While luster, pearl quality, surface perfection, color, shape and size are standard factors for pearl grading, the MIKIMOTO pearl grading scale is the only qualified system which accurately and consistently defines these factors by four individual grade categories.

No one factor can solely represent the worth of a pearl, but luster and surface perfection are key factors in grading a pearl. There are four MIKIMOTO grades, AAA being the highest quality: A, A+, AA and AAA. There are also four sub-grades: A1, A+1, AA1 and AAA1. The "1" represents a slightly more blemished surface.

This Pearl Pyramid represents the quantity and quality of all cultured pearls harvested in Japan. Only the best cultured pearls are deemed worthy to carry the MIKIMOTO name.