Granite was quarried along the east side of Highway 3, 2.3 kilometres north of Sirdar.
This area on either side of the south end of Kootenay Lake is underlain by granitic rocks of the Early Cretaceous Bayonne batholith. The quarry is developed at the foot of a ridge of granite, 90 metres high, near the southern margin of the batholith. The quarried stone is a medium grained, light grey granodiorite containing white to opaque feldspar, glossy to translucent quartz and black biotite. Undesirable knots or segregations are reported to be absent. Large blocks can be removed despite the well-defined jointing.
The stone has been quarried more or less continuously since 1913. Up to the early 1950s, the quarry was operated by James S. Wilson and Company Ltd., producing dimension stone for monuments and buildings in Alberta and British Columbia, such as the War Memorial in Creston, British Columbia. The granite was marketed under the trade name "Grey Royal".
The deposit was periodically quarried and mined underground by Kootenay Granite Products Ltd. between 1955 and 1960. The company sold crushed and ground granite for poultry grit, stucco-dash, sand blasting and filler for roofing asphalt. International Marble and Stone Company Ltd. operated the quarry and adjacent processing plant since 1961, when it took over the operation from Kootenay Granite Products. The stone is mined underground and processed on site to produce crushed and ground granite for poultry grit and construction aggregate for architectural, decorative and landscaping purposes (D. Gunning, personal communication, 1991).
Imasco Minerals Ltd. operates the property.