Comparison
Moissanite, lab-grown and natural: the honest table
Three colourless stones, three different legal categories and three different price structures. Buyers who blur them get returns and, in some markets, enforcement letters.
| Property | Moissanite | Lab-Grown Diamond | Natural Diamond |
|---|---|---|---|
| Composition | Silicon carbide (SiC) | Carbon, crystal lattice | Carbon, crystal lattice |
| Mohs hardness | 9.25 | 10 | 10 |
| Refractive index | 2.65–2.69 | 2.42 | 2.42 |
| Dispersion (fire) | 0.104 — visibly higher | 0.044 | 0.044 |
| Typical colour | D–J visual equivalent | D–F | D–Z, graded |
| Grading | GRA card; our visual QC | IGI, GIA | GIA, IGI, HRD |
| Disclosure required | Must be sold as moissanite | Must be disclosed as lab-grown | No disclosure beyond natural |
| Wholesale cost index | Low | Mid–high | Highest |
| Resale market | Minimal | Limited but growing | Established |
What the difference looks like in practice
Moissanite
More fire than diamond, especially under point lighting. In daylight the two are hard to separate at a glance; under a jewelry counter lamp the moissanite reads warmer and more colourful. For volume programmes and fashion lines it is the cost-effective choice.
Lab-grown diamond
Optically identical to a natural diamond because it is one. The practical difference is provenance and resale: a lab-grown stone trades at a steep discount to natural on the secondary market, and that gap has widened rather than narrowed.
Natural diamond
The reference stone for fine jewelry and for buyers who need resale value or a recognised grading report. Cost is set by the 4C market, and grading is almost always third-party.
Disclosure: the part buyers get wrong
In the United States, FTC guidance requires that lab-grown diamonds be disclosed as laboratory-created or laboratory-grown wherever they are described. Moissanite must be sold as moissanite — describing it as “diamond simulant” is acceptable only when it is clear it is not a diamond. Neither rule is optional, and marketplaces increasingly enforce both.
What we print on the invoice
The stone type, the metal, the plating and the SKU. If a listing ever reaches your storefront without those four fields, the invoice is the record that protects you.
What the GRA card is, and is not
It is a grading card issued with moissanite, recording weight, shape and measurements. It is not a diamond laboratory report, and it should not be presented as one.
Loose moissanite · Lab-grown diamond loose stones · Materials guide
Stone comparison questions
Does moissanite pass a diamond tester?
Most thermal testers read moissanite as diamond, which is exactly why disclosure matters. Multi-testers that measure refractive index or electrical conductivity identify it correctly.
Is lab-grown diamond the same as cubic zirconia?
No. CZ is a different material with a much lower hardness and a different refractive index. Lab-grown diamond is carbon, identical to natural diamond in composition.
Which stone should a first-time wholesaler stock?
Moissanite in silver for the first order — it keeps the landed cost low, the disclosure rules are straightforward, and the reorder rate is high.