fossil

Fossilized bivalve shell (small cockle-type shell)

Bivalvia; exact species cannot be determined from the image

AI-generated identification · may be incorrect

Small, fan-shaped shell with prominent radial ribs and cream-to-tan color. The shell material is chiefly calcium carbonate (usually aragonite or calcite); Mohs hardness is about 3–4, with a dull to pearly luster. Crystal structure and cleavage are not reliably identifiable from the photo.

Identified September 26, 2026More fossil →

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Physical properties

Formation & geological history

Bivalves formed shells in marine environments; fossilization can preserve or replace shell material in sediment. The image does not establish whether this specimen is fossilized or its geological age.

Uses & applications

Primarily a collecting or decorative specimen; shell-derived calcium carbonate has broader uses in lime and agricultural products.

Geological facts

Radial ribs strengthen shells and can help distinguish bivalve groups, but identifying a species requires details such as hinge, interior, and locality.

Field identification & locations

Look for paired valves, a hinge line, and ribbed growth patterns; similar shells occur on beaches and in marine sediments worldwide. The photo alone cannot confirm fossil status.