Where is Petoskey Stone found?
Hexagonaria percarinata (fossilized coral)
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Open the appPetoskey Stone occurs in specific geological environments. Knowing where to look, and in what kind of rock, is the difference between going home empty-handed and finding a great specimen.
Where to find Petoskey Stone
Michigan, USA
Primarily found in the northern Lower Peninsula of Michigan, particularly along the shores of Lake Michigan and Lake Huron. Key locations include Petoskey, Charlevoix, Traverse City, and other beaches and gravel pits in the region. It is the state stone of Michigan.
Other Devonian Outcrops
Similar fossilized corals (though not specifically Hexagonaria percarinata or 'Petoskey Stone' by common name) can be found in other regions with Devonian-aged marine sedimentary rocks, such as parts of New York, Indiana, and Ohio in the USA, and various locations globally.
Collecting tips
- Search on Beaches. The best time to find Petoskey Stones is after a storm or during early spring when ice melt and wave action have churned up the lake bottom and deposited new stones on the shorelines of Lake Michigan and Lake Huron.
- Look for Wet Stones. The distinctive hexagonal pattern is much more visible when the stone is wet. Carry a small spray bottle of water or look for stones near the waterline.
- Examine Gravel Beds. Gravel pits and road cuts in northern Michigan can also yield Petoskey Stones, as these often expose glacial till containing the fossils.
- Distinguish from Other Rocks. Look for the characteristic 'honeycomb' or 'turtle shell' pattern. Other common beach rocks like limestone or granite will not have this distinct fossil structure.
Quick Check
- Color:
- Gray to tan with lighter hexagonal patterns.
- Luster:
- Dull to earthy (unpolished), vitreous to waxy (polished).
- Streak:
- White (due to the chert/chalcedony composition).
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