Diamond Nexus Diamond Simulant vs. CZ

Our Diamond Simulants are different from a CZ (cubic zirconia) in four key ways: weight, hardness, coating, and chemical composition. The result, a superior Diamond Nexus Diamond Simulant with qualities extremely close to that of a mined diamond.


Our Diamond Simulant weighs 15% - 20% more than a CZ of the same size, and a CZ will weight relatively 1.7 times more than that of a diamond of the same size.


Our Diamond Simulant is very hard. The chemical composition of CZ makes it a softer, more porous stone. For example: over time, as you wear a CZ, it will absorb the oils in your skin, the soap you use to wash your hands, etc... Eventually, the CZ will appear yellowish and lose its fire and ability to disperse light. Due to the softness of the stone, its facets will also wear down with use. The hardest a CZ stone will ever be is an 8.5 on the Mohs’ hardness scale. A Diamond Simulant is closer to the properties of a mined diamond. As such, it will not chip, fade, or lose its brilliance over time. The average hardness of a Diamond Simulant is a 9.1-9.2 on the Mohs’ hardness scale, much closer to that of our lab diamonds (and mined) that are a perfect 10.


A lot of companies sell a common CZ and put a coating on their product as a way to differentiate it. Sometimes the language used is "diamond infused", "diamond hybrid" or "sealed in a diamond". The coating they are referring to is called "DLC", which means "diamond-like coating". This coating process has been around for years, and the "diamond" coating being referred to is "amorphous carbon" which is really pencil lead. When a stone is coated with amorphous carbon, the coating must be exceedingly thin as to be essentially non-existent. Otherwise, the stone would be discolored.

At Diamond Nexus, we also have a coating on our Diamond Simualnts. Our coating material is Corundum and other proprietary materials which is substantial, visible under microscopy, and has important measurable physical characteristics. The coating seals the surface of the Diamond Simulant, greatly lowering porosity, and making the stone impervious to outside contaminants. It also increases the hardness and the ability of the Simulant to resist scratches. Below you can see an example of our coating - which depicts its thickness at 131.2nm, over 10,000 times thicker than our competitors.


Diamond Nexus electron microscopy

Electron microscopy image of Diamond Nexus coating


Chemical Composition

CZ (or cubic zirconia) is made of zirconium oxide and sometimes a yttrium stabilizer. Diamond Simulants are comprised of (in order of atomic weight):

Carbon (C)
Sulfur (S)
Iron (Fe)
Calcium (Ca)
Cobalt (Co)
Nickel (Ni)
Yttrium (Y)
Zirconium (Zr)
Gadolinium (Gd)
Hafnium (Hf)

Diamond Nexus vs. Moissanite

Below you will see two charts from an independent lab report which shows a spectrographic analysis for CZ and for our Diamond Simulants. A spectrographic analysis is an analysis which uses a spectroscope (an optical device for producing and observing a spectrum of light or radiation from any source) to determine the chemical elements in a source by measurement of the wavelength and spectral line intensity produced by any one of several methods of excitation such as arc, flame, infrared and X-ray. As you can see from the data, our Diamond Simulants are not Cubic Zirconia. We have gone to great lengths to create a Diamond Simulant that is nearly the same physically and optically to a mined diamond. The difference is in the chemistry-and that exact formula is proprietary.


Spectographic Analysis


How is our Diamond Simulant different from Moissanite?

Our Diamond Simulant is different from Moissanite in much the same way that a diamond is different from Moissanite. While Moissanite is beautiful in its own right, it does not function chemically or optically like a diamond or a Diamond Simulant. Chemically, it is silcon carbide. Unlike a diamond or our Diamond Simulant, moissanite is strongly birefringent or doubly refractive. This is a desirable quality in some optical applications, but is not desirable in gemstones. For this reason, Moissanite jewels are cut along the optic axis of the crystal to minimize birefringent effects. Moissanite's higher index of refraction (brilliance) and much greater dispersion (fire) than either a diamond or Diamond Simulant make it easy with the naked eye to distinguish a Moissanite from our stone and from a diamond. Finally, where the best quality diamonds and Diamond Simulants have a D color (meaning virtually colorless), a moissanite stone has a slight green tint to it that becomes more noticeable with increasing carat sizes.

Property Mined Diamond Diamond Nexus Moissanite
Brilliance 7.40 7.40 8.90
Dispersion 0.44 0.46 1.01
Refraction 2.40 2.20 2.68
Refraction Type Isometric Isometric Hexagonal
Crystal System Single Single Double
Birefringence No No Yes
Luster Adamantine Adamantine Viteous
Fracture Conchoidal Conchoidal Conchoidal
Color Streak Colorless Colorless Grey/Green


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