Physical Properties
Density in g/cm³	2.203
Crystal Structure	Amorpheus
Bubbles / Inclusions	None
Total metallic impurities in ppm	25 - 30
OH– Content in ppm	400 - 500
Thermal Conductivity in W/(m · K)	1.38
Specific Heat Capacity in J/(Kg · K)	703
Thermal Expansion in 1/K	0.55 · 10-6
Softening Point in °C	1730
Annealing Point in °C	1180
Strain Point in °C	1075
Max. Service Temperature (continuous)	1150°C
Max. Service Temperature (limited time)	1300°C
Dielectric Constant @1kHz	a = 10
Dielectric Strength in kV/cm @20°C	250 - 400
Young’s Modulus (E) in GPa @25°C	73
Shear Modulus (G) in GPa @25°C	31
Bulk Modulus (K) in GPa @25°C	36.9
Rupture Modulus in MPa @25°C	50
Apparent Elastic Limitin MPa	55
Poisson Ratio @25°C	0.17
Compressive Strengthin GPa	1.1
Tensile Strength in MPa	50
Knoop Hardness in kg/mm²	500