Seki Diamonds

General Diamond Properties

Specifications and qualities of diamond



Tensile Strength

Compressive Strength

Fracture Strength

Sound Velocity


Young’s Modulus

Poisson’s Ratio

Atomic Density

Thermal Expansion Coefficient

Thermal Conductivity

Thermal Shock Parameter

Coefficient of Friction

Derbye Temperature

Optical Index of Refraction

Optical Transmissivity Range


Optical Absorption Coefficient

Loss Tangent at 40 Hz

Loss Tangent at 140 GHz

Dielectric Constant

Dielectric Strength

Electron Mobility

Hole Mobility

Electron Saturated Velocity

Hole Saturated Velocity

Work Function



10,000 kg/mm²

>1.2 Gpa

>110 Gpa

400–800 MPa at <1 mm thickness

18,000 m/sec

3.52 g/cm³

1200 GPa


1.77 x 1023 atoms/cm³

1.1–5.0 (300-1300K) ppm/K

10–20 W/cm-K

30,000,000 W/m

0.05 (dry)

2,200 K

2.41 (at 591 nm)

225 nm to far IR

0.02–0.03 at 10 microns

0.05–0.3 at 10 microns




10,000,000 V/cm

2,200 cm²/V-sec

1,600 cm²/V-sec

27,000,000 cm/sec

10,000,000 cm/sec

small and negative on [111] surface

5.45 eV

1013–1016 Ohm-cm


The many unique advantages of diamond

At 10 on the Mohs scale diamond is four times harder than corundum such as sapphire and ruby. Diamond is highly resistant to scratching and abrasion. It is also chemically inert and resistant to extremely corrosive, radioactive, high temperature environments.

Diamond’s transmission range exceeds that of all traditional IR window materials.

Optically, diamond has the widest transmission band of all known materials, from 220nm to over 50µm, covering UV, visible, infrared, terahertz, and microwave spectral ranges.

With a thermal conductivity of 2000 W/mK diamond exceeds copper by a factor of five while also being electrically insulating.

Its large electronic bandgap of 5.45 eV allows diamond to withstand high electric fields and to be used in hazardous and radiation intense environments.

High intrinsic electron and hole mobility allows electronic charges to travel through the diamond structure with relative ease, which is ideal for high-frequency electronics.

Seki Diamond Systems provides a broad selection of systems for producing synthetic diamonds and diamond films for a spectrum of applications.