http://www.post-gazette.com/pg/04237/366764.stm

The brewery has entered a partnership with Pittsburgh-based Alcoa Inc., the
world's largest aluminum maker, to produce aluminum bottles that keep beer
colder for longer, Alcoa officials said.
Alcoa and Pittsburgh Brewing today were announcing that about 20,000 cases
of the new aluminum bottle beer are being shipped out this week to many of
the 28 states where Iron City is sold.