Effect of Fe2O3 and Cr2O3 on the Processes of Pyroxene Formation in Silicate Glasses

We have investigated the processes of pyroxene formation in crystallization of glasses of the system SiO₂–Al₂O₃–CaO–MgO–Na₂O stimulated with chromium and iron oxides introduced together. It is found that sharp activation of the processes of pyroxene formation occurs in the temperature interval of thermal treatment 850–900°C. Interpretation of the absorption bands is carried out and conclusions are drawn on the structural role of the iron and aluminum ions in the process of formation of a pyroxene solid solution.