Trilobite 
Elrathia kingii

These are specimens of Elrathia kingii, a Cambrian period trilobite from the Wheeler Shale in Utah, some 515 Million years old. Quite common trilobites, they are preserved in a black calcite that shows beautifully against the gray matrix, and specimens of Elrathia grace collections all over the world.

Trilobites are a type of extinct arthropod probably most closely related to modern Horseshoe crabs. With a growing number of predators and adapted to diverse habitats, various species of trilobites developed eyes, retractable antennae, and even protective spines. Trilobites range in size from a fraction of an inch to over two feet in length. Their exoskeletons were composed of extremely hard calcite and calcium phosphate minerals to protect the soft internal organs, and as a result they are quite well represented in the fossil record. 

These Trilobites make a beautiful and affordable addition to any collection. A fascinating peek into the depths of time, they make educational and inspirational gifts for young naturalists!

Individual fossils vary, but yours will resemble the pictured examples.