Rock Identifier
Fossil-bearing limestone pebble (Bioclastic limestone with a probable embedded fossil shell; mainly calcite (CaCO₃)) — fossil
fossil

Fossil-bearing limestone pebble

Bioclastic limestone with a probable embedded fossil shell; mainly calcite (CaCO₃)

AI-generated identification · may be incorrect

Gray, rounded, and dull to slightly granular, with a pale shell-like inclusion. Limestone is typically Mohs 3 and calcite is trigonal; the small specimen’s exact composition and fossil identity cannot be confirmed from the image.

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Physical properties

Gray, rounded, and dull to slightly granular, with a pale shell-like inclusion. Limestone is typically Mohs 3 and calcite is trigonal; the small specimen’s exact composition and fossil identity cannot be confirmed from the image.

Formation & geological history

Likely formed from accumulated marine carbonate shells and sediment, later lithified and rounded by transport. Its geological age cannot be determined from appearance alone.

Uses & applications

Primarily a collectible or educational specimen; limestone is widely used for cement, aggregate, and building stone.

Geological facts

The central pale feature resembles a shell fossil or shell fragment preserved in carbonate rock.

Field identification & locations

Look for fizzing under dilute acid and identifiable shell structure; common limestone occurs in ancient marine deposits worldwide. The pictured pebble alone is likely worth about $1–$10, depending on confirmed fossil detail.

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