While it's often necessary for an expert to examine the item, crystal can be distinguished by its ability to cast rainbow colors when held up to the light. Real crystal also contains lead, so it is heavier than glass and reverberates a distinct ringing sound when struck.
Crystal can be recognized by its shining silver hue, compared to the clean transparency of glass. Crystal also tends to have rounder and smoother cuts than glass. Glassware rarely contains lead, whereas crystal contains at least 24 percent. Typical glassware is made from around 50 percent sand, which explains why crystal is more durable than glass.