sedimentary
Limestone
Calcium Carbonate (CaCO3)
AI-generated identification · may be incorrectHardness of 3 on the Mohs scale, colors range from white to gray and tan, dull to earthy luster, fine-grained texture, and effervesces in 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, fine-grained texture, and effervesces in dilute hydrochloric acid.
Formation & geological history
Formed by the accumulation of organic debris like shells and coral, or chemical precipitation of calcium carbonate in shallow marine environments over millions of years.
Uses & applications
Widely used in construction as crushed stone for road base, as a primary component in manufacturing cement, and in agricultural soil conditioning.
Geological facts
Limestone frequently contains well-preserved fossils and forms dramatic cave systems through dissolution by acidic groundwater.
Field identification & locations
Identify in the field by its characteristic fizz when exposed to acid and its relatively soft, fine-grained appearance. Common worldwide in sedimentary basins.
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Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
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Shale
Fissile Sedimentary Rock
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