fossil

Brachiopod Fossil in Sedimentary Matrix

Phylum Brachiopoda in Siltstone/Mudstone matrix

AI-generated identification · may be incorrect

Hardness: 3-4 (matrix), color: earthy tan to brown, luster: dull/earthy, features visible ribbing of shell impressions (costae), fine-grained clastic texture.

Identified July 6, 2026More fossil →

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Physical properties

Hardness: 3-4 (matrix), color: earthy tan to brown, luster: dull/earthy, features visible ribbing of shell impressions (costae), fine-grained clastic texture.

Formation & geological history

Formed during the Paleozoic era (approx. 250-500 million years ago) in a shallow marine environment where ancient shellfish were buried by sediment which later lithified into rock.

Uses & applications

Used primarily for scientific study (paleontology), educational purposes, and as collector specimens.

Geological facts

Brachiopods are often called 'lamp shells' because their shape resembles ancient oil lamps. Although they look like modern clams, they are biologically distinct and belong to a different phylum.

Field identification & locations

Identify in the field by looking for symmetrical 'butterfly' or 'fan' shapes with ribbed patterns in layered sedimentary rock outcrops, especially in limestone or siltstone beds.