sedimentary

Coal (Anthracite)

Anthracite Coal (C)

AI-generated identification · may be incorrect

Hardness: 2.5-3.0 Mohs; Color: Iron-black to dark grey; Luster: Submetallic to vitreous; Crystal Structure: Amorphous; Cleavage: Conchoidal fracture; Specific Gravity: 1.3–1.7

Hardness: 2
Color: Iron-black to dark grey
Luster: Submetallic to vitreous

Identified April 11, 2026More sedimentary →

Explore Coal (Anthracite) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 2.5-3.0 Mohs; Color: Iron-black to dark grey; Luster: Submetallic to vitreous; Crystal Structure: Amorphous; Cleavage: Conchoidal fracture; Specific Gravity: 1.3–1.7

Formation & geological history

Formed through the metamorphism of peat and bituminous coal over millions of years under high pressure and temperature, often carboniferous in age (300-360 million years).

Uses & applications

Used primarily for heating, fuel for power generation, and carbon filtering. It was historically used in water filtration and as a pigment.

Geological facts

Anthracite is the highest rank of coal, containing 86%–97% carbon. Unlike other coals, it burns with a clean blue flame and produces very little smoke or soot.

Field identification & locations

Identify by its dark color, relative lightness (density), and lack of dirtiness compared to softer coals. Often found in folded mountain belts like the Appalachians.