Iron Range

Iron Range refers collectively or individually to a number of elongated iron-ore mining districts around Lake Superior in the United States and Canada. Despite the word "range," the iron ranges are not mountain chains, but outcrops of Precambrian sedimentary formations containing high percentages of iron. These cherty iron ore deposits are Precambrian in age for the Vermilion Range, while middle Precambrian in age for the Mesabi and Cuyuna Ranges. Similarly, the Gogebic Range in Wisconsin and the Marquette Iron Range and Menominee Range in Michigan. Natural ores and concentrates were produced from 1848 until the mid 1950s, when taconites and jaspers were concentrated and pelletized started to become the major source of iron production.

The far eastern area, containing the Duluth Complex along the shore of Lake Superior, and the far northern area, along the Canada–US border, of the region are not associated with iron ore mining. Due to its shape, the area is collectively referred to as the Arrowhead region of the state.

The area consists of seven counties: Aitkin, Carlton, Cook, Itasca, Koochiching, Lake, and Saint Louis.

From a geological perspective, the Iron Range in Minnesota includes these four major iron deposits:

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