Where is Petoskey Stone found?
Fossilized Hexagonaria 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
Lake Michigan Shoreline (Michigan, USA)
Abundant along the beaches of Lake Michigan, especially near Petoskey, Charlevoix, and Traverse City. Wave action polishes the stones, making their patterns more visible.
Lake Huron Shoreline (Michigan, USA)
Can also be found along the shores of Lake Huron, particularly in the northeastern Lower Peninsula.
Gravel Pits and Quarries (Michigan, USA)
Found in inland gravel pits and quarries that extract glacial deposits or Devonian bedrock.
Rivers and Streams (Michigan, USA)
Washed down by rivers and streams that flow through areas with glacial deposits containing the fossilized coral.
Collecting tips
- Look on Wet Beaches. The distinctive hexagonal patterns are much more visible when the stones are wet. Search along the waterline or after a rain shower.
- Search After Storms. Storms and strong wave action can uncover new stones on beaches.
- Carry a Spray Bottle. If searching on dry beaches, a small spray bottle of water can help reveal the patterns on potential Petoskey Stones.
- Distinguish from Other Fossils. Be aware of other fossil corals like Favosites (honeycomb coral) or Halysites (chain coral), which have different patterns. The Petoskey Stone's hexagons are typically larger and more distinct.
Quick Check
- Color:
- Gray to brown with lighter hexagonal patterns.
- Luster:
- Dull to earthy (unpolished), vitreous to waxy (polished).
- Streak:
- White (as it is primarily calcite).
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