Word: quartz
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Dates: during 1960-1969
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...ideas freely from their conquerors, they added their own craftsmanlike touches, which had been passed down through 2,000 years of Egyptian civilization. Artisans eschewed the hard-tipped metal tools used by foreign sculptors, pounded away at the quarry rock with stone cutting tools, polished the finished work with quartz sand. Details such as the echeloned curls, sinuous eyebrows, and almond-shaped eyes of the Girl with a Late Period Bob were painstakingly sculpted. So perfect was the technique of these artisans that even today no modern steel cutting tool can achieve the same sable smoothness on hard stone...
Looking around for a better measuring stick, scientists found that quartz can be made to vibrate electrically at very constant frequency. A quartz disk will keep time for short periods with the accuracy of one part in 10 billion (the equivalent of a one-second error in 300 years). But after a week or so, quartz changes its frequency in an unpredictable...
Electron Cutter. United Aircraft Corp.'s Hamilton Standard Division (propellers) will put on the market a machine, developed by West Germany's Carl Zeiss Foundation, that uses electron beams to weld, mill and drill hair-fine holes in the hardest known materials, e.g., quartz, tungsten, zirconium. An electron gun fires beams that boost the temperature on the surface of the material up to 11,000° F. ; it can cut 100 holes in a straight line across a pinhead, drill a sapphire watch bearing in six seconds, weld a tough nu clear reactor core. Lease price: about...