Mont. Code Ann. § 50-72-101

This chapter shall apply to all mines (except coal and lignite) and individuals, owners, lessors, lessees, agents, partnerships, corporations, managers, operators, or employers operating any surface or underground metal or nonmetallic mines in this state. These individuals, owners, lessors, lessees, agents, partnerships, corporations, managers, operators, or employers operating any surface or underground metal or nonmetallic mines (excluding coal and lignite) shall report the same to the department, state the name of the mine, the location of the same, the name of the company, person, or persons owning or operating the same, post-office address, and number of persons employed.