Lab-grown vs natural diamonds: price, resale and how to tell

Short answer

A laboratory-grown diamond is diamond in every material sense: the same carbon crystal, hardness and sparkle as a mined stone, made in weeks rather than formed over billions of years. It costs a fraction of a comparable natural diamond, and wholesale prices have fallen by about 90% since 2018, so expect little resale value. Choose laboratory-grown for size and budget; choose natural if long-term value or rarity matters. Always check the certificate.

Reviewed by the Nuvinty editorial team

Last checked 4 October 2026 · sources · Nuvinty is an independent affiliate aggregator — we don't sell, authenticate, ship or handle returns.

What is a lab-grown diamond?

A laboratory-grown diamond (often shortened to lab-grown) is carbon crystallised in a factory rather than in the earth. GIA, the US gemmological institute, says lab-grown diamonds have the same chemical, physical and optical properties as natural diamonds (GIA). It is not a simulant.

There are two growth methods (GIA, Gems & Gemology, summer 2024):

GIA reports that CVD stones now make up most of the lab-grown diamonds it sees, and that most are given a post-growth HPHT treatment to improve their colour. Neither method makes a better or worse diamond on its own; the grading of the individual stone matters more.

Simulants are different. Cubic zirconia and moissanite only look like diamond. GIA notes cubic zirconia is 8.5 on the Mohs hardness scale, scratches more easily and has less brilliance; moissanite is 9.25, shows more than twice the fire (rainbow flashes) of diamond and is doubly refractive. Diamond, natural or laboratory-grown, is 10 (GIA).

HPHT (high pressure, high temperature): a diamond seed sits in a press with carbon and a metal catalyst at roughly 5 to 6 GPa and 1,300 to 1,600°C, mimicking conditions deep underground.
CVD (chemical vapour deposition): carbon-rich gas is broken down in a vacuum chamber, usually with microwaves, and builds up layer by layer on a diamond seed.

How big is the price gap in 2025–26?

Very large, and it has widened as laboratory-grown prices have fallen.

UK shop prices (checked 4 October 2026): Goldsmiths listed 52 laboratory-grown rings from about £1,000, including 1.50ct total-weight platinum solitaires at £2,750, and laboratory-grown studs from £850 for 1.00ct total weight in 9ct white gold (Goldsmiths rings, Goldsmiths earrings). Retail prices change often, so compare like for like on carat, colour, clarity, cut and metal.

Wholesale collapse: when De Beers announced the closure of its Lightbox laboratory-grown brand in May 2025, it said wholesale prices had fallen about 90% since Lightbox launched in 2018 (Rapaport, 8 May 2025). Lightbox had launched with fixed per-carat pricing.
Still falling in 2026: analyst Edahn Golan's wholesale index was down 96% since 2018 by Q1 2026, with a 3-carat D VVS round quoted at $126 per carat wholesale, 30% cheaper than in 2025 (JCK, 10 August 2026).
Retail margins stayed high: in the same report, analyst Paul Zimnisky found retailers still marking laboratory-grown stones up by more than 80% above wholesale in 2026. In 2025 he put retail margins at 80 to 90% for laboratory-grown versus 20 to 40% for natural (JCK, 19 March 2025).
Versus natural: in mid-2024 Zimnisky said laboratory-grown stones often sold at a 90% or greater discount to natural equivalents (JCK, 28 June 2024).
Natural prices fell too: Rapaport's RapNet Diamond Index for 1-carat natural diamonds fell 9.9% in 2025, 0.50-carat fell 26% and 0.30-carat fell 20.3%, while 3-carat edged up 0.3% (Rapaport, January 2026).

Do lab-grown diamonds have resale value?

Very little. Because laboratory-grown diamonds can be made in quantity and production costs keep falling, a used stone competes with ever-cheaper new ones. JCK reported a dealer telling a client who had paid $25,000 for a five-carat laboratory-grown ring that there is no resale value for laboratory-grown diamonds (JCK, August 2026).

The UK advertising regulator treats this as material. In its May 2026 ruling against a jeweller's ads, the ASA said differences in future value between natural and synthetic diamonds are information consumers need (ASA, 13 May 2026).

Natural diamonds are not an investment either. You will usually sell below what you paid at retail, because the retailer's margin and VAT are not recoverable. Natural prices themselves have also fallen, especially for smaller stones in 2025 (Rapaport). Larger, rarer natural stones have held up better.

Buy either type because you want to wear it, not to make money.

How to tell them apart, and what the seller must say

You cannot tell by eye. Even jewellers rely on laboratory equipment, and GIA notes no single screening tool reliably identifies every laboratory-grown stone, particularly very small ones (GIA).

Check the paperwork:

UK rules on wording:

Nuvinty does not sell, authenticate or grade stones. Rely on the retailer's description and the independent certificate, and ask the retailer directly if either is unclear.

GIA: since 1 October 2025 GIA issues a Laboratory-Grown Diamond Quality Assessment that rates stones as Premium or Standard instead of giving natural-diamond colour and clarity grades. Premium needs D colour, VVS clarity or better and excellent polish and symmetry. Each stone is laser-inscribed on the girdle with "Laboratory-Grown" and its report number (GIA).
IGI: IGI laboratory-grown reports carry an "LG" prefix on the report number, which is laser-inscribed on the girdle, and can be checked on IGI's website (IGI).; Match the inscription and report number to the stone and look the report up on the lab's own site before you pay.; The National Association of Jewellers' Diamond Terminology Guideline, which carries Primary Authority Assured Advice status with Trading Standards, says "diamond" on its own always means natural. Laboratory-made stones must be called "synthetic", "laboratory-grown" or "laboratory-created". It advises against abbreviations such as "lab-grown", and against "cultured", "real", "genuine" or "precious" for synthetic stones (NAJ, 2023).; The ASA's guidance (October 2025) says ads must use a clear, prominent qualifier throughout, must not call laboratory-grown stones "real diamonds", and that claims such as "carbon neutral diamond" do not tell shoppers the stone's origin (ASA). In May 2026 it upheld complaints against two jewellers whose ads said "diamonds" without a qualifier (ASA ruling).; For context, the US FTC requires "laboratory-grown", "laboratory-created" or "[manufacturer]-created" immediately before "diamond" and as conspicuous, and says "cultured" needs a clear qualifier (FTC).

Ethics and environment: an honest view

Neither option is automatically "clean". The evidence is thinner and more partisan than marketing on both sides suggests.

Laboratory-grown: growing diamond takes a lot of electricity. Most production is in China and India, where much of the grid is coal-powered, so the footprint depends heavily on where and how a stone was made (ABC News, 2024). The often-quoted study showing laboratory-grown far greener (Frost & Sullivan, 2014) used data from one producer and was produced for a laboratory-grown trade association (JCK, 2019). Studies funded by miners have reached the opposite conclusion, so treat both with caution.

Regulators push back on vague green claims. The FTC warned eight companies in 2019 that unqualified terms like "eco-friendly" and "sustainable" are very hard to substantiate (JCK), and the ASA has said "carbon neutral diamond" is not an acceptable way to describe a laboratory-grown stone (ASA). A laboratory-grown diamond does avoid mining's land disturbance (ABC News).

Natural: the Kimberley Process certifies rough diamonds against a narrow definition of conflict diamonds: stones used by rebel movements to fund war against legitimate governments (Kimberley Process). It does not cover abuses by governments, labour rights or environmental harm (International Peace Institute, 2023). Human Rights Watch documented abuses by security forces in Zimbabwe's Marange fields that fell outside that definition (HRW, 2012).

Mining also supports economies. Diamonds make up about 80% of Botswana's exports, and falling demand linked partly to laboratory-grown stones has hit its public finances hard (Fortune, November 2025, Christian Science Monitor, March 2026).

If ethics matter to you, ask any seller for specific, checkable origin information rather than relying on a label.

Which should you choose?

Engagement ring on a set budget: laboratory-grown buys a much larger or higher-graded stone for the money. Accept that its resale value is close to nil and that the same stone will probably cost less next year.
Heirloom, rarity or some value retention: natural is the better fit, ideally a well-cut stone with a GIA or similar report. Do not expect to sell at the price you paid.; Earrings, tennis bracelets and fashion pieces: laboratory-grown makes strong sense. These are rarely resold, and laboratory-grown studs are now within reach of everyday jewellery budgets.
Pre-loved natural: buying second-hand can sidestep much of the retail markup. Check the certificate matches the stone.
Whatever you buy: confirm the seller's description uses "laboratory-grown", "laboratory-created" or "synthetic" where relevant, get the report number, and verify it with the lab.

Common questions

Is a lab-grown diamond a real diamond?

Yes, in material terms. GIA says laboratory-grown diamonds have the same chemical, physical and optical properties as natural ones. UK trade guidance still requires sellers to call them "synthetic", "laboratory-grown" or "laboratory-created", not simply "diamond" or "real diamond".

Can a jeweller tell a lab-grown diamond from a natural one?

Not by eye. Identification needs specialist equipment, and GIA notes no single screening device catches every laboratory-grown stone. The reliable check is the grading report and the matching laser inscription on the girdle.

How much cheaper are lab-grown diamonds?

Much cheaper. Analyst Paul Zimnisky said in 2024 that laboratory-grown stones often sold at a 90% or greater discount to natural equivalents, and wholesale prices have kept falling since. In October 2026 Goldsmiths listed laboratory-grown 1.00ct total-weight studs from £850.

Do lab-grown diamonds hold their value?

No. Prices for new stones keep falling, so used ones have little resale value. Natural diamonds also resell below the retail price, but there is an established second-hand market for them.

Is moissanite a lab-grown diamond?

No. Moissanite is silicon carbide, a different material that imitates diamond. It is slightly softer (9.25 on the Mohs scale against 10 for diamond) and shows more rainbow fire.

Are lab-grown diamonds better for the environment?

Not automatically. Production is energy-intensive and largely based in coal-heavy grids in China and India. They avoid mining's land impact, but footprint depends on the producer. Be wary of unqualified "eco-friendly" claims, which UK and US regulators have challenged.

What does GIA's Premium or Standard grade mean?

Since 1 October 2025 GIA rates laboratory-grown diamonds as Premium (D colour, VVS clarity or better, excellent finish) or Standard (E to J colour, at least VS clarity, very good finish) instead of giving full natural-style colour and clarity grades.

Where this comes from

Every figure and rule above is taken from the sources below. Rules, fees and brand practices change — check the source before you rely on it for a specific purchase.

Put it into practice

Buying guides and live listings for the models this applies to most:

Pre-owned Van Cleef & Arpels Alhambra Pre-owned Bulgari B.zero1 Pre-owned Cartier Love Bracelet Pre-owned Chopard Happy Diamonds Pre-owned Tiffany Return to Tiffany Pre-owned Boucheron Quatre