Germanium, like Gallium, was an element that confirmed the utility of the Periodic Table, as Mendeleev predicted its properties in 1869, and these were confirmed in 1886. The discoverer, Clemens Winkler, wanted to call it neptunium as the planet had also been discovered based on predictions, but that name was already in use. He settled on his newly-formed (1871) home country instead. Germanum is quite rare, being found in a few blendes and ores, but also in small quantities in coal. This is thought to be because some plants concentrate germanium and presumably so did the plants of the Carboniferous period. Germanium was critical for the first wave of semiconductors until replaced by silicon in the 1970s, but is still used for very high-performance devices such as quantum computers. Some germanium oxides are opaque to light but transparent to infra-red, so are used as windows and lenses for night vision and thermal imaging.
Sources: britannica.com, wikipedia.
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