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Our Certification

We never sell an uncertified diamond. Here is what the certificates mean.

Why certification matters

A diamond certificate is an independent assessment of a stone's 4Cs — cut, colour, clarity, and carat weight — conducted by a qualified gemologist at an accredited laboratory. It is not issued by the jeweller selling you the ring. It is issued by a third party with no financial interest in making the stone appear better than it is.

Without a certificate, you have only the word of the person selling you the stone. We believe that is insufficient for a purchase of this significance. At Jabour & Co., every diamond we sell — natural or lab-grown — comes with full certification from a recognised international laboratory.

GIA

Gemological Institute of America

1931, Santa Monica, California

The global gold standard for natural diamond certification. GIA created the 4Cs grading system used across the industry. A GIA certificate is the most widely trusted document in the diamond trade.

Used for

Natural diamonds, primarily round brilliant. All GIA-certified stones have a laser-inscribed certificate number on the girdle.

Grading style

Conservative — GIA grades tend to be stricter than some other labs, particularly on colour and clarity.

At Jabour

Our Impérial Collection natural diamonds are exclusively GIA or IGI certified.

IGI

International Gemological Institute

1975, Antwerp, Belgium

The leading certification laboratory for lab-grown diamonds. IGI has grown significantly in prestige and is now widely accepted as the standard for both lab-grown and natural diamonds.

Used for

Lab-grown diamonds and natural diamonds. IGI certifies the vast majority of lab diamonds globally.

Grading style

Slightly less conservative than GIA on natural diamonds. For lab diamonds, IGI is the recognised standard.

At Jabour

Our Clássico lab-grown diamond configurations use IGI certified stones.

HRD

Hoge Raad voor Diamant (Diamond High Council)

1973, Antwerp, Belgium

The European alternative to GIA, particularly respected in Belgium, the Netherlands, and parts of Asia. Highly credible, slightly less ubiquitous than GIA or IGI outside Europe.

Used for

Natural diamonds. HRD certificates are accepted by all reputable jewellers and auction houses.

Grading style

Similar strictness to GIA. Some studies suggest HRD and GIA grading align closely on colour, with minor variations on clarity.

At Jabour

We occasionally source HRD-certified stones for bespoke commissions.

Our promise

Every diamond Jabour & Co. sets — in any collection, at any price point — is accompanied by its full certificate. The certificate number is laser-inscribed on the girdle of the stone, allowing independent verification. We will always show you the certificate before purchase and explain every grade in plain language.

Ask Us About Our Diamonds