Lab-Grown Diamond Jewellery: Questions to Ask Before Buying

Lab-grown diamonds have moved from a curiosity to a mainstream choice, and many buyers now ask about them. This is a neutral guide to help you ask the right questions, whichever way you decide. We sell natural diamond jewellery, and we have written this so that you can make a comparison with confidence.

What is a lab-grown diamond?

A laboratory-grown diamond is made by recreating the conditions in which diamonds form, using methods such as high pressure and high temperature (HPHT) or chemical vapour deposition (CVD). It has the same chemical composition and crystal structure as a natural diamond. It is not an imitation like cubic zirconia.

How does it differ from a natural diamond?

• Origin: natural diamonds form over a very long time deep in the earth. Laboratory-grown stones are made in weeks or months.
• Identification: the two look alike to the eye. Specialised instruments can tell them apart.
• Price: laboratory-grown stones are generally priced well below natural stones of the same size and grades, and prices have been falling.
• Rarity and value perception: natural stones are finite. Laboratory-grown stones can be produced in quantity.

See our balanced comparison in natural vs lab-grown diamonds: what's the real difference?.

Questions to ask the seller

1. Is it natural or laboratory-grown, in writing? It must be disclosed on the invoice and the certificate.
2. Which laboratory graded it, and is the report number verifiable? Reports for laboratory-grown stones state that origin.
3. Is it inscribed? Many laboratory-grown stones carry a laser inscription that identifies them as such.
4. What are the grades? Colour, clarity, cut and carat, as for any diamond.
5. What is the treatment history? Some laboratory-grown stones are treated after growth, and that should be stated.
6. What is the buy-back or exchange policy? This is where the difference is most visible. See can you resell diamond jewellery?.

Price versus value

A lower price is attractive, and for fashion jewellery or a larger look for a smaller budget, many people find it appealing. But because supply can grow and prices have been declining, treat laboratory-grown jewellery as something you buy to wear and enjoy, not as a store of value.

Sustainability claims

Sellers sometimes describe laboratory-grown diamonds as more environmentally friendly. Impacts depend on the energy used in production and on how the stone is sourced. Ask for specific information instead of accepting a general claim. For natural stones, see natural diamonds and sustainability: myths vs facts.

Metal and making still matter

Whatever the stone, the gold or platinum, its hallmark and the making are the same considerations. See BIS hallmark marks explained.

Be wary of

• A seller who will not give origin in writing.
• Unusually low prices with "natural" claims.
• A report from an unfamiliar laboratory with no verification.

Which is right for you?

If you value rarity and the long history of natural stones, natural diamonds are the choice. If a larger look for a lower budget matters more, laboratory-grown deserves a look. Be clear about which you are buying. To see natural stones in person, book an appointment or browse our diamond rings.