The Gogebic iron range is in Michigan and Wisconsin, south of the western end of Lake Superior, along a narrow belt that extends about 80 miles in a general east-west direction. The range constitutes part of the south flank of the Lake Superior pre-Cambrian geosyncline. The productive part of the district extends from the vicinity of Wakefield, Michigan, westward into Wisconsin, to about the west border of Iron County, Wisconsin. The eastern part of the district, from a few miles east of Wake‐field to Lake Gogebic, has never produced any ore. In both parts of the range the Middle Huronian iron formation is overlain by a thick series of graywacke and slates, which, in turn, are overlain by the Keweenawan. In the central part of the range, near Wakefield, however, the lower Keweenawan quartzite bevels across the graywacke and rests directly upon the iron formation, so . . .