cleaning up clad

[Rusted Nail]

Tried four solutions , (1)White vinegar ,(2) White vinegar with salt and tablespoon lemon juice, (3) Ammonia, (4) Peroxide . They all sat for 18 hrs. I was impressed with the vinegar, salt, lemon method

[VERDI-CHEMIST]

Your methods are fine as long as the coinage has no numismatic value. The bad thing about using acids on coins is that nearly all numismatic premium is destoryed along with the patina. In the future, if you are going to continue using the acids method, you should just use muriatic acid. It's a lot stronger and will work faster with less hassle.