Apple’s iPods and MacBooks are essentially made from a piece of aluminum. The only difference is they anodize it. Bill Hammack the Engineer Guy explains this method taken from a chapter int he book Eight Amazing Engineering Stories.
Anodization is basically corrosion/rust. They take the casing for said device and corrode it until a porous honeycomb-like outer layer is formed. From there they can fill up the pores with an evenly toned paint and seal the color in by boiling the casing.
Don’t understand? (Don’t worry it took me a bit too.) Let this expert explain it.
The end result is a nice colorful thick protective casing with some scratch resistance. Imagine all the possibilities with Anodization.
Fact is, a lot of the electronics you have now contain anodized metals. It makes the metal tough and makes it get along better with glues and adhesives.