The highest quality range of Japanese Akoya Cultured Pearl, almost no blemishes, that means at least 95% of the surface will be free from blemishes. Very thick nacre, and the surface will have a very strong luster. In multi-pearl pieces such as strands, bracelets, etc., a few pearls may not absolutely meet the indicated level because of emphasizing "matching".

Hanadama: Pearl Science Laboratory's own grade.
They define "Hanadama" in terms of conditions as below.

*Apply to over 6mm pearls
*Nacre thickness should be more than 0.4mm
*Tolerance level in shape is Round to Semi-Round.
*Imperfections(surface) is inspected based on Pearl Science Laboratorys' standard.
*The most important thing is "Luster". Shine and overtones are inspected based on Pearl Science Laboratorys' standard.
*Artificial blemishes which influence durability should be rejected.

Thick nacre, and the surface will have strong luster. At least 75% of the surface will be free from blemishes. In multi-pearl pieces such as strands, bracelets, etc., a few pearls may not absolutely meet the indicated level because of emphasizing "matching".

Pearl quality must be appraised by humans, making appraisal a necessarily subjective process, and there is not yet a common international standard ranking system for pearl quality. While understandable, this unfortunately complicates things for buyers such as yourself: for example, our company’s "AA" pearls may significantly differ in quality from the "AA" pearls being sold by another company. It is simply impossible to judge pearl quality by alphanumeric ranking alone.

For this reason, to be absolutely sure, we recommend that you purchase only from suppliers who abide by the strictest standards in pearl selection, as we do at Yokota Pearls.

Only a low temperature of sea in winter can make pearl luster very fine. In this meaning, Japan is the best place to cultivate high quality Akoya Pearls. Asian nations other than Japan do not have best suited temperature to make Akoya Pearl shine.

There are three main types of Akoya pearls. Akoya pearls may be:

1. Raised in Japanese Akoya oysters here in Japan.

2. Raised in half-Chinese, half-Japanese oysters here in Japan.

3. Raised in Chinese or other Asian oysters, in China or other Asian Countries.

Japan is the birthplace of the cultured pearl, and, with over 120 years of history, it’s safe to say that we have the advantage. In recent years, the type 2. and type 3. pearls on the market have become much more attractive than before, but their quality nonetheless still pales in comparison to type 1. Akoya pearls. At Yokota Pearls, we deal in only type 1. pearls, and only the finest from among those. They do cost considerably more than pearl types 2. and 3., but we promise that the difference in quality more than compensates for the difference in price.