Dipping

No, dipping typically refers to using a product like E-Z-Est or Jeweluster- they are sulfuric acid/thiourea solutions used to remove toning. There are a few instances where this solution can be safely used to remove toning from a coin without impairment but anyone unskilled in its use should not attempt to use it on coins with any numismatic value. It is a delicate technique and too many collectors attempt this and end up ruining the coin, stripping off all of the luster or making a circulated coin unnaturally white