fossil

Bivalve Fossil (Clam)

Class Bivalvia, likely Mercenaria or similar genus

AI-generated identification · may be incorrect

Hardness: 3-4 (Calcite/Aragonite); Color: Tan, white, and grey with concentric growth lines; Luster: Dull to sub-pearly; Structure: Hinged two-part shell

Hardness: 3-4 (Calcite/Aragonite)
Color: Tan, white, and grey with concentric growth lines
Luster: Dull to sub-pearly

Identified July 1, 2026More fossil →

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Physical properties

Hardness: 3-4 (Calcite/Aragonite); Color: Tan, white, and grey with concentric growth lines; Luster: Dull to sub-pearly; Structure: Hinged two-part shell

Formation & geological history

Formed when a marine mollusk died and its shell was buried in sediment. Over time, minerals like calcite or silica replaced the biological material. These can range from the Paleozoic era to the Holocene.

Uses & applications

Educational tools, decorative items, and items for specimen collection. Shells are also precursors to limestone formation.

Geological facts

Bivalves are one of the most successful groups of marine animals and have existed for over 500 million years. They are commonly used by geologists to date sedimentary rock layers.

Field identification & locations

Identified by the symmetrical, fan-like or oval shape with visible growth rings (striae). Commonly found in sedimentary basins, riverbeds, and coastal regions.