fossil

Fossilized trilobite

Trilobita; likely an enrolled asaphid or phacopid trilobite

AI-generated identification · may be incorrect

A segmented, three-lobed exoskeleton with visible thoracic bands and a rounded enrolled form. Fossil trilobite material is commonly calcite-replaced or silicified, typically Mohs 3–7 depending on preservation, with dull to waxy luster and gray-brown, golden, or black coloration.

Identified August 13, 2026More fossil →

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Physical properties

Formation & geological history

Trilobites were marine arthropods that lived from the Cambrian to the end-Permian, about 521–252 million years ago. Burial in marine sediment followed by mineral replacement and lithification preserved the exoskeleton.

Uses & applications

Primarily a display and educational collectible; polished or prepared specimens are used in museums and paleontology collections, not typically for construction or jewelry.

Geological facts

The three-part body plan consists of a central axial lobe and two pleural lobes. Enrollment was likely a defensive behavior, protecting the underside and appendages.

Field identification & locations

Look for repeated body segmentation, bilateral symmetry, a central axial ridge, and a distinct head shield; these features distinguish trilobites from ordinary pebbles. Common sources include Morocco, Utah, China, and Russia; exact species requires better detail and provenance.