Density, g/cm³ (20°C)

2.635 – 2.660

Solubility, in water

insoluble

Type of Material

trigonal, point group 32,
a = 4.9138 Å,
c = 5.4052 Å

Melting Temperature, °C

1467

Thermal Conductivity, W/(m · K) at – 253 °C  parallel C-axis:

720.0

Thermal Conductivity, W/(m · K) at – 253 °C  perpendicular C-axis:

370.0

Thermal Conductivity, W/(m · K) at – 79 °C parallel C-axis:

20.0

Thermal Conductivity, W/(m · K) at – 79 °C perpendicular C-axis:

10.0

Thermal Conductivity, W/(m · K) at 50 °C parallel C-axis:

10.7

Thermal Conductivity, W/(m · K) at 50 °C perpendicular C-axis:

6.2

Thermal Expansion, 1/°C at 0 to – 20 °C parallel C-axis:

7.64 x 10-6

Thermal Expansion, 1/°C at 0 to – 20 °C perpendicular C-axis:

14.00 x 10-6

Mohs Hardness, indenter load 500g

740

Specific Heat Capacity, J/(kg · K) at 10 °C

744

Dielectric Constant, for 3 x 10⁷ Hz at 52 °C parallel C-axis:

4.34

Dielectric Constant, for 3 x 10⁷ Hz at 52 °C perpendicular C-axis:

4.27

Young’s Modulus, GPa parallel C-axis:

76.5

Young’s Modulus, GPa perpendicular C-axis:

97.2

Shear Modulus (G), GPa

31.14

Bulk Modulus (K), GPa

36.4

Elastic Coefficient, GPa

C₁₁ = 86.6
C₁₂ = 6.7
C₁₃ = 12.4
C₁₄ = 17.8
C₃₃ = 106.4
C₄₄ = 58.0

Debye Temperature, °C

197

Rupture Modulus, MPa

41

Knoop Hardness, kg/mm²

741