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, colors range from white to gray and tan, dull to earthy luster, and exhibits effervescence when exposed to dilute hydrochloric acid.

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Physical properties

Hardness of 3 on the Mohs scale, colors range from white to gray and tan, dull to earthy luster, and exhibits effervescence when exposed to dilute hydrochloric acid.

Formation & geological history

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

Uses & applications

Extensively used in construction as building stone, as an aggregate for road bases, and in the manufacturing of cement and lime.

Geological facts

Limestone frequently contains well-preserved fossils and forms dramatic landscapes characterized by caves, sinkholes, and karst topography.

Field identification & locations

Identify in the field by its characteristic reaction to acid and relatively soft texture; common globally in sedimentary basins and ancient sea beds.