Location: Humboldt, MI - Edison Ore Improvement Plant

In 1888, Thomas Edison constructed an electromagnetic separator plant near Humboldt Mine to extract ore from the iron ore rock. The technology was before it's time. The plant burned down in 1890 and was not rebuilt. [LSI1]

Notes

Time Line

1960. The Humboldt Mining company Friday opened an iron ore pelletizing plant with a capacity of 650,000 tons a year here. The new plant, adjacent to an open pit mine from which it will convert low-grade ores into rich iron pellets, is jointly owned by the Ford Motor Company and Cleveland-Cliffs Iron Company.

A previous plant, which converted low grade jasper rock into rich iron ore powder proved unsuccessful because the powder was too fine and light for satisfactory blast-furnace feeding. It was converted and expanded. The mine is 12 miles west of Ishpeming and 30 miles west of Marquette. The ore found in jasper rock, is non-magnetic hematite and thus cannot be separated from waste materials by magnetic processes, such as those used on Minnesota's magnetic taconites. 

The Humboldt process of separation utilizes the principle of flotation. Agents are added to the ground ore mixture, causing it to adhere to air bubbles and thereby separating ore from waste rock. The concentrate is then processed into balls which are heated to 2,450 degrees in a rotary kiln. [LSJLl-19600-091]