As the photo at right illustrates, this fossilized horn coral can cut into gorgeous cabochons. This is very difficult material to find. We heard that the mine where it comes from was closed due to being included into a National Monument. However, we also heard from a reliable source that the reason for a scarcity of this fine lapidary material is access to the area has been cut off. We were fortunate to obtain this rough from old collections.

This fossil coral comes from the Silurian Age which dates to 390 million years old and falls within the Paleozoic Era.

Fossil Horn Coral is agatized. So, it cuts like agate and takes a fine polish with tin or cerium oxide and diamond. Mohs hardness 6.5 to 7.