Moissanite and diamond look alike at a glance, but they are different stones. Here is how they compare in plain numbers, so you can choose what's right for you.
What is moissanite?
Moissanite is silicon carbide. The French chemist Henri Moissan first identified it in 1893, in fragments of a meteorite. Natural moissanite is extremely rare, so the moissanite used in jewellery today is created in a lab. It is not a diamond, and we never sell it as one.
Sparkle: fire and brilliance
Fire is the flashes of rainbow colour you see when a stone moves. It comes from dispersion: how strongly a stone splits white light into colours. Moissanite's dispersion is 0.104 and diamond's is 0.044, so moissanite shows more coloured flashes, especially in sunlight.
Brilliance is the white light a stone sends back to your eye. It relates to refractive index: 2.65–2.69 for moissanite, 2.42 for diamond.
Some people love the extra colour; others prefer the cooler look of diamond. It's a matter of taste.
Hardness: can you wear it every day?
On the Mohs hardness scale moissanite is 9.25 and diamond is 10. Sapphire and ruby are 9. Moissanite is hard enough for everyday wear.
Will moissanite pass a diamond tester?
Basic thermal testers can read moissanite as diamond, because both carry heat well. Testers that also check electrical conductivity can tell them apart. Moissanite is a beautiful stone in its own right, not a fake diamond.
Price
Diamond studs with 1ct in total, set in platinum, typically cost well over £1,000 on the UK high street. Our moissanite studs in 925 sterling silver are £35 a pair for 5mm (the size of a 0.5ct diamond) and £45 for 6.5mm (the size of a 1ct diamond).
At a glance
| Moissanite | Diamond | |
|---|---|---|
| Fire (dispersion) | 0.104 | 0.044 |
| Brilliance (refractive index) | 2.65–2.69 | 2.42 |
| Hardness (Mohs) | 9.25 | 10 |
| Origin | Lab-created | Mined or lab-grown |
Is moissanite right for you?
Choose moissanite if you want lots of sparkle, a stone made for daily wear, and a price that doesn't make you nervous to wear it. Choose diamond if the name and tradition matter most to you.
See our moissanite studs, from £35, gift-boxed, with free tracked UK delivery and 30-day returns.