Rock Identifier
Limestone (Calcium Carbonate (CaCO3)) — sedimentary
sedimentary

Limestone

Calcium Carbonate (CaCO3)

AI-generated identification · may be incorrect

Hardness of 3 on the Mohs scale, typically white, gray, or tan in color, with a dull to earthy luster and fine-grained crystal structure.

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Physical properties

Hardness of 3 on the Mohs scale, typically white, gray, or tan in color, with a dull to earthy luster and fine-grained crystal structure.

Formation & geological history

Formed from the accumulation of skeletal fragments of marine organisms or chemical precipitation in shallow marine environments over millions of years.

Uses & applications

Widely used in construction, cement production, agriculture for soil neutralization, and as a dimension stone.

Geological facts

Limestone often contains well-preserved fossils and dissolves slowly in acidic water, creating dramatic cave systems and karst topography.

Field identification & locations

Easily identified by its characteristic fizz when tested with dilute hydrochloric acid; found globally in sedimentary basins.