This is a really short message. Have you ever used Potassium Permanganate and gotten it on your hands and had those dark brown stains that won't go? Home Depot (and lots of other places) sells 'Super Iron Out' or plain 'Iron Out' which is a rust stain remover. Urban legend has it on good authority that this will remove potassium stains.
I just thought you might like to know.
Dr. Erik Johnson from koivet"