GEM  / Exceptional(9-10) (C14_5_6)
AAA  / EX. FINE(8-9) (C14_4_4)
AA  / FINE(6-8) (C14_3_4)
A  / GOOD(4-6) (C14_3_2)
B  / Commercial(3-4) (C13_6_2)
C  / Lower Commercial(1-3) (C13_7_1)