Adobe Illustrator is a vector-based program. What this means is that it operates on math-plainly speaking- and imagery is created with said math. Adobe Photoshop does not operate this way. Therefore, many find Adobe Illustrator a little more challenging. Not because you have to figure out the math, but because you have to tell the computer what you want to happen in a more deliberate way. So, why vector? Well, vector images look great at any size. They look graphically clean and file sizes can be smaller. Adobe Illustrator is just a different beast compared to Photoshop and produces different results.
The best way to create the illusion of metallic surfaces in Adobe Illustrator CS4 is to use the gradient tool with several different values. In fact, when it comes to creating metallic surfaces in Illustrator, Adobe has you covered. There is a swatch pallete designed for metal.
The following video art lesson shows you how to create the illusion of a metallic surfaces in Illustrator CS4.