Cleaning Silver Coins
If silver coins get exposed to air they will get after some time a brown or even black oxidized layer. This is caused by the small amount of sulfur that air contains. By knowing this chemical reaction, we could all imagine that the only way to stop this process is preventing that the coin is surrounded by air. There are ways to seal it in or cover it with an acid-free jelly but most collectors prefer to clean the coins. Because most coins are exposed to air cleaning will be necessary after some time. The cleaning of silver coins can be done by different methods and on this page, we like to present to you this specific information and how this can be done safely. Keep in mind that for some coins, like ancient roman coins it might be wise not to clean them totally as they look more authentic with a light (ancient-looking) color change caused by this natural silver oxidation effect.
Method 1: Lemon Acid
Put the coin in a lemon acid bath for some hours to maximum one day depending on the thickness of the oxidation layer to be removed from the coin. After this bath clean the coin carefully with a soft brush, rinse it with water and dry it with soft paper. The effect of this method can be improved by putting some small iron nails in the lemon acid bath. This will improve the chemical reduction of the lemon acid bath and faster cleaning of the silver coin will occur. If you use some small iron nails do not leave the silver coin longer in the lemon acid bath then 30 minutes maximum and use the procedure as described earlier.
Method 2: Acid Fluid
If the silver coin you want to clean has only some small oxidation spots then you can clean them best with an acid fluid-like warm vinegar or sour milk on soft tissue or a raw potato cut in half and rub the coin with it. After cleaning it rinse it well with water and dry the coin with a soft paper tissue.
Method 3: Using Silver Cleaners
There are various ready-made silver cleaning products for sale and they can be used for cleaning heavy oxidized silver coins. They clean silver coins in several seconds and here lays also the problem when using one of these products. Because the cleaning process goes so fast you can’t stop at a specific level where the coin has still that little oxidized effect, as we want with ancient roman coins. For this reason, we advise method 1 or 2 for cleaning your silver coins unless you know what you are doing when using method 3.
At last, we like to give you a piece of good advice and this is good to know before cleaning. If you are intending to sell your silver coins, do not clean them as potential buyers will give you more for it when it’s brown or black by this natural process! In other words, a brown or black silver coin is more worth than a coin that has been cleaned the wrong way or just to much cleaned !!