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The Ardis Furnace

Inventor John T. Jones of Iron Mountain recognized the economic potential of the low-grade iron ore of the Upper Peninsula. He developed a method for processing the ore and built an experimental furnace in 1908, named for his daughter Ardis, to test his theory. The furnace, a huge metal tube lined with firebrick, was placed on an incline and charged with ore. The whole device was rotated by electric motor, with iron suitable for mill use discharged from the lower end of the tube. The experiment was plagued with financial and mechanical problems, and by the close of World War I the Ardis was dismantled, Jones moving to other mining endeavors. Elements of the Jones method were later incorporated into successful processing operations for low-grade iron ores.

Plaque via Michigan History Center

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