Are Lab-Grown Diamonds Fake? Separating Myth From Fact

Quick Answer No, lab-grown diamonds are not fake. They are chemically, physically, and optically identical to natural diamonds, graded by the same GIA and IGI standards. They cost 60–80% less because they take weeks to produce rather than over a billion years to form underground — not because they're a lesser material.

"Are lab diamonds fake?" is one of the most common questions we hear, and it's a reasonable one — the name itself invites suspicion. Here's the actual answer, without the marketing spin from either side of the debate.

No, They're Not Fake — Here's the Actual Distinction

A fake diamond is a simulant: cubic zirconia, moissanite, or glass, materials that look similar to a diamond but have entirely different chemical composition, hardness, and optical properties. A lab-grown diamond is not a simulant. It is pure crystallised carbon, identical in every measurable way to a natural diamond — same hardness (10 on the Mohs scale), same refractive index, same fire and brilliance. The only difference is where the carbon crystallised: underground over more than a billion years, or in a controlled lab environment over several weeks.

Both are graded by the same independent laboratories — GIA and IGI — using the same cut, colour, clarity, and carat criteria. A lab-grown diamond's certificate looks the same as a natural one's, because it's measuring the same physical properties.

Why Are Lab Diamonds Cheaper, Then?

If the material is identical, the price difference comes down entirely to production cost and time, not quality. A natural diamond requires geological conditions that took over a billion years to occur, plus the cost of locating, extracting, and processing rough diamond from the ground — mining infrastructure, exploration, and the simple rarity of viable deposits all feed into the price. A lab-grown diamond is produced in weeks using one of two established methods (HPHT or CVD), at a fraction of the cost and without geological luck being part of the equation.

This gap has widened further since 2020 as lab-grown production has scaled globally, pushing prices down consistently. There's no structural reason to expect that trend to reverse — if anything, the gap is likely to continue widening as production efficiency improves.

Can You Tell Them Apart?

Not with the naked eye, a jeweller's loupe, or standard retail testing equipment. Only specialist gemological laboratory equipment — typically analysing growth pattern characteristics invisible to standard tools — can reliably distinguish origin. Most lab-grown diamonds also carry a laser inscription on the girdle stating their origin, invisible without magnification, which exists for transparency rather than because the stone needs to be flagged as inferior.

Do Lab Diamonds Hold Value?

This is the one area where the comparison genuinely favours natural: lab-grown diamond prices have fallen significantly since 2020 as production has scaled, and are likely to continue falling, which affects resale value more than it affects a natural stone. For a ring that will be worn rather than resold — which describes the overwhelming majority of engagement rings — this matters less in practice than it might appear, but it's worth knowing honestly rather than glossing over.

So Which Should You Choose?

Neither is objectively better. If maximising size and grade within a fixed budget is the priority, lab-grown is the clear, rational choice — not a compromise. If geological rarity and long-term value retention matter more to you, natural is the right call. We present both honestly at every consultation and give an unbiased view based on what you've told us matters. See our full natural vs lab-grown comparison for the complete breakdown.

Frequently Asked Questions

Are lab-grown diamonds fake diamonds? No. They are real diamonds — chemically, physically, and optically identical to natural diamonds. A fake diamond would be a simulant like cubic zirconia or moissanite, which lab-grown diamonds are not.

Why are lab-grown diamonds so much cheaper than natural? Production cost and time, not quality. Natural diamonds require geological processes over a billion years plus expensive mining; lab-grown diamonds are produced in weeks in a controlled environment.

Can a jeweller tell if a diamond is lab-grown just by looking at it? No. Specialist gemological equipment is required to reliably distinguish origin — it isn't visible to the naked eye or under a standard loupe.

Do lab-grown diamonds hold their value? Less well than natural diamonds, as lab-grown prices have fallen significantly since 2020 due to scaling production. This matters more for resale than for a ring intended to be worn long-term.

Last reviewed: July 2026 · À Vie Diamonds