The lower peninsula contains the Michigan Basin, an area of sedimentary rocks covered by glacial deposits. The upper peninsula is more mineralogically diverse with large deposits of native copper (the Keweenaw peninsula) in Keweenaw, Houghton and Ontonagon counties. Precambrian iron formation was mined in the Gogebic, Marquette and Menominee iron ranges in Gogebic, Iron, Dickinson and Marquette counties. There are also kimberlites and gold deposits in this part of the state.
References:
- E. W. Heinrich and G. W. Robinson (2004): Mineralogy of Michigan, xx pp.