Isotropic
Transparent,opaque,colorless,colored
Refractive index: 1.2-2.2
Electrical conductivity(Tamb): 10-6-10-18(ohm.cm)-1
Tg : 150°C-1200°C
Low thermal conductivity
Hardness: 3-15Gpa
Resistant to acids to soluble in H2O
Properties of inorganic glasses