Rock Identifier
Fossiliferous limestone pebble (Bioclastic limestone, composed mainly of calcite (CaCO₃); the visible holes may be fossil molds or natural cavities) — fossil
fossil

Fossiliferous limestone pebble

Bioclastic limestone, composed mainly of calcite (CaCO₃); the visible holes may be fossil molds or natural cavities

AI-generated identification · may be incorrect

Pale beige, dull to slightly waxy; calcite hardness about 3 Mohs and rhombohedral crystal structure. The rounded shape and porous openings are consistent with a worn carbonate fragment, though the image cannot confirm their origin.

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Physical properties

Pale beige, dull to slightly waxy; calcite hardness about 3 Mohs and rhombohedral crystal structure. The rounded shape and porous openings are consistent with a worn carbonate fragment, though the image cannot confirm their origin.

Formation & geological history

Likely formed from marine carbonate sediment and shell or skeletal debris, later lithified and rounded by water; its age cannot be determined from the photo.

Uses & applications

Small pieces are mainly collected or used decoratively; limestone is widely used for cement, aggregate, and building stone.

Geological facts

Limestone often preserves marine fossils and dissolves readily in weak acid, sometimes fizzing visibly.

Field identification & locations

Look for carbonate texture and shell-like structures; a dilute acid reaction can help identify calcite-rich limestone. Similar material occurs in sedimentary regions worldwide, but this specimen’s location is unknown.

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