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All quartz products of the company are made of high-purity fused silica and processed with modern ceramic technology. The product is of high purity and corrosion resistance. The main component is SiO ? not less than 99.99%, and the content of impurities (K2O, Na2O, Fe2O3) is not more than 0.10%, with high strength and high thermal shock resistance. High density, tolerant of acid and alkali, does not contaminate raw materials at high temperatures, does not crack during feeding, and can be used continuously multiple times