Petoskey Stone - Hexagonaria Percarinata.The stones on this card have been shaped and arranged to look like the map of of Michigan. I have to be honest and say that I didn't see it was a map until I was told.
Michigan's State Stone, Petoskey Stones, were once living coral that existed some 350 million years ago. Over time the coral became fossilized and glaciers scattered the stones along Lake Michigan near Petoskey and across Michigan to the Lake Huron shoreline.
Petoskey stones are gray and rough when found but when polished the beautiful rich coral pattern emerges. Polished Petoskey Stones have a smooth surface ans are highly prized as gifts and jewelry.
Similar coral fossils can be found in other places but Petoskey Stones must have a six-sided structure with a distinctive eye at the centre.