I know there there are countless articles, videos and info about this but I would like to share an observation about removing volatile organic compounds which can be deposited on the surface of a coin during the off-gassing of polyvinyl chloride. I may have missed this somewhere along the line during others presentations of how to deal with PVC residue. I recently acquired 2 proof Jefferson nickels which obviously had PVC residue but I was able to get them at a fair price and did so confidently knowing that PVC deposits can be removed with the use of acetone. There are many demonstrations showing this process and I have found most of these demonstrations do not follow through on the complete removal of the voc's. I believe I was very successful at removing all of the deposits on both of these coins. But this came with a learning curve. I had followed the common method of soaking the coin for about 30 seconds to a minute. I was initially not happy at all with the result. I proceeded to soak the coin and use a Q-tip to roll the surface to agitate the residue followed by another rinse of acetone. What I immediately noticed was the contamination was not gone but had moved around the coin. My reasoning led me to believe that although the acetone dissolved the solids, after removing the coin the acetone quickly evaporates and leaves the solids re-deposited on the surface of the coin. I did this several times and several times the PVC deposits would appear in another place and sometimes even worse. So it appeared to me although the acetone dissolves the compounds it also becomes quickly contaminated with them. This led me to one final step which I believe is key in completely removing the contamination. Immediately after removing the coin from acetone as it is still wet with acetone and before the acetone can evaporate and redeposit the contamination, I placed the coin in a very soapy solution of water and rinsed it. My first results were dramatic. Almost all of the contamination had gone. I repeated this two more times with spectacular results. I did my best to illustrate the difference below.
So, acetone huh . I also hear DO NOT use finger nail polish. Only straight purchased at a Home Improvement store . How is it on older Coppers like Colonials and IH's ? Thank You !
Yes pure acetone. It's a well known method of removing PVC contamination. I believe is safe for all coins but the method of use should be followed strictly to avoid damage. I am not a professional. I am only making observations.
Do you have to wear gloves and mask ? They won't hurt Large cents or Colonials . I have some real bad Coppers,. Maybe test it out on them first .
I fixed it for you. Using fingernail polish would ruin a coin. LOL The nail polish remover in stores some times has oils added to reduce harshness to the cuticles, so you should use 100% acetone.
There are knowledgeable people here who swear that they've seen acetone discolor copper coins. There are other knowledgeable people here who swear that's not possible (except under certain contrived conditions), and that those coins must have had some other deposit that the acetone removed, exposing the undesirable color underneath. I wouldn't use gloves when working with acetone, partly because I'd be afraid the acetone might dissolve something out of the gloves and leave it on the coins, and partly because I'm not scared of acetone. (It dries your skin, it catches fire easily, it will knock you out if you breathe too much of it, it will kill you if you breathe or drink or bathe in way too much of it.)
I wouldn't use gloves when working with acetone, partly because I'd be afraid the acetone might dissolve something out of the gloves and leave it on the coins, and partly because I'm not scared of acetone. (It dries your skin, it catches fire easily, it will knock you out if you breathe too much of it, it will kill you if you breathe or drink or bathe in way too much of it.) Oh Boy, The Boss ( AKA "The Wife" ) won't like that. LOL
Yes try to avoid contact with acetone and use in a well ventilated area. Do not use gloves they will melt. I use wooden tools like toothpicks and tongue depressors to manipulate the coin, and I touch it only briefly to rinse it.
Most of the damage when removing PVC (that has not etched the surface yet) is done with the Q-tip or drying the coin. jeffB, posted: "There are knowledgeable people here who swear that they've seen acetone discolor copper coins. There are other knowledgeable people here who swear that's not possible (except under certain contrived conditions), and that those coins must have had some other deposit that the acetone removed, exposing the undesirable color underneath." AFAIK there is no way to tell if a copper coin will turn blue or not when acetone is applied. Some turn and some don't. As for those knowledgeable copper specialists who believe that when the acetone removes a surface substance it reveals the blue color of the underlying surface...SELF EDIT. Just to be very clear: Acetone may change the color of a copper coin or it may not. If the color is changed, it can be easily reversed.
That's alright . I have a bunch of very worn Coppers ( mostly King George 2nd ) . I'll post results at a later date .
I've seen it under certain circumstances and I believe there may be a kind of toning that acetone can remove. But toning IMO is damage anyway. I've had discussions here about oxidation and came to believe that only a coin that is similar to the day it was made is concrete. I think toning is going to be an educated opinion at this point. I am not condemning toned coins but they are easily made artificially and it goes very deep.
Like I said. You must adhere to the procedure of removing voc's from a coin. I did not suggest that using a Qtip or patting dry your coin is necessary. My observation suggested that rinsing in a soapy solution has not let the dissolved solids reconstitute on to the surface. That is all I claimed.[/QUOTE][/QUOTE]
This is the only scientific paper that I have seen that says there is a reaction between acetone and copper https://www.stonybrook.edu/vescalab/research/research7.html They found if copper is exposed to acetone, acetic acid (same stuff in vinegar) can form which, in turn can form copper acetate crystals This can occur if all of the following conditions are met 1) exposed to light, 2) exposed to water vapor, 3) the acetone completely evaporates, 4) total exposure time was 18 hours. I use short soaks of 5-10 minutes max, and rinse with water (distilled if I have it) immediately afterwards, and have never had an issue using acetone to remove PVC plasticizer residue from copper. If anybody has any additional references that indicate acetone is bad for copper, please post them.
I prefer Methylene chloride, lab grade. You can't purchase high-grace Acetone from a hardware store, so it contains other residual chemicals, as well as the issues with copper coins. MeCl2 by soaking and rolling a Q-tip over the coins doesn't produce color changes - even with copper.
