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 Replies: 18 / Views: 17,900 |
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Valued Member
United States
360 Posts |
I've never dipped a coin in acetone before, so I could use some help. I want to get the crud off of this coin without scratching it up any more than it already is.  It appears that there was a piece of packaging or masking tape on this coin at one time. The tape was removed but some of the glue is still stuck to the coin. My main question is: How long do you keep the coin submerged in acetone? I've heard of coins being "overdipped" a few times on this board. Does that mean the coin was immersed for too long in the acetone, or the coin has been dipped numerous times? Thanks!  |
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Moderator
 United States
23522 Posts |
Acetone and "dip" have nothing to do with each other; you could leave this coin in acetone essentially forever without harming it. I'm about to clock in, posting from my phone, so I can't get verbose but this coin looks like a pretty good candidate for help from acetone. We discuss it frequently; you might want to search this subforum
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Bedrock of the Community
United States
12437 Posts |
Traditionally, "dipping" refers to the use of a commercial coin cleaner such as Jeweluster or E-Z-Est. Coins are "dipped" in a thiourea and sulfuric acid solution to remove toning but overexposure will also damage luster.
Let your coin soak in acetone for 5-10 minutes and check the progress. If the adhesive has been completely removed, rinse your coin with fresh acetone and let it dry. If adhesive is still present, you can soak longer. Some persistent adhesive may need a light dabbing with a q-tip(wet coin + wet q-tip) for complete removal.
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Valued Member
 United States
360 Posts |
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Acetone and "dip" have nothing to do with each other... See...I learn something new here everyday!  Well, I apparently do not know what "dip" means yet, but thanks for letting me know that there's a difference! I'm gonna give this one a bath tomorrow. |
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Valued Member
United States
360 Posts |
Quote:
Traditionally, "dipping" refers to the use of a commercial coin cleaner such as Jeweluster or E-Z-Est. Coins are "dipped" in a thiourea and sulfuric acid solution to remove toning but overexposure will also damage luster. BAM! Just like that, it's been all cleared up for me! Thank you!  |
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Pillar of the Community
United Kingdom
4208 Posts |
Copper can photocatalyse acetone into acetic acid in the presence of light. So do it in a shielded place or leave it in the dark. Even the copper in a silver piece can do this. It ends up turning to verdigris when reacting with copper (copper Acetate). If you live in an old enough house, you might have lead glass windows which filter some of the UV out and this would make it less of an issue.
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Bedrock of the Community
United States
20753 Posts |
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Copper can photocatalyse acetone into acetic acid in the presence of light. So do it in a shielded place or leave it in the dark. Even the copper in a silver piece can do this. There was a typical article on the internet about this with excessive scientific explanations. So just to satisfy curiousity I tried it over and over and over. I put Copper coins in Acetone outside in the Sun. Then on window sills inside in the Sun. Then in the Dark. Usually left for weeks in each. I finally figured out I was usin the wrong SUN. Nothing happened. As to using Acetone, best read lots of posts here by using the SEARCH tab and trying Acetone, coin cleaning, cleaning coins, etc. Important things to remember is try to use Glass utinsils if possible to place the coins in a glass jar. Remember that using your fingers is safe for your fingers but the Acetone could remove dirt from your fingers and add it to the solution. Do not use metal tongs if possible for the same reason and metal could scratch your coins. Always test your Acetone for purity by placing some on a CLEAN glass dish and allowing to evaporate. Nothing should be left if pure. Length of time for a coin in Acetone is good for a few minutes. Additional time is of little use. |
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Pillar of the Community
 United States
2448 Posts |
 OK, do I have to send my coins to the ISS or NORAD for dipping or not? I've used acetone before with less than stellar results. That is, the old Morgan did not loose any of it's tarnish nor the embedded dirt in devises. The only way I removed the dirt was with a tooth pick and Q-tip softy manipulating the acetone into the device. It won't make me a bad person will it? |
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Valued Member
United States
360 Posts |
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It won't make me a bad person will it? I know people who know people. Torquemada, send the coin to me and I'll have it shipped directly to the Baikonur Cosmodrome for the next flight up to the ISS.   Anyway, success! I gave her a little bath and used Q-tips as suggested. Thank you all for providing me with information, much appreciated. The only issue I have is the glue that was covering the middle section of the coin was protecting the silver, so that portion of the coin didn't tone at the same rate as the exposed portion. The acetone bath resulted in a two toned coin.  You can clearly see the line across the neck where the piece of tape used to be. That's okay as this isn't exactly the greatest example of a Barber half. Now that I know what I need to do, I'll repeat the process with some of my dirtier coins. Thanks again! |
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Pillar of the Community
United States
1314 Posts |
 What works for me. (Left to right.) Acetone. 100% pure from Walgreens â€" used as nail polish remover. (And provides me with the opportunity to flirt with the girls at the cosmetic counter while claiming a legitimate excuse.) I think 16 oz. was about $3. A secondary container. Needn't be cork stopped glass. It does need to be a receptacle for used acetone. Any chemist knows that you do not contaminate the pure source by dumping the used portions back in the original container. Tapered glass cleaning vessels. A juice glass works well for silver dollars and halves. A shot glass is perfect for quarters and smaller. Tapered vessels touch the coin only by its rim. Goodwill has them for less than $1 each. Small funnel. After I put the coin in a glass cleaning container, I pour enough Acetone from the secondary container to just cover the coin. Accounting for evaporation, you may need to add from the original container. Covering the glass container with the funnel, reduces acetone evaporation. Periodically swirl the vessel to remove debris from the coin. When clean, open secondary container, insert funnel, pour acetone and coin from cleaning vessel into secondary container. Coin remains in the funnel. Transport to Kitchen sink for hot water bath. When coin is quite warm, give it a final rinse with distilled water. Coin can be air dried with a hair drier, and you have not handled it very much, except by the rim. Total cost is usually less than $5 to start, and 16 oz. of acetone will do many coins. Total time is less than 5 minutes for most coins. Bear in mind that I am new to this, and can't wait to learn what others are doing. |
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Bedrock of the Community
United States
10038 Posts |
I buy the acetone at Walmart for 1.85  I pour enough acetone to cover the coin into one of these... an old glass furniture coaster (5 cents at a a garage sale):  I place an edge of the coin down into the acetone and use the "leg" of a cap from a Bic pen:  to lower it all the way (so as not to splash the acetone). I then put the plastic top I saved/cleaned from a peanut butter jar - like the in the pic below:  over the coaster/coin combo (limit evaporation). After a few seconds I use the Bic cap again to get under one edge of the coin and lift. I use a pair of plastic coin tongs (inexpensive from Wizard supply):  and transfer the coin to a clean cotton cloth (OK - clean white T-shirt!). I wait around 3 seconds to guarantee all the acetone has evaporated (overkill I am sure), then use my hand under the T-shirt to position the coin in the 2X2 where I want it. The first acetone bottle I emptied is now my receptacle for used acetone so I do not contaminate my "good stuff." Used acetone is implemented for an initial bath on a heavily dirtied coin. How much squash could a Sasquatch squash if a Sasquatch would squash squash? Download and read: Grading the graders Costly TPG ineptitude and No FG Kennedy halveshttps://ln5.sync.com/dl/7ca91bdd0/w...i3b-rbj9fir2Edited by Earle42
09/28/2013 7:06 pm
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Moderator
United States
23522 Posts |
That glass coaster is a *great* idea, Earle42. Do you find it in any way limits the ability of the acetone to get under the coin? I've always used a jigger or shot glass where the coin can't sit flat for just that reason, but I may just be paranoid.
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Bedrock of the Community
United States
10038 Posts |
Thanks SsuperDdave I have not seen where it limits the REV from getting enough acetone. Initially I had wondered, but after a year of this it seems to work just fine. The back and front end up with the same effect on them from the acetone. I also like the idea that I am giving a real purpose to an actual piece of antique depression glass - even though its worth very little monetarily. But I also collect antique glass insulators so I have a soft spot for old glass anyway . Oh... I have also used the glass lid off of antique canning jars. Not the majority, but some, styles of these actually will sit flat when upside down. Just keep an eye out at garage sales etc.. Despite what a lot of people think, most are not rare and certainly and likely can be had for .25 (or in free boxes!). How much squash could a Sasquatch squash if a Sasquatch would squash squash? Download and read: Grading the graders Costly TPG ineptitude and No FG Kennedy halveshttps://ln5.sync.com/dl/7ca91bdd0/w...i3b-rbj9fir2Edited by Earle42
09/28/2013 8:16 pm
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Moderator
United States
23522 Posts |
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I have not seen where it limits the REV from getting enough acetone. Initially I had wondered, but after a year of this it seems to work just fine. The back and front end up with the same effect on them from the acetone. That's good to know, and as a result I'm going to put stuff like it on my "recommendation" list. |
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Bedrock of the Community
United States
10038 Posts |
I'm glad this could help... and honored!
How much squash could a Sasquatch squash if a Sasquatch would squash squash? Download and read: Grading the graders Costly TPG ineptitude and No FG Kennedy halveshttps://ln5.sync.com/dl/7ca91bdd0/w...i3b-rbj9fir2 |
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Pillar of the Community
United States
1314 Posts |
My mission in life is to propose my mediocre idea, and let the experts show better. It works, and we all gain. Win/Win. Thanks all.
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Replies: 18 / Views: 17,900 |
Posted 09/24/2013 6:58 pm
