sedimentary

Anthracite Coal

Carbon (with trace impurities)

Hardness: 2.7-3.0 Mohs. Color: Jet black to dark steel-gray, often with iridescent tarnish. Luster: Submetallic to vitreous. Structure: Amorphous. Fracture: Conchoidal. Specific Gravity: 1.3-1.4.

Hardness: 2
Color: Jet black to dark steel-gray, often with iridescent tarnish
Luster: Submetallic to vitreous

Identified July 26, 2026More sedimentary →

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Physical properties

Hardness: 2.7-3.0 Mohs. Color: Jet black to dark steel-gray, often with iridescent tarnish. Luster: Submetallic to vitreous. Structure: Amorphous. Fracture: Conchoidal. Specific Gravity: 1.3-1.4.

Formation & geological history

Formed through intense metamorphism of organic plant material subjected to high pressure and heat over hundreds of millions of years, primarily during the Carboniferous period.

Uses & applications

Used historically as a high-grade smokeless fuel, in steel production, water filtration systems, and as geological or mineral educational specimens.

Geological facts

Anthracite is the highest rank of coal, containing the highest percentage of fixed carbon (up to 98%) and the lowest amount of impurities and volatile matter.

Field identification & locations

Identified by its shiny, glassy appearance, lightweight feel, non-sooty touch compared to lower-grade coal, and conchoidal fracture. Common in eastern Pennsylvania, China, and Russia.