The next iPhone may have a metal casing rather than the fortified glass shell of the iPhone 4/4S. But not just any metal shell, if one rumor pans out. Korean news site ETnews reported in April that Apple would use a new alloy called Liquidmetal, an exotic blend of zirconium, titanium, nickel, copper, and other materials. Liquidmetal is tough stuff--more than twice as strong as titanium, its manufacturer boasts--and can be molded into intricate designs.
Recent photographic evidence strongly suggests the new iPhone will indeed have a metal back plate, albeit one made of aluminum.