fossil

Small marine shell fragment

Calcareous shell, primarily calcium carbonate (aragonite or calcite); exact taxon indeterminate

AI-generated identification · may be incorrect

White, opaque, dull to slightly satiny, with curved growth ridges and possible nacreous structure; hardness about 3–4 Mohs, low-to-moderate density, and no obvious cleavage. Its shape is more consistent with a shell fragment than a mineral crystal or lithified rock.

Identified August 15, 2026More fossil →

Explore Small marine shell fragment in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed biologically by a marine mollusk, usually from the Holocene or recent seafloor, beach, or shell deposit; it is not necessarily a fossil unless mineral replacement or burial is demonstrated.

Uses & applications

Typically a beach collectible or educational specimen; calcium-carbonate shells may contribute to sediment, agricultural lime, or shell-based craft products, but this small piece has negligible commercial value.

Geological facts

The parallel ridges likely represent shell growth increments. A drop of dilute vinegar may cause effervescence if calcium carbonate is exposed, though this test can damage the specimen.

Field identification & locations

Commonly found on beaches and in shell beds; identify by its curved form, growth lines, and layered shell texture. Estimated value: under $1–$5 unless unusually large, species-identifiable, or genuinely fossilized.