The Southern Belle claim lies within the Lower Jurassic Rossland Group (Elise Formation) augite porphyry, known as the Rossland sill. The sill lies beneath siltstone and hornfels and is exposed on the eastern slopes of Red Mountain. The augite porphyry is a uniform dark green rock with phenocrysts of augite up to 3 millimetres across. The upper contact is planar and dips about 20 degrees west, concordant with the bedding of the siltstone and hornfels of the Rossland Group. Several narrow dykes or sills of augite porphyry occur within the hornfels which is rich in hornblende and dis- seminated magnetite. The augite porphyry appears to be intrusive into the siltstones and to have a narrow thermal contact metamorphic zone of hornblende-magnetite hornfels.

The Rossland Group rocks are intruded to the south by the Early Jurassic Rossland monzonite stock and to the north by the Middle to Late Trail Pluton which is comprised of a granodiorite stock.

The Southern Belle adjoins the Cliff and Consolidated St. Elmo claims to the north (082FSW135 and 136). The country rock is augite porphyry. A vein, up to 30 centimetre wide, hosts auriferous pyrr- hotite and pyrite and in 1915 was reported to assay about 33 grams per tonne gold (Geological Survey of Canada Memoir 77, page 134). By 1915, a prospect shaft had been sunk on a 0.6-metre wide pyrite vein with strike of 077 degrees and dip of 80 degrees north. A lower tunnel discloses the same pyrite vein in the form of three bands of low grade pyrite 15, 30 and 5 centimetres in width, respectively.