fossil

Fossil or modern bivalve shell

Calcium carbonate shell, likely aragonite (CaCO₃); exact species cannot be determined from the image

AI-generated identification · may be incorrect

Small, fan-shaped shell with strong radial ribs and cream-to-orange coloring. Shell minerals are typically Mohs 3–4, with a pearly to matte luster; the original animal’s shell is not a crystal specimen.

Identified September 26, 2026More fossil →

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Physical properties

Formation & geological history

Made by a marine bivalve; shells form by biological deposition of calcium carbonate. The image does not establish whether this specimen is modern or fossilized, and no age can be assigned.

Uses & applications

Usually kept as a natural-history collectible or used in crafts and coastal décor; not typically an industrial material.

Geological facts

Bivalve shells commonly preserve radial ribs that strengthen the shell and can help distinguish species.

Field identification & locations

Identify it by its paired-valve form and regularly spaced ribs; similar shells occur on beaches and in marine sediments worldwide. Confirming species or fossil status requires more details, including the other valve and locality.