Certificated Stones

What is a certificated stone? A certificated stone has been weighed and graded by a laboratory, which has issued a certificate, or Diamond Grading Report, that presents their evaluation of the stone, including identifying characteristics. The purpose is to obtain a thorough and accurate description of the diamond, using accepted grading scales and measures, done by an independent expert with no financial interest in the outcome of the grading process.

What is the difference between "certified" and "certificated" stones? The terms tend to be used interchangeably, but virtually every time someone tells you a diamond is certified, they mean certificated, as defined above. The term "certified" implies some guarantee, some recourse should you determine the evaluation to be inaccurate. Diamond certificates issued by the recognized laboratories typically state, "This report is not a guarantee," thus they are not "certifying" the stones.

Are all certificates equally valid and valuable? Some laboratories have a reputation for higher accuracy in the grading process, and therefore are able to charge more for their certificates.

Premium certificates include the following laboratories:

• GIA - Geological Institute of America
  
• HRD - High Council of Belgium (European)
  
• AGS - American Gem Society
  
• EGL, Los Angeles Branch - European Gemological Laboratory

Second Tier of well-known laboratories:

• IGI - International Gem Institute
• EGL, New York or Belgian Branch

Do not equate a certificate from an established laboratory with a "certificate" issued by the person or business selling you the diamond. The latter would be better termed an "appraisal" -- and not an independent one at that. It's not that an in-store grading report has no merit -- simply that it doesn't make the diamond "certificated" by the standards of jewelry profession.

How will I know if the diamond delivered to me is actually the stone described in the certificate? If you purchase the diamond from a trustworthy and qualified jeweler, they should already have made the confirmation that the stone is as described in the certificate. But don't be afraid to ask. And if bought from an unknown source, take it to a qualified jeweler for the identification you need (usually for a modest fee).

Is it important to buy only certificated stones? The majority of diamonds sold in jewelry are not certificated. And that includes many beautiful diamonds that are accurately graded by jewelers instead of by laboratories. Rather than limit yourself to certificated stones, you may choose to buy only from a trusted jeweler, and/or always obtain a second opinion as to the size and grade of your purchase. See our section on How to protect yourself against diamond overgrading.