As a extremely high-purity IR material, Germanium is involved in wide-ranging applications from semiconductors and infrared lens components to  fiber optics and LEDs.


Relative Cost of Material


Machining Degree of Difficulty


As one of the highest-purity materials available commercially, Germanium is a versatile materials that is sought out for both its IR and semiconducting qualities. It is similar to silicon in machinability, and can be polished and shaped into tight-tolerance and complex shapes using a slight modification of standard optical material machining techniques. Germanium is not cheap, however, so the pricing on germanium components is often driven by both raw material cost and the scrap rate and skill with which the component manufacturer has with the material. 

As with many other technical materials, Mindrum Precision has been grinding, polishing, and machining components out of germanium for decades, and our competence with this material translates to in-spec components and better pricing for our customers. Click here for our contact information or to request a quote, and we will show you why so many designers and engineers have trusted us with their mission-critical needs.


Germanium is extremely popular in the semiconductor industry, and it (along with silicon) is found in transistors and many other electronic applications. Germanium’s high refractive index has also made it a frequent choice in optics, where it is used in both standard and infrared optical applications in the form of wide-angle lens and night-vision applications as well as in microscopy. Lastly, its conductive properties have made it an essential staple in the fiber optic industry, with germanium fiber optic cores becoming in increasingly high demand. 


Material PropertyGermanium
Density (g/cm^3)5.32
Hardness (Knoop)780
Tensile Strength (MPa)140
Modulus of Elasticity (GPa)130
Compressive Strength (MPa)2200
Poisson's Ratio0.3
Dielectric Constant (@1MHz)16.2
Coefficient of Thermal Expansion (1 x 10^-6/°C)6.1
Thermal Conductivity (W/m K)64
Specific Heat (J/kg*K)315
*Note: Properties vary by manufacturer. The above information should be used for general reference purposes only.

related Materials

  • Silicon – A similar material, used in both IR and semiconductor applications
  • Fused Silica – High-purity optical material with excellent mechanical properties
  • ULE Glass – Near-zero CTE glass, with good optical qualities