Germanium

A semiconductor element for fiber optics and infrared optics, recovered from zinc and coal.

Overview

Germanium is recovered from zinc ore processing and from certain coal ashes, with China the leading producer. It is used in fiber optic cables, infrared lenses for night vision and thermal imaging, high efficiency solar cells for satellites, and as a polymerization catalyst for PET plastic. The first transistors were made of germanium before silicon took over the semiconductor industry. Export licensing imposed by China in 2023, followed by a ban on shipments to the United States announced in December 2024, made germanium a symbol of critical mineral risk, and prices rose outside China. The market is small and opaque, with prices assessed per kilogram rather than traded on an exchange.