Put a moissanite and a diamond of the same size next to each other in daylight and most people can't tell which is which. Move them under a spotlight, though, and you'll notice the moissanite throws more color. That's the whole difference in one sentence. Here's what's behind it, and how to choose based on the look you want.
Moissanite vs diamond: the numbers behind the sparkle
Sparkle comes from three things: how much a stone bends light (brilliance), how much it splits light into colors (fire), and how cleanly it's cut.
| Moissanite | Diamond | |
|---|---|---|
| Refractive index (brilliance) | 2.65 to 2.69 | 2.42 |
| Dispersion (fire) | 0.104 | 0.044 |
| Hardness (Mohs) | 9.25 | 10 |
A higher refractive index means more light comes back to your eye, so moissanite reads as very bright. Its dispersion is more than twice a diamond's, which is why it flashes rainbow colors, especially in larger stones.
What you'll actually see in real life
- Indoors, in soft light: both look white and bright. Very hard to tell apart.
- In direct sun or under spotlights: moissanite shows more colored flashes. A diamond shows more white sparkle with some color.
- In small stones (under 1 carat): the difference almost disappears. This is why a moissanite tennis bracelet or eternity band looks like diamond to nearly everyone.
- In large stones (2 carats and up): the extra fire becomes noticeable. Some people love it, some prefer a calmer look.
Does moissanite look fake?
No. Fake-looking jewelry usually comes from glass or cubic zirconia, which scratch, cloud up and lose their shine over time. Moissanite keeps its brilliance for life because it's nearly as hard as diamond. If your moissanite ever looks dull, it's a film of oil or lotion, and it comes off in five minutes. Our guide on how to clean moissanite walks you through it.
Moissanite or diamond: how to choose
- Choose moissanite if you want a bigger look for the budget, maximum sparkle, and a stone you can wear every day without worrying.
- Choose a diamond if the specific stone and its resale story matter more to you than size or sparkle.
Many women end up with both: a diamond they inherited or received, and moissanite pieces they actually wear daily, like stud earrings or a solitaire necklace.
Tips to get the most sparkle from moissanite
- Pick the cut for the effect you want. Round brilliant shows the most fire. Emerald and Asscher cuts give a cleaner, mirror-like flash.
- Want something different? Black moissanite and colored moissanite keep the same hardness with a bolder look.
- Keep it clean. A clean stone always sparkles more than a dusty diamond.
Quick answers
Can a jeweler tell moissanite from diamond? With a magnifier and a moissanite tester, yes. By eye across a table, almost never.
Does moissanite sparkle more than diamond? It has more fire (colored sparkle) and slightly more brilliance. Diamond has a softer, whiter sparkle.
Does moissanite lose its sparkle over time? No. Its optical properties don't change. Read more in our moissanite guide.
See the difference for yourself with our best-selling moissanite pieces.
