Is moissanite a real diamond?

No. Moissanite is silicon carbide, a separate gemstone that resembles a diamond. A lab-grown diamond, by contrast, is a real diamond — identical in chemistry and optics to a mined one.

Can you tell moissanite from a diamond?

Often, yes. Moissanite throws more colourful rainbow fire, which becomes easier to spot in larger stones. Diamonds — mined or lab-grown — show a more balanced white brilliance.

Is moissanite or lab-grown diamond better?

It depends on your goal. Moissanite is cheaper; a lab-grown diamond is an actual diamond with diamond hardness, diamond sparkle and a graded certificate. For a forever ring, most people who want a diamond choose lab-grown.

Does moissanite pass a diamond tester?

Older thermal testers can read moissanite as diamond because both conduct heat. Modern dual testers that also measure electrical conductivity tell the two apart reliably.

Is moissanite cheaper than a lab-grown diamond?

Yes, usually. But the step up to a lab-grown diamond buys you a genuine diamond rather than a simulant — which is why many couples choose to spend the difference.

Moissanite vs Lab-Grown Diamond

An honest comparison — from a house that builds with lab-grown diamonds, and will tell you exactly how the two differ.

The one fact that settles most of this debate: a lab-grown diamond is a diamond; moissanite is not. They can look similar across a room, but they are different materials — with different sparkle, different hardness, and different price. We build only with lab-grown diamonds, not moissanite, but you deserve a straight answer on both.

The Montare standard (our floor, not our ceiling): every diamond is lab-grown, D–E colour, VVS1–VVS2 clarity, Triple Excellent cut with ideal table & depth, IGI certified, and 3 carat minimum. Made to order in Toronto.

Are they the same thing?

No. A lab-grown diamond is pure crystallised carbon — chemically and optically identical to a mined diamond, graded on the same 4Cs and certified by IGI or GIA. Moissanite is silicon carbide (SiC), a different mineral first discovered in a meteorite and now grown in a lab. It is a beautiful stone, but it is a diamond simulant — not a diamond.

The real differences

	Lab-Grown Diamond	Moissanite
What it is	A real diamond (carbon)	Silicon carbide — a diamond look-alike
Hardness (Mohs)	10 — the hardest known	9.25 — very hard, but softer
Sparkle	Balanced white brilliance with subtle fire	Extra colourful fire, stronger in larger sizes
Certification	IGI / GIA, graded on the 4Cs	Not graded on the diamond 4Cs
Price (same size)	More than moissanite, a fraction of mined	The least expensive option
Resale / upgrade	A genuine diamond asset; Montare lifetime upgrades	Limited resale value

Hardness

Mohs scale, 10 = hardest known

Lab-grown diamond10

Moissanite9.25

Both wear well — but only diamond is the hardest material on earth.

Price, same look

lowest → highest

Moissaniteleast expensive

Lab-growna real diamond, a fraction of mined

Minedscarcity premium

Lab-grown is the middle path: genuine diamond, without the mining markup.

Sparkle: why moissanite looks different

Moissanite bends light more than a diamond (a higher refractive index) and is doubly refractive, so it throws noticeably more coloured, disco-ball flashes — especially above roughly 1.5 carats. Some people love that extra fire; others feel it reads as obviously not-a-diamond. A lab-grown diamond gives the balanced white sparkle most people picture when they imagine a diamond.

Hardness & everyday durability

Both wear well day to day, but diamond is the hardest material on earth at Mohs 10; moissanite sits at 9.25. For a ring worn every day for decades, that edge in hardness matters most at the facet edges over the very long term.

Price: what you are actually comparing

Order of cost, lowest to highest, for the same look: moissanite < lab-grown diamond < mined diamond. Moissanite wins on pure upfront price. Lab-grown wins when you want a real diamond at a fraction of the mined price — the gap that lets Montare hold a 3-carat, VVS, D/E, Triple Excellent floor on every ring.

So which should you choose?

If your priority is the lowest possible price for a diamond-like sparkle, moissanite is a fair choice. If you want an actual diamond — diamond hardness, diamond brilliance, a graded certificate and lasting value — choose lab-grown. That is the only thing we build with, and for most couples comparing the two seriously, it is the one that feels right on the hand.

Frequently asked questions

Is moissanite a real diamond?: No. Moissanite is silicon carbide, a separate gemstone that resembles a diamond. A lab-grown diamond, by contrast, is a real diamond — identical in chemistry and optics to a mined one.
Can you tell moissanite from a diamond?: Often, yes. Moissanite throws more colourful rainbow fire, which becomes easier to spot in larger stones. Diamonds — mined or lab-grown — show a more balanced white brilliance.
Is moissanite or lab-grown diamond better?: It depends on your goal. Moissanite is cheaper; a lab-grown diamond is an actual diamond with diamond hardness, diamond sparkle and a graded certificate. For a forever ring, most people who want a diamond choose lab-grown.
Does moissanite pass a diamond tester?: Older thermal testers can read moissanite as diamond because both conduct heat. Modern dual testers that also measure electrical conductivity tell the two apart reliably.
Is moissanite cheaper than a lab-grown diamond?: Yes, usually. But the step up to a lab-grown diamond buys you a genuine diamond rather than a simulant — which is why many couples choose to spend the difference.

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