sedimentary

White limestone

Calcite-dominated carbonate rock (CaCO₃), possibly chalky limestone

AI-generated identification · may be incorrect

Typically Mohs hardness 3, white to cream color, dull to earthy luster, fine-grained or microcrystalline texture, and irregular fracture. Calcite-rich limestone effervesces strongly with dilute hydrochloric acid or vinegar, though surface weathering may reduce the reaction.

Identified September 6, 2026More sedimentary →

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Physical properties

Formation & geological history

Forms from accumulated marine carbonate mud, shells, or reef material that lithifies into calcite rock, commonly during Paleozoic–Cenozoic marine sedimentation. The specimen appears weathered and may have been cut or broken from construction stone.

Uses & applications

Used for cement and lime production, aggregate, building stone, soil treatment, and monuments; attractive varieties are polished for interiors. This rough piece has little jewelry value.

Geological facts

The image shows a porous, powdery white specimen with possible iron-oxide staining, consistent with limestone rather than a crystalline marble. It cannot be identified to a precise formation or age from the photograph alone.

Field identification & locations

Look for visible bedding or fossils, low hardness, and acid fizz; marble is harder, crystalline, and more sugary-looking. Common worldwide, especially in former shallow-marine basins.