Originally Posted by TrekJapan

Naval Jelly is just phosphoric acid. It's been a while since I was a Corrosion Control Rep in DOD but it converts ferris oxide (rust) into ferric oxide. It's a great base for primer and paint. Another commercial product that works is called "Extend". The US Navy uses it on a lot of steel applications.

Chrome doesn't rust. In fact chrome cannot release electrons or corrode in any fashion. What you're seeing is rust coming through a thin plating of chrome. Chrome is cathodic to steel and will cause steel to rust (given the proper or rather improper environment).