Fossilized Coral

Date: Mississippian Period (sub period of Carboniferous Period, 359-318 million years old)

Description: This is a fossil of an ancient coral, most likely a now extinct species similar to modern Great Star Coral, though it could also be a sponge. Coral fossils abound in the Siouxland region in our numerous limestone deposits. These fossils tell of ancient Iowan seas and the now extinct creatures that used to live and thrive in them. Corals generally live in warm, shallow waters, like the ancient Western Interior Sea that spread across this region, and form colonies that often spread into reefs. They secrete calcium carbonate, or calcite, to form a hard skeleton, and this calcite is a major component of this region’s limestone.


Donor information not available.


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