The Petoskey Stone, Michigan’s official state stone, is a coral that was picked up by glaciers and deposited in the northwestern portions of Michigan’s lower peninsula. These fragments from the coral reef were originally deposited in the Devonian Period about 350 million years ago! Petoskey stones are found only in Michigan, on many beaches of Lake Michigan and Lake Huron as well as in rock quarries from Traverse City to Alpena. Petoskey (Hexagonaria percarinata) is a roughly hexagon shaped coral with lines radiating from the “eye” of each hexagon. The polished coral fossil makes stunning jewelry and collectable art pieces.


A blue to green stone that washes up on the shores of Leland and Elk Rapids, Michigan. They are not stones but glass left over as a byproduct of smelting iron during the 1870′s. As a cauldron of hot iron melts, limestone is tossed in as a flux, and the molten dirt floats to the top and is skimed off to form glass. Then, as the story goes, the chunks of glass were used as fill for breakwalls or dumped anywhere, often in Lake Michigan. Through the decades it has been tumbled by the waves of Lake Michigan. Although scarce, it can make beautiful recycled jewelry and art.




Cladopora are branches of coral (formed similar to the bleached white coral you see in pet stores)that have been buried in compressed mud (shale). Cladopora is best described as a staghorn coral.  It often occurs as a grey-white coral in a jet black stone saturated with crude oil, which is what gives the stone its color. It is said that it will foster general psychic awareness.