Martin Marietta Materials, Inc. is the producer of aggregates products (crushed stone, sand, and gravel) for the construction industry, including infrastructure, nonresidential, residential, railroad ballast, agricultural, and chemical grade stone used in environmental applications. The Company operates in four business segments: the Mideast Group, Southeast Group, and West Group and the Specialty Products segment. The Specialty Products segment includes the magnesia-based chemicals and dolomitic lime businesses. Effective April 3, 2014, Martin Marietta Materials Inc acquired the remaining undisclosed stake, which it did not already own, in Hunt Martin Materials LLC, from its joint venture partner, Hunt Midwest Enterprises Inc. In July 2014, the Company acquired Texas Industries Inc.