What should I do to clean gold and silver coins without damaging them and lowering their value?

DeutscherGeist

Hello Coin collectors,

I came over from the sportscard board, but I do collect coins too. What is the best way to clean coins? I know there are wrong ways and a few right ways. I do not want to damage them or risk lowering their value.

Correct me if I am wrong, but using some denatured alcohol with a 100% cotton cloth should do the trick. It will get fingerprint resisdue off and even some dirt. That would be good enough. I know it is not good to use silver polish or using a shirt to polish it.

Can I get 100% cotton cloth from a optometry practice. The cloth that is used to clean glasses could also be used for gold and silver since it is not abrasive. Is this correct?

Where can I get denatured alcohol? How about using acetone or finger nail polish remover?

The coins I am talking about are: Germany 10 Euro commemorative coins in brilliant uncirculated condition(silver), Germany 1871-1945 various silver coins in circulated condition, USA Washington quarters that have silver content 1960's, Gold coins from Persia--the Pahlavi, British sovereign, American Eagle....

Using the wrong material will leave scratches on the coin, although microscopic, it is sure to bring the value down. This is why it is best for amateurs to just not clean the coins. LEAVE IT ALONE is the best advice. I am ready to learn.

I see some beginners take their gold coin and shine it up with their shirt. A shirt might be 100% cotton, if so, I would venture to guess that no harm done. However, if some polyester is mixed into the cotton, then the coin could be held to a microscope and show light scratches from the shirt shining, thus lowering the value.

Coins that have that special polished luster (in German we call it "polierte platte") should never be touched and such coins are encapsulated anyway.


Any advice and insight is greatly appreciated!!

Blackhawk

What ever you do, don't rub on the coins surface with anything, no matter how soft. The hairlines that result can be seen when the coin is tilted in bright light and they will decrease the value as well as the eye appeal of the coin. If the coin has grease or a greenish tint to it (usually caused by PVC contamination), you can soak it in pure acetone, which is available in hardware stores, for a few minutes to dissolve the problem. When the coin is removed from the acetone, the remainder of the liquid will quickly evaporate from it's surface. Acetone is flammable and the vapors can be toxic at high concentrations, so always work with it in a well ventilated area away from flames, etc.. Also use a glass bowl as a container when soaking the coin...the acetone may dissolve a plastic one.

spoon

What Blackhawk said. Never rub no matter how soft the material. I wouldn't use alcohol or nail polish as they may have impurities. Your best bet in most cases will be pure acetone (available at hardware stores). Like BH said, it is good for lingering PVC and recent fingerprints. For old coins with dirt caked on soaking them in olive oil long term will usually break up the mess.

This topic has been discussed here quite a bit. A search of "acetone" or "olive oil" should bring up all the relevant threads.

DeutscherGeist

Thanks guys for coming to my aid. I will look at the other threads on this topic as well.

There is so much I am learning right now. I have made huge plunders in the past. I actually used silver polish to clean a German silver coin from the 1930's---what a mistake! Luckily it was just a $6 coin, but still, it was a big no-no. That was over a decade ago. I still have the coin and just keep it as a reminder of what not to do. I guess the best thing is to just not touch them until more can be learned.

So, rubbing the coins even with a soft cotton cloth should be avoided? Acetone only then. Well, that saves time. Just dip the coins in acetone and that's it. OK. Time to read the other threads now.

magikbilly

<< <i>I guess the best thing is to just not touch them until more can be learned.

<< <i>

Hi there,
the best thing to do IMHO is almost always nothing at all, unless there are serious problems that require proper conservation.

Best,
Billy

satootoko

<< <i>What should I do to clean gold and silver coins without damaging them and lowering their value?
>>

Read this poem, and then do nothing, nada, zilch, nani-mo shimasen, nicht, nil, etc., etc., etc.

Steve27

I would recommend not even using acetone if the fingerprints are old (it won't do anything). If you do go with acetone, use nothing more abrasive than a cotton swab (Q-tip).

coinkat

Please consider leaving them alone and not cleaning them because the probability is that the value of the coins will be reduced... perhaps significantly.

Askari

Welcome, GermanSpirit!

As for cleaning, what Blackhawk and the others have said! Don't clean unless there is an obvious problem. Try an acetone dip with no rubbing (Q-Tip or anything else) first. Do NOT use fingernail polish remover -- it often has extra chemicals in it; you can get straight acetone from any paint supply or hardware store. DO use it in a well-ventilated area, far away from any possible flame or spark, and store it carefully, like you would (or should) do with gasoline. Do not reuse the acetone dip; replace after each coin. Old fingerprints you're stuck with; recent ones that remain after the above dip may be carefully brushed with a clean Q-Tip. Keep contact and pressure to a minimum.

I would advise you to experiment first with low-value coins.

DeutscherGeist

When I bought silver coins, someone touched before it came to my possession, so dipping them in an acetone bath is just a precaution and to insure the coin has no residue on it. It would then be ready to put inside a airtight capsule.

I am only talking about dipping in this case. Forget the rubbing. You guys made me paranoid enough over that.

Here is a problem. I have a 10 Euro silver coin from Germany that had been in a airtight for years. I recently found the capsule cracked on one side exposing the coin. Well, Tarnish set into that one small area and it looks ugly since the rest of the coin is clean silver. If I dip it in acetone, will that make it better. I certainly won't use a silver polish---no way, NEVER!

My grandmother recently gave me an old 2 Mark silver coin that she had for decades. It was virtually black. I looked closer at it and saw it was from the Third Reich. At the time, I thought I would just leave it the way it is because it was interesting that so much tarnish formed naturally through all those years. With the knowledge you guys have bestowed upon me, I can now look back and say my instincts were correct. I have not cleaned that coin and I am going to leave it as is. Sure I have made the mistake of cleaning coins with silver polish--Stupid me...now I know better (they were not anything expensive, so no big deal, nothing to cry over).

BigAlan

Well, Tarnish set into that one small area and it looks ugly since the rest of the coin is clean silver. If I dip it in acetone, will that make it better.

No. Acetone is a solvent. The tarnish is caused by a chemical reaction with something in the air, usually sulfer or clorine.

DeutscherGeist

So, acetone will not do anything to tarnish on silver coins? But what could I do for that small area of tarnish on the silver 10 Mark piece? What does it do to it current value as it is?

Askari

To remove "tarnish", you need to break out a chemistry set, unfortunately. If it's a valuable coin, you can send it to a conservator, but even that is controversial among collectors. Usually it will come back looking "nicer", but not with "original surfaces," so only really messed-up and somewhat expensive coins should be considered for that route. What the spot does to the coin's value depends on how big it is, where it is on the design, etc.

DeutscherGeist

All this knowledge I am getting is wonderful. Kind of disappointing that I am helpless as far as cleaning coins go. It is best just to leave them alone and store them in airtight capsules.

I had no idea that coin surface was so fragile that one cannot even rub them with a 100% cotton cloth.

Steve27

" But what could I do for that small area of tarnish on the silver 10 Mark piece?"

You need to dip it in a mild acid solution, try e*Z*est Coin Cleaner.