Diamond simulant refers to any material that has the appearance of diamond but does not posess the characteristics, atomic structure, chemical composition and physical properties of natural diamond.Which of the following Zirconium compounds is used as a diamond simulant?

Zirconium dioxide (ZrO₂),  is a white crystalline oxide of zirconium. Its most naturally occurring form, with a monoclinic crystalline structure, is the rare mineral baddeleyite. The high temperature cubic crystalline form is rarely found in nature as mineral tazheranite (Zr,Ti,Ca)O₂ (a doubtful mineral arkelite). This form, also called cubic zirconia, is synthesized in various colours for use as a gemstone and a diamond simulant.