sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectHardness of 3 on the Mohs scale, typically gray, white, or tan in color, with a dull to subvitreous luster and fine-grained crystal structure.
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Physical properties
Hardness of 3 on the Mohs scale, typically gray, white, or tan in color, with a dull to subvitreous luster and fine-grained crystal structure.
Formation & geological history
Formed through the accumulation of shell, coral, algal, and fecal debris, or via chemical precipitation of calcium carbonate in marine environments over millions of years.
Uses & applications
Widely used in construction as building stone, as an aggregate for road bases, in the manufacture of cement, and in agricultural soil treatment.
Geological facts
Limestone frequently contains well-preserved fossils of ancient marine organisms and dissolves easily in weakly acidic groundwater to form extensive cave systems.
Field identification & locations
Identified easily by its characteristic fizz when exposed to dilute hydrochloric acid; found globally in regions with past shallow marine coverage.
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fossil
Sandstone or Siltstone
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