Here are some quick tips on how to distinguish classic crystal from plain glass:
- Hold up a glass to the light. If the glass acts as a prism and you see a rainbow you are holding crystal. If not, it is just plain glass.
- When struck, crystal produces a musical ring. Glass does not.
- If you wet your finger and run it around the rim of a crystal glass it will also produce a musical tone.
- Crystal can be worked thinner than glass, so if the rim of a piece is exceptionally thin it's probably crystal.
- If you compare two glasses of the same size, the crystal glass will be heavier.
- Glass typically has sharp cuts, while crystal will have clean, rounded cuts.