Word: oxyhydrogen
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Dates: during 1940-1949
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Ordinary sapphires and rubies are clear crystals of aluminum oxide (A12O2). The colors come from small amounts of such elements as chromium or iron. For years, both gems have been manufactured (without the stars) by passing finely powdered A12O2 through the flame of an oxyhydrogen blowpipe. The tiny particles melt and then solidify into a crystalline blob just beyond the flame. Such crystals have all the beauty, color, hardness and other desirable properties of natural gems. When they are well made, their "falsity" can be detected only by an expert who looks (with a microscope) for their slightly curving "growth...
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