There are several ways someone can tell real crystal from glass, including determining the weight. Crystal weighs more than glass, so if the object is heavier, it is likely crystal.
Crystal also produces a musical tone, where glass does not. Users can test this in one of two ways.
- Use a wet finger
- Use a spoon
Wet a finger and run it around the rim of a crystal glass. If the glass is crystal, it will produce a tone.
Lightly tap the glass with a spoon. If the spoon produces a musical ring, it is most likely crystal.