What is germanium?
Germanium is a semiconductor, with electrical properties between those of a metal and an insulator. It is a grayish-white element; it has a metallic luster and the same crystal structure as diamond; and it is brittle, like glass.
Why is it critical?
Germanium is an essential component of high-speed computer chips, fibre optic cables and has many applications in military applications such as night-vision devices and satellite imagery sensors.
The U.S. relies on China for over 50% of imports of germanium and germanium-containing materials. There is limited domestic production in the U.S. in Tennessee and Alaska.
How is it extracted?
Germanium is mainly a byproduct of zinc ore processing and is also extracted from fly ash in China.
On a global scale, as little as 3% of the germanium contained in zinc concentrates is recovered.
According to the USGS, more than 60% of the germanium metal used is routinely recycled as new scrap during the manufacture of most optical devices.