Gemological Grading Services is an independent diamond, colored gem, jewelry appraisal and certification service for both individual and wholesale diamond enthusiasts all over the world. With locations in Los Angeles, New York, India, Israel, Belgium and Hong Kong, you can rest assured that your GGS appraisal is conducted based on only the most meticulous and accepted international standards. When your appraisal is done by GGS, your diamonds and gems will be measured, identified, graded, and evaluated down to the most finite details so that you have a full assessment of the items in your possession. Please read on to learn more about our Appraisal and Certification processes.