fossil

Trilobite fossil

Fossilized trilobite; exact genus/species indeterminate

AI-generated identification · may be incorrect

A segmented, three-lobed exoskeleton with a rounded cephalon and repeated thoracic segments is visible. Original calcite/chitinous material is commonly replaced or preserved in limestone; hardness is typically about 3–4, with dull gray-brown luster and no true crystal cleavage.

Identified August 18, 2026More fossil →

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Physical properties

Formation & geological history

Trilobites were marine arthropods that lived from the Cambrian to the Permian, approximately 521–252 million years ago. This specimen likely formed by burial and mineral replacement or compression in fine-grained marine sediment.

Uses & applications

Primarily a teaching, display, and fossil-collecting specimen; it has no industrial use. Value depends heavily on completeness, preparation quality, locality, and taxonomic identification.

Geological facts

The apparent axial lobe and paired lateral lobes are characteristic of trilobites, while the transverse divisions represent thoracic segments. The image may show a partial or weathered specimen, possibly embedded in or removed from matrix.

Field identification & locations

Common collecting localities include Morocco, the United States, Canada, China, and Scandinavia. Identify it by its bilateral symmetry, three-lobed body plan, segmented thorax, and calcitic fossil texture; exact identification requires the underside and locality data.