Are Lab Grown Diamonds Worth It? The Honest UK Answer (2026)

For most UK buyers, yes: lab grown diamonds are worth it. You get a certified diamond that is chemically and optically identical to a mined stone for typically 60 to 80% less money, which means better colour, better clarity and a better cut for the same budget. The honest caveat is that no diamond, mined or lab grown, is a financial investment, and anyone telling you otherwise is selling something. This guide gives you the seven facts that actually matter, including the ones most jewellers skip.

In this article

• 1. Are lab grown diamonds real diamonds?
• 2. How much cheaper are lab grown diamonds?
• 3. Do lab grown diamonds hold their value?
• 4. What does the saving actually buy you?
• 5. Are they certified and insured like mined diamonds?
• 6. Are lab grown diamonds the ethical choice?
• 7. Will prices keep falling, and does it matter?
• Lab grown vs mined at a glance
• FAQ

1. Are lab grown diamonds real diamonds?

Yes, and this is settled fact, not marketing. A lab grown diamond is pure crystallised carbon with the same hardness (10 on the Mohs scale), the same brilliance and the same fire as a mined diamond. The US Federal Trade Commission removed the word "natural" from its definition of a diamond in 2018, stating that laboratory grown stones have essentially the same optical, physical and chemical properties as mined diamonds.

They even pass standard thermal diamond testers, because they are diamonds. The only reliable way to tell the two apart is specialist laboratory equipment reading microscopic growth patterns, plus the laser inscription on the girdle stating the stone's lab origin. Your eye, and everyone else's, cannot tell the difference.

2. How much cheaper are lab grown diamonds?

Typically 60 to 80% cheaper than a mined diamond of the same carat, colour, clarity and cut, and the gap has widened year on year. In practical UK terms: a budget that stretches to a modest half carat mined stone will comfortably buy a one carat lab grown diamond of superior grade, set in 18ct hallmarked gold, with change left over for the honeymoon fund.

That is the real headline. Not "cheap diamonds", but the same diamond, minus the cost of digging it out of the ground. If you want to see what two perfectly matched lab grown stones make possible, our toi et moi ring guide is a good place to start.

3. Do lab grown diamonds hold their value?

Here is the answer most jewellery blogs bury: no, and neither do mined diamonds. A mined diamond typically resells for somewhere between 20 and 50% of its retail price, and lab grown stones resell for less than that. Buying any diamond as a financial investment is like buying a new car as one: the value drops the moment it leaves the shop, because retail prices include craftsmanship, service, warranties and margin that no second-hand buyer will pay for.

So the honest question is not "which diamond holds its value" but "how much am I comfortable never seeing again". Spend £8,000 on a mined stone and resale might return £2,000 to £4,000 of it. Spend £2,000 on an identical-quality lab grown stone and even a total write-off costs you less than the mined stone's depreciation alone. You are not buying an asset. You are buying a symbol you will wear every day for decades, and paying a fair price for it.

4. What does the saving actually buy you?

Not just a bigger stone. The smarter move is better quality. At mined prices, most UK buyers compromise: a lower colour grade here, a visible inclusion there, a shallower cut to hit a carat target. At lab grown prices those compromises disappear. Every ring in our engagement rings collection is set with a hand-picked lab grown diamond at D colour (the highest grade on the scale), VVS+ clarity and an Ideal cut, the combination that actually determines how a diamond performs in daylight, candlelight and every photograph taken of your left hand for the rest of your life.

5. Are they certified and insured like mined diamonds?

Identically. Reputable laboratories including IGI and GIA grade lab grown diamonds on exactly the same 4Cs scale, with the same scrutiny, and issue a report that states the stone's laboratory origin transparently. Insurers treat a certified lab grown diamond ring the same way they treat a mined one: you insure it for its replacement value, and because that value is lower, the premiums usually are too.

Every Not Mined diamond arrives with its IGI or GIA certificate, so what you are buying is documented, graded and verifiable, not taken on trust.

6. Are lab grown diamonds the ethical choice?

On the mining question, clearly yes: no earth moved, no mining communities put at risk, no ambiguity about where the stone came from. That is why we called the company Not Mined.

But we will not greenwash you. Growing diamonds takes serious energy, and the footprint of a lab grown stone depends on how the growers power their reactors. Blanket claims like "100% sustainable" are exactly the kind of marketing regulators have warned the industry about. The fair statement is this: a lab grown diamond removes mining from the equation entirely and gives you a fully traceable origin, which is more than any mined stone can honestly claim.

7. Will prices keep falling, and does it matter?

Lab grown prices have fallen substantially over the past decade and may continue to drift down as production scales. If you are buying a diamond to resell later, that matters, and you should not buy one at all (see fact 3). If you are buying a ring to propose with, it matters about as much as the falling price of televisions mattered to the film you watched last night.

You are exchanging money for a certified, permanent, beautiful object with a job to do for the next fifty years. Buy it for that, at a price that leaves your savings intact, and it is unambiguously worth it.

Lab grown vs mined at a glance

	Lab grown diamond	Mined diamond
Chemical composition	Pure carbon, identical	Pure carbon, identical
Hardness	10 on the Mohs scale	10 on the Mohs scale
Certification	IGI / GIA, same 4Cs	IGI / GIA, same 4Cs
Typical price (same grade)	60 to 80% less	Benchmark
Resale value	Low	Low (typically 20 to 50% of retail)
Origin	Traceable, no mining	Varies by source

Frequently asked questions

Are lab grown diamonds cheaper than natural diamonds?

Yes, typically 60 to 80% cheaper for a stone of identical carat, colour, clarity and cut. The gap has widened as production has scaled, which is why over half of new engagement ring centre stones bought in the US are now lab grown.

Do lab grown diamonds test as real diamonds?

Yes. Standard thermal diamond testers identify lab grown stones as diamonds every time, because they are. Simulants like cubic zirconia and moissanite fail those tests; lab grown diamonds do not.

Do lab grown diamonds get cloudy or fade over time?

No. A lab grown diamond is as hard and as chemically stable as a mined one, so it will not cloud, yellow or dull. If it ever looks hazy, it is dirty: warm water, a drop of washing-up liquid and a soft brush restore it.

Can a jeweller tell a lab grown diamond from a mined one?

Not by eye. Even trained gemmologists need specialist laboratory equipment to detect the microscopic growth-pattern differences, and most certified lab grown stones carry a laser inscription on the girdle stating their origin.

Is a lab grown diamond good for an engagement ring?

Yes. It is a real diamond with identical durability and sparkle, certified on the same scale, at a fraction of the price. That is why the majority of new engagement ring buyers now choose one. View engagement rings →