Anthracite of anthracite coal consumed in the United States averages 25 million Btu/ton (29 MJ/kg), on the as-received basis (i.e., containing both inherent moisture and mineral matter). Since the 1980s, anthracite refuse or mine waste has been used for coal power generation in a form of recycling. The practice known as reclamation is being applied to culm piles antedating laws requiring mine owners to restore lands to their approximate original condition. Chemically, anthracite may be considered as a transition stage between ordinary bituminous coal and graphite, produced by the more or less complete elimination of the volatile constituents of the former,
Anthracite times been futile, and several such combustion areas exist today. The existence of an underground combustion site can sometimes be identified in the winter where fallen snow is seen to be melted by the warmth conducted from below. Proposals for harnessing this heat as geothermal energy have not been successful. A vein of anthracite that caught fire in Centralia, Pennsylvania in 1962 has been burning ever since, turning the once-thriving borough into a ghost town. Among current producers, Russia, China and Ukraine have the largest estimated recoverable reserves of anthracite. Other countries with substantial reserves include Vietnam and North Korea.