In situ high-temperature Raman spectra are presented below and above the glass transition temperature (Tg) of the 0.5Na2O·0.5Fe2O3·3SiO2 (Fe-albite, NFSO), 1.5Na20·0.5Fe2O3·3SiO2 (NFS2), K2O·0.5Fe2O3·3SiO2 (KFS), and reduced K2O·FeO·3SiO2 (KFS-R) compositions. For the...