fossil

Clam shell (likely a bivalve shell)

Bivalvia; shell composed primarily of calcium carbonate (usually aragonite and/or calcite)

AI-generated identification · may be incorrect

White, smooth, curved shell with concentric growth lines; hardness roughly 3–4 Mohs. This is biological shell material, not a rock or mineral crystal; species cannot be determined from the image.

Identified October 3, 2026More fossil →

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Physical properties

White, smooth, curved shell with concentric growth lines; hardness roughly 3–4 Mohs. This is biological shell material, not a rock or mineral crystal; species cannot be determined from the image.

Formation & geological history

Formed by a marine or freshwater mollusk during its life, with carbonate deposited in successive layers. It may be recent or fossilized; the image does not establish its age or setting.

Uses & applications

Shells are collected and used for decoration, craft materials, and occasionally jewelry; crushed shell is used in some agricultural and industrial applications.

Geological facts

Bivalve shells consist of two hinged valves, though only one is visible here. Their growth lines can record changes in growth conditions.

Field identification & locations

Identify by its paired-valve form, curved profile, and layered growth lines; shells occur on shorelines and in sedimentary deposits worldwide. No species-level identification is reliable from this view.