fossil

Bivalve Fossil (Shell-bearing Sedimentary Rock)

Class Bivalvia (Phylum Mollusca) within a Calcarenite/Sandstone matrix

AI-generated identification · may be incorrect

Hardness: 3-4 (calcite shells), color: grayish-brown, luster: dull to sub-pearly, texture: clastic and biogenic, features: preserved ribbed shell structures and hinges.

Identified July 8, 2026More fossil →

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Physical properties

Hardness: 3-4 (calcite shells), color: grayish-brown, luster: dull to sub-pearly, texture: clastic and biogenic, features: preserved ribbed shell structures and hinges.

Formation & geological history

Formed during the Phanerozoic eon in a shallow marine environment where shells were buried by sediment, eventually lithifying through pressure and mineral cementation.

Uses & applications

Paleontological study, educational specimen, and collectible natural history item.

Geological facts

Bivalves are one of the most successful groups of marine animals and have existed for over 500 million years. This specimen shows a coquina-like cluster where multiple organisms were buried together.

Field identification & locations

Identify by the presence of symmetrical hinged shells (valves) with ribbing patterns embedded in a sandy or silty matrix. Common in sedimentary basins worldwide.