Zirconium oxide, commonly known as zirconia, is an inorganic zirconium compound with the formula ZrO2. Thanks to its high refractive index, it is one of the best substitutes for diamond, imitating its brilliance to perfection. However, while its density is higher than that of diamond, its hardness is slightly lower.
Properties of zirconium oxide
- Type: Synthetic stone
- Color: Colorless and all colors
- Hardness: 8.5 on the Mohs scale
- Family: Zirconium dioxide
Invention
Zirconium oxide was invented in 1973. It was created in a laboratory at the Moscow Institute of Physical Sciences by researchers keen to offer a perfect imitation of diamond. Their idea was to mix zirconium oxide with calcium oxide. The result so closely resembled diamond that the jewelry world immediately adopted it.
Characteristics of zirconium oxide
Zirconium oxide’s aesthetic appeal and mechanical properties – a virtually scratch-proof and extremely resistant stone– have made it the material of choice for jewelry-making. In fact, zirconium can be used to create jewelry-like pieces at affordable prices.
How can you tell the difference with diamond?
Only laboratory tests can effectively establish whether a diamond is genuine or zirconium oxide. But there’s a simple test you can use to make a quick distinction. It consists in fogging up the stone to be tested with your breath, holding the stone’s culet upwards. Fog disappears much more quickly from the surface of a diamond than from that of a synthetic stone. Ideally, you should have a real diamond with you, to serve as a reference for the stone to be tested.
What’s the difference between zircon and zirconium oxide?
In jewelry, it’s very common to find the two terminologies ‘zircon’ and ‘zirconium oxide’. But even if the names of the two stones are similar, they are in fact quite different.
Zircon is a natural stone from the silicate family. Zircon has been known and mined since ancient times: it has been found on some of the world’s oldest archaeological sites and is thought to have been one of the first gems used in jewelry.
For centuries, transparent zircon was used as a substitute for diamonds in low-cost jewelry. But, although its lustre and brilliance are close to those of diamonds, it has a lower resistance and offers less brilliance than diamonds. It is a fragile, shock-sensitive stone that must be handled with care.
Zirconium oxide is a synthetic stone produced in laboratories and created entirely by man.
The difference between zirconium oxide and rhinestones (crystal)
Strass is a crystal (glass) with a lead oxide content of up to 50%, far higher than that of ordinary crystal. It is this high percentage of lead oxide that gives it a very high refractive index and good brilliance, enabling it to be used in the manufacture of costume jewelry.
Zirconium oxide is a much more resistant and brilliant stone than rhinestone, which is simply glass.
How do I care for zirconium oxide?
Not only is zirconium oxide just as luminous as diamond, it’s also very easy to clean. All you need to do is dust it from time to time with a soft, dry cloth. If you prefer, you can wash it beforehand with warm water and soap. In fact, like diamonds, zirconia’s brilliance never fades. It’s timeless!
