by mbn » Sep 11, 2001 I see many seller wanting to sell me high quality diamonds E/D color, VVS clarity. Some stores only sell stones with GIA certificate. Is it because seller gets more profit from selling higher quality stones because price is higher, and they get more commission? I know some sellers get anywhere from 1-5% commission fr. price of stone if they get stone from someone else if they don't have that stone.