Rock Identifier
Fossil brachiopod shell (Brachiopoda; likely a ribbed Paleozoic brachiopod, exact genus uncertain from the image) — fossil
fossil

Fossil brachiopod shell

Brachiopoda; likely a ribbed Paleozoic brachiopod, exact genus uncertain from the image

AI-generated identification · may be incorrect

The specimen is a pale, strongly ribbed shell fossil with rusty-brown staining. Original shell material is commonly calcite; calcite has Mohs hardness 3 and a vitreous to pearly luster, though fossilization may alter its composition.

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Physical properties

The specimen is a pale, strongly ribbed shell fossil with rusty-brown staining. Original shell material is commonly calcite; calcite has Mohs hardness 3 and a vitreous to pearly luster, though fossilization may alter its composition.

Formation & geological history

Brachiopods lived on ancient seafloors, where shells were buried in sediment and fossilized. Ribbed forms are common in Paleozoic rocks, especially Devonian–Carboniferous strata, but age cannot be determined from the image alone.

Uses & applications

Primarily collected and displayed; fossils also help identify and correlate sedimentary rock layers.

Geological facts

Brachiopods resemble clams but have distinct upper and lower valves, unlike the left-right valves of bivalves.

Field identification & locations

Look for bilateral symmetry down the middle of each valve and radiating ribs; common in marine limestone and shale worldwide. The visible ribbing supports brachiopod identification, but the genus requires closer examination.

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