The Bamberton limestone quarry is located on the west shore of Saanich Inlet, 23 kilometres northwest of Victoria.

The region is underlain by the Mesozoic and/or Paleozoic Wark Gneiss and volcanics of the Lower Jurassic Bonanza Group. The deposit is part of a discontinuous carbonate horizon that extends from Cordova Bay northwestward across Saanich Inlet to the east shore of Shawnigan Lake. Its general fine-grained, massive character and its association with greenstones and magnetite-sulphide skarns suggests that this horizon is correlative with the Upper Triassic Quatsino Formation, Vancouver Group.

The deposit is comprised of several limestone lenses. The main lens extends northwest from the shore of Saanich Inlet for 700 metres and is up to 150 metres thick. Bedding within the lens strikes 120 degrees and dips 60 to 90 degrees northwest. The lens is intercalated with tabular greenstone bodies, of similar orientation, that vary from less than a metre to 15 metres in thickness. These are basaltic in composition and likely represent flows. Faults, generally trending northwest and dipping steeply northeast, are exposed in the quarries.

The limestone of the main lens is generally dark bluish grey and fine grained. Several thin sections reveal small irregular quartz grains, detrital calcite fragments and spherical radiolaria and foraminifera in a very fine, limy mud cement containing rare patches of carbonaceous matter. The main lens mainly consists of calcium to high calcium limestone. Bands and irregular masses of magnesian limestone of similar appearance to the high calcium limestone become apparent to the northeast. One 6-metre thick band of magnesian limestone contains 17 to 40 percent magnesium carbonate (CANMET Report 811, page 132). Five chip samples taken in April 1946 in succession across the face of the lower main quarry averaged 53.88 per cent CaO, 0.86 per cent MgO, 1.92 per cent insolubles, 0.166 per cent R2O3, 0.359 per cent Fe2O3, 0.019 per cent MnO, 0.023 per cent P2O5, 0.051 per cent sulphur and 42.78 per cent ignition loss (Bulletin 23, page 95, Samples 4, and 6 to 9).

In 1950, diamond drilling in a drift-covered area northwest of the main lens encountered a second limestone body. This body trends northwest, dips steeply, is 300 metres long and at least 30 metres wide. The lens, hosted in greenstone, contains irregular greenstone masses.

The quarries were in operation between 1913 and 1957 while the adjacent cement plant remained in production up to 1980. Between 1913 and 1957, 3.7 million tonnes of limestone were quarried. The limestone was produced from two quarries in the main lens, the upper main and lower main quarries and from a single quarry in the second lens to the northwest.

A.R.M. Industries quarried 21,000 tonnes of limestone for riprap in 1988.