Keep handling of the coin itself to the bare minimum. When collectible coins are handled you run the risk of them being nicked, scratched, or dirty and their value is lessened. If circumstances require you to touch your collectibles, do so touching only the outsides, especially with very valuable or rare coins in good condition.

You should try to avoid cleaning your coins and if it has to be done, the process should be handled by a specialist. In fact, the patina developed on a coin over time may actually be a desirable quality to collectors and a cleaned coin could actually decrease it's potential value.

Moisture can cause problems just like fingerprints and dust can, so even though most holders are sufficient to protect your gold coins 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. Never keep your collectible coins in a damp, dark, cool area such as the cellar; instead, choose somewhere dry and with a steady temperature.