How do I check a lab-grown diamond report number is genuine?

ZKZ Editorial TeamMain answer · Product & gemmology desk

Look the number up on the issuing laboratory's own website, then check that every detail matches the stone you have, including the inscription on the girdle where there is one. A matching entry is evidence, not a guarantee.

What the laboratories offer

Fact IGI's Verify Your Report page lets you enter a report number, use an SKU lookup or scan a QR code, and states that the report is an opinion of IGI and not a guarantee, appraisal or warranty.

Fact GIA states that a laboratory-grown diamond assessed under its service has the girdle laser inscribed with the words "Laboratory-Grown" and its GIA report number, and GIA offers a Report Check on its site.

Steps

1. Type the number into the issuing laboratory's site yourself, not through a link from the seller.
2. Compare shape, weight, measurements, colour and clarity with the listing.
3. Ask for the girdle inscription to be photographed or check it with a loupe.
4. Make sure the report describes the stone, not just a similar one.
5. Keep a screenshot of the result.

Our advice If the details differ, or the lab cannot find the number, ask the seller to explain in writing before paying.

It depends Weight and grade can differ slightly if a stone has been re-measured or re-graded, and older reports may be in a different format.

What to do if something does not match

Our advice Do not assume fraud, because typing errors and updated reports are common. Ask the seller for a clear scan of the report, then check the number again. If it still does not match, ask for a refund or a written explanation before you pay. Keep the correspondence, and if you have already paid, contact your payment provider promptly.

Our advice Keep a screenshot of the laboratory result with the date, and store it with the order. If the page changes later, or the seller's listing is removed, you still hold a record of what you checked.

Uncertain We have not verified whether every laboratory offers an online lookup, so check each laboratory separately.

Related reading: What does fluorescence mean on a lab-grown diamond report? · Lab Grown Diamond Certification: IGI, GIA and What to Check

Sources

• IGI, Verify your report
• GIA, Laboratory-grown diamond reports

Fact = stated by the cited source. Our advice = editorial recommendation. Uncertain / it depends = limits of what can be said in general.