Hey HG, Unfortunately I don't think nic-a-date will work on that. It may even damage it further. It is an acid, (sulphuric:huh: maybe). If it's that tough emerald green or that washed out (whitened) green, the damage may be behind the green. So if you remove it, you may only have pitting. I usually use hot hydrogen peroxide on mine and hope for the best. A brass brush w/ dish soap also works on the softer green. With the hydrogen peroxide, put some in a microwave for about 10 seconds. Watch out it may bubble over. Just get it nice 'n hot and then put the coin in it. DO NOT PUT THE COIN IN THE MICROWAVE EVER!!!!! :grin: Bad things can happen :shocked04: The minute you drop the copper in the glass (I use a shot glass so there is solution on both sides of the coin), it will bubble like crazy. I let it go for about two minutes and then hit it with the brass brush. But you must remove (with lots of soap) all previous remains of any olive oil, mineral oil or other oils, otherwise the hydrogen peroxide won't work. Here is a coin that I barely got a date off of with the green mentioned. This coin was almost brand new when dropped. With my luck, the green only killed the date, and not the rest. This coin was completely green before cleaning. So if you feel you want to try a new cleaning method, give it a try. It works on some and not on others. Good luck.
