Kasota limestone

Kasota limestone or simply, 'Kasota stone,' is a dolomitic limestone found in southern Minnesota. This sedimentary rock is part of the Oneota Dolostone Formation of southern Minnesota and is approximately 450 million years old (lower Ordovician Period). This particular limestone is rich in dolomite and magnesium, making it resistant to weathering, and it is thus widely used as a building material. Its name is taken from Kasota Township where the stone has been quarried.

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