I have never personally encountered green corrosion on steel, only in restoration videos. I have to give you points for originality though, have not seen the tin foil trick before. You can fool some of the people some of the time but those who know, know.
Really like this grinder! 😎☕ Did a great restoring job! 👍 Really liked the drawer being hollowed out. Ambitious! But I think you should've used slotted screws instead to fasten the front so it matches the rest of the grinder!