The famous red horn coral location at Rileys Canyon produces some of the most distinct and beautiful fossilized coral from anywhere in the world. They date back to the pennsylvanian time period (300 million years ago) and are from the Morgan formation. What was once a coral reef is now uplifted onto a mountain top. The site was dug extensively with heavy equipment many decades ago and has been closed down to commercial digging for many years. The corals especially in large sizes like this have become increasing scarce.