... for cubic zirconia, synthetic corundum, spinel, and glass production and the other is for synthetic jewelries such as necklace, rings, bangles ... not perfectly align it is not true H & A.Grading The HeartsQuick Guide1. 8 equal uniformed symmetrical hearts2. 8 distinct ... are split, measure length of heart then the length of the split.4. Calculate the % of the length split, if it is greater than ...