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Pearl Identification and Quality Analysis certification_en

2023年01月20日

Pearl identification in Japan dates back to 1974, when the former director and current Honorary Advisor, Hiroshi Komatsu published an article entitled “Identification of Black Pearls” in the official GIA journal of the United States.

Since then, Pearl Science Laboratory has been developing new identification methods and equipment.

Therefore, we are widely recognized as the highest authority on pearl identification in Japan and abroad.

Certificates of authenticity and identification will only be issued upon request from pearl dealers.

PSL Pearl Grading System

Pearl Mark

What is Pearl Mark?

The pearl mark will be given to pearls that have passed seven quality standards.

The pearl mark system was introduced in 2000 when the PSL pearl grading system was announced. The purpose of the pearl mark system is to set quality standards and to inspect and certify that pearls have sufficient value as a product.

This is the fundamental concept of pearls and forms the basis of pearl grading. The quality standards are based on (1) maintaining the durability of the nacreous layer and (2) preventing deviation from the definition of pearls, and the following seven items must be met. (Source: PSL Pearl Grading System 2008, revised edition)

Cultured half-sphere pearls and cultured three-quarter pearls are not applicable.
Not applicable to pearls with an exposed prismatic layer or organic layer.
Not applicable to pearls that are damaged, cracked, or have exposed cross-sections due to cutting.
Pearls with a thin nacreous layer, of which the pattern of an internal nucleus is visible, are not applicable.
Pearls with a broken nucleus inside are not applicable.
Pearls with processing flaws (cracks, peeling, fissures, spots) will not be accepted.
Pearls with excessive coloring that may cause problems when worn are not applicable.

Certificate of High-quality Pearl Identification & Grading

The Certificate of High-quality Pearl Identification & Grading is for pearls that have passed a quality check, the pearl mark inspection.

Best Quality Mark

The Certificate of Pearl Identification & Grading with Best Quality Mark will be issued for pearls that are in the highest category in the evaluation stage for all five quality components. There are special designations for each mother shell.

Best TERI Mark

TERI, the brightness and the color of light interference on a pearl, is the essence of pearls. For pearls with the best TERI, the Certificate of Pearl Identification & Grading with Best TERI Mark will be issued.

TERI Mark

TERI is an important element of pearls. For pearls with excellent TERI, the Certificate of Pearl Identification & Grading with TERI Mark will be issued to prove its brilliance.

About Certificate of Pearl Identification & Grading

Certificate of Pearl Identification & Grading SP type (former Type P)

This is the exclusive certificate for the Aurora TEN-NYO. A TERI Value Analysis is performed and an aurora image is attached.
The Aurora TEN-NYO is the one with the highest level of TERI among the Aurora HANADAMA.

Certificate of Pearl Identification & Grading SS Type (former Type S)

This certificate is issued for the highest quality series of each mother shell. This certificate is used for the Aurora HANADAMA.
Statements such as natural color can be added.
The nacre thickness is measured by X-ray.

What is Aurora HANADAMA?