Crytur provides synthetic sapphire profiles for demanding technical applications as well as precise sapphire optics

Key properties


Sapphit™ high resistance characteristics make it ideal material for applications operating in extreme conditions such as high temperatures up to 2000°C, extremely high pressure or harsh chemical environments. Sapphit™ tubes retain their shape perfectly until melting point.

  • PURE

Sapphit™ is grown as single crystal in a strictly controlled environment. The sctrictly controlled production process allows us to chieve very high material purity over 99,995% of Al2O3. The implementation of Sapphit into clean processes is without the risk of process contamination.


Just one grade under diamond, sapphire is one of the hardest materials. Sapphit™ components are scratch-proof and extremely wear resistant.


The wall of sapphire profiles is absolutely gas tight which prevents process contamination through material leakage. Sapphit is also very resistant to attacks from aggressive gases.

  • High thermal conductivity
  • Enormous pressure resistance
  • Transparent, UV to IR transmitive
  • Electrical resistivity
  • Bio compatibility


Technical parameters

Physical properties

Crystallographic structure

Rhombohedral single crystal; R3c


3.98x103 kg.m-3 (20 °C)

Hardness by Mohs


Hardness by Knoop

1800 parallel to ,c' axis (0001)

2200 perpendicular to ,c' axis

Tensile strength

2.1x109 N.m-2 (25 °C)

Compressive strength

3.0x109 N.m-2 (25 °C)

Young's modulus of elasticity

4.6x1011 N.m-2 (25 °C)

Modulus of rupture

0.7x109 N.m-2 (25 °C)

Coefficient of friction

0.15 - against steel
Thermal properties

Melting point

2053 °C (3727 °F)

Thermal expansion

6.6x10-6 °C-1 (20-50 °C) parallel to ,c' axis

5.0x10-6 °C-1 (20-50 °C) perpendicular to ,c' axis

Thermal conductivity

42 W.m-1.K-1

Specific heat


Maximum operating temperature

2000 °C (3632 °F)

Electrical properties


1x1018 Ω.m (25 °C)

Dielectric constant

11.5 parallel to ,c' axis

9.3 perpendicular to ,c' axis (103 - 1010 Hz)

Dieletric loss tangent

3x10-5 parallel to ,c' axis

8.6x10-5 perpendicular to ,c' axis

Dielectric strenght

48x106 V.m-1 (60 Hz)

Optical properties

Index of refraction

n0 = 1.768 (Sodium D-line)

ne = 1.760

Optical transmition

0.18 - 6µm (Total transmition up to 87%)