sedimentary
Coal
Bituminous Coal
AI-generated identification · may be incorrectHardness 1.5 to 2.5 on the Mohs scale, black to dark brown color, submetallic to dull luster, amorphous crystal structure, specific gravity 1.1 to 1.4.
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Physical properties
Hardness 1.5 to 2.5 on the Mohs scale, black to dark brown color, submetallic to dull luster, amorphous crystal structure, specific gravity 1.1 to 1.4.
Formation & geological history
Formed from the accumulation and compaction of ancient plant debris in swampy environments over millions of years during the Carboniferous period and later.
Uses & applications
Primarily used for electricity generation, steel production, and industrial heating.
Geological facts
Coal represents ancient solar energy captured by plants hundreds of millions of years ago. It is a combustible sedimentary rock primarily composed of carbon, hydrogen, and oxygen.
Field identification & locations
Easily identified by its lightweight nature, black streak, and dirty residue left on hands. Commonly found in sedimentary basins worldwide.
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