Aluminium Alloys
Aluminium is alloyed with many metals, but the most important are those with copper. Lange & Sons have obtained a patent in the United States for an alloy consisting of ninety-five parts of aluminium and five of copper, which is malleable and is used for clock springs. An alloy of ten parts of aluminium and ninety of copper is hard but nevertheless ductile. It takes a high polish and somewhat resembles gold.