Its just like the ^above said, the heat spreaders (specially the metal once) use the process where they powder coat it with chemical/paint usually the finish is matte color (not shiny) then bake it in the oven and gives the very nice shiny color (like the one's you get from G.Skill Ripjaw's heat spreaders, they are a very thin layer and are very shiny.) They layer is really thin compared to spray painting them. The same for Anodizing
If you want a different color, the best Black/Red color Ram sticks are the one's sold by G.Skill. It has a matte(not shiny) black PCB and the heat spreader is very shiny/glossy red. This is the ram I have :
http://www.techpowerup.com/img/11-01-03/6f.jpg > Black PCB with red accents on the heatspreader.
For my case though my whole rig have blue accents, from the stock case fans with blue led and my current 770 Lightning with blue leds everywhere and my new cards I have yet to install from Gigabyte (GTX 970) also have blue naming), and my ram sticks stands out so much with its red accents .