Diamond Knowledge

Moissanite vs Diamond

Moissanite is a beautiful stone in its own right — but it is not a diamond. Knowing the difference, and saying so plainly, is what honest selling looks like.

← Part of the Brilliani Labs Diamond Guide

Is moissanite a diamond?

No. Moissanite is a different material (silicon carbide), almost always lab-created. It is a diamond simulant — a stone that looks like a diamond but is not one. By contrast, a lab-grown diamond genuinely is a diamond. If you want the distinction in full, see simulants in the Diamond Guide.

How does moissanite look different from a diamond?

Moissanite disperses light more strongly, so it shows more fire — more rainbow flashes. Some love that extra colour; to a trained eye it can read as a slightly different, more "disco" sparkle than a diamond's balance of white and coloured light.

Can you tell moissanite from a diamond?

Often, with experience. Under magnification moissanite shows a doubling of the back facets (it is doubly refractive, unlike diamond). A definitive answer comes from a proper tester or a laboratory.

Is moissanite as hard as a diamond?

Moissanite is very hard and well suited to daily wear, but diamond is the hardest natural material. On the Mohs scale diamond is 10 and moissanite a little below it, so a diamond still resists scratching best.

Does moissanite test as a diamond?

Simple thermal testers can struggle, because moissanite conducts heat similarly; modern dual testers separate the two. Its double refraction is another giveaway under magnification.

Is moissanite cheaper than a diamond?

Yes, considerably, for a similar size and look.

Moissanite or a lab-grown diamond — which should I choose?

If you want a diamond, a lab-grown diamond gives you exactly that at a lower price than a natural one. If you are happy with a different material and a livelier fire, moissanite costs less again. Neither is wrong — the honest question is whether you want a diamond.

Is moissanite "fake"?

No. It is a real gemstone, just not a diamond. The fair way to describe it is as a diamond simulant or alternative, always disclosed — never sold as a diamond.