United States Lime & Minerals, Inc. conducts its business through two segments, Lime and Limestone Operations and Natural Gas Interests. The Company manufactures lime and limestone products, supply primarily the construction, steel, municipal sanitation and water treatment, oil and gas services, aluminum, paper, glass, roof shingle and agriculture industries and utilities and other industries requiring scrubbing of emissions for environmental purposes. Its Lime and Limestone Operations represent its principal business. It operates lime and limestone plants and distribution facilities in Arkansas, Colorado, Louisiana, Oklahoma and Texas through its wholly owned subsidiaries, Arkansas Lime Company, Colorado Lime Company, Texas Lime Company, U.S. Lime Company, U.S. Lime Company - Shreveport, U.S. Lime Company - St. Clair and U.S. Lime Company - Transportation. The Company extracts limestone from its open-pit and underground quarries.