Both are colourless, both are inexpensive compared with diamond, and both are sold as diamond alternatives. They behave very differently after a year of wear.
Hardness
Moissanite is 9.25 on the Mohs scale; cubic zirconia is 8–8.5. That sounds close, but hardness is logarithmic in abrasion resistance: CZ scratches from everyday grit and loses its polish, while moissanite keeps a crisp facet edge for decades.
Stability
CZ is stable but soft enough that facet junctions round off with wear, which is what people describe as “going cloudy”. Moissanite does not cloud — surface film from soap and skin oil does, and it cleans off.
Optics
Moissanite has a refractive index of 2.65–2.69 and dispersion of 0.104, so it throws strong coloured fire. CZ is 2.15 and 0.060 — brighter than glass, flatter than moissanite. In daylight, the difference is obvious to anyone who has seen both.
Weight and feel
Moissanite is lighter than diamond and CZ is heavier. In the hand, a CZ feels dense and slightly “glassy”; moissanite feels like a diamond of a larger size.
Price
CZ is cheaper by an order of magnitude. A CZ ring is a reasonable purchase for a costume piece, a travel ring or a design test; it is a poor choice for a ring worn daily for years.
When CZ is the right choice
- Testing a design before committing to a precious version.
- A statement piece worn occasionally.
- A budget where the alternative is not buying anything.
When moissanite is the right choice
Any ring worn daily, especially an engagement ring. The cost difference over five years is small compared with replacing a clouded CZ three times.
We sell both, and we will tell you which suits the piece. Moissanite jewelry → · Zirconia →
The people who cut the stones and set the rings. We publish what we can verify on our own bench, and link to the certificate or the guide when a number needs a source.
