If possible, steer clear of handling your coins. In the world of collectible coins, value is directly correlated to condition and quality, which is lessened when scratches, smudges, fingerprints or scratches are present. If circumstances require you to touch your collectibles, do so touching only the outsides, especially with very valuable or rare coins in good condition.

It is not recommended that you clean your coins, but if you do, you should be sure to entrust the process to a specialist. A coin's patina, gradually developed over a period of time, might increase the coin's desirability, whereas cleaning the coin could make it less valuable.

Moisture can cause problems just like fingerprints and dust can, so even though most holders are sufficient to protect your twenty cent pieces make sure your most valuable pieces are really protected. There are other protectors in the market that can do a better job and guard against moisture than the typical stapled or taped packets, which don’t provide the maximum protection. Avoid any storage space that is damp and cool when selecting a storage area for your collectible coins.