A bed of Lower Permian aged limestone outcrops discontinuously on both sides of the Zymoetz River between 10 and 18 kilometres east of Terrace. The bed is faulted up into a series of west to northwest trending thrust sheets up to 5 kilometres long between Permian aged greenstone, tuff and breccia and Upper Triassic to Lower Jurassic aged basaltic to rhyolitic flows, tuff and breccia of the Telkwa Formation. Bedding just northeast of the Zymoetz River strikes 123 degrees and dips 30 degrees northeast.

This carbonate unit is composed of white to pale green, medium to fine grained limestone underlain by argillaceous limestone and overlain by impure, fusilinid bearing, rose coloured limestone. The limestone is locally silicious. A few andesitic dykes intrude the deposit. A sample taken across 30 metres of limestone exposed in a roadcut on the south side of the Zymoetz River contained 49.73% CaO, 0.70% MgO, 9.28% insolubles, 0.60% R2O3, 0.70% Fe2O3, 0.019% MnO, 0.019% P2O5, 0.004% sulphur and 39.44% ignition loss (Annual Report 1962, p. 153).