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A type of hydrogen-rich, sapropelic coal characterized by a dull black, sometimes waxy luster that lights easily and burns with a bright, smoky flame. 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, though it sometimes can be found as individual . It was probably formed in lakes and pools where floating spores, transported by wind and water, accumulated in mud mixed with plant debris. During the 19th century cannel coal was used in the manufacture of illuminating gas and as fireplace coal.