If I decide to clean a copper coin ---- I cut one of those red solo cups in half, break a toothpick in half and place at bottom, put coin on top of toothpick and pour in a few ounces of Hydrogen peroxide, let it sit and fizz for a few hours, dump and replenish with new hydrogen peroxide, let it sit and fizz over nite. By the next morning most of the crud should come off fairly easily. The coin will be really dry, work some vaseline over it between your thumb and forefinger, this will release more of the dirt. Then clean off vaseline with a paper towel. DO NOT USE THIS METHOD ON COPPER COINS OF VALUE! I did not use this method on the King George II, or the 1797 draped bust, I did use it on the injuns and the druid, the 1845 large cent actually came out of the ground like that, I just brushed off the dirt with a soft toothbrush, it was probably in mint state when it was dropped and the soil was kind. It's a personal judgement call on if I clean something or not. I've been considering trying an ultrasonic cleaner on coins with little or no value.
The pics below are from a post i had a couple of years ago showing a large cent before and after the method i described above, keep in mind that if the coin is in bad shape to begin with a peroxide bath won't bring it back to life, it's just a less harsh way to clean the coin rather than a dremel, wire brush etc. Keep in mind it will turn the coin to a chocolate brown color in most cases.
Edited 2 time(s). Last edit at 01/20/2012 12:17AM by The Fog.
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