Stone Grade

Regarding natural stones, unfortunately there is no international standard. But in general stones are graded from A up to AAAAA.

A: Minimum grade

AA: Normal grade

AAA: Good grade

AAAA: Very good grade

AAAAA: The best grade

*「+」is used between grades.



Grade is determined by transparency, color, glitter, clack, inclusion etc but it depends on stone type also.

Meantime special inclusion or clack make the stone unique and only one piece in the world. We recommend that it is better to follow your feeling when you choose.