fossil

Fossil brachiopod shell

Brachiopoda; exact genus/species indeterminate

AI-generated identification · may be incorrect

Small, fan-shaped, strongly ribbed shell with bilateral symmetry and brown mineralized coloration; original calcite shell, Mohs hardness about 3–4, typically dull to lightly lustrous. The visible valve appears cemented or partly replaced by sediment/minerals.

Identified September 7, 2026More fossil →

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Physical properties

Formation & geological history

A marine brachiopod fossil, likely Paleozoic or Mesozoic, formed when a calcitic shell was buried and preserved in sedimentary rock. Precise age requires matrix, locality, and microscopic examination.

Uses & applications

Primarily a teaching, collecting, and display specimen; not generally used for jewelry or construction.

Geological facts

Brachiopods resemble clams but have symmetry through each shell valve rather than between the two valves. Ribbing and a compact, unequal-valve form are characteristic of many fossil brachiopods.

Field identification & locations

Identify by the ribbed fan shape, hinge area, and bilateral valve symmetry; bivalves usually show symmetry between valves. Common in fossil-bearing limestones and shales worldwide, especially Paleozoic marine strata.