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At its peak, the Oliver Iron Mining Company operated 128 mines across the Iron Range

Oliver mines were originally clustered on the eastern end of the Mesabi.

historical photo of steam powered shovel equipment
Oliver Mining Company steam-powered shovel near Hibbing, 1919. In this method of mining, a shovel removes overburden, the rock and soil that covers the ore body, so that miners can access the ore from the open pit.
National Archives

The Oliver Iron Mining Company was one of the most prominent mining companies in the early decades of the Mesabi Iron Range. As a division of United States Steel, Oliver dwarfed its competitors — in 1920, it operated 128 mines across the region, while its largest competitor operated only sixty-five.

After the Merritt brothers began shipping iron ore from their Mountain Iron mine in 1892, Henry Oliver, a Pittsburgh businessman, traveled to the Iron Range to consider investing in the fledgling industry. Impressed by what he saw, Oliver offered to purchase one of the ore deposits for $75,000 and 65 cents per ton of ore mined. The Merritts sold Oliver the deposit, and Oliver Iron Mining Company was born.

Many early mines on the Mesabi were controlled by East Coast financiers. John D. Rockefeller bought the Merritt brothers’ holdings in February 1894. That April, Andrew Carnegie loaned Oliver $500,000 for half of Oliver’s stock so he could compete with Rockefeller. Since Carnegie owned steel mills but Rockefeller didn’t, Rockefeller had virtually no other options than to sell his ore to Carnegie. As a result, the three men reached a compromise in 1896: Oliver would mine the ore, Rockefeller’s railroad system would transport the product, and Carnegie would transform it into steel. This agreement was finalized in 1901, and United States Steel (USS) was incorporated as the largest corporation in the world.

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Oliver mines were originally clustered on the eastern end of the Mesabi. In 1900, however, investors Chester Congdon and Guilford G. Hartley acquired mineral leases on the western end of the Range near the town of Nashwauk. The ore in this area was sandier than the ore mined on the eastern end, so it needed processing in order to be used in a steel mill. This processing is called concentration because ore is concentrated into a higher-grade product. Because of the high costs associated with processing, the businessmen approached Oliver Iron Mining Company with an investment opportunity. In 1904, Oliver invested $10 million in a concentration plant that would serve this area, which the corporation referred to as the “Canisteo District.” The plant, called the Trout Lake Concentrator, transformed the region, helping existing towns like Bovey and Calumet grow. In addition, the towns of Coleraine, Marble, and Taconite were directly built by Oliver to house workers in the newly developing region.

In 1907, miners organized themselves into unions because they felt that mining companies — including Oliver — weren’t treating them fairly. A majority did not speak English and were therefore vulnerable to exploitation. When Oliver didn’t respond to a list of union demands presented that July, nearly 16,000 miners across the Mesabi went on strike. To continue operations, Oliver brought in new workers directly from Europe. When production recovered as a result, the strike collapsed and many miners returned to work — although some were blacklisted by the mining companies and never worked in a mine again. Nine years later, in 1916, miners once again went on strike. This time, Oliver hired armed guards, and in June, a dispute between strikers and guards broke out in Virginia. A picketer, John Alar, was killed and subsequently became a martyr for the cause. As the strike continued into late July, Elizabeth Gurley Flynn — a well-known American labor organizer — spoke to strikers and encouraged them to persevere, but many soon returned to work in August, effectively ending the strike.

As natural ore reserves diminished due to war effort production, Oliver turned to ore that required more processing than the rich ore that Oliver originally purchased from the Merritt brothers. While the Trout Lake Concentrator was still in operation in the Canisteo District, Oliver built the Pilotac and Extaca plants near Virginia. Pilotac was built to research methods for concentrating taconite ore, and Extaca was built to agglomerate, or combine, taconite concentrate into a high-iron product that could be used in steel mills.

Millions of dollars were invested in taconite plants throughout the Iron Range, and taconite became the chief rock mined in the region. As the Iron Range transitioned to taconite mining, United States Steel dropped the Oliver name in place of Minnesota Ore Operations.

For more information on this topic, check out the original entry on MNopedia.