Martin Marietta Materials Inc. is the United State's second largest producer of construction aggregates in the United States. Based in Greensboro, N.C., the firm offers supplying services of several products, such as crushed stone, sand and gravel used to build the roads, sidewalks and foundations. Martin Marietta Materials Inc. also offers an array of products, including asphalt and concrete; magnesia chemicals and lime; flue gas desulphurization, composite materials and surplus equipment, to name a few. Martin Marietta Materials Inc. is incorporated as part of the Martin Marietta Corporation. The firm is ranked as No.1 World's Most Admired Company for Building Materials Industry by Fortune Magazine.