Bedrock geology at the south-central part of the North Range, Cuyuna district, Minnesota

The Cuyuna iron-ore district is in central Minnesota in Morrison, Crow Wing, and Aitkin Counties.  The length of the district is about 68 miles, extending from near Randall in Morrison County ot a point 11 miles east of the community of Hassmann in Aitkin County, and the maximum know width is about 25 miles near the center of the district.  Current mining activity is confined to a much smaller area about 10 miles longs and 3 miles wide near Crosby and Ironton in Crow Wing County.  This investigation has been restricted to the active area plus a marginal strip in which much exploratory drilling has been done.  The average annual production of iron ore and manganiferous iron ore from the district during 1940-50 was slightly more than 3 million tons.