Central Range Mining
Wars Deplete Natural Ores, Mining Technology Changes
The
vital importance of Minnesota's
iron ore resources was not in any way lessened by the depression of the 1930s.
This was clearly shown as both the nation and the free world relied on Minnesota iron ore
throughout World War II. In all, more than 338 million tons of Minnesota iron ore were
shipped during the war years to make ships, tanks, guns and other steel
armaments.
With the
end of the war, the need for iron ore continued and even increased - 304
million tons were shipped from Minnesota
during the five years following the war, and 344 million tons were shipped
during the next five years, 1950-55. Some of this tonnage was used to meet the
needs of the Korean War, but much of it helped to meet the great consumer
demand which had built up during World War II - a demand for automobiles, new
building, roads, home appliances and all the other items required by a rapidly
growing nation.
From 1955 to
1960, a sharp decline in natural ore shipments resulted primarily from
depletion of our better grades of natural ore. At the same time, steelmakers,
seeking greater production, were getting more and more demanding about the
quality of ore they were feeding into their blast furnaces. Also, worldwide
exploration efforts, spurred by growing use of iron and steel, were beginning
to turn up vast new sources of iron ore. Iron mining was entering a new phase.
