I tried to clean off some tape residue off the back of a nicely toned coin I have by dipping it in acetone. It cleaned the residue however it looks like it may have darkened the original colbalt blue toning. I didn't realize acetone could impact toning, does it?
On silver or gold? No way. On copper? Maybe... keep copper coins soaking in a cool, dark place to minimize the possibility.
Acetone won't remove the toning on silver or any metal . I wouldn't use it on copper except on extreme cases , but then I probably wouldn't buy it .
No. Acetone is pretty much an inert organic solvent. It will dissolve organic debris, but will leave inorganics (and natural toning) alone.
I'm at over a thousand times with no changes in toning. From what I understand, those that have to work on MS copper have had some problems. There are risk with any coin. Once you remove the junk, the surface under it may not have toned the same as the rest of the coin. You just never know what can be hiding under tape, glue or PVC.
Or just plain old surface deposits that have accumulated on the coin over time. To answer the question, no acetone does not remove or alter toning on silver or gold. And sometimes it doesn't even affect copper coins, but copper is a crap shoot. That said, the things that acetone does remove, by being removed, can affect the overall look of the coin. And that is true with any coin.
The only danger I could see would not be from the acetone, but what happens after the acetone removes the organic compounds. Lets talk about a red cent. Maybe there is an organic layer on an otherwise red cent. Lets place in acetone and remove this layer. Now, once the coin comes OUT of the acetone, the surfaces now have a chance to react to the environment more freely. That would be the only danger I could see, that by cleaning the surfaces you are now allowing the metal to once again try to tone. Also, I agree with Doug on copper. Copper is always troubling since it has the most complex color variations. removing a layer of something from its surface can do quite a few different things to the perceived color. I do not think the acetone changed the toning, but the perceived color can be changed by removing some non-toning from the surface.
i agree that toned copper is a crap shoot with acetone ... it you have toned copper and love the look of the toning, I wouldnt mess with it.
No it doesn't but there may have been a thin film of something over the cobalt blue toning which is now gone and that may be resulting in a different appearance.
That must be what happened, because it clearly darkened once I dropped it into the acetone. Next time I'll just use Paddy54's approach. Thanks everyone.
Could have had some pvc crud on it and changed to darker shade after coating was gone. I'm red-green color blind so no expert but CAN see thru most camoflage patterns....
