fossil

Trilobite fossil in matrix

Trilobita (arthropod fossil; exact species cannot be determined from the image)

AI-generated identification · may be incorrect

Rounded brown-gray specimen with raised, segmented exoskeleton-like ridges in a fine-grained matrix. Fossil material is commonly replaced or preserved as calcite, pyrite, or iron oxides; hardness and luster depend on the minerals present.

Identified September 27, 2026More fossil →

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Physical properties

Formation & geological history

Trilobites lived in marine environments from the Cambrian to the end of the Permian, about 521–252 million years ago. Their remains were buried in sediment and fossilized through mineral replacement or preservation in the rock.

Uses & applications

Primarily collected for education and display; complete, well-defined specimens can be valuable, while fragmentary examples are common.

Geological facts

Trilobites are extinct marine arthropods named for the three lengthwise divisions of their body. The visible segmented pattern is consistent with a trilobite, though the photograph does not show enough detail for species identification.

Field identification & locations

Look for a three-lobed body with repeated transverse segments and a distinct head and tail; common fossil-bearing rocks include shale and limestone. Notable deposits occur in Morocco, the United States, and China.