sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectMohs hardness of 3; white, gray, or buff color; dull to earthy luster; fine-grained crystal structure with no visible cleavage.
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Physical properties
Mohs hardness of 3; white, gray, or buff color; dull to earthy luster; fine-grained crystal structure with no visible cleavage.
Formation & geological history
Formed through the accumulation and compaction of organic remains like shells and coral, or chemical precipitation in marine environments.
Uses & applications
Widely used in construction, cement production, agriculture for soil conditioning, and as a flux in steel manufacturing.
Geological facts
Limestone often preserves abundant fossils and is famous for forming spectacular cave systems through dissolution by acidic groundwater.
Field identification & locations
Identified easily by its characteristic fizz when tested with dilute hydrochloric acid. Commonly found in sedimentary basins and ancient sea beds worldwide.
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