What is a Petoskey Stone? According to Wikipedia --
A Petoskey stone is a rock and a fossil, often pebble-shaped, that is composed of a fossilized coral, Hexagonaria percarinata. The stones were formed as a result of glaciation, in which sheets of ice plucked stones from the bedrock, grinding off their rough edges and depositing them in Michigan's Upper Peninsula, and the northwestern (and some in the northeastern) portion of Michigan's lower peninsula. In some areas of Michigan, complete fossilized coral colony heads can be found.
Petoskey stones are found in the Gravel Point Formation of the Traverse Group. They are fragments of a coral reef that was originally deposited during the Devonian period.  When dry, the stone resembles ordinary limestone but when wet or polished using lapidarytechniques, the distinctive mottled pattern of the six-sided coral fossils emerges. It is sometimes made into decorative objects. Other forms of fossilized coral are also found in the same location.
In 1965, it was named the state stone of Michigan.
It is a tradition for us to take visitors to a park on lake Michigan to hunt for Petoskey Stones. I happen to be quite good at spotting them while others often have difficulties:) We showed Shawn what they looked like and started hunting. Years ago we used to find a lot more. I found several and was happy when Shawn found one!
Pulled out lots of old chipboard circles which I inked, painted and stamped.