Cubic zirconia (or CZ) is the cubic crystalline form of zirconium dioxide (ZrO2). The synthesized material is hard, optically flawless and usually colorless, but may be made in a variety of different colors.
Set into jewelry, cubic zirconia is a great substitute for diamond and is available in many colors. Pandora is a big user of cubic zirconia to create their unique and beautiful beads and jewelry.
Because of its low cost, durability, and close visual likeness to diamond, synthetic cubic zirconia has remained the most gemologically and economically important competitor for diamonds since commercial production began in 1976.