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Trilobite Information

What is a trilobite?

A trilobite is a form of invertebrate marine life that lived more than 550 million years ago, but are now extinct. These hard-shelled prehistoric critters roamed the sea floor and coral reefs in search of food. Because of their great diversity and often perfect preservation in fine-grained rock, they are one of the most popular fossils among collectors.

Are the fossils easy to collect?

The fossils are found in a limestone shale. This shale splits easily into flat sheets, revealing the trilobite fossils. Fossilized trilobites lay nearly flat along the splitting planes of the shale. U-DIG Fossils can provide a hammer or you can bring your own. If you desire to remove your own fresh rock, larger tools are available. There’s little need to do this, though. Fresh chunks of fossil-bearing rock are regularly extracted and exposed from the bedrock with heavy equipment by the U-DIG staff.

How many fossils will I find?

The average visitor finds ten to twenty trilobites in a four-hour period. If you’re having trouble, friendly U-DIG personnel roam the Quarry area and would be glad to show you the richest veins of fossil-bearing rock. They can show you how to split the rock to find trilobites, and can identify what you find.

What sort of trilobites will I find?

The most common species found at the Quarry are: Elrathia kingiAsaphiscus wheeleri, and Peronopsis interstricta

Some of the species below have been found, but are quite rare: Bolasidella housensisAlokistocare harrisi, and Olenoides nevadensis

Other types of fossils can be found, including brachiopods, sponges, worm tracks, and phyllocarids. The quarry is part of the House Range, dated mid-Cambrian. The fossils range in length from 1/8th inch to two inches.