If you are about to buy an unopened pack be very careful. Since the pack is sealed, there is no guarantee the cards inside are the real thing. Yes, beware! There are unscrupulous operators around who will try to rip you off.

How do know if an unopened pack is genuine? Short of opening the pack there is no sure way of knowing. If you're really crafty, and have the means, you could probably have carbon dating done on the glue. Thinking practically though, all you can really do is take the word of the dealer. Perhaps you can ask him if he has more than one pack. If he does, ask him to show you the other packs. Perhaps comparing the lot would help you to judge the authenticity of the one you are buying.

If an unopened pack has an overall used and handled look about it or if the package feels loose and the wrapper appears to have an unusually high number of creases on it then be very suspicious! Finally, unopened packs should have a small stick of gum inside so feel around for the 30 year old treat.