This interesting stone is a variety of calcite. It was formed by the fossilization of ancient coral, hexagonaria. The coral lived in shallow waters and today's fossil often includes ancient silt and mud. Petoskey stones are found on many beaches of Lake Michigan and Lake Huron, as well as in rock quarries from Traverse City to Alpena, Michigan. This is the official stone of the state of Michigan.

Approximately 1.5-2.5 inches in diameter.

Price: $26.00 per knob