Martin Marietta Materials is one of the United States' largest producer of construction aggregates (crushed stone, sand, and gravel). In 2018, Martin Marietta sold 171 million tons of aggregates. Martin Marietta's most important markets include Colorado, Florida, Georgia, Indiana, Iowa, Maryland, Nebraska, North Carolina, South Carolina, and Texas, accounting for 85% of sales. The company also produces cement in Texas and uses its aggregates in its asphalt and ready-mixed concrete businesses. Martin's specialty product business produces magnesia-based chemical products and dolomitic lime.