Germanium is a brittle and crystalline metal, with a pale silvery appearance. It has poor electrical conductivity and is most commonly used in semi conductors. When doped with arsenic, gallium or other elements it is useful as a transistor element.
Other applications include use as an alloying agent, as a phosphor in fluorescent lamps and as a catalyst. Germanium and its oxide are transparent to infrared radiation and as a result are used in infrared spectroscopes and highly sensitive infrared detectors.