If you have recently bought an old coin or several old coins, or if you have recently come into an inheritance of such, you will have to know how to clean these old coins in a manner such that the value of these coins is not diminished. A valuable and rare coin might lose its value if it is rubbed with a substance that is abrasive. Old coins are said to have some form of coating called ‘toning' on them, which is reflected as a kind of varnish or patina on them, so that to retain their value it is important to preserve the ‘toning.' For instance, old silver coins are known to develop a rainbow-colored patina on their surface that is due to the accumulation of certain substances found in the atmosphere.
It is also important to take note of the fact that when you handle old coins with your bare hands your fingers tend to exude some form of oil that might ruin this patina. Therefore when handling old coins, you should wear latex gloves. When handling these, you must also handle the edges only. Coins are also best kept in a dark environment where the humidity is controlled, in order to preserve their state. They thus could be kept in a safety deposit box, or in special coin collection cabinets.
- The best way to clean old coins is simply to wash them with mild dishwashing liquid. You should wash your hands first, and then prepare a towel on which the coins can be set to dry. The best place to wash old coins is a plastic container, such as a large plastic bowl or tub. Using containers such as metal, china or glass might be quite hazardous especially when the coins scratch against these surfaces. A second similar container must be prepared containing the last rinse. The water in this rinse should be warm if possible. Experts say that distilled water is the best for cleaning and rinsing.
- Start cleaning the coins one by one. Rub gently on the sides of the coin to remove dirt and dust, and work your fingers in an outward motion. Avoid rubbing many coins together as they will come into contact with one another, causing scratches on the surfaces.
- Rinse the coin first under running water. Using your fingers, only the edges of the coin should be touched from hereon. Lastly immerse the coin in the warm last rinse, and then lay it down and the towel and simply pat it dry using either a dry soft towel or a soft paper towel. Do not rub the coin. Do the same steps above for all the coins, still remembering to wash them one by one.
As a final reminder, it is important again that nothing else except water and mild soap is used on the coin. Metal polish, oils or other chemical substances must never be used on them. Doing so will tarnish the coin, and just help in diminishing its value.