The Michigan Limestone and Chemical Company, founded in 1910, began operation in 1912. Purchased by Carl D. Bradley and the United States Steel Corporation in 1920, the company came under the ownership of U.S. Steel upon Bradley's death in 1928. In 1951 the company became a division of the corporation. Self-unloaders of the division's Bradley Transportation Line carry limestone from this, the world's largest limestone quarry, to industrial ports around the Great Lakes.