sedimentary
Coal
Bituminous Coal / Anthracite
Hardness ranges from 1 to 3 on the Mohs scale, color is typically black to dark brown, luster can be dull to vitreous or submetallic, amorphous crystal structure with no cleavage, and a relatively low specific gravity (1.1 to 1.5).
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Physical properties
Hardness ranges from 1 to 3 on the Mohs scale, color is typically black to dark brown, luster can be dull to vitreous or submetallic, amorphous crystal structure with no cleavage, and a relatively low specific gravity (1.1 to 1.5).
Formation & geological history
Formed from the accumulation, burial, and compaction of ancient plant debris (peat) in swampy wetlands over millions of years, primarily during the Carboniferous period.
Uses & applications
Primarily used as a combustible fossil fuel for electricity generation, steel production, and industrial manufacturing.
Geological facts
Coal is often called 'buried sunshine' because the energy it stores originally came from the sun via ancient photosynthesis.
Field identification & locations
Identified by its lightweight nature, black streak, and tendency to soil the hands or leave a dark mark. Found in sedimentary coal basins worldwide.
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