coal ball

coal ball

[′kōl ‚bȯl]
(geology)
A subspherical mass containing mineral matter embedded with plant material, found in coal seams and overlying beds of the late Paleozoic.
References in periodicals archive ?
Coal balls in batter and fry until golden brown Drain on paper towels, then transfer lo large bowl with curry sauce.
The first discovery of in situ coal balls in Nova Scotia.
By the nature of inherent limited size, coal balls cannot preserve the large parts of the fronds known to be borne by the arborescent alethopterid plant.