sedimentary

Rounded limestone pebble

Limestone, composed chiefly of calcite (CaCO₃)

AI-generated identification · may be incorrect

Pale gray-beige, dull to slightly earthy luster, with a fine-grained surface and small pits; calcite hardness is 3 Mohs. The rounded shape and visible surface suggest abrasion, though the image alone cannot confirm the exact rock type.

Identified October 3, 2026More sedimentary →

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Physical properties

Formation & geological history

Likely formed from accumulated carbonate sediment or shell material, later compacted and cemented; its age cannot be determined from the image. Rounding probably occurred through water or shoreline abrasion.

Uses & applications

Common limestone is used for cement, aggregate, building stone, and soil treatment; this small pebble has little commercial value but may be kept as a specimen.

Geological facts

Limestone fizzes with dilute hydrochloric acid, a useful field test for calcite-rich material.

Field identification & locations

Its pale color, fine texture, and possible carbonate pits are consistent with limestone, but other pale rocks are possible. Similar pebbles occur in riverbeds and beaches; an acid test can help identify it.