What is Moissanite?
Moissanite is a gemstone made from silicon carbide. Natural moissanite is very rare. The stones used in modern jewellery are created in a lab. Moissanite is not a diamond, although both can be colourless and cut in similar shapes.
- Composition
- Silicon carbide
- Jewellery source
- Lab-created
- Mohs hardness
- About 9.25
- Refractive index
- 2.65 to 2.69
These properties describe the material. Cut, shape and lighting still affect how an individual stone looks.
Moissanite: quick facts
| Composition | Silicon carbide |
|---|---|
| Source used in jewellery | Laboratory-created |
| Mohs hardness | About 9.25 |
| Refractive index | Approximately 2.65 to 2.69 |
| Optical character | High brilliance, strong spectral flashes and double refraction |
French chemist Henri Moissan found natural silicon carbide in material from the Canyon Diablo meteorite in 1893. The mineral was later named moissanite. Natural crystals are rare and usually too small for commercial jewellery. As a result, jewellery-grade moissanite is lab-created.
What does moissanite look like?
Moissanite returns a great deal of white and coloured light. Its dispersion is higher than diamond's. This can make rainbow flashes easier to see in direct sun or spot lighting. It is a feature of the material, not a grading defect.
Moissanite is doubly refractive. In some cuts, facet edges may look slightly doubled through the stone. Cut, shape and viewing angle affect how easy this is to see.
Colour and clarity
Moissanite is sold in colourless and near-colourless ranges. Some stones can show a faint warm, grey or green cast in certain lighting. Clarity grades describe visible inclusions, but they do not measure cut quality or overall appearance. Review the stone in daylight, indoor light and close-up video when possible.
Durability and everyday care
At about 9.25 on the Mohs scale, moissanite resists scratching better than many jewellery stones. Hardness measures scratch resistance, not resistance to impact. A stone can still chip if struck. Its setting can also bend or loosen with wear.
- Remove jewellery before exercise, heavy lifting, housework or swimming.
- Avoid chlorine, bleach, abrasive cleaners and toothpaste.
- For routine cleaning, use lukewarm water, mild soap and a very soft brush. Rinse carefully and dry with a lint-free cloth.
- Store pieces separately so metal and stones do not rub against one another.
- Have prongs and settings checked if a stone moves, catches on fabric or receives a hard knock.
Moissanite, diamond and cubic zirconia
These are different materials. A comparison is useful for understanding their properties, but it does not determine which one a person should prefer.
| Property | Moissanite | Diamond | Cubic zirconia |
|---|---|---|---|
| Composition | Silicon carbide | Carbon | Zirconium dioxide |
| Common jewellery source | Lab-created | Mined or lab-grown | Lab-created |
| Mohs hardness | About 9.25 | 10 | About 8 to 8.5 |
| Light pattern | Strong brilliance and coloured fire | Balanced brightness, fire and contrast, depending on cut | Bright appearance with lower refractive index |
| Optical structure | Doubly refractive | Singly refractive | Singly refractive |
A lab-grown diamond is a diamond. Moissanite and cubic zirconia are diamond simulants because they can resemble a diamond but have different chemical and optical properties.
What a certificate or report tells you
A lab report may record the stone's material, shape, size, colour range, clarity range and identifying features. Fields and grading methods vary by lab. A report is not an independent valuation. It also does not guarantee resale value or assess the finished setting unless this is stated.
For Myraé jewellery, HIDL and/or GRA documentation is available on request where applicable. Confirm which report will accompany the specific piece before ordering.
Technical references: Gemological Institute of America and FTC Jewelry Guides.