Cubic zirconia

[Lanell]

[Cubic zirconia] (sometimes called simply cz) is the most popular diamond simulant in the world today. It is an [oxide] of the metallic element zirconium, [ZrO]². It has a [hardness] of about 8.5 on the [Mohs] hardness scale, as opposed to diamond, which is 10, [sapphire]/ruby which is 9, [topaz] which is 8, and so on. The refractive index of [CZ] is 2.42. It can be made in nearly any color and can be faceted into many cuts.
CZ occurs naturally but in pieces too small for jewelry purposes. It wasnt until the 1970s however when Soviet scientists learned how to grow this mineral in the laboratory, at which time jewelry designers first took notice of [cubic zirconia]. For the first few years it was on the market it was often sold for as much as per [carat] (!!) and was only available in a few colors.
CZ is more dense than diamond -- it weighs more for its size than diamond does. [Sapphire] and ruby, both of which are the same [gemstone], just different colors, are also more dense than diamond. CZ is about 75% heavier than diamond. As such, a [CZs] size is referred to in [carats] usually in comparison to diamonds. [CZs] are more accurately measured in millimeters, referring to the width of the stone. A 6.5 mm cubic zirconia is equal in size to a one-carat diamond and actually weighs about [1.75] carats.
CZ isnt grown/created like any other imitation gemstone in the world, either. A high radio-frequency skull [crucible] system is used, in which the melting zirconia powder actually creates the sides of its own container during its formation. Cooling this extremely hot molten ore becomes the most crucial step in the entire process. A carefully programmed cooling procedure is required to form the flawless crystals -- metal pipes in a coil-shape with water running through them are used to cool down the material, in the center.