NACCO Industries, Inc. (NC)
NACCO Industries, Inc., together with its subsidiaries, engages in the natural resources business.
Hallador Energy Company (HNRG)
Hallador Energy Company, through its subsidiaries, engages in the production of steam coal in the State of Indiana for the electric power generation industry.
Alliance Resource Partners, L.P. (ARLP)
Alliance Resource Partners, L.P., a diversified natural resource company, produces and markets coal primarily to utilities and industrial users in the United States.