Alliance Resource Partners is a natural resource company. The company is a coal producer in the eastern United States. The company markets its coal production to main domestic and international utilities and industrial users. The company has two reportable segments: Illinois Basin, which comprises of multiple operating segments, including operating mining complexes Webster County Coal's Dotiki mining complex, Gibson County Coal's mining complex, River View's mining complex and the Hamilton mining complex; and Appalachia, which comprises of multiple operating segments, including the Mettiki mining complex, the Tunnel Ridge mining complex, the MC Mining mining complex and the Penn Ridge property.

Contura Energy is a coal supplier with affiliate mining operations across major coal basins in Pennsylvania, Virginia and West Virginia. The company's portfolio of mining operations consists of underground mines, surface mines and coal preparation plants. In the Central Appalachia (CAAP) coal basin, the company mainly produces low-ash metallurgical coal, which are shipped to domestic and international coke and steel producers. In the CAPP coal basin, the company also produces low sulfur, high British thermal unit (BTU) thermal coal for electricity generation, as well as specialty coal for industrial customers. In the Northern Appalachia coal basin, the company produces primarily high-BTU thermal coal.

Arch Coal is a coal producer. The company's main business is the production of thermal and metallurgical coal from surface and underground mines located throughout the United Staets, for sale to utility, industrial and steel producers both in the United States and around the world. The company's segments are based on two lines of business, metallurgical coal and thermal coal, and may include a number of mine complexes. The company's segments are: the Powder River Basin, containing primary thermal operations in Wyoming; the Metallurgical, containing metallurgical operations in West Virginia; and the Other Thermal, containing supplementary thermal operations in Colorado and Illinois.

CONSOL Energy is a producer of bituminous coal, focused on the extraction and preparation of coal in the Appalachian Basin. The company's primary businesses consist of its: Pennsylvania Mining Complex; CONSOL Coal Resources LP (CCR or Partnership) Ownership, in which the company owns directly or indirectly, through CCR's general partner, an interest in the partnership; CONSOL Marine Terminal, in which through its subsidiary, CONSOL Marine Terminals LLC, the company provides coal export terminal services through the Port of Baltimore; and Greenfield Reserves, in which the company has ownership of undeveloped coal reserves located in the Northern Appalachian Basin, the Central Appalachian Basin, and the Illinois Basin.

Warrior Met Coal is a holding company. Through its subsidiaries, the company is a producer and exporter of met coal. The company sells its coal product to steel producers in Europe and South America. The company's mining operations consist of two underground met coal mines in Southern Appalachia's coal seam (Mines No. 7 and No. 4) and other surface met and thermal coal mines. The company's natural gas operations remove and sell natural gas from the coal seams owned or leased by the company and others as a byproduct of coal production. The company's degasification operations improve mining operations and safety by reducing natural gas levels in its mines. The company also owns mineral rights for recoverable reserves at its Blue Creek Energy Mine.