I found a small group of coins and decided to illustrate how I leave the patina intact while zapping. The coins you see in the photo above left were pretty crusty. I wanted to see how much patina I could leave using electrolysis and my bamboo stick. The picture indicates the degree of success. Please feel free to ask questions and I would like feedback. If you want to learn my zapping techniques please join us at the following URL: http://groups.yahoo.com/group/coinzappers You have a standing invitation from me. Thanks you and God Bless.. Jerry..