[1] The 'Brora Main' is a 1m to 1.5m thick seam which has been mined in the Brora area.
It is unusual amongst British coalfields in being of Jurassic age rather than Carboniferous.
The first seams to be worked were those exposed along the North Sea coast though inland mining began in the early nineteenth century.
Mining continued until the 1970s; its principal market being the nearby brickworks.
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