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.