Coin collections and coins themselves have a deep rich history and to preserve that history your coins need to be stored properly. Not to mention the monetary value that a well properly stored coin collection will provide to your heirs. Coins are made of metal, and with the exception of gold, most will react negatively with a variety of different environmental factors. Some of the most common metals used in coins are copper and silver. These metals are also some of the most chemically reactive metals known to man. If you know what the enemy is, you can create a defense plan to protect your collection.
The Cause of Damage to Coins
Humidity is a coin's biggest enemy. Coins are made of metal and some of the most common metals that coins are made out of react chemically when they come in contact with water. Water vapor is all around us in varying degrees and it can seep into just about anything.
Heat and Cold
Heat, by itself, does not necessarily damage all types of coins. But heat does reduce the time it takes for a coin to get damaged by other environmental factors such as humidity, acids and air pollution. At the other extreme, cold can also damage the delicate surface of uncirculated coins when humidity condenses into liquid water that will deposit itself onto the surface of your coins.
Acids come from a variety of sources. The most common source is found in coin collecting supplies that are made out of common paper and cardboard that used acids in the manufacturing process. Over time these acids will leach out of the paper or cardboard and cause toning and tarnish especially on copper and silver coins. Acids can also be emitted from adhesives used in packaging, wood furniture and every day household materials such as cleaning solutions and vapors emitted from cooking.
Chlorine causes a chemical reaction that will negatively impact the appearance of your coins. This can range from minor unsightly toning to corrosion that causes pits in the surface of the coin. One of the main sources of this are flips made from plastic that contains PVC (polyvinyl chloride). Additionally, vapors from a hot tub or pool can seep into the area where you store your coin collection.
Not only is air pollution harmful to our health, it is also detrimental to the health of our coin collections. This is mainly a problem in dense urban areas where air pollution from vehicles can accumulate as smog and penetrate the surrounding buildings. Over the years steps have been taken to reduce the amount of harmful gases that vehicles emit, but they can still exist in sufficient quantity to damage a coin.
The most preventable type of damage to coins is caused by improper handling. Touching a coin directly with your fingers can leave deposits of acids and oils that will damage the surface. Also, dropping a coin onto a hard surface can cause irreparable damage that will reduce the coins value. Safe coin handling techniques should always be observed.
Best Storage Solutions for Coins
Choose the Right Holder, Album or Folder
Storing your collection in a cigar box, jar or just tossed into a dresser drawer will cause major damage to your coins. The first step in storing your collection is to ensure that it is properly housed in a coin holder, coin album or coin folder.
Location, Location, Location
As the old real estate adage goes "location, location, location" is everything. Where you store your collection is just as important as how you store your collection. Your basic rule of thumb should be, "if the environment is comfortable enough for a person, it will probably be satisfactory for your coins". Extremes such as a basement (cold and humid) or attic (hot and harsh) must be avoided in order to keep your coin collection in the finest condition possible. A location in a den or bedroom away from the kitchen is the best location.
Safe Deposit Box
One of the safest places to store your coin collection is in a safe deposit box at a bank. Unfortunately, this is probably the most expensive solution too. Bank vaults are constructed to keep criminals and fire out. To deal with the fire issue, the vaults are made with a material that will emit water vapor that will keep the temperature down in the vault. Naturally, some water escapes over time. Therefore, this would provide a very humid environment for your collection. The water vapor can be absorbed by placing a silica gel pack inside your safe deposit box. Remember to change it a couple a times a year to keep it fresh and absorbing as much water vapor as possible.
A less expensive option is to purchase a safe for your home or office to store your coin collection. Once you purchase your safe, there is no reoccurring annual fee like a safe deposit box has. Unfortunately, home and office safes are made out of the same material that bank vaults are constructed of. You must also use a silica gel pack to absorb the humidity and prevent your coins from getting damaged.
Metal Cabinet or Bookshelf
Wooden book shelves and cabinets can emit harmful chemicals into the environment around your coin collection from the coatings, adhesives and the wood itself as it ages. Although not as secure as a safe, a locking metal cabinet will provide a safe environment for your collection since it does not have the problems associated with wood.
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