GLASS FORMATION, PROPERTIES AND STRUCTURE OF GLASSES IN THE P2O5-WO3-K2O-Al2O3 SYSTEM.

Glass formation in the P//2O//5-WO//3-K//2O-Al//2O//3 system was investigated and the glass-forming regions are presented. The properties of the glasses in the P//2O//5-WO//3K//2O-Al//2O//3 system (Al//2O//3 8 mol. %) are reported. The colouration of glass was studied. It was found that W**5** plus ions make glass blue. Infrared spectra were measured by means of making KBr pills. Results of the investigation suggest that P-O-P, P-O-W, and W-O-W bonds form a continuous network in phosphate glasses. We suggest that tungsten trioxide is a glass former.