Crystallization of lithium trisilicate, Li2Si3O7, from Li2O|SiO2 melts

Li2O-SiO2 melts containing 25 mole % Li2O can be crystallized at ∼890°C to give Li2Si3O7 as the principal crystalline product. Crystallographic, optical and I. R. data are given for this new lithium silicate. Li2Si3O7 is thermodynamically metastable. Li2O-SiO2 melts or glasses which have undergone amorphous phase separation prior to crystallization give greatly reduced yields of the trisilicate.