A diamond-grading certificate or Gemological laboratory report is a document given by an independent and professional laboratory. The diamond is documented for its quality, measurements and characteristics, not its value. A paper or report stating value is an appraisal and should be separate from the grading report or certificate. Diamonds are unique and their characteristics will be shown or listed on a quality certificate or report. A high quality certificate will document all the diamond's recognizable and individual characteristics. Each certificate will include the diamond's color, clarity, carat and cut information (see the 4 C's of quality). The grading report also includes a hand-drawn map called a plotting of the diamond's inclusions, surface blemishes, shape and facets. Since no two diamonds are exactly alike, you can always check that the certificate matches the diamond.
There are several fine quality gemological laboratories providing these professional services. The most respected and renowned will be GIA—standing for the Gemological Institute of America—located in Los Angeles CA and New York City. They perfected the world-wide grading system in use today. EGL—or the European Gemological Laboratory—certificates are very popular and offer a similar service at a slightly lower cost and faster turnaround making them very popular with large diamond manufactures and volume diamond brokers. AGS American Gemological Services, IGI International Gemological Institute, and GQI Gemological Quality Institute are also quality laboratories offering a variety of professional services.
It is crucial to remember you are not just buying the certificate! You should not focus solely in the report of the stone—many stones look better on paper than they will in comparison to another stone with a less impressive looking paper. Beauty is in the eye of the beholder and your choice of cut, color, clarity, carat, and shape is individual and the most important factor of all. At Grissom’s we pride ourselves in offering an outstanding level of service, quality, value and selection to ensure the diamond you buy will make dreams come true.