sedimentary
Coal (Bituminous)
Organic sedimentary rock primarily consisting of carbon (C)
Hardness: 0.5-2.5 on Mohs scale; Color: Black or dark brown; Luster: Dull to sub-metallic; Crystal structure: Amorphous (non-crystalline); Cleavage: Cubic or blocky fracture; Specific gravity: 1.1-1.4
- Hardness
- 0
- Color
- Black or dark brown
- Luster
- Dull to sub-metallic
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Physical properties
Hardness: 0.5-2.5 on Mohs scale; Color: Black or dark brown; Luster: Dull to sub-metallic; Crystal structure: Amorphous (non-crystalline); Cleavage: Cubic or blocky fracture; Specific gravity: 1.1-1.4
Formation & geological history
Formed through the lithification and carbonization of ancient swamp vegetation (peat) under high pressure and heat over millions of years, typically Carboniferous or Cretaceous periods.
Uses & applications
Primarily used as a fuel for electricity generation and industrial heating, and as a raw material for coke production in steel manufacturing.
Geological facts
Bituminous coal is the most abundant type of coal; it contains about 45-86% carbon and is known for producing high heat energy when burned.
Field identification & locations
Identify by its black color, tendency to leave a black soot/smudge on fingers, and relatively lightweight feel. Found in massive underground layers or outcrops in coal-bearing basins.
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