fossil

Fossilized Trilobite Pygidium / Glabella Fragment

Trilobita (e.g., Phacops or Ceraurus sp.)

Hardness: 3-4 (CaCO3/Calcite or Silica replacement), Color: Off-white to cream/tan, Luster: Dull to earthy, Texture: Highly tuberculated/bumpy surface with segmented skeletal features, Specific Gravity: ~2.7

Identified July 26, 2026More fossil →

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Physical properties

Formation & geological history

Formed through the mineralization of the exoskeleton of ancient marine arthropods during the Paleozoic Era (Ordovician to Devonian periods, ~350-480 million years ago) in shallow marine environments.

Uses & applications

Educational displays, paleontology studies, private collections, and decorative fossil specimens.

Geological facts

Trilobites are extinct marine arthropods that dominated Paleozoic oceans for over 270 million years before going completely extinct during the Permian-Triassic extinction event.

Field identification & locations

Identified by the distinct granular, pustules-covered surface texture typical of trilobite cephalon or pygidium fragments. Commonly found in Paleozoic limestone and shale deposits worldwide, especially in the US (Ohio, New York, Utah), Morocco, and Russia.

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Chert with Fossil Brachiopod

Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion

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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

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Fossiliferous Limestone

Fossiliferous Calcilutite / Biomicrite

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