Diamond Certificate

‏The GDI Diamond Certificate provides a reliable and accurate documentation of a diamond’s identity and grade based on the internationally recognized diamond grading system. Using state-of-the-art equipment, each diamond is analyzed by several gemologists in order to provide the most accurate description of the diamond’s quality and characteristics. The carat, color, clarity and cut – commonly known as the 4 C’s of each diamond are clearly stated on each diamond certificate. Additional grading characteristics such as the finish, girdle, culet and fluorescence are also detailed on the certificate. A diagram of the diamond displaying any inclusions is also included on the certificate.

Jewelry Certificate

The GDI Jewelry certificate is used to document jewelry pieces and identify the characteristics of the precious stones featured in each piece. Each GDI Jewelry certificate features a description of the jewelry piece followed by a statement of the characteristics and grading of the precious stones found in the piece. A statement listing the quantity of gemstones featured in the piece as well as a grading report of the gemstone’s weight, shape, color, clarity, cut, proportions and measurements are featured in the GDI Jewelry Certificate. In addition, the identification, weight and content of any precious metals found in the piece are described on the certificate. As a further way to identify the jewelry piece, the GDI Jewelry certificate features an enlarged color photograph of the item. Upon request, the GDI Laboratory can easily convert an GDI Jewelry Certificate into an appraisal certificate.


CertiCard, a credit card sized certificate is the ultimate diamond ID. It includes a majority of the information that appears on a full GDI Diamond Certificate, as well as a digital image of the diamond face.

‏‏Colored Gemstone Certificate

GDI have equipped ourselves with the most technologically advanced equipment available for the use in the identification and authentication of colored gemstones. GDI Laboratories are equipped with immersion cells, micrometers, spectroscopes, polariscopes, refractometers, specific gravity liquids, binocular microscopes and spectrophotometers. Each GDI Colored Gemstone Certificate clearly states whether the stone is natural or synthetic. The certificate identifies the variety of the gemstone, its shape, carat weight, cut, color quality, measurements, transparency factor and major optical (?) characteristics. If the stone has undergone any treatment, this information will be listed on the certificate as well. Upon request, the origin of the gemstone may be determined.

Hearts and Arrows Diamond Certificate

Round brilliant cut diamonds with ideal proportions, polish and symmetry become “Hearts and Arrows” diamonds These stones display a visual pattern of 8 hearts looking down through the pavilion and 8 arrows when viewing the stone in the table up position. A special viewer (Hearts and Arrows Gemscope) is used to show this effect. The AIG Hearts and Arrows Diamond Report can include either the actual pictures confirming the hearts and arrows of the stone, or the hearts and arrows visual illustration.

Mini Certificates

Mini Certificates display all of the details of a regular certificate but come written on a more compact document.

Security Sealed

GDI offers an advanced sealing system for loose diamonds in which a diamond is sealed in a secure and tamper-proof casing. The GDI Certi-Card Sealing System is the best way to safeguard your diamond against being substituted, chipped, fractured, or otherwise damaged before you have it set into jewellery or while it is not in your possession. Once GDI has issued a Diamond Certificate, on your request the diamond is sealed in the Certi-Card casing with its individual GDI Diamond Certificate number and identifying characteristics clearly visible inside the seal. The seal has a number of security features including electrostatic security bars, pressure-sensitive transparent adhesive and Cryptoprint text which only becomes visible after opening the seal. It is therefore impossible to tamper with the seal.