ABSTRACT
Aluminum (Al) was discovered only in the middle of the nineteenth century, not because ores (bauxite) were not plentiful, but because its oxide was much too dif‰cult to reduce by the earlier techniques. It was initially used as a precious metal because of its high luster and resistance to dis‰guring by oxidation. Moreover, it was superbly light, which made it suitable for objets d’art, for example, opera glasses (Figure 1.1) [1-3]. It could be worked or cast more easily than gold or silver, but is not nearly as strong, although it has been improved when practical alloys were discovered.
