If you have been shopping for one of these stones you will have met at least six names for the same thing: lab-grown, lab-created, laboratory-grown, man-made, synthetic, engineered, CVD, HPHT. Some sellers add “cultured” or “cultivated”. A few just say “diamond”.

They are not all equally correct, and the differences are not just style. Some of these words are the approved trade terms, some are informal, and some are actively discouraged because they mislead. Here is what each one means and which to use.

The proper names

Internationally, the terminology for these stones is set out in a gemmological standard — ISO 18323 — which the UK trade follows. It recognises three descriptions, and they are interchangeable:

• Laboratory-grown diamond
• Laboratory-created diamond
• Synthetic diamond

All three mean the same stone: a genuine diamond, produced by a controlled process rather than by geology. The standard also requires that the qualifying word always appears with “diamond” — you cannot drop it and simply say “diamond” if the stone is laboratory-grown.

“Lab-grown diamond” and “lab-created diamond” are the everyday shortenings of the first two, and they are what most shops and most customers actually say. We use “lab-grown” throughout our site because it is the clearest for someone who has never bought a diamond before.

A note on “synthetic”

“Synthetic” is technically correct and is the term you will see in gemmological literature. In gemmology it means “man-made version of a material that also occurs naturally” — the opposite of an imitation.

The problem is what the word does in ordinary English, where “synthetic” suggests plastic, artificial, not the real thing. Because of that, most retailers avoid it even though it is accurate. If you see it on a laboratory report, it is not a warning sign.

Names that are not approved

Term	Status	Why
Cultured diamond	Discouraged	Borrows the language of cultured pearls, where a natural organism does the work. Misleading here.
Cultivated diamond	Discouraged	Same problem — implies a biological or agricultural process.
Real / genuine / precious diamond	Not permitted as a substitute	These words are used to distinguish diamond from imitations. They cannot replace the required disclosure.
Just “diamond”	Not permitted	Origin must be disclosed. Omitting it is misdescription.
Man-made diamond	Informal but honest	Widely understood, not one of the standard terms. Harmless in conversation.
Engineered / created diamond	Marketing language	Vague. “Created” on its own is not a full disclosure.

The rule underneath all of this is simple and worth remembering when you read any listing: the origin must be stated plainly, next to the word diamond, in equal prominence. A footnote in small print at the bottom of a page does not count.

Names that mean something completely different

These are the ones that cause real confusion, because they describe stones that are not diamond at all:

• Diamond simulant — anything that looks like diamond but is a different material.
• Cubic zirconia (CZ) — zirconium dioxide. Much softer, much cheaper, not diamond.
• Moissanite — silicon carbide. A genuine gemstone in its own right, but not diamond. We explain the differences in is a lab-grown diamond a moissanite.
• White sapphire, white topaz, glass — all simulants.
• “Diamond hybrid”, “diamond veneer”, “diamond-like” — invented marketing terms, usually for a coated simulant. Treat with suspicion.

The distinction is the whole point. A lab-grown diamond is diamond — same carbon, same lattice, same hardness of 10 on the Mohs scale, same sparkle, graded on the same four Cs by the same laboratories. A simulant only resembles one.

Growth method names: CVD and HPHT

You will also see stones described as “CVD diamond” or “HPHT diamond”. These are not alternative names for lab-grown — they identify how the crystal was produced.

• HPHT — High Pressure, High Temperature. Recreates mantle-like conditions with a press.
• CVD — Chemical Vapour Deposition. Builds the crystal in layers from carbon-rich gas in a vacuum chamber.

Both produce real diamond and both appear on certificates. Neither is a quality ranking. If you want the detail, read how lab-grown diamonds are made.

What it says on the certificate

A grading report is where the terminology becomes precise, and it is the document to trust over any product description.

An IGI report for one of these stones will be headed as a laboratory-grown diamond report, state the growth method, and record cut, colour, clarity and carat weight on the same scales used for mined stones. Any post-growth treatment, such as HPHT colour improvement of a CVD stone, is noted.

The stone itself is normally laser-inscribed on the girdle — the thin outer rim — with the report number and wording such as “LAB GROWN” or “LG”. A jeweller can read it under magnification in a minute, and you can check the number against the laboratory’s own free online database.

Every centre stone we sell comes with a free IGI certificate for exactly this reason. Whether that is the Solitaire Emerald Cut Engagement Ring at £672 or the Three Stone Cushion Cut Engagement Ring at £957 (prices correct at the time of writing), the paperwork names the stone properly.

How to read a listing

A few practical tests when you are comparing sellers:

1. Is the origin stated in the product title or the first line? Not buried in a specification table three scrolls down.
2. Does it name a laboratory and give a report number you can check? A seller’s own in-house “certificate” is not independent.
3. Are the words vague? “Created”, “engineered” and “diamond hybrid” without further explanation usually mean someone is hoping you will not ask.
4. Does the price make sense? A stone priced far below every comparable lab-grown diamond is more likely to be a simulant than a bargain.

Frequently asked questions

Is “lab-grown diamond” or “lab-created diamond” more correct?

Both are fine and mean the same thing. “Grown” arguably describes the process better, since a crystal genuinely grows outward from a seed.

Why do some sellers say “synthetic”?

Because it is the formal gemmological term. It carries no negative meaning in the trade, though most retailers avoid it because customers read it as “artificial”.

Can a shop legally call it just a “diamond”?

No. Origin must be disclosed clearly and prominently wherever the stone is described or offered for sale. Leaving it out is misdescription.

Is a lab-grown diamond a “real” diamond?

Yes — it is real diamond. But “real diamond” is not an acceptable substitute for stating that it is laboratory-grown, because that phrase is used to separate diamond from imitations, not to describe origin.

What should I say when someone asks about my ring?

“It’s a lab-grown diamond” covers it perfectly, and most people now know exactly what that means. There is nothing to apologise for: it is a real diamond with a documented origin and a certificate to prove it.

Have a browse

Everything we make is set with an untreated lab-grown diamond, certificated free by IGI, hand-made in solid gold or platinum in North Harrow, London, with free insured UK delivery and 30-day returns.

Browse the engagement rings or the wedding rings, and read lab-grown versus natural diamonds if you are weighing up the two.