sedimentary

Anthracite Coal

Anthracite

Hardness: 2.5-3.0; Color: Black to dark grey; Luster: Submetallic, vitreous (shiny); Structure: Amorphous (lacks crystal structure); Specific Gravity: 1.3-1.8; Fracture: Conchoidal.

Hardness: 2
Color: Black to dark grey
Luster: Submetallic, vitreous (shiny)

Identified May 23, 2026More sedimentary →

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Physical properties

Hardness: 2.5-3.0; Color: Black to dark grey; Luster: Submetallic, vitreous (shiny); Structure: Amorphous (lacks crystal structure); Specific Gravity: 1.3-1.8; Fracture: Conchoidal.

Formation & geological history

Formed from the burial and heating of organic plant matter over millions of years (Carboniferous era). It undergoes low-grade metamorphism from bituminous coal, losing most volatile matter.

Uses & applications

Primarily used for heating and industrial energy due to high carbon content and low smoke. Occasionally used in sculpture, jewelry (jet is a similar form), or for filtration media.

Geological facts

Anthracite contains the highest carbon content of all coals (86%-97%). It is often referred to as 'hard coal' and burns with a short, blue, smokeless flame.

Field identification & locations

Identify by its light weight compared to stone, shiny black appearance, and lack of soot on hands. Commonly found in Pennsylvania, USA, South Wales, and parts of China.