… Beryllium, chromium, hafnium, rhenium, thallium, cadmium, germanium, vanadium, gallium, indium and niobium …
Explanatory notes
… ‑ Beryllium, chromium, hafnium, rhenium, thallium, cadmium, germanium, vanadium, gallium, indium and niobium … protective tubes for electric heating elements, etc. (C) GERMANIUM Germanium is extracted from residues of zinc manufacture, from the ore germanite (copper germano‑sulphide) and from gasworks’ flue …