Petoskey stones are fossilized coral fragments of an ancient coral reef deposited during the Devonian periods of over 400 mya. The stones have a distinctly mottled six-sided pattern often resembling a patch work quilt. Petoskey stones are found along the shores, gravel pits and roads of northeastern Lake Michigan typically from Traverse City to the Upper Peninsula. In 1965 the stone was adopted as the state stone of Michigan. The detail of these beautiful stones is remarkable.
Rocks collected and photograph taken at Torch Lake Nature Preserve, Michigan.
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