Cleaning the gunk off coins and other cleaning tips

I know many people don't clean their coins but I have 2 coins with some black gunk on them which I'd love to remove.

Also I have some which I'd like to experiment and use some polishing compound and make them ridiculously shiny.



Here's one of the coins I'd like to clean.

Thoughts?

Looks to me like the black is the original color and the yellow is the gunk. And don't ever use a polishing compound to make the coin shiny. It will destroy the coin and render it worthless.

On this relatively low value coin use acetone or ask your wife for some nail polish remover containing acetone. Let soak and use a cotton swap to rub and hopefully remove the gunk. This may work and is safe to use without damaging the coin. I generally don't advise cleaning coins before you know all the facts but in this case I think it is safe to do so. I also agree that polishing compound on any coin will destroy the coin as far as value is concerned if any.

For cleaning without harming the coin, try an ultrasonic jewellery cleaner. They can be found quite cheap and once I removed tar when a whole side of a coin was covered in it. Absolutely safe and best used to remove ordinary dirt and things like tape residue.

Will

Only ever use pure acetone, nail varnish remover has added chemicals. Acetone can be bought at any pharmacy.

Verweis : "Offa"Acetone can be bought at any pharmacy.

​ Indeed. I got this small bottle over six years ago from a pharmacy at a low price. Still have it.
[Coin for bottle size comparison]

This coin is worth pennies. His wifes nail polish remover will be just fine.