Gabriola Island brick
So what are bricks made of. Easy, I thought, clay. Ha. Not exactly. Gabriola Brick and Shale Products that operated from 1910 - 1954, used Gabriola Island blue and brown shale. While fireclay, a glacial clay that produces a much harder brick, was found in conjunction with coal seams near Victoria and Comox on Vancouver Island, Gabriola brick used shale, crushed by millstones made from local sandstone, plus diatomaceous earth and sand. There are perfectly round basins on Gabriola, clearly where the millstones were drilled out. I leave that purposely vague because I don't know how they could do that.
Cretaceous shales of ceramic value are from the Pleistocene era, are sedimentary, have a low fusion temperature and a short vitrification range. All the deposits in British Columbia turn out pink to red building brick. In the nineteenth century, every city had a brickworks, just as they had a lime kiln. Evidently there is either shale, clay shales, or clay throughout the western provinces, but it is only deposits near cities that were developed – it says something about the cost of transportation in the early to mid-twentieth century: punitive relative to the cost of developing a local brickyard. China and stoneware clay, rare in BC, were the basis of the large pottery industry in Medicine Hat, Alberta, which, unlike local brick production, was given a national reach facilitated by the Canadian Pacific Railway.
It seems obvious to say it, but the colour of local brick gives a specific and often unique colour to a city that derives directly from the kind of shale or shale clay the city sits upon. Today, in Canada, all brick comes from one source of brick manufacture in Ontario. Even I-X-L of Medicine Hat, the once dominant brick manufacturer in Western Canada, is gone. According to the 1952 BC Department of Mines bulletin (No. 30): Clay and Shale Deposits of British Columbia, clay and shale are everywhere in abundance – it is impossible that it is mined it out. There must be some other economic equation in operation that makes one vast centralised brickyard with extreme delivery costs more efficient than a local industry. Personally I don't get it.