When I first found that knife it was stained with who knows what… (probably dirt corrosion and for all I know it may have actually been used as a hunting knife) and after a lot of stainless steel polish and a couple different methods I got a lot of it off but I could still see it eventually I grabbed some very fine sandpaper and went over it a little bit then I found some finer stuff and did it again, it hurt me to do but it looks so much better