Turritella Agate The unique Turritella Agate comes from the well-known Green River Formation in the states of Wyoming, Utah and Colorado in the USA. The agate consists of many fossilized snail shells of freshwater snails that lived in the lakes of that time about 50 million years ago. There were so many of these animals living in these lakes that the remains of the animals covered the entire bottom of the lake. The remains of the snails were buried in the mud over time and fossilized over the millennia, thus forming today's Turritella Agate.
