sedimentary

Rounded pebble, likely limestone

Fine-grained calcite-rich carbonate rock (probable limestone; image alone cannot confirm)

AI-generated identification · may be incorrect

Small, rounded, dull beige-gray pebble with a fine, mottled texture and no visible crystals or cleavage. Likely Mohs hardness 3 if limestone; specific gravity about 2.5–2.7.

Identified October 9, 2026More sedimentary →

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Physical properties

Small, rounded, dull beige-gray pebble with a fine, mottled texture and no visible crystals or cleavage. Likely Mohs hardness 3 if limestone; specific gravity about 2.5–2.7.

Formation & geological history

If limestone, it formed from carbonate sediment or biological debris that lithified, then was rounded by transport in water. Its age and exact setting cannot be determined from the image.

Uses & applications

A common type of limestone is used for cement, aggregate, and building stone; this pebble is mainly suitable for collecting or decoration.

Geological facts

A drop of dilute acid fizzes on calcite-rich limestone, though this test can damage the specimen.

Field identification & locations

Its smooth, rounded shape suggests abrasion by water or sediment; inspect a fresh surface and test hardness or acid reaction to distinguish limestone from other pale pebbles. Similar pebbles occur in streambeds and beaches worldwide.