Stone is a fossilized coral, named Hexagonaria Percarinata,
from the Devonian Age, about 350 million years ago.
Hexagonaria Percarinata is a genus of colonial rugose coral. Rugose
is from the Latin word rugosus meaning
wrinkled, referring to the wrinkled or "corrugated"
walls between the individual coral organisms in the
colony. These coral colonies consist of tightly packed,
usually six-sided corallites, which are the skeletons
of the once-living coral polyps. At the center of each
polyp was the mouth that contained tentacles that
reached out for food. The hexagonal shape of each cell
and thin lines radiating out from the dark mouth in
the center are distinguishing features unique to this
Petoskey stones are unique
to the Traverse Group rock strata in the Gravel Point Formation. They are fragments of a coral reef that was deposited
during the Devonian period. Petoskey Stones are found in Northern Michigan near
the town of Petoskey on the southeast shore of the Little
Traverse Bay of Lake Michigan at the mouth of the Bear
River. The stones can be found on beaches and inland
in the area.
Petoskey Stones can be very attractive and interesting
when polished into cabochons.
Stones, and the town of Petoskey, are named after an
Odawa (Ottawa) Indian chief, Chief Ignatius Petosegay
(1787-1885). The name Petosegay is said to mean "rays
of the rising sun" in the language of the Odawa Indians.
It is said that if you study the fossil stone you will see
the radiating pattern of the “rays of the rising sun”
in each cell. Chief Petosegay's father was a French Canadian fur trader
and his mother was an Odawa Indian. In the summer of 1873 a city began on his land along Little Traverse Bay.
The settlers named the new city Petoskey, an anglicized form of
Petosegay, in honor of Chief Petosegay.
town of Petoskey became a summertime destination for
Victorian tourists and the unusual fossil specimens
were popular souvenirs. The tourists began referring
to the local Hexagonaria Percarinata fossils as Petoskey
Stones. This is probably because “I’m bringing
you a Petoskey Stone” was much easier to fit on a postcard
than, “I'm bringing you a Hexagonaria Percarinata fossil.”
June of 1965 the Petoskey Stone was named Michigan’s
official State Stone and Miss Ella Jane Petoskey, the
only living grandchild of Chief Petoskey, attended the
formal signing. In the city that bears his name, a bronze
statue of Chief Petosegay stands on a bluff overlooking
Little Traverse Bay.