Word: coppers
(lookup in dictionary)
(lookup stats)
Dates: during 1960-1969
Sort By: most recent first
(reverse)
...boom has not been a one way ride on the gravy train for everybody. An increasing amount of time is being lost in strikes-most recently in the auto, steel-hauling and copper industries. Unemployment is down to 4.1%, from 7% at the beginning of the upsurge, but it has risen in the past year. On Wall Street, the stock market took a toboggan ride last week, with the Dow-Jones industrial average plummeting 31.56 points to a five-month low of 856.62. Though price increases had been held to 1.3% a year for nearly five years, they have averaged...
...walls, forming a pool at the bottom that will solidify into a glassy mass containing as much as 90% of the radioactive products of the A-blast. At the same time the roof of the cavern will begin to collapse, eventually forming a 440-ft. cavity filled with fractured copper...
Scientists from the AEC, the U.S. Bureau of Mines, the University of California's Lawrence Radiation Laboratory and the Kennecott Copper Corp. have proposed a test (named Project Sloop* by the AEC) near Safford, Ariz. There, under a layer of volcanic rock more than 500 ft. thick, Kennecott test drillings have revealed a 2-billion-ton reserve of ore containing about 4/10 of 1% of copper...
After about eight months-enough time for radioactivity to decrease to safe levels-mining engineers will drill three holes from the surface to the top of the "chimney" of fractured rock. Through these holes, sulfuric acid will be poured into the chimney, where it will dissolve copper out of the rock. The solution, containing copper sulfate, will then drain into holes drilled at the bottom of the chimney and be pumped up through a shaft to a precipitation plant at the surface. There the solution will be processed to extract metallic copper, and the recovered sulfuric acid recycled for another...
Project Sloop will cost an estimated $13 million, and could take 30 months from authorization through evaluation. If it works, technicians using nuclear devices as powerful as 100 kilotons may some day be able to process tens of millions of tons of ore containing copper that is now beyond man's grasp...