sedimentary

Limestone

Sedimentary rock composed mainly of calcium carbonate (CaCO3)

AI-generated identification · may be incorrect

Hardness is 3 on the Mohs scale. Color ranges from white, gray, yellow to brown. Luster is earthy to sub-vitreous. It has a fine-grained texture and reacts with dilute hydrochloric acid.

Identified October 23, 2026More sedimentary →

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Physical properties

Hardness is 3 on the Mohs scale. Color ranges from white, gray, yellow to brown. Luster is earthy to sub-vitreous. It has a fine-grained texture and reacts with dilute hydrochloric acid.

Formation & geological history

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

Uses & applications

Widely used in the manufacturing of cement, as a building material, in road construction, and as a soil conditioner in agriculture.

Geological facts

Limestone often contains well-preserved fossils of ancient marine life. Famous structures like the Great Pyramid of Giza were partially constructed using limestone blocks.

Field identification & locations

Identified in the field by its pale color and characteristic fizz when exposed to weak acid. Found worldwide in regions with ancient marine depositional histories.