A Guide to Diamond Certification

Gemological Institute of America

The Gemological Institute of America (GIA): Established in 1931, the GIA is a public-benefit, non-profit institute renowned for its gemmological research.

The GIA’s discoveries continue to deepen an understanding of gemstones and the world. The GIA protects consumers through analysis, education, and gem grading and sets global quality standards. The GIA independently verifies the origins of many of Graff’s diamonds and gemstones. 

The GIA developed a standardised carat weight grading system to ensure consistency and accuracy in diamond grading. The system ranges from 0.01 to 10 carats, with each category representing a specific range of weights. 

As you embark upon your diamond journey, remember that obtaining diamond certification is vital in ensuring both quality and authenticity. A certified diamond provides transparency, reassurance, and peace of mind.

At Graff, every diamond is traceable to its source, having been procured from only known, vetted and audited sources and responsibly mined in accordance with the Kimberley Process – ensuring each stone's ethical, conflict-free provenance is diligently maintained. Throughout the history of the House, which spans more than 65 years, long-lasting relationships with key mines in Africa – renowned for mining significant gem-quality diamonds – have been established. In addition, Graff has been a sight holder to the Diamond Trading Company for more than two decades. 

Dedicated stone experts at Graff’s global headquarters in London partner with a limited number of highly reputable suppliers and travel the globe attending diamond tenders in pursuit of the finest stones. Many of Graff’s diamonds and gemstones are inscribed with the Graff logo, using laser-engraving technology, which is invisible to the naked eye. This seal of quality is visible through a loupe (a small magnifying glass used by jewellers to measure and examine stones) and provides Graff’s clients with the assurance that these stones have passed a rigorous selection process while ensuring an unrivalled level of authenticity.