Shopping Cart (0)
My Diamonds (0)
My Jewelry (0)
My Diamond Pairs (0)
Last Visited Products

AGS, American Gem SocietyGIA, Gemological Institute of America


The Gemological Institute of America and the American Gemological Society were both founded by Robert Shipley in the 1930s. GIA’s Gem Trade Laboratory has been grading diamonds since 1939. These organizations are acknowledged as the most reputable diamond grading laboratories in the world. An official GIA or AGS document increases the value of a diamond. As of 2006 both of these labs are assigning cut grades for round brilliant diamonds. The AGS offers a grade for princess cuts as well.


The AGS began as a trade organization focused on ethical standards for retail jewelers and suppliers, and started developing a diamond grading standards manual in the 1960s. In 1996 the AGS Laboratories opened and introduced the first system of grading cut for round brilliants, based on proportions measurements, and officially introduced the term ‘ideal’ to grading. The AGS system is very strict. Only a small percentage of the world’s diamonds can earn the AGS top grade of 0 or “Ideal.” The GIA’s top grade of “Excellent” allows for a broader range of taste and overlaps several AGS grades. A diamond earning one of these grades will have passed all tests for depth, durability, polish and basic symmetry. It will also have visibly superior performance compared to average diamonds.


The AGS Ideal grade is considered very elite. The GIA Excellent grade has more latitude, but is still a good assurance of quality and durability. There are different interpretations of what ‘Ideal’ means. When you are considering a diamond advertised as ‘Ideal’ or ‘Excellent,’ you should find out if it was actually graded by the AGS or the GIA. If so it will be accompanied by an official document. It’s simple to call a diamond ‘ideal,’ but without proof or proportions or performance the term doesn’t guarantee anything.

For more specific questions ask our experts
Live chat by BoldChat

Continue shopping at

  • Follow Us
  • Sign up for our Newsletter:
    Whiteflash rating :
    4.80 Rating based on 4246 reviews. Read all testimonials
  • Contact Us
    Give us feedback Give us feedback
    Telephone 1-877-612-6770
    Outside USA 1-832-252-6770
    2150 Town Square Pl
    Sugar Land,
    TX 77479 USA
    Winner of the 2015 BBB Pinnacle Award
    Best Jeweler in Houston, Texas

Welcome to Whiteflash!

We cordially invite our Houston area clients to visit our beautiful boutique style showroom for a very special experience. Come see our A CUT ABOVE® diamonds and designer engagement rings in person and meet our friendly and knowledgeable staff of jewelry professionals.

Book your appointment now by visiting our Showroom Page where you can schedule your visit and learn more about the special venue we have created for our Houston area clients