The Hard Rock Mining Era in the Copper Country by Tauno Kilpela.

Paperback.  196 pages.
Genres:  history, nonfiction.

A chronic of operations on the seven major lodes of the Keweenaw Mining District: The Pewaubic Amygdaloid Lode, The Isle Royale Amygdaloid Lode, The Atlantic Amygdaloid Lode, The Calumet Conglomerate Lode, The Kearsarge Amygdaloid Lode, The Osceola Amygdaloid Lode, and The Baltic Amygdaloid Lode. Each section dives in depth on one of the lodes, including the mining companies that operated on them and the bedded formations contained within them.