Term: Gogebic Boom (mining)
The discovery of high grade Bessemer ore in paying quantities on the Montreal or Gogebic range in 1885 led to the greatest speculative mining craze that ever swept Wisconsin. The boom reached its height late in 1886, and collapsed in 1888. During its existence fortunes were made and lost. Shares in mere holes in the ground which were given names were sold at improvised stock exchanges in Ashland, Milwaukee and Chicago. A number of really valuable properties were opened, shares in which sold at valuable prices, and became the hope and promise of all the others. Never before in the history of the state were so many people of all classes carried away by the speculative mania. During the period of the "boom" much more money was put into stocks than was taken out in the succeeding ten years; nevertheless the range has developed and is now  one of the great ore producing districts of the world.
View pictures relating to mining at Wisconsin Historical Images.
[Source: Wisconsin: comprising sketches of counties, towns, events, institutions, and persons, arranged in cyclopedic form, ed. by Ex-Gov. Geo. W. Peck (Madison, Wis., Western Historical Association, 1906).