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 Replies: 52 / Views: 14,148 |
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Pillar of the Community
United States
2272 Posts |
Acetone is available in hardwares but I've been told that this is not very pure and will have contaminants. Usually I'll just soak things in this acetone and rinse them off in 91% pure isopropyl alcohol. This is available at any drug store. On circulated coins they'll look better afterward if you rub a little body oil onto them after cleaning. Don't ever do this with proofs or unc coins.
Hydrogen peroxide will dissolve or loosen protein based dirts. This is not normally a large constituent part of the dirt on a coin so it won't be any more effective than water. A few coins with globs on them might be more easily cleaned with peroxide though. This can also be bought at the drugstore.
Time don't fly, it bounds and leaps.
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Pillar of the Community
United States
2272 Posts |
Oh, and I would avoid using amonia and nail polish remover. Most of the removers have small amounts of oil and fragrances added to them. They probably won't hurt the coin if you rinse it off but why take a chance?
Time don't fly, it bounds and leaps.
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Pillar of the Community
United States
1840 Posts |
quote:
Anyone ever try or know if hydrogen peroxide is any good for cleaning off coins? Mainly just dirt or other junk.
Hydrogen peroxide is a very unstable molecule that is also a very powerful oxidizing agent. In high concentrations it is corrosive. While inorganic chemistry is not my specialty, I would assume you could do a lot of irreversible damage to your coins with hydrogen peroxide. |
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Moderator
 United States
23522 Posts |
I would beg to differ with the previous comment about mixing acetone and water; they are eminently miscible. In fact, acetone is sometimes used as a drying agent for its ability to intermix with water and evaporate quickly, leaving no spotting behind. Furthermore, unless you're using distilled water, you might be better off not even rinsing a dip in pure acetone, because the water is more likely to leave something behind than the acetone is.
Having said that, you should rinse any short acetone dips because whatever the acetone removed remains in suspension. You could end up redepositing the plasticizer right back onto the coin. Done best, an acetone dip is a staged uperation, with multiple dips into clean acetone each time.
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Pillar of the Community
Belgium
2078 Posts |
Sometimes acetone will leave a bluish shine upon drying on gold proofs Then I use window cleaner spray ( you know the kind you clean windows without leaving streaks )That is a soap with a surface tension reducers and an evaporator After that I use distilled water This will remove all the grease (acetone) and all traces of impurity I pay only 2 dollar a liter for pure acetone so that is no problem whatsoever  |
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Pillar of the Community
Belgium
2078 Posts |
Ok the word I was looking for was surfactant This coin was freed from fingerprints and blue shine that way Image:  50 000 Won 1987 K.jpg47.61 KB  |
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Bedrock of the Community
United States
20753 Posts |
quote:
Originally posted by ageka
Sometimes acetone will leave a bluish shine upon drying on gold proofs
Then I use window cleaner spray ( you know the kind you clean windows without leaving streaks )That is a soap with a surface tension reducers and an evaporator
After that I use distilled water
This will remove all the grease (acetone) and all traces of impurity
I pay only 2 dollar a liter for pure acetone so that is no problem whatsoever
Great idea. I would not use the window cleaner though. Just a good rince in distilled water and blow dry with a hair dryer. And yes I do stand corrected. Acetone and water do mix. both are covalent and mix rather well. I'm getting old and forgetful. Also, most modern nail polish removers are a form of Acetone and water with numerous Dimethyl com;ounds added. Some also contain glycerin and a gelatin to soften nails so this would absolutely make this substance non usable for cleaning a coin. Regarless of what you use always wear safety glasses, do it in a well ventilated area or outdoors, keep a garden hose handy, wear hospital type plastic gloves and don't breath any gases released from your experiments. |
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Pillar of the Community
Belgium
2078 Posts |
They say familiarity breeds contempt I still remember the faces of the lab people when as a 24 year old Univ chem engineer I walked into their labo with half a litre of pure acrylonitrile in a plastic vessel with an ill fitting top wanting a glc impurity analysis The acrylo running over my bare hands I am only afraid of pure chlorine gas, pure H2S gas and explosions Though I will treat fuming nitric acid and liquid nitrogen with all repect due I never tried it but I suppose putting a coin in pure liquid nitrogen probably would clean anything off  I saw a warning movie in which they put a piece of meat into the liquid and then shattered it with a slight tap of an hammer |
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Pillar of the Community
United States
830 Posts |
Wow. I've not seen so many differing ideas on "cleaning" in a long time. I do NOT hold myself out as an "expert" on the subject, but I can relate what I have learned, sometimes the hard way, if you know what I mean. First, never use ammonia for just about all of the reasons stated previously. Ammonia is very nasty stuff. Second, acetone or a product called Xylol (xylene is the generic name) will remove PVC from any coin's surface (gold, silver, copper, nickel) and will not damage the metal. These will NOT repair PVC damage nor will they remove verdigris (that hard green crud you sometimes find). I have heard of a few folks who claim that acetone or xylene discolors copper coins. I have never had that happen, and I have used xylene to remove gunk from US Large Cents on many occasions. Third, using acetone or xylene will only remove dirt and "biologicals" (oils from handling, residue from pollution) or PVC "film". It will not remove carbon spots, old fingerprints, "staining", discolorations or natural toning. Fourth, never use hydrogen peroxide. It can damage the delicate metal surfaces of proofs or MS coins, but I don't remember exactly why or how this happens. Fifth, and probably most important, IMHO, ALWAYS use a "stepped" process for cleaning the coins. Example: Take a PVC coated coin, dip in either acetone or xylene for a few minutes, remove and rinse with DISTILLED water (not tap water as it usually contains contaminants), dip or rinse the coin again with fresh acetone or xylene, and examine the surface of the coin when dry. It should be free of the contaminants. If not, repeat the process, but don't use the same bowl of acetone or xylene more than once. You could re-introduce contaminants to the next coin's surface if you do. I hope this stuff helps. |
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Valued Member
Canada
96 Posts |
Try acetone or alcohol..100% alcohol..it prety cheap. I have a coin cleaning tips on my site if you wanna check it out..but it deals mainly in ancient coins. Also I tried something new(not on my site yet) I went and bought a UltraSound cleaner..a professional one(around 50$)..and I found it quiet effective on ancient coins...sticky soil just started to fall off...in the first few minutes....it was incredible.But on Antoninianus..one has to be carefull...it's powerfull enough to rmove the patina too.You just need to keep your eyes on these coins while cleaning them The one I have gives 42000 pulse per second...and it has a 3 minute time..so when you hit start...it stops 3 minutes later automatically.
UltraSound cleaners are usually used by jewellers.They drop their gold and silver bracelets/rings..etc in(water)..and few minutes later....they come out sparkling.
But I think acetone should do the trick for you.And I do not recommand that you drop your coin in..just put some on a dry tissue..then rub your coin. How to get pure acetone?...ask around..see where labs get theirs .
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Valued Member
Canada
96 Posts |
ooops...sorry..i didn't notice there was more then one page to this topic..and that you've already cleaned I thingee :)
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Bedrock of the Community
United States
12437 Posts |
quote:
Originally posted by ageka
I never tried it but I suppose putting a coin in pure liquid nitrogen probably would clean anything off
Hmm, I might have to take a few of my grungy coins to my lab and try this out as I have a 230L tank of LN2 there  |
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Pillar of the Community
Australia
1360 Posts |
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Pillar of the Community
Belgium
2078 Posts |
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New Member
Netherlands
8 Posts |
If you don't know what your doing and with what it's better not to clean coins as the value of the coin can be much lower also if not done right.
A brown or even black colored coin has more collecting value for most collectors and it's good to know this especially if you are intending to sell the coin.
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Replies: 52 / Views: 14,148 |
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Posted 09/19/2006 2:43 pm
