Let us clear up the wording first, because the question is usually asked as “real diamonds versus lab-grown diamonds” and that phrasing contains a mistake.

A lab-grown diamond is a real diamond. The correct comparison is lab-grown versus natural — or mined. “Real versus fake” belongs to a different conversation entirely, the one about cubic zirconia and moissanite, which are different materials that merely look like diamond.

With that settled, here is what genuinely separates the two, and what does not.

What is identical

Both are pure carbon, crystallised in the diamond lattice — every atom bonded to four neighbours in a rigid three-dimensional structure. Because the material and the structure are the same, so is everything that follows from them:

• Hardness — 10 on the Mohs scale for both. Neither scratches more easily than the other.
• Sparkle — the same refractive index and dispersion, so the same brilliance and fire from the same cut.
• Density and chemistry — indistinguishable.
• Grading — the same cut, colour, clarity and carat scales, assessed by the same laboratories.
• Durability in wear — both can be resized, repolished, retipped and cleaned identically, and both will outlast you.

You cannot tell them apart by looking, and neither can a jeweller with a loupe in most cases. A standard diamond tester reads both simply as “diamond”.

What is genuinely different

1. Origin and time

This is the only difference that is truly fundamental. Natural diamonds formed roughly 150 kilometres beneath the surface over timescales usually described in the hundreds of millions to billions of years, then were carried up by volcanic activity.

Lab-grown diamonds are grown in weeks in a controlled chamber, either by HPHT (recreating mantle-like pressure and heat) or CVD (building the crystal layer by layer from carbon-rich gas). We explain both in detail in how lab-grown diamonds are made.

2. Price

The largest practical difference. Lab-grown diamonds cost substantially less than natural stones of comparable size and quality. We will not quote a percentage, because the gap moves constantly and any figure would be out of date by the time you read it — but it is large enough to change what you can buy, not just what you pay.

The reason is supply. Natural diamond supply is fixed by what geology produced and what is economic to extract. Lab-grown supply responds to demand and to improving technology, and prices have fallen accordingly.

What that means in practice: for a budget that would buy a modest natural stone with compromises on clarity or colour, you can typically have a larger, cleaner, better-cut lab-grown diamond with none of them.

3. Resale and value retention

Here is the honest part that many sellers skate over.

Lab-grown diamonds hold very little resale value. If you sell one second-hand you should expect a small fraction of what you paid. That is worth knowing before you buy.

But it deserves context. Natural diamonds are also poor at holding value — the gap between retail price and what a shop will pay you for a used stone has always been wide, because retail includes cutting, certification, setting, insurance, premises and profit. Neither is an investment. Jewellery is something you buy to wear.

The difference is that lab-grown prices have been falling as production has scaled, which adds a second downward pressure. If resale genuinely matters to you, buy neither and buy something else. If you are buying a ring to wear for forty years, it is close to irrelevant.

4. Inclusion types

Both contain inclusions and both are graded on the same clarity scale, but the features differ slightly. Natural diamonds may contain mineral crystals from the mantle. HPHT-grown stones can contain tiny metallic flux inclusions from the catalyst; CVD-grown stones can show faint internal graining. These are how a laboratory begins to tell the two apart.

5. Certification wording

A grading report for a lab-grown diamond states its origin plainly — “laboratory-grown” — and the growth method. The stone is normally laser-inscribed on the girdle with the report number and wording identifying it as lab-grown. This is required, and it is a good thing: origin is documented rather than assumed.

Side by side

	Lab-grown diamond	Natural diamond
Material	Pure carbon, diamond lattice	Pure carbon, diamond lattice
Hardness	Mohs 10	Mohs 10
Sparkle	Identical for the same cut	Identical for the same cut
Formed over	Weeks	Hundreds of millions of years
Price for the same specification	Substantially lower	Substantially higher
Resale	Low	Low, but generally higher than lab-grown
Supply	Made to demand	Limited by geology
Certification	Same labs, origin stated	Same labs
Tests as diamond	Yes	Yes

The ethical and environmental question, honestly

Many people choose lab-grown for ethical reasons, and there is a real case — but it deserves a straight answer rather than a slogan.

The strong point in favour. A lab-grown diamond has a fully traceable origin. You know which facility produced it. There is no possibility of it having funded conflict, and no question of mining-related land disturbance or displacement, because no ground was opened.

The honest caveat. Growing diamonds is energy-intensive. Both HPHT and CVD run at very high temperatures for weeks. Whether that carries a smaller footprint than mining a comparable stone depends heavily on the electricity source powering the facility. Blanket claims in either direction — from either side of the industry — should be treated with caution, and figures you see quoted online frequently originate from marketing rather than independent measurement.

It is also fair to say that diamond mining supports employment and public revenue in several countries, and that the responsible answer is not “mining is always bad” but “know where your stone came from”. With lab-grown, you can.

Which should you buy?

A simple way to decide.

Choose lab-grown if you want the largest and best-quality stone your budget allows; you want documented origin; you like the idea of no mining; or you would rather spend the difference on the setting, the honeymoon, or nothing at all.

Choose natural if the geological rarity and age of the stone is emotionally important to you; you are matching or replacing a stone in an heirloom piece; or you place weight on the slightly stronger second-hand market despite both being poor value on resale.

There is no wrong answer. There is only the answer that fits what you actually care about.

Frequently asked questions

Are lab-grown diamonds fake?

No. They are chemically, physically and optically diamond. “Fake” describes simulants such as cubic zirconia and moissanite, which are entirely different materials.

Will people be able to tell?

Not by looking, and not with a standard tester. Confirming origin requires laboratory equipment or reading the laser inscription on the girdle under magnification.

Do lab-grown diamonds get cloudy over time?

No. This myth persists but has no basis. Diamond is diamond; it does not degrade, discolour or lose sparkle. What looks like cloudiness is a film of soap and skin oil, and it washes off.

Can I insure a lab-grown diamond?

Yes, in the normal way. Your insurer will want the grading certificate and a valuation. Cover works exactly as it does for a natural stone.

Do lab-grown diamonds come with certificates?

The good ones do. Every centre stone we sell comes with a free IGI certificate stating the four Cs and confirming the stone is laboratory-grown.

Have a look at what the difference buys

Every ring we make uses an untreated, certificated lab-grown centre stone, hand-made into solid gold or platinum in North Harrow, London. To see what the price difference means in practice, compare the Solitaire Round Cut Engagement Ring in White Gold at £563, the Three Stone Emerald Cut Engagement Ring at £1,017 and the Halo Marquise Cut Engagement Ring in White Gold at £1,143 — all correct at the time of writing.

Or browse the full engagement ring collection. Free insured UK delivery, 30-day returns, and bespoke design at no extra design cost if you have something particular in mind.

More guides on this topic

• Can Lab-Grown Diamonds Get Wet? Showers, Swimming and Daily Wear
• Are Lab-Grown Diamonds Better Than Mined Diamonds?
• Are Lab-Grown Diamonds Fake? The Honest Answer
• Who Has the Best Lab-Grown Diamonds? How to Judge Any Seller