Specific physical and chemical properties are as follows:
Silicon content: more than 80%
Strain temperature: 520 ℃
Annealing temperature: 560 ℃
Softening temperature: 820 ℃
Refractive index: 1.47
Transparency (2mm): 92%
Elastic modulus: 67KNmm-2
Tensile strength: 40-120 Nmm-2
Stress optical constants of glass: 3.8xl0-6mm2/N
Processing temperature (104dpas): 1220 ℃
Linear Expansion Coefficient: (20-300 ℃) 3.3 x 10-6K-1
Density: 2.23 GCM-1 (20 ℃)
Specific heat: 0.9Jg-1K-1
Thermal conductivity: 1.2Wm-1K-1
Water Resistance: (ISO 719) Level 1