Anthracite

noun

1. A dense, shiny coal that has a high carbon content and little volatile matter and burns with a clean flame.
2. A variety of mineral coal (see coal) containing but little hydrogen, and therefore burning almost without flame.
3. Coal-black: as, the anthracite hawk, Urubitinga anthracina.
4. A hard, compact variety of mineral coal, of high luster, differing from bituminous coal in containing little or no bitumen, in consequence of which it burns with a nearly non luminous flame. The purer specimens consist almost wholly of carbon. Also called glance coal and blind coal.
5. A form of carbonized ancient plants; the hardest and cleanest-burning of all the coals; hard coal.