sedimentary
Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
Hardness: 2.5-3; Color: Jet black to dark gray with a metallic luster; Structure: Amorphous (non-crystalline); Conchoidal fracture; Specific gravity: 1.3-1.4.
- Hardness
- 2
- Color
- Jet black to dark gray with a metallic luster
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Physical properties
Hardness: 2.5-3; Color: Jet black to dark gray with a metallic luster; Structure: Amorphous (non-crystalline); Conchoidal fracture; Specific gravity: 1.3-1.4.
Formation & geological history
Formed through the intense metamorphism of peat and bituminous coal under high pressure and temperature over millions of years, primarily during the Carboniferous period.
Uses & applications
Primarily used as a high-grade fuel for domestic heating and industrial power generation; also used in water filtration systems and as a pigment in some plastics.
Geological facts
Anthracite has the highest carbon content (86% to 98%) of all coal types and contains the lowest amount of impurities. It burns with a clean, blue flame and produces very little smoke.
Field identification & locations
Identifiable by its high luster, lack of soot when handled compared to bituminous coal, and its tendency to break with smooth, curved surfaces (conchoidal fracture). Major deposits are found in Pennsylvania, USA, and parts of China and Russia.
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