The orange colour is okay, it's called corona discharge, you get it where high voltage and electric conductive liquids are in close proximity, usually oil fmes is enough to do it, they get attracted to the porcelain and cause the staining, if it gets like streaky lightning looking though this is discharge through the body gap between porcelain and metal, not good need throwing away.
As to why they become loose in the body is a mystery, only ever had that once in 25+ years.