About diamond certificates

Diamonds can have certificates that state their quality as the quality or grade of a diamond will determine it's value

A diamond certificate is issued following an unbiased and professional examination to authenticate a diamond's attributes.

The carat weight, colour and clarity are all validated, together with the diamond's exact measurements and there may be some reference to the symmetry or polish quality of the stone.

Cut grades are also included for Round Brilliant cuts. Certificates are essential in determining or testifying a diamond's value.

It is generally accepted by diamond industry professionals that the Gemological Institute of America (GIA) sets the standard when it comes to diamond grading and are therefore diamonds with a GIA certificate are a little more expensive than diamonds with certificates from other grading bodies.

At Victoria james we only sell independantly certificated diamonds.

Diamonds sold by Victoria James jewellers have been graded by GIA, HRD, IGI, or IGR, Anchorcert, AGI.

GIA (Gemological Institute of America)

The Gemological institute of America was established by Robert M Shipley in 1931. It has been dedicated to ensuring the public trust in gems and jewellery by upholding the highest standards of integrity, Academics, science and professionalism. Many of the worlds finest diamonds have been graded by the GIA such as the Hope Diamond and the DeBeers Millennium Star. It is also the creator of the 4 C's of diamond value now adopted internationally. 

Logo of Gemological Institute of America 

IGI (International Gemological Institute)

IGI is one of the world's largest independent institutes handling a large majority of the worlds certified diamonds. It is renowned for its quality services, extensive experience and know how. It was founded in 1975 and along with its sister laboratories, is one of the leading gemological institutes worldwide. IGI issues more than reports on certified diamonds each year. 

 Logo of International Gemological Institute

HRD (Hoge Raad voor Diamant)

Established in 1973 as the 'Hoge Raad voor Diamant' or 'Diamond High Council,' the organisation has become the major employer of the Antwerp diamond sector. The HRD acts as spokesperson of the sector towards authorities and third parties and offers a wide range of services including the issue of certified diamond reports for loose polished diamonds from the HRD Certificates Department. It issues one of the world's most respected diamond certificates and jewellery reports and is the first diamond lab in the world that is NBN EN ISO/IEC 17025-certified.

Logo of Hoge Raad voor Diamant


AnchorCert Gem Lab provides diamond, gemstone and pearl reports by highly qualified Gemmologists and Diamond Graders from its Centre of Excellence in  Assay Office Birmingham. Integrity and an unbiased independent opinion every time are guaranteed. AnchorCert offers a wide range of services including verbal and written assessments of loose and mounted stones. 

Logo of Anchorcert

IGR (International Gemological Reports)

IGR laboratory is a Hatton garden (London) based diamond grading laboratory. They provide a range of services and diamond grading reports and their UK location provides a convenient location for UK jewellers ensuring a fast turnaround on diamond certificates. The informative IGR website is nicely presented, with a great insight into the style of their reports and the range of services provided.  

Logo of International Gemoloical Reports


AGI (Antwerpse Gemologische Instelling)

AGI is an abbreviation for Antwerpse Gemologische Instelling. Their byline is 'understanding diamonds.' They are located in Antwerp and Manchester, making UK diamond certification convenient, with full size diamond grading reports available for diamond submitted. Their service is speedy and reliable. They have been operating in the UK since 2000, and now have over 13,000 clients Worldwide. Like GIA, their website offers a validation service enabling owners to enter the report number for details of their diamond. 

Logo of Antwerpse Gemologische Instelling