10 Things You Need to Know About Round Diamond Certification

1. The two most respected and trusted gemological laboratories in the world for diamond certification are the GIA (Gemological Institute of America) Gem Trade Laboratory and the AGS (American Gem Society) Laboratory. The AGS was established by the founders of the GIA.

2. The GIA is the most well-known lab having developed the color and clarity grading system used today throughout the world. The AGS lab is world renowned for diamond cut grading.

3. The AGS Laboratory pioneered the science of diamond cut quality analysis, and is the foremost authority in this critical area of diamond grading.

4. The AGS certificate is the document most trusted by those looking for the very best in diamond cut craftsmanship and light performance, such a super ideal diamonds.

5. The GIA report provides a cut grade for ONLY round diamonds, while the AGS provides cut grades for princess cut diamonds and several other diamond shapes.

6. Customers looking for certified IDEAL diamonds require AGS certificates as the GIA grading system does not use the term “Ideal”.

7. The highest diamond cut grade in the GIA system is “Excellent” and is a broader category than AGS Ideal. The AGS diamond cut grading system is much stricter than that of the GIA.

8. The AGS grading system uses a numerical rating from 0-10. Zero indicates zero deductions and is equivalent to IDEAL. An AGS Ideal diamond is thus known as AGS 0 (AGS Zero). Sometimes they are referred to as “Triple 0” indicating Ideal light performance, polish and symmetry.

9. The modern AGS grading system is light performance based and involves a system called ASET (Angular Spectrum Evaluation Tool) The desktop and handheld versions of the ASET tool provide quick and easy visual analysis of a diamond’s light performance.

10. The ultimate diamond pedigree is the AGS Platinum certificate which features the diamond color, clarity, weight, measurements, proportions, cut craftsmanship, and light performance. A computer generated ASET light map is also part of the AGS Platinum certificate.