The Pearl Science Laboratory (PSL) of Japan Certification

The Pearl Science Laboratory (PSL) of Japan is located in Tokyo, Japan. It is the only recognized certifier of Hanadama quality Japanese Akoya pearls in the world. Hanadama is a Japanese term that was coined by the founder of the cultured Akoya pearling industry, Kokichi Mikimoto, which means spherical flower. Hanadama pearls comprise less than 0.01% of the Akoya pearls harvested. The Hanadama grade is still used to this day to designate the best quality Akoya saltwater pearls that can be found.

In order to have a hank of pearls certified as being Hanadama they are submitted to the Pearl Science Laboratory of Japan to under go a series of tests on random pearls from the strand; such as soft x-rays, light spectro photometric reflectance, magnification and inner inspection by optical fiber. This allows the PSL to exactly measure nacre thickness, luster, surface imperfections, (etc.). At the end of this analysis if a hank has met the criteria for being of Hanadama grade a numbered certificate will be assigned to the hank of pearls by the PSL deeming it to be Hanadama grade.

The grading is not subjective, and must meet the following criteria:

Nacre depth must not show to be less than 0.4mm (0.8mm when two sides are added)
Teri-value (luster) analysis must be very strong
Surface imperfection (inclusion) grade must read very slight

Although the certificate allows for thicker nacre grading than the minimum required of 0.4mm, it is important to remember that this test is performed on a random selection of pearls. Each pearl will vary on every Hanadama strand and will have pearls with nacre depths ranging from 0.4mm to 1.0mm or higher. It is impossible to guarantee consistent nacre depth within a single strand. Every pearl is unique - and that is the beauty of how Mother Nature creates pearls.

The PSL certificate does not allow for grading of no imperfections. This is because all pearls will have some degree of imperfection. Pearls are an organic gem, and though imperfections may be indistinguishable to the eye, they will still exist. For that reason the Pearl Science Laboratory of Japan does not allow for a 'perfectly flawless' grading.

Mapping the PSL Hanadama Grade to the GIA Grade

Although Hanadama is an industry term, it is not a designation in the GIA A-AAA grading system. Technically speaking, a Hanadama rating is best described as the top portion of the AAA GIA category. Please keep in mind, there is nothing beyond a AAA rating according to the GIA - so if you encounter AAA+ or AAAA it is hyperbole. At the same time, different retailers have different views as to what qualifies as AAA, making the classification somewhat inconsistent, often confusing consumers.

To assist our customers and preserve our AAA standard, we offer both our AAA and Hanadama necklaces with PSL certificates in our larger Japanese Akoya necklaces. As our larger AAA Japanese Akoya pearls were already at this quality level, we made this change to provide more assurance into the quality of necklace being purchased. Our AAA grade meets all Hanadama certification requirements, but our Hanadama grade exceeds these requirements making it to us a true Hanadama piece.