fossil

Fossil trilobite, likely enrolled specimen

Trilobita; exact genus/species cannot be determined from the image

AI-generated identification · may be incorrect

Dark gray, metallic-to-matte, heavily weathered exoskeleton with repeated thoracic segments and a rounded enrolled shape; trilobite calcite exoskeletons commonly have Mohs hardness about 3–4 and may be replaced or coated by iron minerals.

Identified August 13, 2026More fossil →

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Physical properties

Formation & geological history

Trilobites were marine arthropods that lived during the Paleozoic Era, about 521–252 million years ago, and were buried in marine sediments before fossilization by compaction, mineral replacement, or pyritization.

Uses & applications

Primarily collected, displayed, and used educationally; complete, well-prepared specimens may have significant fossil-market value.

Geological facts

The repeated ridges are likely thoracic segments, while the broad end is probably the cephalon or pygidium. Enrollment was a defensive posture, analogous to a modern pill bug.

Field identification & locations

Look for bilateral symmetry, a three-lobed body plan, segmented thorax, and curved exoskeletal margins; common sources include Morocco, China, Russia, and the United States. The image may show a cast, fragment, or highly weathered specimen rather than a complete trilobite.