sedimentary

Anthracite Coal

Anthracite (Carbon ≥ 86%)

Hardness: 2.5-3.0; Color: Black or deep charcoal; Luster: Sub-metallic to vitreous (glassy); Structure: Amorphous; Fracture: Conchoidal; Specific Gravity: 1.3-1.7

Hardness: 2
Color: Black or deep charcoal
Luster: Sub-metallic to vitreous (glassy)

Identified June 17, 2026More sedimentary →

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Physical properties

Hardness: 2.5-3.0; Color: Black or deep charcoal; Luster: Sub-metallic to vitreous (glassy); Structure: Amorphous; Fracture: Conchoidal; Specific Gravity: 1.3-1.7

Formation & geological history

Formed through the high-pressure and high-temperature metamorphism of peat and lower-grade coal during tectonic events, typically dating from the Carboniferous Period (300-360 million years ago).

Uses & applications

Primarily used for heating and industrial power generation due to high energy density and low smoke; also used in water filtration systems and historically as a precursor for synthetic graphite.

Geological facts

Anthracite is the highest grade of coal, containing the least amount of impurities and the highest carbon content. It is often referred to as 'hard coal' or 'black diamond'.

Field identification & locations

Identified in the field by its high luster compared to other coals, lack of sooty residue when touched, and its weight (denser than lignite or bituminous coal). Common in Pennsylvania, USA, and parts of China and Russia.