Avoid touching your coins as much as possible. A coins' quality and value decline when scratched, dusty, damaged by moisture or when fingerprints are present. Direct contact with your collection should be avoided, especially with coins in mint condition, but if you have to touch please do so by only holding the outer edge.

Cleaning coins is not recommended and should be done only by an expert, and only when absolutely necessary. Removing the patina that develops on an old coin could also decrease its value, as collectors might prefer coins with this evidence of age.

Fingerprints and dust aren't the only culprits in compromising your coin collection; moisture can damage proof dets over the long run, so make sure the holder you choose protects against it. Stapled or taped packets don’t give maximum protection, but there are other protectors in the market that can also guard effectively against moisture. Never keep your collectible coins in a damp, dark, cool area such as the cellar; instead, choose somewhere dry and with a steady temperature.