MikimotoMikimoto

 

Mikimoto Grading SystemMikimoto Grading System

Pearls are like fingerprints; each is unique. In 1974, Mikimoto established an industry standard with the first grading system in the U.S. for Akoya cultured pearls. Based on consumer demand, Mikimoto eventually adapted the system to grade South Sea cultured pearls.

Setting the Standard

While imitation systems exist, Mikimoto literally sets the standard for grading the quality of cultured pearls.
The Mikimoto pearl grading scale illustrates the system, with AAA representing the very highest quality.

View Mikimoto Pearl Grading Scale

Although no single factor can solely represent the worth of a pearl, luster and surface perfection are most important. Mikimoto graders spend years becoming experts in assessing these gems of the sea.

The Pearl Pyramid

The 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.

Close

QualityLusterSurface
AAAExceptional, Mirror-Like ReflectionBlemish-Free Surface*
AASuperb, Clear ReflectionVery Slightly Blemished
A+Very Good, Clear ReflectionVery Slightly Blemished
AGood, Clear ReflectionVery Slightly Blemished
A1Good, Clear ReflectionSlightly Blemished

* Tiny marks are part of the pearl's natural texture.

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