57. IJS Istanbul Jewelry Show | 16-19 April 2025
58. IJS Istanbul Jewelry Show | 01-04 October 2025
  Venue | Istanbul Expo Center

What is a Diamond Certificate?

Estimated Reading Time: 4 min

The diamond is the processed form of the rock diamond formed under high heat and pressure over billions of years. The traces of each diamond in the formation and shaping process create its unique character. The quality and value of the diamond are revealed when the characteristic features are analyzed and documented in detail by experts.

What is a Diamond Certificate?

 A diamond certificate is a document that includes the technical characteristics of the diamond such as carat, size, color and clarity. All diamond-related
attributes, from crown height, table width, and to cone depth are listed in this certificate. There may be a disadvantage, especially for the seller, in the purchase and sale of products that do not have a diamond certificate.

How Should A Diamond Certificate Be?

The certificate date and report number are specified in the first part of the certificate, which called the 4C rule; diamond colour, carat (carat), clarity (brilliance), cut especially must be documented among other qualities. There are also organizations that determine the 4C features, which companies evaluate differently within the framework of their own standards, in accordance with international rules. For example, the criteria of leading international rating agencies such as GIA (American Gemology Institute), IGI and HRD Antwerp are valid all over the world.

Organizations that issue international diamond certificates generally carry out their work in laboratories with high technological facilities, serving in line with the special demands of diamond wholesalers or customers. In the laboratories of GIA, IGI, and HRD organizations; The grades of diamonds are determined by examining them with microscopes with 100x and 1000x degrees. In addition to measuring the color and clarity capacities of diamonds with special lenses and advanced microscopes, diamonds are examined by many different gemologists.

IDL (International Diamond Laboratory), headquartered in New York and providing international service, is one of the reliable certification companies of the sector. IDL prepares a large-size diamond certificate (stone book) for diamonds over 1 ct and a small-size diamond certificate for less than 1 ct. In addition to these, jewelery certificates and vacuumed diamond certificates are also within the scope of the certificate services carried out by IDL.

 While the certificates prepared by the brands have an average consistency rate of around 70%, this rate rises to 95% in international diamond certificates. The reason for this is the difference in the development of laboratory facilities. Diamond stone products sold with international certification may be 20% to 30% more expensive than their counterparts. International diamond certification is divided into two categories:

  • Stone Certificate (Diamond Certificate): These are the certificates in which the gemstone information is transferred to the document in the most detailed form by examining the diamond before it is processed into jewelry. Even if the gem of the stone is changed, this certificate does not lose its validity.
  • Jewelry Certificate: It is the certification of the stone and the jewel as a whole, not separately. In such certificates created after manufacturing, the jewel does not contain all the information about the diamond, as it covers some points of the stone.

How to Get a Diamond Certificate?

Diamond certificates, which are provided for customers by brands or diamond wholesalers, can be prepared by the examinations made in the private laboratories of the companies, or they can be requested from international organizations.

In order to get a diamond certificate from the prestigious certification company GIA, you must remove the stone from the jewelery it assembled in and pack it, then fill in the container label. For security reasons, you should not include the company name or logo when filling out the label. You must contact the GIA to request the Patriotic Consent and Compliance Act, the Kimberley Process Certificate and a signed Customer Agreement Form.

Since the gemology laboratories of the company are located in New York and California, if you do not have the opportunity to deliver the diamond personally, it is recommended to send it by airmail in a certified and secure package with signature requirement. In addition to the fee determined for the weight of the stone, a fee is also made for the qualification report, laser writing, file recording, analysis and quality assurance. The preparation and shipping time of the report differs according to the diamond's carat, color and report content.

What Does a Diamond Certificate Do?

The diamond certificate, above all, proves the quality and originality of the diamond. The information in the certificate should be consulted to determine the value of the diamond; considering that many elements of the diamond can make a difference in price. The diamond certificate obtained from reliable institutions has great importance, in order to prevent errors that may occur while determining the weight, shape, color and clarity of uncertified products.

 Eliminating the trust problem between the seller and the buyer is one of the most important issues in the trade of valuable stones such as diamonds. Diamonds, which are generally considered to be resold in the future by the purchaser, are one of the most depreciated products in the second-hand market. In such cases; it is very important that the product is certified, to minimize possible losses. In addition, a product certificate will help insurance companies to prove the value of the diamond if you encounter cases of theft.

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