sedimentary
Coal
Bituminous Coal / Anthracite
AI-generated identification · may be incorrectMohs hardness of 1.5 to 2.5, black color, submetallic to dull luster, amorphous crystal structure, and a black streak.
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Physical properties
Mohs hardness of 1.5 to 2.5, black color, submetallic to dull luster, amorphous crystal structure, and a black streak.
Formation & geological history
Formed from compressed plant debris in ancient swamps and wetlands over hundreds of millions of years during the Carboniferous period.
Uses & applications
Primarily used for electricity generation, steel production, and historical heating.
Geological facts
Coal is often called bottled sunshine because it stores solar energy captured by ancient plants hundreds of millions of years ago.
Field identification & locations
Identified by its extremely light weight, black color, and tendency to leave a dark smudge on skin or paper. Found globally in sedimentary coal basins.
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