A mass of limestone of the Mississippian to Triassic Cache Creek Group forms a 150 metre high ridge extending southeastward for 1.25 kilometres along the north side of the Necoslie River road, 10 kilo- metres southeast of Fort St. James. The deposit lies along the southwest margin of a belt of limestone with minor chert, argillite and greenstone (andesite) up to 10 kilometers wide that extends northwestward from Gordon Lake for 200 kilometres.
The limestone is mostly light grey, medium to fine grained and well fractured. Irregular masses of chert 2 to 15 centimetres thick and up to 30 centimetres long are fairly common. An irregular breccia zone is exposed in the quarry.
A sample composed of chips taken at 0.6 metre intervals across the 15 metre wide quarry face contained 54.82% CaO, 0.24% MgO, 0.75% insolubles, 0.19% R2O3, 0.10% Fe2O3, 0.03% MnO, 0.05% P2O5, 0.003% sulphur and 43.38% ignition loss (Geology, Exploration and Mining in B.C. 1969, p. 392).
A small amount of limestone was produced from a quarry on the northwest end of the ridge a hundred metres off the road sometime previous to 1969.