fossil

Fossil brachiopod shell

Indeterminate articulate brachiopod; possibly a terebratulid or rhynchonellid

AI-generated identification · may be incorrect

Small, cream-colored, bilaterally symmetrical bivalved shell with a pronounced fold and sulcus, fine growth lines, and dull calcitic luster. Brachiopod shells are commonly calcite, with Mohs hardness about 3–4 and specific gravity near 2.7–2.9.

Identified August 16, 2026More fossil →

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Physical properties

Formation & geological history

A marine filter-feeding animal preserved as a mineralized shell, likely Paleozoic to Mesozoic in age; exact age requires locality and matrix examination. Fossilization typically involved burial and lithification in shallow-marine sediment.

Uses & applications

Primarily a collector’s specimen and educational fossil; it has no practical industrial or jewelry use unless incorporated into decorative materials.

Geological facts

Brachiopods resemble clams but have valves arranged dorsally and ventrally rather than left and right. The strong symmetry and central fold are characteristic clues.

Field identification & locations

Identify by its symmetry, unequal valves, central fold/sulcus, and often visible growth lines; clam shells are usually asymmetrical across the hinge. Common in marine limestone worldwide, especially Paleozoic formations.