Detecto - your actions on this forum and eBay are what is giving you a bad reputation. If your reputation is in tatters, you have only yourself to blame. Just my 2¢
YUP! At least half of the pennies that I've found since I've been detecting have been like that or worse. I've got plenty I can send to other CT members if you want your own example of this numismatic...err...oddity
Speaking of Zincolns, you can have a little fun with them by scraping the copper off the edge and allowing the cent to soak in a low acid solution (lemon juice or vinegar will do) for a few months. The zinc will dissolve, leaving two incredibly thin pieces of copper with the obverse and reverse designs undamaged.
No, it's not done by someone with something. This a rot nothing more. The outer layers of copper overhang the inner core of zinc.