Diamond
The incumbent
VS
Moissanite
The challenger with more fire
Diamond vs Moissanite
One is the tradition, the other costs a small fraction and throws more rainbow. Here is the honest split.
Best for tradition and toughness: DiamondBest for budget, by a mile: Moissanite
| Diamond | Moissanite | |
|---|---|---|
| What it is | Crystallized carbon, the classic | Silicon carbide, a different crystal entirely |
| Hardness | 10 on the Mohs scale, the hardest gem | About 9.25, harder than sapphire, fine for daily wear |
| Sparkle | Balanced white light and fire | More rainbow fire; noticeably flashier in sunlight |
| Price | The benchmark | A small fraction of even lab-grown diamond prices |
| Telling them apart | Reads as diamond on a tester | A trained eye can spot the extra fire; most people never notice |
| Resale | Weak to modest | Essentially none |
Pick diamond if
- It has to be a diamond, full stop, and that is a valid preference
- You want the most understated, classic read on the hand
- Heirloom plans are real
Pick moissanite if
- The budget would rather go toward a house, a trip, or a life
- She likes sparkle and does not care about gem taxonomy
- You both enjoy telling people what it is
The disclosure rule
Moissanite is a wonderful stone and a terrible secret. Buy it proudly and say what it is; passing it off as diamond is the only way to lose with it. Most couples who choose it treat the price as the flex.
Where the extra fire shows
Under pinpoint lighting and direct sun, moissanite throws distinctly rainbow flashes where diamond stays whiter. Bigger stones show it more. Some people love the effect, a few find it too much. Look at both in person or on video before deciding.