Removing Gum From Copper Coin?

try freezing it and see if it will flake off with your fingernail.

let me know how it works out...I know it works for getting gum out of carpet.

i once used olive oil to remove gum on my kids hair- I don't know if it works in coins

Peanut butter

just kidding

I would recommend the freezing method and go from there

Depending on the coin naturally but the best thing is to use items that would not hurt the coins. For example as already noted allowing water to run over the coins. Since you already know Acetone does not work, try Denatured Alcohol. A Martini might do the job but of course you wouldn't want to drink it.
Olive Oils have been used by some to remove such contaminates but the results could vary. This is pending the Olive Oil and the gummy substance. Some have said Vinegar works for that gummy stuff but they don't know what your gummy stuff is of course.
If it was just chewing gum you could give it to a kid and tell him to chew it off.
The methods usually become harsher as you find nothing works. The WD-40 or similar types of breakfree type oils might well dissolve that stuff.
Regardless of what your do if you should finally remove that stuff, rinse the coins in distilled water and blow dry with a hair dryer on warm setting.

I've used Goo-Gone, a toothpick, and an old cotton cloth to remove gummy substances from lower-grade copper, copper-nickel, brass, and similar foreign coins. Doesn't seem to hurt anything, although if any of you chemist types know of any residuals in Goo-Gone that might cause long-term problems with these coins, please comment. (And after I'm done for the day, I head straight for disinfectant soap to clean coin residue off my hands. I'm not the queasy type - I can fork manure all day without retching - but I can't help but wonder who has been fingering these coins after noticing how black my fingers turn!)

Does that wheatie qualify for a split grade now?

So... I had the coin in the freezer for a couple days. It chipped right off. There was some residue left over that came off with hot water. Then I stuck it in the clothes dryer to dry off. Thanks for the help everyone. Nice little experiment.

PS Only kidding about the dryer

Mike