Beneath the forests of Michigan’s UpperPeninsula lie vast iron deposits that have long resisted ore-hungrysteelmen. The ore is jasper, a diamond-hard rock that blunts ordinarydrills, is too low in iron content (about 33%) for conventionalrefining methods. Five years ago Cleveland-Cliffs Iron Co., with FordMotor Co., set up pilot operations to mine and process* jasper by a newmethod. Last week Cleveland-Cliffs and Inland Steel Co. announced thatthey will build, near Marquette, Mich., the nation’s first bigjasper-mining and processing project. At peak production the Marquetteplants will grind some 6,000,000 tons of jasper yearly, convert it into3,000,000 tons of walnut-sized pellets that contain 60% iron.
With the nation scraping the bottom of its high-grade iron deposits andsteel capacity due to rise 60% (to 216 million tons yearly) by 1980,the development of such low-grade ores as jasper and its cousin,taconite, has become one of the fastest-growing branches of the boomingsteel industry. Items:
¶ Reserve Mining Co., owned by Republic Steel and Armco, will have its3,750,000-ton taconite processing project at Babbitt and Silver Bay,Minn. in full production by May.
¶ Erie Mining Co., jointly owned by Bethlehem, Youngstown and twosmaller companies, has operated a pilot taconite plant near Aurora,Minn, since 1948, is building a $300 million plant that will start upin 1957, will have a 7,500,000-ton annual capacity.
¶ U.S. Steel has two small Minnesota taconite plants at Mountain Ironand Virginia, Minn, that ship 500,000 tons yearly, is planning a hugenew plant near by to boost annual production to more than 10 milliontons.
Though processing low-grade ore costs up to $30 per ton, the evenquality of the pellets hikes blast-furnace output as much as 20%, andproduces better pig iron. An even bigger advantage of low-grade ironore is its large supply. Only five years ago steelmen were predictingthat some of the nation’s high-grade ore deposits would be mined out by1970. By using its low-grade ore, the U.S. should have plenty of orefor another several hundred years.
* Jasper is blasted from the earth, crushed to powder, washedto rid it of some impurities, then mixed into a special oil solutionthat floats the fine particles of iron to the surface. They areconcentrated into small pellets by centrifuge.