Can you imagine the confusion if we were to try to grade per Tavernier? I am sure our French customers would appreciate it, but many others may getting confused with grain and carat approximations!
I do think it is important to note, however, even on the top quality freshwater pearls bleaching is still going to be part of the process. I firmly believe it brings out the beauty of pearls, and without any bleaching the ratios would just be too low from a merchant's standpoint.