Header Changing Color

i bought a chrome header a few months back and now it's turning blue-ish in color. at first i thought it was from the oil from my hands, from when i installed it, that was making it change color due to the heat or something...but the other day i read an article that said a chrome exhaust turns blue-ish if its running consistantly lean...is that true or what?

http://myspace-724.vo.llnwd.net/00217/42/70/217290724_l.jpg

It's normal, don't worry about it.

Yep, thats fine.

sweet. thanks guys!