Word: coppers
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Dates: during 1950-1959
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...Arizona, 45 miles from Tucson, lies the nation's biggest untapped source of copper. It is the 4,411-acre San Manuel field, which geologists estimate contains 460 million tons of ore-enough to last the U.S. for about three years. But it has not been exploited because the low-grade ore would be enormously expensive to mine and process...
...prints started as paintings, which were photoengraved on copper plates. Rouault reworked each plate with engraving tools, giving them a depth and richness of black-to-white values that rival even the color values of his paintings...
...Diggings. Why hasn't U.S. copper output bounced upward like steel and aluminum? The fact that even a giant like Anaconda needs the promise of a Government subsidy gives part of the answer. Like the rest of the copper industry, Anaconda has mined its richest ores, left little but high-cost ore in the ground. A hundred years ago, mined ore in the U.S. averaged 20% copper; now it averages less than...
Extracting copper from such low-grade ore is enormously expensive. To open his Nevada mine, "Con" Kelley had to buy a sulphur mine 60 miles away, to get sulphuric acid needed for the concentrating process. Because exploration is even more expensive, Kelley and others are now going through old diggings to get out the high-cost ore that had been bypassed. Anaconda alone is spending $27 million to tap 130 million tons of such ore in its famed Butte, Mont, properties and another $100 million to process low-grade ore in Chile...
There is no quick way to boost copper imports, either. The U.S. last May shelved its 2?-a-lb. tariff, and agreed to pay a premium price of 27½? for Chilean copper, which accounts for most U.S. imports. But the U.S. also had to agree to let Chile sell a big chunk of her copper in Europe and elsewhere, where the price has been as high as 50? a Ib. Result: imports have dropped...