fossil

Fossil brachiopod shell

Likely spiriferid or strophomenid brachiopod; calcium carbonate (primarily calcite)

AI-generated identification · may be incorrect

Hardness about 3–4 Mohs; gray-brown, dull to pearly luster, strongly convex and layered/ribbed shell with visible growth lines. The specimen appears mineralized and partially worn, with possible bilateral symmetry and a hinge margin.

Identified August 8, 2026More fossil →

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Physical properties

Formation & geological history

A marine brachiopod shell preserved in limestone or mudstone, later exposed by weathering; likely Paleozoic (approximately 540–250 million years old), though precise age requires locality and examination.

Uses & applications

Primarily a collector, educational, and decorative specimen; fossils of this type have little industrial value unless part of museum-quality material.

Geological facts

Brachiopods resemble clams but differ anatomically: their two valves are unequal and arranged dorsally/ventrally rather than left/right. They were especially abundant in Paleozoic seas.

Field identification & locations

Look for a hinge line, unequal valves, radial ribs or concentric growth bands, and bilateral symmetry; distinguish it from a bivalve by the valve arrangement. Common in Paleozoic marine limestones worldwide, including North America, Europe, China, and Australia.