The Company operates the Stillwater Mine near Nye, Montana, and the East Boulder Mine south of McLeod, Montana. Both mines are located along the J-M Reef, the richest known deposit of platinum group metals (PGMs) in the world.

Stillwater Mine

Feasibility and baseline studies for the Stillwater Mine were first undertaken in the 1970s after the palladium-rich J-M Reef was identified within the Stillwater Complex. By the mid-1980s an Environmental Impact Statement and a Hard Rock Mine Impact Plan were completed. Initial construction of the Stillwater Mine was completed in 1986 and underground mining commenced that year. The mine has been continually developed and expanded since initial construction was completed. A 1,950-foot (590-meter) vertical shaft was constructed between 1994 and 1996. The Stillwater Mine operations now extend laterally approximately 7 miles (11.3 kilometers) east to west and vertically more than one mile (1.6 kilometers). The Stillwater Mine currently provides over 60 percent of the Company’s total PGM production.

  • Stillwater Mine Attributes
  • Accesses the eastern portion of the J-M Reef
  • Elevations of 1,950 to 7,300 feet (590 to 2,200 meters) above sea level
  • J-M Reef is accessed by a 1,950-foot (590-meter) vertical shaft, ramps and declines, and by a system of horizontal adits (nearly horizontal entrances) and drifts (passageways between tunnels)
  • The Blitz development project commenced at the Stillwater Mine in 2010 and remains in progress

East Boulder Mine

The East Boulder Mine, the smaller of our two mines, accesses the western portion of the J-M Reef and was initially permitted in 1992. The Environmental Impact Statement and Hard Rock Mine Impact Plan for the East Boulder Mine were updated in 1998. Construction of the East Boulder Mine began in 1999. Two 3.5-mile (5.6-kilometer) portals were bored to access the ore. Most of the major above-ground facilities and infrastructure were completed in 2000, and commercial production commenced in 2002. Graham Creek, a major project to expand operations, was completed in 2014. The East Boulder Mine area extends approximately 4 miles (6.4 kilometers) horizontally by 2,000 feet (610 meters) vertically.

  • East Boulder Mine Attributes
  • Accesses the western portion of the J-M Reef
  • Independent of the Stillwater Mine
  • J-M Reef is accessed by two 3.5-mile portals (5.6 kilometer), ramps and declines, and drifts (passageways between tunnels)