Edison Ore-Milling Company

The Edison Ore-Milling Company was a venture by Thomas Edison that began in 1881. Edison introduced some significant technological developments to the iron ore milling industry but the company ultimately proved to be unprofitable. Towards the end of the company's life Edison realised the potential application of his technologies to the cement industry, and formed the Edison Portland Cement Company in 1899.

Edison had recognised the scarcity of iron ore in the 1870s, particularly in the east of the United States. His developments in the field of electricity meant that he had sufficient finances to invest in other projects. Discovering that beach sand contained relatively high deposits of iron, he decided to form the Edison Ore-Milling Company in 1881. He patented a method of extracting the metal using a large electromagnet after developing the process in an addition to his laboratory. The remaining deposits of iron in the eastern side of the United States were of poor quality, and the difficulty in separating it from the rock and other debris made it unprofitable. Edison believed that his method was a cheaper alternative, allowing him to keep costs down.William Kennedy Dickson had been put in charge of much of the laboratory and further refined the techniques along with mining expert John Birkinbine. However, the market for Edison's iron was not sufficient to bring in a profit and the operation was closed down after just a few years.

After a short time away from the industry, Edison decided to return, adapting his methods to crush rocks brought up directly from a mine. He opened a plant in Bechtelsville, Pennsylvania near to existing iron mines as a trial before building one of the world's largest ore-crushing mills in Ogdensberg, New Jersey. Completed in 1889, the factory contained three giant electromagnets and was intended to process up to 1200 tons of iron ore every day. Technical difficulties repeatedly thwarted production.

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