Building stone and riprap was once quarried by the Canadian Pacific Railway Company at Granite, 5 kilometres west of Nelson.
The quarry is developed in granodiorite of the Middle to Late Jurassic Nelson Intrusions on the southeastern margin of the Nelson batholith. Between Nelson and the Kootenay River bridge, west of Nelson, the stone is grey, coarse grained and gneissic in some exposures and shattered in others.
The stone is cut by two sets of joints at the quarry, one set strikes 060 degrees and dips vertically and the second set strikes 145 degrees and dips 85 degrees southwest. A dome like sheeting, spaced 2.4 to 3 metres apart, dips north in the middle of the quarry, northwest at the west end of the quarry and northeast at the east end. The middle of the quarry is less jointed, enabling larger blocks to be removed.
The granodiorite is fairly uniform in grain and colour throughout and contains black knots and light coloured veinlets. The stone is distinguished by its large feldspar crystals and black mica, distributed in a feathery manner. A sample analyzed as follows (CANMET Report 452, page 109, sample 1523):
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MAJOR OXIDES PHYSICAL PROPERTIES
SiO2 66.46 Specific gravity 2.705
Al2O3 15.34 Crushing strength (dry) (lbs/sq.in.) 35,512
Fe2O3 1.68 Transverse strength (lbs/sq.in.) 2,543
Fe3O4 1.83 Shearing strength (lbs/sq.in.) 1,418
CaO 3.43
MgO 1.11
Na2O 4.86
K2O 4.58
TiO2 0.27
H2O 0.29
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A considerable amount of stone was quarried by Canadian Pacific Railway in the early 1900's, up to about 1915. The resulting quarry measured 260 metres in length with a face up to 30 metres high, trending 070 degrees. The granodiorite was used for culverts and bridge piers along the railway line and a minor amount was also used for building purposes in Nelson. No production figures are available.
