Large natural crystals of fluorides, such as calcium difluoride,
titanium tetrafluoride, zirconium tetrafluoride, are extremely useful
in optical instruments of various forms. Uranium appears as uranium
hexafluoride, all ready for the diffusion process. Compounds of such
non-metals as boron are obtainable from the atmosphere in high purity
with very little trouble. All metallurgy must be electrical. There are
considerable deposits of beryllium, and they occur in high
concentration in its ores.