sedimentary

Anthracite Coal

Anthracite

Mohs Hardness: 2.5-3; Color: Jet black to dark grey; Luster: Sub-metallic to brilliant/glassy; Structure: Amorphous; Fracture: Conchoidal; Specific Gravity: 1.3-1.8

Hardness: 2
Color: Jet black to dark grey
Luster: Sub-metallic to brilliant/glassy

Identified July 19, 2026More sedimentary →

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Physical properties

Mohs Hardness: 2.5-3; Color: Jet black to dark grey; Luster: Sub-metallic to brilliant/glassy; Structure: Amorphous; Fracture: Conchoidal; Specific Gravity: 1.3-1.8

Formation & geological history

Formed through the geological process of coalification where plant matter is subjected to high pressure and temperature over millions of years. It is the highest grade of coal, representing the final stage of the metamorphic transformation of sedimentary peat.

Uses & applications

Historically used for high-grade heating and industrial fuel due to its high carbon content and low impurities; also used for water filtration and as a decorative stone/carving material.

Geological facts

Anthracite contains the highest carbon count (86-98%) and the fewest impurities of all coal types. It burns with a short blue flame and emits very little smoke. It is often referred to as 'hard coal'.

Field identification & locations

Identify by its characteristic shiny, glass-like luster and black color that does not soil the fingers like softer coals (bituminous). Found predominantly in the Appalachian Mountains of Pennsylvania, USA, as well as parts of South Wales and China.