Preliminary report on the geology of east central Minnesota, including the Cuyuna iron-ore district, Bulletin 15, Plate 2
Description
Map of the principal part of the Cuyuna Iron-ore District, showing the distribution of known iron-bearing rocks and lines of maximum magnetic attraction, scale 1 inch = 1 mile.
Harder, E.C., Johnston, A. W. (A. Walfred) (1918). Preliminary report on the geology of east central Minnesota, including the Cuyuna iron-ore district, Bulletin 15, Plate 2. Minnesota Geological Survey. https://reflections.mndigital.org/catalog/mgs:976 (map)