sedimentary

Coal (Bituminous)

Bituminous Coal (C)

Hardness: 0.5-2.5 on Mohs scale; Color: Black to dark brown; Luster: Dull to sub-vitreous; Crystal Structure: Amorphous; Cleavage: None/Conchoidal or Blocky fracture; Density: 1.1-1.5 g/cm3

Hardness: 0
Color: Black to dark brown
Luster: Dull to sub-vitreous

Identified June 25, 2026More sedimentary →

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Physical properties

Hardness: 0.5-2.5 on Mohs scale; Color: Black to dark brown; Luster: Dull to sub-vitreous; Crystal Structure: Amorphous; Cleavage: None/Conchoidal or Blocky fracture; Density: 1.1-1.5 g/cm3

Formation & geological history

Formed from the burial and compaction of plant matter in swamps and wetlands over millions of years (Carboniferous era). It undergoes low-grade metamorphism from peat to lignite and then to bituminous coal.

Uses & applications

Primarily used as a fossil fuel for electricity generation, industrial heat, and as a feedstock for producing coke in steel manufacturing. Small pieces are occasionally used in jewelry or jet-like ornaments.

Geological facts

Bituminous coal is the most abundant type of coal. It is often referred to as 'soft coal,' though it is harder than lignite. It is a major source of greenhouse gas emissions when burned.

Field identification & locations

Identified in the field by its black color, tendency to leave black residue on hands, and blocky fracture patterns. Commonly found in massive sedimentary basins in regions like the Appalachians, UK, and China.