Frankly most pearl resellers on the Internet will never describe their products (regardless of actual quality) as anything other than "Excellent AAA" or some similar description.  We have a different philosophy; Always Tell the Truth. The highest quality (at the highest price) isn't always the right choice for everyone or for every purpose.

One reason for the confusion and inconsistancy in pearl quality descriptions is that there is no universally accepted standardized grading system within the cultured pearl industry.  Therefore we will describe our pearl's quality in terms which are modeled after the Tahitian Pearl Grading System used for Tahitian "Black" pearls.

A:  Very good luster, one visible flaw or a few slight imperfections at the most, distributed over less than 10% of the surface.
B:  Good or medium luster, some slight flaws visible to the naked eye and distributed over 30% of the surface at the most.
C:  Medium luster.  Several light flaws distributed over 60% of the surface at the most.
D:  Either a large amount of slight flaws distributed over 60% of the surface, or several slight and deep flaws distributed over 60% of the surface at the most, regardless of the luster.