I have a Sheaffer pen with a dual-tone #5 Feathertouch nib, and all is well with it, but there is some red staining on the top of the nib near where it enters the barrel. The rest of the nib is clean and shiny. I'm not sure what caused this staining (I got this pen like that from someone else), but I'd like to try and remove the reddish stains. The red seems to be more like ink color, toward magenta, not orange of rust or anything like that.
What products can I safely use to clean up the staining from this nib?