The gas-liquid impurity content and diffusivity of natural quartz grain (0.1 - 0.5 mm) of different deposits and of different enrichment methods have been studied by an original kinetic technique of mass spectrometry. Water is the quantitatively basic and the most important impurity in investigated samples. Release of water as well as the most of other impurities at vacuum annealing is observed within two temperature ranges. The quality of glass melted from quartz grains correlates with the amount of "high-temperature" form of water. For quartz with a minimum of structural defects the temperature dependence of the water diffusion coefficient isD(m~2 · s~(-1)) = (1.4_(-0.4)~(+0.6)·10~(-9) exp[-(110 ± 4) (kJ · mole~(-1)) / RT]In accordance with the results of analysis of the gas-liquid impurities in quartz raw three criteria of quality have been proposed: the content of "high- temperature" form of water defined the transparency or opacity of glasses, the amount of evolved carbon monoxide connected with graphite or hydrocarbons inclusions and diffusion coefficients at temperature 800-1400°C which influence the easiness of removal of "high-temperature" forms of impurities at annealing and in initial stage of quartz melting The offered method for certification quartz raw enables one to ascertain a possible field of technological uses of quartz of new deposits without conducting industrial melting tests.
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