Germanium

What it is

Germanium is a metalloid used in fibre-optic cables, infrared optics (night vision, thermal imaging), and space-grade solar cells.

Why it matters

It is a byproduct of zinc refining and coal fly-ash processing. China imposed export controls alongside gallium in 2023.

Circular challenges

Whether germanium re-enters the economy at end-of-life is mostly settled at the design stage. These are the recurring blockers.

• Locked in fibre

  Germanium-doped fibre-optic cable is buried in the ground; when replaced it is rarely processed to recover the germanium.

• Tiny doping fractions

  Concentrations in finished products are very low, so recovery only pays in defence-grade infrared optics.

• Byproduct exposure

  Supply depends on zinc demand and coal processing — both shifting unpredictably.