I have a belly button piercing and the metal is stainless steel.. I was wondering does it develop rust whenever you go shower and clean it? Can I still swim in the summer with it or do I have to take it out? What happens if I swim in the pool with it?
Theoretically stainless steel is supposed to be what it's name says it is - stainless. However there are different grades of stainless so yours might dis-colour if it's low grade. Think of all the stainless steel cutlery you use to eat with - if you keep it clean it doesn't go rusty ; it can if you don't look after it.
No it won't rust. Just make sure to get the pool water out of the piercing when done at the pool. Just to avoid drying out the skin too much.