fossil

Fossilized Brachiopod

Brachiopoda (Phylum)

Mohs hardness typically 3-4 (calcite/silica preserved), gray to tan-brown color, dull to earthy luster, shell structure with bilateral symmetry and distinct ribbed ornamentation.

Identified July 29, 2026More fossil →

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Physical properties

Mohs hardness typically 3-4 (calcite/silica preserved), gray to tan-brown color, dull to earthy luster, shell structure with bilateral symmetry and distinct ribbed ornamentation.

Formation & geological history

Formed in ancient shallow marine environments through the replacement of organic shell material by minerals like calcite or silica over millions of years (Paleozoic to Mesozoic eras).

Uses & applications

Used in educational displays, paleontological research, and as collector specimens.

Geological facts

Brachiopods are one of the most common fossil types found globally, often mistaken for clams, though they belong to a completely different phylum with top and bottom valves rather than left and right.

Field identification & locations

Easily identified in the field by their characteristic symmetrical ribbed shells embedded in sedimentary rock such as limestone or shale. Common worldwide.