This Coin Will Be Cleaned

Coin in distilled water. Soak during the day, freeze during the night.

Lovely Coin Benji!

Seems like a good idea, Let us know what the outcome is.

I generally soak for a couple days before freezing, and make sure it's completely solid before thawing.

That came out pretty darn nice!

The toning is from the crud and not the soap for sure. I guess this would be considered natural toning? because it came from the mint this way. I did not tone it, nor did any doctor.

Definitely came out very cool, a keeper.

errrror

One more thing you may want to try is still wanting to clean up the thing a little. If you have a glass coffee maker, put some distilled water in the glass container, place that coin in the water, turn on the hot plate section so the water gets warm or hot. Occationally a little heat, distilled water, glass cotainer may remove more of the junk.

That turned out quite well. Copper oxidizes slowly in air, corroding to produce a brown/red and green/blue patina. At higher temperatures the process is much faster and produces mainly black copper oxide. The oxide can be reduced by hydrogen gas, which is a moderately strong reducing agent, producing a shiny, clean copper surface. This provides a striking illustration of oxidation and reduction of a metal.

Equations for the reactions are

2 Cu(s ) + O2(g ) --> 2 CuO(s )

CuO(s ) + H2(g ) --> Cu(s ) + H2O(g )