Fine grained, grey limestone of the middle to Upper Permian Marble Canyon Formation (Cache Creek Complex) outcrops at the north end of a small ridge trending north-northwest in the headwaters of Maiden Creek, 38 kilometres northeast of Lillooet. Bedding is subparallel to the ridge. A sample of this rock analysed 53.90 per cent CaO, 2.45 per cent MgO, 0.46 per cent SiO2, 0.50 per cent Al2O3, 0.11 per cent Fe2O3, 0.02 per cent TiO2, 0.02 per cent Na2O, 0.02 per cent K2O, 0.02 per cent P2O5 and 43.49 per cent ignition loss (B.C. Hydro Report SE 8117, Table Addendum 1, Sample 10).
Further south along the same ridge the limestone is fine grained, slightly siliceous and magnesian. A sample taken 300 metres south of the previous sample yielded 49.76 per cent CaO, 4.69 per cent MgO and 2.78 per cent SiO2 (Sample 11).
B.C. Hydro sampled the ridge in 1981 during a search for dolomite in the Hat Creek area for use in gas scrubbers in the company's proposed coal-fired electrical generating plant.