Cast Aluminum Ice Bucket is Rusting

I have a cast aluminum ice bucket with a plastic inner liner that condensates. After sitting in a small pool of water for two weeks that aluminum on the exterior/bottom has started to rust. How is this possible, as aluminum is not supposed to rust?

Aluminum does deteriorate, but it's not the red rust that you see on steel. It's called white rust or oxidization. If you have red rust, it could either be the alloy mix when the pot was cast or it could be coming from something that the pot is sitting on. You might be able to just wipe it right off. Either way it sounds like you might want to clean it real good and spray paint the bottom with something to give it a moisture barrier.

I have discovered that the reason my aluminum ice bucket rusted, is due to the fact that the subject was a prototype that was cast out of a mixture of aluminum and other metals ... case closed.