sedimentary

Anthracite Coal

Anthracite (Highly Metamorphosed Coal)

AI-generated identification · may be incorrect

Hardness: 2.5-3.0; Color: Black or dark brownish-black; Luster: Submetallic to vitreous (glassy); Structure: Amorphous/Non-crystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 1.3-1.8

Hardness: 2
Color: Black or dark brownish-black
Luster: Submetallic to vitreous (glassy)

Identified July 14, 2026More sedimentary →

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Physical properties

Hardness: 2.5-3.0; Color: Black or dark brownish-black; Luster: Submetallic to vitreous (glassy); Structure: Amorphous/Non-crystalline; Cleavage: None (conchoidal fracture); Specific Gravity: 1.3-1.8

Formation & geological history

Formed through the burial and intense pressure/heat of peat and organic plant matter over millions of years, typically during the Carboniferous period. It is the highest grade of coal, having undergone low-grade metamorphism.

Uses & applications

Primarily used as a residential and industrial fuel due to its high carbon content and low impurity levels. Also used in water filtration and as a pigment or for carving decorative items.

Geological facts

Anthracite contains the highest percentage of fixed carbon (86% to 97%) of all coal types and burns with a clean blue flame, producing very little smoke.

Field identification & locations

Identify by its glassy, jet-black appearance and the fact that it does not soil fingers when touched (unlike bituminous coal). Commonly found in the Appalachian mountains of Pennsylvania, USA.