Are Lab Grown Diamonds Real Diamonds?

Yes. And you can check it yourself in about two minutes, without taking anyone's word for it, including mine.

Pick up the ring. Turn the stone side on. Somewhere around the girdle, the thin band where the top of the stone meets the bottom, there is a laser inscription. On our stones it reads IGI followed by a report number. It is too small to read with your eyes. A 10x loupe will show it, and most jewellers will hand you one across the bench if you ask. Type that number into the IGI report check page and the full grading report comes up: shape, carat, colour, clarity, cut, measurements, and the words "laboratory grown diamond" in the origin field.

That is the whole verification chain. The stone in your hand has a serial number burned into it, the number matches a report held by an independent gemmological laboratory, and the report states both what the stone is and how it was made. Nothing about that process depends on trusting the person selling it to you.

Why a diamond tester reads both as diamond

Walk into any jewellery counter with a lab grown diamond and ask them to test it. The little pen shaped probe will beep and light up green, same as it would for a stone dug out of the ground.

This is not the tester being fooled. Those testers measure thermal conductivity. Diamond moves heat away from a heat source faster than almost any other material on earth, and a lab grown diamond has exactly the same crystal structure doing exactly the same thing. The tester is reading the material correctly. The material is diamond.

The same goes for the other bench tests. Same hardness, 10 on the Mohs scale. Same refractive index at 2.42. Same specific gravity at 3.52. Same behaviour under a polariscope, the same adamantine lustre off a polished facet, the same everything, because it is the same substance: carbon atoms in a cubic lattice.

So what actually is a lab grown diamond

Carbon, crystallised under conditions that copy what happens deep in the earth, run in a machine instead of over a billion years.

There are two production methods. HPHT puts a tiny diamond seed into a press with a carbon source and a metal flux, then applies pressure and heat in the range where diamond, rather than graphite, is the stable form of carbon. CVD puts a seed plate into a vacuum chamber, fills it with a carbon bearing gas, and uses microwaves to break the gas apart so carbon settles onto the seed layer by layer. Both produce diamond. They differ in the growth patterns and trace elements they leave behind, which is exactly how a laboratory identifies them, and we have written up how lab grown diamonds are made if you want the detail.

The finished stone is then cut and polished on the same wheels, by the same cutters, to the same proportions as any other diamond.

The terminology mess, sorted

This is the part that causes most of the confusion, and it is worth being blunt about.

All of these mean the same thing:

• Lab grown diamond
• Lab created diamond
• Laboratory grown diamond
• Man made diamond
• Manufactured diamond
• Engineered diamond
• Synthetic diamond
• Cultured diamond

Eight names, one product. The reason there are eight is that the trade cannot agree on which one sells best. "Synthetic" is the correct technical term in gemmology and has been for decades, but to a shopper it sounds like polyester, so retailers avoid it. "Cultured" was borrowed from the pearl trade to sound gentler, and regulators have generally pushed back on it because it implies a biological process that is not happening. "Lab grown" and "lab created" won the marketing argument, which is why you see them most.

If someone asks you "are man made diamonds real" or "are synthetic diamonds real", they are asking the same question as "are lab grown diamonds real". The answer does not change with the label.

The distinction that actually matters: grown versus simulant

Here is the single most useful thing in this article.

A lab grown diamond is diamond. Same chemistry, same crystal structure, same physical properties.

A diamond simulant is not diamond. It is a different material that has been cut to look like one.

The common simulants are cubic zirconia, moissanite, white sapphire, white topaz, and glass. None of them are carbon. Cubic zirconia is zirconium dioxide. Moissanite is silicon carbide. White sapphire is aluminium oxide. They are all legitimate stones in their own right, moissanite especially, but they are not diamond and no honest seller will tell you otherwise.

The practical differences are real and measurable. Cubic zirconia is around 8 on the Mohs scale and abrades visibly within a couple of years of daily wear. Moissanite is 9.25, holds up beautifully, and throws noticeably more coloured fire than diamond because its dispersion is more than double. White sapphire is 9 and tends to look sleepy rather than bright because its refractive index is much lower.

So when you see a stone advertised as a "lab diamond", check which of those two categories it is actually in. A lab grown diamond comes with a diamond grading report. A simulant does not, because you cannot grade a non diamond on a diamond scale. If a listing uses diamond language, quotes a carat weight without a report, and the price looks impossible, you are almost certainly looking at cubic zirconia.

We sell moissanite and we sell lab grown diamonds, and we label each one as what it is. If you are weighing the two against each other, that comparison is here.

They have to be disclosed, and that is a good thing

Consumer protection regulators in both Australia and the United States take the same basic position: the word "diamond" on its own refers to a mined stone, and a laboratory grown stone must be described in a way that makes its origin immediately clear to a buyer. Terms like "lab grown", "lab created" or "laboratory grown" have to sit right next to the word diamond, in the same size and prominence, not buried in fine print or a footnote.

This applies to advertising, to the tag on the ring, to the invoice, and to what the person behind the counter says out loud.

It cuts both ways, and that is the point. It means nobody can pass a lab grown diamond off as mined at mined prices, and it also means nobody can imply that a properly disclosed lab grown diamond is somehow not a diamond. Both statements are misrepresentations under the same rules.

How anyone tells the difference at all

Not by eye. Not with a loupe. Not with a thermal tester. Not by a jeweller with thirty years at the bench.

Identification happens in a laboratory, using equipment that looks at things you cannot see through a lens: growth structure under deep ultraviolet imaging, strain patterns under crossed polarisers, photoluminescence signatures at cryogenic temperatures, and trace element content. HPHT grown material often carries traces of the metal flux it grew in. CVD material shows a layered growth pattern. Mined material shows the irregular octahedral growth of something that formed over a geological timescale.

Every major laboratory can do this reliably, which is why the origin line on an IGI report is trustworthy. But it takes a room full of instruments, and that tells you something about how identical these stones are in every way a wearer would ever encounter.

Where lab grown and mined genuinely differ

Two places, and neither is the stone itself.

Price. A lab grown diamond costs a fraction of a mined one at the same specification. That gap is the entire commercial reason the category exists.

Resale. This is the unflattering part, so here it is plainly. Lab grown diamonds do not hold value. If you buy one and try to sell it in five years you will be disappointed. In fairness, mined diamonds are also a poor resale proposition for a private seller, because you buy at retail and sell at trade, and the spread is brutal. But lab grown is worse, and falling production costs mean a stone you buy today can be replaced more cheaply next year. Buy one because you want to wear it. Do not buy one as an asset. The full comparison is here.

Everything else, the hardness, the brilliance, the way it looks across a dinner table in candlelight, the way it will look in forty years, is the same.

FAQ

Will a jeweller be able to tell my ring is lab grown?

Not by looking at it, no. They will be able to tell by reading the inscription on the girdle or the report that came with it, which is exactly how it should work. The information is available to anyone who wants it and invisible to everyone who does not.

Do lab grown diamonds get cloudy over time?

No. Diamonds do not cloud. What people are describing is a film of skin oil, soap and hand cream on the underside of the stone, which blocks the light that would otherwise bounce back up through it. Warm water, a drop of dish soap and a soft toothbrush fixes it in a minute.

Is moissanite a lab grown diamond?

No. Moissanite is silicon carbide, a different mineral with different optics. The confusion is understandable because both are grown in a laboratory, but they are not the same material and should never be sold as though they are.

Do lab grown diamonds come with a certificate?

Ours do. Every lab grown diamond we set is IGI certified and laser inscribed on the girdle with its report number, so you can look up the grading yourself at any point.

Can I see one in person before deciding?

Yes. We make everything in our Southbank, Melbourne studio and you can book an appointment to look at stones side by side. If Melbourne is not practical, we do design consultations by video call, and you can browse lab grown diamond engagement rings online first.