I'm almost positive theres no color change, I think it would show at the edges of the chipped-rusty spots, and I have seen others this color on this site. I believe what I sent to Troy were too large of picture files, I don't know if the color would have changed in this size of file. Yes, only one vent at the bottom, this is something I didn't see myself, and after I cleaned it so well with that can of oven cleaner ( I think my Mother thought that was something that would kill you!), I'm sure there were no repair spots in the bottom of the kettle as if someone would have welded them over. Maybe this is why I thought it was just a smoker, it really doesn't get very hot with all on top vents open, you have to shake, or tap the sides to expose red embers! Again, this is so great to see these comments, thanks to all that have posted.