Anthracite Coal

Hardness: 2.5–3 on Mohs scale; Color: Black or dark gray; Luster: Submetallic, vitreous (glassy); Crystal Structure: Amorphous (non-crystalline); Cleavage: Conchoidal fracture; Specific Gravity: 1.3–1.8

Formed through the regional metamorphism of bituminous coal in sedimentary basins. This process requires intense pressure and heat, typically occurring over hundreds of millions of years, often associated with mountain-building events (orogenies). It is most commonly found in Carboniferous aged strata.

Primary use is for domestic and industrial heating because it burns cleanly with high heat output. It is also used in water filtration systems and as a pigment in some industrial processes. High-quality specimens are occasionally used for ornamental carvings or jewelry.

Anthracite is the highest rank of coal, containing 86%–97% carbon. Unlike other coals, it burns with a short blue flame and produces very little smoke or soot. The largest deposits are found in the Appalachian region of Pennsylvania.

Identify in the field by its high luster (shininess), semi-metallic appearance, and the fact that it is relatively light for its size but harder than other types of coal. It will not leave much soot on your hands compared to bituminous coal. Commonly found in folded mountain belts like the Appalachians, Wales, or the Ural Mountains.