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)
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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.
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