sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectHardness of 3 on Mohs scale, colors range from white to gray and tan, dull to earthy luster, amorphous or fine-grained crystal structure, exhibits good cleavage in three directions.
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Physical properties
Hardness of 3 on Mohs scale, colors range from white to gray and tan, dull to earthy luster, amorphous or fine-grained crystal structure, exhibits good cleavage in three directions.
Formation & geological history
Formed through the accumulation of skeletal fragments of marine organisms or chemical precipitation of calcium carbonate in shallow marine environments over millions of years.
Uses & applications
Widely used in construction as building stone, a primary component in cement manufacture, agricultural soil conditioning, and metallurgical flux.
Geological facts
Limestone frequently contains well-preserved fossils of ancient marine life and is susceptible to dissolution by acidic water, creating spectacular cave systems and karst topography.
Field identification & locations
Easily identified by its characteristic fizz when tested with dilute hydrochloric acid. It is globally abundant and found extensively in sedimentary basins.
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