Explore Minnesota - Iron Ore
iron silicates. Iron ore mining first occurred in Minnesota on the Vermilion Iron Range in 1884 followed by the Mesabi Iron Range (1892), Cuyuna Range (1911) and the Fillmore County District (1941). The first mines on the Mesabi exploited the so-called "natural ore", which is a weathering or alteration of the Biwabik Iron Formation along ...