Cubic zirconium

Le zirconium cubicoften called cubic zirconia or CZis a synthetic stone that perfectly imitates diamond. It is mainly used in luxury jewelleryCubic zirconium is prized for its brilliance, durability and affordability. Unlike natural diamonds, cubic zirconium is created in a laboratory, which makes it possible to control its quality and physical characteristics.

Origin and manufacture of cubic zirconium

Cubic zirconium is manufactured by a chemical synthesis process. It consists of zirconium dioxide (ZrO2) stabilised with yttrium or calcium to create a cubic crystal structure. This process was first developed in the 1970s and, since then, the technology has been perfected to produce high-quality stones.

The process begins by mixing zirconium dioxide powders and stabilising additives, which are then heated to extremely high temperatures (around 2,750°C). This intense heat melts the materials, which are then slowly cooled to form crystals. These crystals are then cut and polished to create precious stones ready to be set in jewellery.

Characteristics of cubic zirconium

Le cubic zirconium has a number of notable features:

• High refractive index It has a refractive index of 2.15 to 2.18, close to that of diamond, which gives it its brilliant sparkle.
• Hardness With a hardness of 8 to 8.5 on the Mohs scale, it is fairly resistant to scratches, although not as hard as diamond, which has a hardness of 10.
• Clarity and colour Cubic zirconium is generally colourless and free of inclusions, making it visually perfect. However, it can be coloured by adding various metal oxides during the manufacturing process.
• Weight Cubic zirconium is about 75% heavier than a diamond of the same size, which can be an indicator for gemologists.

Why choose cubic zirconium?

Cubic zirconium is a popular alternative to diamond for several reasons:

• Cost : It is much less expensive than diamonds, which makes it accessible to a much larger number of people.
• Ethics Because it is synthetic, it is not associated with the problems of mining and conflict often associated with natural diamonds.
• Aesthetics Its brilliance and clarity make it a very attractive gemstone.

Frequently asked questions about cubic zirconium

Is cubic zirconium as bright as a diamond?

Yes, cubic zirconium is very bright and has a brilliance comparable to that of a diamond. It has a high refractive index, which enables it to reflect light in a similar way to diamond.

Is cubic zirconium easy to scratch?

With a hardness of 8 to 8.5 on the Mohs scale, cubic zirconium is fairly resistant to scratches. However, it is not as hard as diamond (hardness 10) and can be scratched by harder materials.

Does cubic zirconium change colour over time?

No, high-quality cubic zirconium does not change colour over time. However, prolonged exposure to aggressive chemicals can affect its appearance.

How do I care for cubic zirconium jewellery?

To care for cubic zirconia jewellery, we recommend that you clean it regularly with lukewarm water and mild soap. Avoid harsh chemicals and store them separately to avoid scratching.

Is cubic zirconium only used in jewellery?

No, as well as being used in jewellery, cubic zirconium is also used in a variety of industrial applications, thanks to its physical and chemical properties.