How to Handle & Clean Your Coins
Get Tips from the Experts on Cleaning & Handling Coins
By Alan Herbert
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Handling Your Coins
At first you may be skeptical of the information in this section, but itís important advice that will stay with you as long as you collect.
We all are used to touching and holding coins. You pull out a handful and spend them, or pay for something and put the rest back in your pocket or purse. How did you hold the coins you used?
Most likely you made one of the most common of mistakes in handling coins for a collection. You held the coin between your thumb and finger, pressed on the front and back of the coin, what collectors call the obverse and reverse of the coin.
If you touch a coin like that, it is generally not a problem, since most circulated coins show obvious wear when you look at them. However, for an uncirculated or proof coin, you just damaged the coin. The natural oils in your skin will etch a fingerprint or a thumbprint into the surface of the coin in a matter of minutes. Once the fingerprint is on the coin itís impossible to remove without further damaging the coin.
Always hold a coin by the edge, never the faces.
Itís a good habit to get into, even with common, circulated coins. To prevent damage to a coin you are examining, hold the coin by its edges with your thumb and forefinger. Handling coins this way is good practice for when you hold rare of valuable coins.
If you are working with upper-grade, uncirculated or proof coins, a pair of lintless cotton gloves is strongly recommended. Latex or plastic gloves are not recommended because they often have powder or lubricants on them that may damage the coin. Also, consider placing a thick, soft cloth under the coin as you are holding it, just in case you slip or drop the coin. This will prevent damage to the coin that might come from it impacting a hard surface.
Family or friends may want to touch the coins in your collection. You can either warn them not to touch the coins, or show them how to properly handle them.
Another possibility would be to put the coins in holders that protect the surface of the coin. This allows for easier handling, and can provide protection from damage that might be caused by an accidental drop.
Many an old-time coin collector (or coin dealer) will use the ďringĒ test to determine if a coin is silver. Not only is this a negative test, it will also cause damage to the coin, since the test involves dropping the coin on a hard surface. This is a negative test, because the slightest fissure or internal crack in the coin will make it sound like a lead washer. Weighing the coin will tell you as much, or more, about the coin, and weighing is a non-destructive test. To prevent damage to your coins, donít let someone else ďringĒ your coins, ever.
Donít scratch, cut, clean, rub or polish a coin for any reason.
Itís nearly impossible to cut through copper plating, the metal curls around the blade, giving you the false impression that the coin is solid copper. Stop anyone else from ďtestingĒ your coin in this fashion. The damage done will often cut the collector value of the coin in half, or worse. Weighing the coin will tell you a lot more, and as previously noted, itís a non-destructive test.
The whole idea behind proper coin handling techniques is to prevent damage to the coinís surface, mint-produced or otherwise. The more wear or damage there is to the coinís surface, the less will be the coin's worth. The whole basis of collecting coins revolves around protecting and preserving that mint surface. Iíll expand on this theme in the next chapter.
How to Care for & Clean Your Coins
This is a good place to repeat, ďDonít clean your coins.Ē
If you donít learn anything else from this section, this rule should be it.
There are two types of cleaning for coins, often confused with each other.
Destructive cleaning uses abrasives or acids to clean (and alter) the coin surfaces. Non-destructive cleaning uses solvents that are harmless to the coinís metal, whether that coin be silver, gold, or modern clad composition.
Destructive coin cleaning will reduce the collector value as much as 50 percent or even more. An expert can, in some cases, improve the value of an old coin by cleaning, but for the average collector the risk of damage is too great, as almost anything you do is going to cut the value. Unless you are an experienced specialist, the answer to ďhow do I clean my coins?Ē is, quite simply, ďdonít clean them.Ē The typical response from people who donít take advice kindly is ďIíll do as I please with my coins and you can go jump in the lake!Ē Have a nice swim.
Some collectors insist on cleaning their coins. One such collector had thousands of silver dollars. Every coin had been scrubbed with a harsh abrasive, every coin he bought got the same treatment, despite warnings from friends and dealers he did business with. The result, after he was done cleaning the silver coins, the only value left was the silver content, less than an ounce in each coin.
Another collector put his coins through a rock tumbler, hardly one of the proper coin cleaning materials. It ruined the collectionís value.
The metal cleaners you see offered for sale on TV and elsewhere all are acid-based cleaners. They remove some of the surface metal in the process of cleaning a coin. Avoid such coin cleaning products at all costs. Even a modern clad coin cleaned with one of these products will lose value. Ancient coins, or gold and silver coins will lose collectorís value, and precious metal content through use of such cleaners.
A weak soap (not detergent) solution in distilled water will remove dirt and grease from an encrusted coin without damaging it, even if the coin is one of those grimy specimens found at the beach.
City tap water has chlorine in it, which will discolor the coin. Use distilled water, and rinse with distilled water. Acetone is another commonly used solvent, but there is a fire hazard that you should be aware of when using it as a coin cleaning material. Fingernail polish remover contains acetone, but it has other chemicals that may cause damage to upper grade coins.
Also this warning: There is no safe method available to clean your upper grade uncirculated or proof coins or copper alloy coins. Always seek professional help and advice concerning these valuable coins.
After using solvents, itís important to rinse the coins with distilled water, and then either allow them to air dry, or pat them dry. Never rub, even with the softest cloth.
Heavily encrusted coins can be soaked for several months in olive oil. The oil wonít damage the coin further, but it will eventually dissolve the crust. Generally speaking though, trying to restore badly corroded coins is a waste of time. Even if you successfully remove the corrosion, there is usually permanent damage underneath, leaving you with a near worthless coin. The same applies to the patina on ancient coins, which in some cases can actually contribute to a coinís value.
Donít buy coins that have been cleaned. The bargain prices indicate the coins will not appreciate as quickly as coins left uncleaned.
Anywhere else, the discoloration on silver coins is called tarnish, but coin collectors blithely refer to it as ďtoning.Ē It can range from black to many of the rainbow colors, and some collectors will pay a premium for nice looking toning. This comes close to being a fad. It is also subject to abuse from artificial toning.
An ultrasound cleaner will work, but with care. Only one coin at a time should be cleaned and the solution in the bowl should be changed frequently.
Another threat to your coins is PVC (polyvinyl chloride). It is a softener used in plastics, such as the 2-x-2 coin flips. When it deteriorates, from age or excessive heat, it creates a green slime that will eat into the surface of the coin, doing irreversible and permanent damage to the coin. There are Mylar flips available which do not have this problem, if you have questions, check with your dealer, they can give you important advice on the products they sell, and on how to prevent damage to your collection in general.
Donít buy a cleaned coin unless it is absolutely the last resort.
Cleaned coins will show little or no appreciation, lagging far behind an uncleaned version of the same coin.