dull coal

dull coal

[¦dəl ¦kōl]
(geology)
A component of banded coal with a grayish color and dull appearance, consisting of small anthraxylon constituents in addition to cuticles and barklike constituents embedded in the attritus.
References in periodicals archive ?
The specimen from Axel Heiberg Island is also strikingly similar to samples of artifacts and naturally occurring dull coal bands on Kodiak Island and the Alaskan Peninsula (Kalkreuth, unpubl.
(Dull coal with a grayish tinge contains clay.) Don't buy chunks of "Cannel coal" for a stove; this high-paraffin coal lights with a match and is meant for open-grate fires.