Rock Identifier
Limestone (Calcareous sedimentary rock (CaCO3)) — sedimentary
sedimentary

Limestone

Calcareous sedimentary rock (CaCO3)

AI-generated identification · may be incorrect

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

Formation & geological history

Formed through the accumulation and compaction of organic remains like shells and coral, or chemical precipitation in marine environments over millions of years.

Uses & applications

Widely used in the construction industry for producing cement, road aggregate, and as a dimension building stone.

Geological facts

Limestone frequently contains well-preserved fossils and forms dramatic landscapes known as karst topography with caves and sinkholes.

Field identification & locations

Easily identified by its characteristic fizz when tested with dilute hydrochloric acid due to the presence of calcium carbonate.