fossil

Fossilized Brachiopod or Gastropod

Phylum Brachiopoda / Phylum Mollusca

Hardness typically 3-4 (calcite), color ranges from grey to brown, dull to vitreous luster, amorphous fossilized shell structure with distinct ribbed growth lines.

Identified August 6, 2026More fossil →

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Physical properties

Hardness typically 3-4 (calcite), color ranges from grey to brown, dull to vitreous luster, amorphous fossilized shell structure with distinct ribbed growth lines.

Formation & geological history

Formed through permineralization where prehistoric shells buried in marine sediment were gradually replaced by minerals like calcite or silica over millions of years during the Paleozoic or Mesozoic eras.

Uses & applications

Collected by fossil enthusiasts, used in educational displays, and studied by paleontologists to understand ancient marine ecosystems.

Geological facts

Brachiopods superficially resemble clams but belong to a completely different phylum characterized by a lophophore feeding structure. They are among the most common fossils found in marine sedimentary rocks.

Field identification & locations

Can be identified in the field by looking for distinct symmetrical ribbed shells embedded in limestone, shale, or sandstone formations, often near ancient seabed exposures.

Other fossil specimens

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Crinoid Stem Fossil in Matrix

Phylum Echinodermata, Class Crinoidea

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Chert with Fossil Brachiopod

Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion

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Sedimentary Outcrop (Sandstone/Shale)

Sedimentary bedrock formation (variable composition)

sedimentary

Crinoid Stem Fossils (Indian Beads / St. Cuthbert's Beads)

Crinoid columnal ossicles (phylum Echinodermata)

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Fossilized Crinoid Stem in Limestone

Crinoidea (Class) in Calcium Carbonate (CaCO3) matrix

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Fossiliferous Limestone

Limestone with embedded fossil cross-section

sedimentary