It is used extensively by the railroad companies, and for local, domestic and manufacturing purposes. Limestone is found in all parts of the county. It is of an excellent quality for building purposes. A great number of the buildings of the county are constructed of this material. Besides this the stone is used to a great extent for fencing.
Yellow ochre is found in abundance in every township.
There is also an almost unlimited supply of fire and pottery clay, which is utilized to some extent. In 1878, from parts of Superior and Arvonia. In 1871, from part of Superior. In 1877, from parts of Ridgeway and Valley Brook. In 1871, from part of Valley Brook.