Question for Dave Atlas: Did AGA Cut Grade Charts Change?

[Thegroom]

When I was buying a round brilliant diamond last september, I seem to remember that my stone had a 1B rating for crown angle (34.0 degrees) and a 1A rating for crown height (14.4%). If I remember correctly, the lower criteria at that time for 1A crown angle used to be 34.3 degrees and now it''s 34.0 degrees. The lower criteria for crown height for 1A was 14.4%, now it''s 14.3%. None of this effects how much I love my brides diamond, but I was just curious if you changed these and why? Or maybe I just am remembering incorrectly... Thanks,

Mick

 

[Magnum]

You're right, there have been changes, crown angle being one of them. Here's a thread that Dave Atlas started to explain the changes:

AGA revised Cut Class grades now live

 

[skyline]

Hi,
Just out of curosity's sake, what were the old AGA parameters?

Thanks.