If you're shopping for a tennis chain, you'll run into both of these, and the sales copy on most sites won't tell you the difference honestly. So here it is.
Lab-grown diamonds and moissanite are both real, both beautiful, and both dramatically less expensive than mined diamonds. They are not the same material, and they don't look the same in person.
What each one actually is
Lab-grown diamond is diamond. Chemically, physically and optically identical to mined diamond — same carbon crystal structure, same properties — grown in a laboratory rather than pulled out of the ground. Gemologically it is a diamond, and standard grading labs certify it as one.
Moissanite is silicon carbide. It's a genuinely different mineral that happens to be transparent, extremely hard and highly brilliant. It occurs naturally in meteorite fragments, but essentially all jewelry moissanite is lab-created.
Neither is a "fake diamond." One is a diamond made a different way. The other is a different stone entirely, and it doesn't pretend otherwise.
Hardness and durability
On the Mohs scale of mineral hardness:
- Diamond (mined or lab-grown): 10 — the hardest known natural material
- Moissanite: approximately 9.25 — one of the hardest materials used in jewelry, behind only diamond
For a tennis chain, both are far harder than anything they'll routinely contact. Neither will scratch from ordinary wear.
Where it matters in practice is long-term facet sharpness on a piece worn constantly for many years. Diamond holds its edges marginally better. It's a genuine difference, but a small one in daily use.
How they look — the actual difference
This is the part that matters, and it gets glossed over.
Diamond disperses light in a way most people read as "white fire" — bright, crisp, with flashes of color that stay subtle. It's the look everyone recognizes.
Moissanite has a higher refractive index and substantially greater dispersion than diamond. Translation: it throws more light, and more colored light. Under direct light — sunlight, spotlights, a phone flash — moissanite produces noticeably more rainbow flash than diamond does.
Whether that's a plus depends entirely on you. Some people love it and choose moissanite specifically for that extra fire. Others find it reads differently from diamond and prefer the more restrained diamond look.
A few practical notes:
- The difference is most visible in larger stones and in direct light. In small stones under indoor light, they look extremely similar.
- On a tennis chain — many small stones in a row — the two are much harder to tell apart than in a single large stone.
- Anyone who tells you moissanite is indistinguishable from diamond in all conditions is overselling. Anyone who tells you it looks obviously fake is also wrong.
Cost
This is the reason both categories exist.
Lab-grown diamond costs a fraction of an equivalent mined diamond, while being the same material. Moissanite costs a fraction of lab-grown diamond.
The gap is meaningful at every size, and it widens as stones get larger. On a tennis chain, where you're paying for a lot of total carat weight, that difference compounds into a very large number.
We're not going to quote figures here because stone pricing moves. Our current lab-grown diamond tennis pieces and moissanite pieces are priced live on the site.
Certification and resale
Lab-grown diamonds are graded by the same major labs that grade mined stones, using the same criteria — cut, color, clarity, carat. Certification is standard on significant stones.
Moissanite is not graded on the diamond scale, because it isn't a diamond. Quality varies by manufacturer, and reputable moissanite is sold by named grade or brand rather than a lab report.
On resale, be realistic about both: lab-grown diamond has stronger secondary-market recognition than moissanite, but neither holds value the way gold does. If resale value is a priority for you, the gold in the chain is where that value lives, not the stones. This is worth thinking about when choosing between a heavier gold setting with fewer stones and a lighter setting with more.
Which should you buy?
Choose lab-grown diamond if: you want it to genuinely be diamond, you care about certification, you prefer the classic diamond look, or you're buying something you intend to keep and pass on.
Choose moissanite if: you want maximum visual impact per dollar, you like the extra fire, or you want a larger overall look than your budget allows in diamond. It's an excellent stone that's poorly served by being described as a substitute.
There's no wrong answer here. We sell both, we wear both, and we'd rather help you pick the one you'll actually be happy with than push you toward the more expensive one.
One thing worth insisting on either way
The setting matters as much as the stone.
A tennis chain lives or dies on prong work. Poorly set stones fall out, and on a chain with hundreds of stones, a bad setting isn't a small problem. Look for even, well-formed prongs, consistent stone spacing, and a chain that flexes smoothly without stiff or twisted sections.
Every tennis piece we carry is inspected before it ships, and we photograph the actual piece you'll receive. See what customers say in our reviews.
Frequently Asked Questions
Is moissanite the same as a lab-grown diamond?
No. Lab-grown diamond is chemically and physically identical to mined diamond. Moissanite is silicon carbide, a different mineral with different optical properties.
Is a lab-grown diamond a real diamond?
Yes. Lab-grown diamonds have the same carbon crystal structure and physical properties as mined diamonds and are certified as diamonds by standard grading laboratories.
Does moissanite sparkle more than diamond?
Moissanite has a higher refractive index and greater dispersion than diamond, so it produces more colored flash, particularly in larger stones and direct light.
Which is harder, moissanite or diamond?
Diamond is a 10 on the Mohs hardness scale and moissanite is approximately 9.25. Both are more than durable enough for everyday jewelry.