sedimentary

Anthracite Coal

Anthracite

Hardness: 2.5–3.0 (Mohs); Color: Black or brownish-black; Luster: Submetallic, vitreous (shiny); Structure: Amorphous; Fracture: Conchoidal; Specific Gravity: 1.3–1.8

Hardness: 2
Color: Black or brownish-black
Luster: Submetallic, vitreous (shiny)

Identified July 19, 2026More sedimentary →

Explore Anthracite Coal 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: Black or brownish-black; Luster: Submetallic, vitreous (shiny); Structure: Amorphous; Fracture: Conchoidal; Specific Gravity: 1.3–1.8

Formation & geological history

Formed from the remains of prehistoric plants in swampy environments that were compressed over millions of years (Carboniferous period) under high heat and pressure, turning peat into lignite, then bituminous coal, and finally anthracite.

Uses & applications

Primarily used as a residential and industrial fuel due to its high energy density and low smoke. Also used in water filtration systems and as a historical source for coal jewelry (jet).

Geological facts

Anthracite is the highest grade of coal, containing the highest percentage of fixed carbon (86% to 97%). It burns with a short, blue, and smokeless flame. It is sometimes known as 'hard coal'.

Field identification & locations

Identify by its lightweight feel compared to common rocks, shiny black luster, and the fact that it does not soil fingers like softer coals. Commonly found in Pennsylvania, USA, and parts of Wales and China.