sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectHardness of 3 on the Mohs scale, typically gray or white with a dull to earthy luster. Composed mainly of calcite or aragonite with fine-grained crystal structure.
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Physical properties
Hardness of 3 on the Mohs scale, typically gray or white with a dull to earthy luster. Composed mainly of calcite or aragonite with fine-grained crystal structure.
Formation & geological history
Formed through the accumulation of organic remains like shell and coral debris, or chemical precipitation in marine environments over millions of years.
Uses & applications
Widely used in construction as building stone, aggregate in concrete, and manufacturing cement, lime, and steel.
Geological facts
Limestone frequently contains well-preserved fossils and forms striking karst topographies like caves and sinkholes.
Field identification & locations
Easily identified by its characteristic fizz when tested with dilute hydrochloric acid. Found globally in sedimentary basins and ancient sea beds.
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Fossiliferous Sedimentary Rock
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