineralization to depth, probably as a result of fault complications.

Refer to Johnny Mountain (MINFILE 104B 107) for related details and common property work history.