The Jones Furnace on the day it was first lit in 1914. John Tyler Jones is standing in the front on the far left between the two young girls. (Photo courtesy of the Marquette Regional History Center)

Have you ever noticed the rubble stone and concrete monoliths at the east end of Northern Michigan University’s Jacobetti Center parking lot? They are the remains the Jones Furnace owned by the New Process Metals Company. It was the last of four experimental forges built by John Tyler Jones of Iron Mountain between 1904 and 1914. The other forges were located in Salt Lake City, Utah and Iron Mountain and Republic, Michigan.

Jones, a skilled mechanic, engine operator and superintendent of the Hamilton Mine in Menominee, was fifty years ahead of his time. He envisioned the day that the high-grade iron ore would run out and his forges were built for the purpose of using low grade iron ore.

Low grade iron ore is more than 15 to less than 60 percent iron and usually found in banded iron formations (BIFs) which appear exclusively in Precambrian rock. Precambrian, sometimes called Cryptozoic, is the geological time period that occurred 4.5 billion to 542 million years ago. Banded iron formations are known as taconite in North America.

The mining of low-grade ore requires the removal of tremendous amounts of ore and overburden as well as beneficiation which makes it uneconomical to mine. Beneficiation is the process of crushing, milling, gravity separation and screening.

Had they been successful, the four Jones furnaces were designed to be easily and cheaply built at the mine site itself thus reducing the cost of transporting the ore and waste. The experimental process involved chemical, electrical and metallurgical processes and was known as the Jones step process.

The land for the experimental Jones Furnace in Marquette was donated by John M. Longyear, one of the investors, with the understanding that if the experiment was successful the land would then be leased from Longyear. Construction began in May 1914 and by July, 20 to 25 men were employed.

Buildings from the DuPont Powder Company, located near the present Tourist Park, which had been dismantled after an explosion, were moved for use at the new forge. The Marquette plant was eleven times the size of the first forge in Utah. The stack of the plant was 60 feet tall.

Even with the reuse of the DuPont buildings, the construction and continuous redesign of the furnace meant costs were estimated to be one quarter of a million dollars. In addition to John M. Longyear, investors included the Lee Higginson Company and Seth Gano, both of Boston, Massachusetts.

As construction neared completion, low grade manganese ore from the Cuyuna Range in Minnesota was used, while water for the process was drawn from a nearby swamp. The ore and fuel, either coal or charcoal, were poured into a slanted, brick-lined pipe that was turned by an electric motor. The concept was to concentrate the ore so it could be separated, metallized by the escaping gas and de-oxygenated producing iron up to 98 percent purity with charcoal and coke as the byproduct.

The furnace turned out its first metal on November 7, 1914. Problems occurred, as with any experimental process, one was finding material that could withstand the temperatures in the stack which often reached 2,500 degrees Celsius (4,532 degrees Fahrenheit) and often melted the steel spout on the end of the stack. Air intake holes were also sealed by the melted silica.

The plant closed without any fanfare, after just a year or two. The lack of real success, the high cost of operation and the fact that high grade iron ore was still plentiful were the key reasons for the closure. By January 1918 dismantling had begun and parts of the plant were salvaged and sold to other companies. The Hanna Mining Company of Wakefield bought the stack and used it for drying iron ore.

All that is left of the New Process Metals Company is the skeletal remains to be seen by the joggers and bicyclist as they go by on the multi-use pathway and ask themselves “I wonder what that was?”