Tahitian Pearl Grading
Grading systems
There are two grading systems used to categorize pearls. The first, and the one we use at Kamoka, is the Tahitian system which uses A, B, C and D to classify the quality of a Tahitian pearl. The second system is the GIA (Gemological Institute of America) that uses A, AA, AAA and AAAA as classification -- this system is used in a variety of pearl types including Tahitians. Both systems are imperfect and very subjective, meaning that a pearl that might be given one classification by one person, might be given another by someone else.
How we grade at Kamoka
At Kamoka we use the Tahitian system and grade according to the more measurable criteria of size, shape, color, luster and skin quality, but sometimes a pearl might get edged up higher simply because of its special glow, or pushed down a category because it just isn't pretty enough.
Color is a wildcard that can add or subtract value to a pearl no matter what its grade. For example, a rare flashy cherry color pearl will be sold for far more than a silvery tone with no overtones even if they are technically the same grade of pearl.
We have seen hundreds of thousands of pearls over our 30 years in the industry, and feel confident about the category in which each belongs.
The Tahitian Grading System
Under the Tahitian system, quality is broken down into A, B, C and D categories.
Grade |
A |
B |
C |
D |
Description |
Top grade, the top 1-5% of the harvest. For the finest pieces in settings that don’t hide the pearl. |
Very beautiful, fine pearls with few flaws, the top 10% of a harvest. |
Pretty and very sellable, commercial grade representing the bulk of a harvest. |
These are flawed pearls or pearls without good luster. Great for leather or lower end jewelry. |
Surface |
Imperfections on 5% or less of the surface. |
Flawless on at least 80% of the surface with maximum 2 deep imperfections that can be covered by a jewelry mounting. |
At least 40% of the surface must be free of flaws is one clean face that can look beautiful when mounted in jewelry. |
Flaws over most of the surface or dull pearls. Some can be very colorful & lustrous, just pitted. Others dull with few flaws. |
Luster |
Very high |
High to very high. |
Medium to very high. |
Poor to high. |
GIA System Equivalent |
AAAA |
AAA |
AA |
A |