Like Tom said, it's just tinted lacquer. Experiment on some plain scrap aluminum until you figure out the right color. There are transparent dyes available to add to clear lacquer. Then you do multiple coats of the right shade until you have tinted the aluminum the correct color.
I used the technique to tint the aluminum pannel below the viewing screen on this 15" Motorola color set. Follow the link below to my web site. Good Luck
http://antiquetvguy.com/WebPages/The...ola-16CK1.html