Martin Marietta Materials
Martin Marietta Materials is in the aggregate, chemical, and composite material business. It is the second largest producer of crushed stone, sand, and gravel in the United States behind Vulcan Materials Company. It is a leading U.S. producer of magnesia-based chemical products used as additives in applications including ceramics, paper, sugar, animal feed, and water treatment. It produces domolitic lime used as a fluxing agent by the steel industry.