How to Clean Copper Coins Using Hydrogen Peroxide

1 - Disposable plastic bowl - I use an empty margarine container, - I use a harder plastic container if i put it in the microwave.
1 - Bottle of Hydrogen Peroxide which is 3% H2O2
1 - Heat Source - I have a goose neck lamp with a halogen bulb in it.
1 - Box of Cotton Swabs - Q Tips are the best - others fall apart too easily

Make sure the artifact/coin is free of any oil coating like olive oil if you previously had soaked this object. The oil coating prevents the Hydrogen Peroxide from working on the dirt.
Put object to be cleaned in disposable plastic bowl and then pour Hydrogen Peroxide on top until it is at least a half an inch above the object to be cleaned.
Using the lamp as a heater, I position the lamp to within 2-4 inches of the bowl. This heats up the solution. Be careful not to cause anything to melt from too much heat, use common sense for this part. A Heat Source is NOT necessary, but it does speed up the cleaning significantly...
note: you can use a nicrowave to heat the peroxide up first, but be careful andplease use a safe container with no metal lid on it put the coin in after the heat up in the micro wave.

f the solution is hot enough the boiling of the Peroxide should be very evident to you and should remind you of a geyser. Once it is cooking it sprays the bubbles and smokes a little also. This should continue for anywhere from one hour to two or three.
Periodically remove the object if you want to check on the progress. I usually then lay it on a napkin and take a cotton swab and start to gently rub and see how much crud is coming off the object. It might take several hours or more to get real clean. You might even have to repeat the entire process if the object has a lot of stubborn crud on it.

When the bubbling of the Peroxide stops the cleaning also is done. If it needs more cleaning start over again with fresh fluid.
Keep your cotton swabs wet with the Peroxide while gently rubbing, this will prevent scratches.
When done with your cleaning, rinse the object well with water.