Two northeast trending, parallel limestone lenses 770 metres apart, each 1.8 kilometres long, outcrop as two cliffs along the east flank of Jamieson Range, 35 kilometres north of the community of Kamloops. The lenses are hosted in a succession of argillite, quartzite and mafic volcanics of the Carboniferous to Triassic Harper Ranch and/or Nicola groups.

The two lenses are made up of light grey to white, medium to fine-grained limestone with scattered patches of chert. A sample taken along the base of the bluff of the northern lens for 152 metres analysed 54.54 per cent CaO, 0.08 per cent MgO, 1.70 per cent insolubles, 0.18 per cent R2O3, 0.10 per cent Fe2O3, 0.025 per cent MnO, 0.017 per cent P2O5, nil sulphur and 43.28 per cent ignition loss (Minister of Mines Annual Report 1959, page 170, Sample 6).