Instructions
Look for the Topps logo (the word "Topps") on your baseball card. The Topps logo appears on both the front and the back of the card. If your card is not a Topps card, it cannot be a Tiffany card.
Find the date the card was created. This is written in the small print on the back of the card. Tiffany cards were only made between 1984 and 1991, so if your card is from a different year, it is not a Tiffany card.
Examine the surface of your card. If it is glossier than other cards from the same era, it is probably a Tiffany card. If you are not sure if your card is a Tiffany card, take it to a card dealer and ask him what kind of card you have.