Iv'e tried the Potato method on Metal Detected Pennies with luck . Just have to check it a couple times overnight . It actually works !!
I may have done this wrong, yes, I see where checking it during the night would have helped, but I do see where it does take a lot of junk off the coin...Maybe should have taken the 1968s out a little sooner.
I think you are right....Need more potatoes.....And an alarm clock too!.....To remind me after a few hours to pull D coins otta D po-tay-toe!!
This completely strips the coin. Not only the patina but any trace of luster. This is not an acceptable practice among numismatists. I don't even see that the coins came out looking better. They are still a mess. Better to leave well enough alone in my opinion.
I need to apologize folks! I should have said I really do not recommend cleaning coins unless they are totally messed up like the coins that started this thread. Pickin and Grinin is right with what he said. The subject of thread is how to remove the green corrosion and this method can work for that. That is why I posted this method! Hope I didn't cause anyone to make a coin worse!!
Try this on copper: put the penny in a plastic or glass receptacle and cover it with Worstershire sauce. I normally leave it overnite (less if the penny isn't a disaster). It usually comes out shiny and clean.
Please don't. The active ingredients (for this) in Worcestershire sauce are vinegar and salt, which slowly dissolve copper. It'll leave your copper coin shiny, but ruined for collectors -- the surface will be etched, and we count that as damage.
And, that is what matters. If they're important to you, then try to "preserve" them. I would experiment with different methods on the worst of them, but would certainly try to "get the green off". I wish you well, and hope you get them all cleaned.
You certainly made a " head slapper " notification there Pickin and Grinin I know I will not be doing that again. But if I should, I will certainly be keepin a very close eye on it...
Never heard of that method before.....But being a retired trucker who is half deaf because of the road noise, someone may have told me, but I didn't hear him... I will have to give that a try on a invaluable coin, Thanks for that info MIMI VEE!