Raw anthracite
Raw anthracite is one of the highest-ranking coals in terms of carbon content and energy density. It has been valued for centuries for its distinctive physical and chemical properties, and…
Raw sub-bituminous coal
This article examines raw sub-bituminous coal: its nature, where it occurs, how and where it is mined, its economic and industrial roles, and environmental and policy considerations. Sub-bituminous coal occupies…
Nut coal
Nut coal is a widely recognized commercial grade of coal, principally defined by its particle size and practical applications rather than by a single chemical composition. It occupies a middle…
Coal with high liptinite content
This article examines coals that are unusually rich in liptinite macerals — a group of organic constituents in coal that derive from spores, cuticles, resins and algal materials. Such coals…
