fossil

Fossil scallop/bivalve shell

Fossilized pectinid bivalve; likely family Pectinidae (exact genus/species cannot be determined from the image)

AI-generated identification · may be incorrect

A ribbed, fan-shaped shell preserved in pale cream carbonate mineral, with partial bilateral symmetry and strong radial ribs. Original aragonite is commonly replaced or coated by calcite; calcite hardness is Mohs 3, with a dull to slightly pearly luster and cleavage.

Identified August 8, 2026More fossil →

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Physical properties

Formation & geological history

A marine bivalve lived on the seafloor, was buried in sediment, and became mineralized during diagenesis. Its age may range from Paleozoic to Cenozoic; the image alone cannot establish a geologic age.

Uses & applications

Primarily a collectible, educational specimen, or decorative fossil; it has negligible industrial value compared with quarried limestone or shell aggregate.

Geological facts

Radial ribs strengthened the living shell and are characteristic of scallops and related bivalves. The rough surrounding material is likely lithified carbonate matrix.

Field identification & locations

Identify it by the fan shape, hinge region, and regular radial ribs; dilute hydrochloric acid will effervesce on exposed calcite, but testing can damage it. Similar fossils occur in marine limestones worldwide, including North America, Europe, and Asia.