If your coins are a few years (or hundreds of years) old, then there is a good chance that they may look a little dull, maybe discoloured, dirty, moldy, show fingerprints and all sorts of thing that you may think spoil it from its former mint-state glory.
Here’s what to do: NOTHING!
Don’t clean or polish your coins
I’ve been at valuations where collections that should have been worth several thousand pounds have been rendered literally worthless just because the owner has decided to get the metal polish out and give them a good rub. No coin collector will want to purchase a coin that has been polished up.
Don’t use the silver wipes, dips, sprays, soft toothbrush and gentle rub advice. If you really need to clean a coin then ask a professional dealer for advice – and even then consider the consequences that you may make matters worse.
You may think discolouration detracts from a coin’s appearance, but I’ve seen professional collectors get excited about the ‘outstanding patina’ of coins. It shows character and authenticity; professional dealers tend to spot fake patina’s quite quickly.
The patina may not only add value to the coin but also protects it from further deterioration and may hide unsightly scratches and pits in the surface.
Prevention is better than cure
If you have a nice coin then you should look after it. Coins are metal and they will degrade with time due to natural chemical reactions; your job is to slow these processes as much as possible. Even exposure to the atmosphere is unsafe. Here’s some advice:
Avoid touching your coins. Your fingers contain chemicals that may react with the coin and attack the metal finish. Besides, a fingerprint on the surface of a coin is always bad for a collector and can be near impossible to remove.
If you must handle coins either wear suitable gloves (like cotton gloves) or just hold the coin by the edge. Don’t breathe or blow on the coin. Be careful where you put the coin as some materials can be harmful, and these may be common items like cardboard or wood.
Keep your coins in approved containers. There are many specially made coin wallets, pouches, screw top encapsulations, etc. They are inexpensive and are specially made from material that does not react with coins. It will also make it easier for you to handle the coins without actually touching them directly.
Don’t use normal plastic or food bags, use only plastics and material approved for coin storage. If the coin already came in encapsulation then it’s probably best to leave it in there.
When you’re not looking at your collection, keep it in a dark, dry, preferably temperature controlled – and secure – place.
It is worth the effort to look after your coins. You’ll appreciate them more and if you decide to sell them in the future then you’ll be glad you did.
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