While the appearance of diamond simulants is similar to that of natural diamonds, they are not diamonds. Common diamond simulants include glass and cubic zirconia (CZ), both of which are completely unrelated to diamond at the atomic level. Simulants are generally less expensive than the real thing. They allow consumers to enjoy the flash and dazzle of diamond-like jewelry and to inexpensively complement the latest fashion trend. But no matter how convincing the illusion, all diamond simulants have optical and physical characteristics that can be identified by a trained gemologist.