Cannel coal consists of micrinites, macerals of the exinite group, and certain inorganic materials. Cannel coal usually occurs at the top or bottom of other coals. The excess of hydrogen in a coal, above the amount necessary to combine with its oxygen to form water, is known as disposable hydrogen, and is a measure of the fitness of the coal for use in gas-making. This excess is greatest in what is known as cannel coal, the Lancashire kennel or candle coal, so named from the bright light it gives out when burning. This, although of very small value as fuel, commands a specially high price for gas-making. Cannel is more compact and duller than ordinary coal, and can be wrought in the lathe and polished. In the Durham coal-field (and possibly elsewhere) carving cannel coal into ornaments was a popular pastime amongst the miners.
In 1540, an antiquary called John Leland reported that Sir Roger Bradshaigh had discovered a plentiful shallow seam of smooth, hard, Cannel Coal on his estate, near Haigh, Greater Manchester. The deposit came to be known as the Great Haigh fault. The shallow depth of the Cannel meant that it was suitable for the simple surface mining methods available at that time. It could be worked and carved, and was an excellent light fuel which burned with a bright flame, it was easily lit and left virtually no ash. Widely used for domestic lighting in the early 19th Century, before the incandescent gas mantle was available, it gradually lost favour; as the use of coal gas made it obsolete.