Guide
Moissanite vs. Diamond: The Complete Comparison
Understanding brilliance, durability, and value — so you can choose with confidence.
What is moissanite?
Moissanite is a gemstone made of silicon carbide, first discovered in a meteor crater in 1893 by French scientist Henri Moissan. Because natural moissanite is exceptionally rare, the stones used in modern jewelry are lab-grown to jewelry-grade purity — engineered for maximum fire, brilliance, and durability.
Every stone in a Moissan piece is GRA Certified and passes standard diamond testers, with D color, VVS1 clarity, and an excellent cut.
At a glance
| Property | Moissanite | Diamond |
|---|---|---|
| Hardness (Mohs) | 9.25 – 9.5 | 10 |
| Refractive index | 2.65 – 2.69 | 2.42 |
| Fire (dispersion) | 0.104 | 0.044 |
| Color grade | D (colorless) | Varies |
| Clarity | VVS1 | Varies |
| Passes diamond tester | Yes | Yes |
| Origin | Lab-grown | Mined or lab-grown |
| Relative cost | ~10% of diamond | Full market price |
Brilliance and fire
Brilliance is how a stone returns white light; fire is the rainbow flash you see when it moves. Moissanite has a higher refractive index (2.65–2.69) than diamond (2.42), and more than two and a half times the dispersion — the property responsible for fire. In practical terms: a well-cut moissanite throws noticeably more colored flash than a diamond of the same size, while matching it for white-light sparkle.
Durability for everyday wear
On the Mohs hardness scale, diamond sits at 10 and moissanite at 9.25–9.5. Only diamond is harder. Both stones resist scratching, chipping, and clouding, making them equally appropriate for engagement rings, tennis chains, and pieces you plan to wear daily for decades.
Certification and testing
Every Moissan stone ships with a GRA certificate documenting its color, clarity, cut, and carat, and each passes a standard thermal diamond tester because moissanite conducts heat similarly to diamond. You get verifiable quality — and a stone that reads the way you'd expect it to at any jeweler.
Cost and value
The most immediate difference is price. A carat-for-carat comparison typically puts moissanite at roughly one-tenth the price of a mined diamond of similar visual quality. That means a larger stone, a more substantial setting, or a full matching set — for the same budget.
Which should you choose?
If you want maximum fire, ethical lab-grown origin, and exceptional value without compromising on the look of fine jewelry, moissanite is the modern choice. If provenance from a natural mined diamond is essential to you, a traditional diamond may be worth the premium. For most everyday luxury — engagement rings, tennis bracelets, studs, pendants — moissanite delivers the look and feel of fine jewelry at a fraction of the cost.