Mine: Columbia Mine, Crystal Falls, MI
Began → Columbia Mine → Tobin mine shaft
Location: NW Sec. 31 of T43N-32W
Owned by: Corrigan McKinney Steel Col; now Republic Steel Corp.
Produced: Iron Ore
Method: Underground, worked by sub-level stoping. Depth: 1,783 feet.
Railroad connection: C&NW/ MILW pool to Escanaba docks.
Lifetime Production: 4,308,6021 from 1882 to 1950. Continues.
Columbia ore is taken through the Tobin shaft. Tobin and columbia together comprise the old Sheldon Mine and the Shafter property.