A band of Permian limestone of the Devonian to Triassic Harper Ranch Group extends northwest for 4.8 kilometres along the southwest side of Camel's Hump, an elongate hill located 7.5 kilometres east-southeast of Lumby.

The band averages greater than 800 metres in width. The limestone is bounded by sandstone and argillite to the southwest and volcanic flows to the northeast. Bedding strikes 102 to 112 degrees and dips 45 to 70 degrees south (Geological Survey of Canada Map 1059A). The band consists of medium to fine grained, light to dark grey limestone containing some argillaceous streaks and inclusions of black chert. The rock is occasionally brecciated and healed with white calcite.

A sample of chips taken randomly over the band analyzed 52.16 per cent CaO, 0.48 per cent MgO, 3.84 per cent insolubles, 0.82 per cent R2O3, 0.50 per cent Fe2O3, 0.07 per cent MnO, 0.03 per cent P2O5, 0.01 per cent sulphur 42.05 per cent ignition loss and 0.13 per cent water (Minister of Mines Annual Report 1961, page 148, Sample 10).