sedimentary

Rounded pale pebble, likely limestone

Micritic limestone, primarily calcite (CaCO₃)

AI-generated identification · may be incorrect

Cream to pale yellow, dull earthy luster, fine-grained and rounded; Mohs hardness about 3, with no visible cleavage. Likely specific gravity is approximately 2.5–2.7; exact identification is limited by the photograph.

Identified August 28, 2026More sedimentary →

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Physical properties

Formation & geological history

Limestone forms from accumulated carbonate mud or biological shells, later compacted and cemented; its age cannot be determined visually. The smooth shape suggests transport by water or prolonged abrasion, or deliberate tumbling.

Uses & applications

Common limestone is used for aggregate, cement, lime, building stone, and soil conditioning; small pieces have modest decorative or educational value.

Geological facts

Calcite-rich limestone effervesces visibly when a drop of dilute hydrochloric acid is applied; household vinegar may produce weaker bubbling. The specimen could also be a pale calcite-rich concrete or another light-colored stone, requiring testing for certainty.

Field identification & locations

Look for bubbling with acid, softness sufficient to scratch with a steel nail, and a powdery white streak; quartz will not bubble and is much harder. Common worldwide in sedimentary basins, river gravels, and beaches.