A variety of bead-nucleated freshwater pearls (Oct 2011).
In-body bead-nucleation – details
In-body bead nucleated freshwater pearls differ significantly from flame type bead-nucleated China fw pearls, which became available during the past 8 years. Flame pearls are cultivated by inserting beads into pearl sacs that have been previously grafted in the mussel’s mantle, after harvesting a non-nucleated pearl that grew there. Flame pearls tend to have fluid shapes and smooth surface, while in-body pearls show better conformance to nucleus shape and a tendency for baroques to have a textured surface.
Long before flame type bead nucleated pearls appeared on the market, bead nuclei were used the same way in fw pearl cultivation as they are in ocean pearl cultivation such as akoya. The beads are implanted directly into the mussel’s body, among its organs. A small graft of active mantle tissue must accompany the bead. Given good conditions, it will grow into a pearl sac fitting snugly around the bead, and apply nacre layers more or less evenly to its entire surface. Separation of the graft from the bead results in a small non-nucleated pearl and an unchanged bead.
The technique was adapted for mussels by Haruo Sakai, celebrated fw cultivation pioneer and teacher to many, including our most informative Japan freshwater pearl supplier, Kazuhisa Yanase. It requires that nuclei be pre-drilled. A tapered tool is used, of a size that allows the tip to protrude a few mm from the shell bead. The active mantle tissue graft is then impaled on that tip, active side facing the bead, and the entire assembly inserted through an incision in the body covering to the “sweet spot” where the mussel will survive and a large round pearl will grow. Only the action of withdrawing the spike affixes the mantle graft securely enough to the bead nucleus. Akoya bead nucleation is done by first placing the undrilled nucleus using a tool with a cupped end that acts as a suction cup with water. The mantle tissue graft is then placed next to the bead using a pointed instrument. This technique frequently fails because of the greater muscular activity of the mussels, which causes separation of the graft from the bead. Yanase relates that Sakai, designated a Human National Treasure by the government and giver of gifts to the Imperial Family, let his patent lapse out of protest at the government’s allowing the Minamata tragedy (in which many people died of heavy metal poisoning from industrial pollution) to occur. Drilled nuclei are one clue that bead nucleated pearls have been cultivated in-body using this technique.
China freshwater pearls with pre-drilled shell nuclei 2011
Lake Biwa and Kasumi-ga-Ura areas in Japan produced in-body bead-nucleated fw pearls between the 1960′s and the 1980′s, and on a very small scale to the present day. Many operators made jobless by the 1980′s environmental disasters in Japan are believed to have taken their in-body nucleation skills to China. Why did the fruits of that technology transfer, probably initiated over 20 years ago, take so long to appear on the market? We believe it is due not merely to the techniques being closely guarded by those who acquired them, but also to the difference in skill levels required by in-body compared to mantle cultivation. Chinese akoya pearl cultivation began at least 10 years earlier, and also developed much more slowly than in-mantle freshwater pearl cultivation.
Fred Ward's rebuttal of GIA opinion that "no nucleated fw pearls are being made in China"2001
Bead-nucleated Chinese pearls that were probably in-body cultivated were purchased by Pacific Pearls in 2000, long before the first flame type bead-nucleated pearls appeared. One example, dyed black, inspired Fred Ward to bisect and photograph the pearls (see image below). His focus was mainly on the presence of a shell bead nucleus. GIA had just published a report, based on x-raying tens of thousands of pearls (from a single supplier) over several years, and concluding that no bead-nucleated pearls were made in China. Unfortunately, he made no shots of the surface, the texture of which was my clue that it is in-body nucleated. At this point in time, I had yet to encounter and to learn about flame-type in-mantle bead nucleation… which was never a significant product of Japan freshwater pearl cultivation.
We were frustrated because suppliers who occasionally offered in-body nucleated pearls called them yǒu hé zhū 有核珠 (having nucleus pearl) just like the flame type, and seemed not to have a term to describe the in-body pearls. Finally we learned that one supplier described his rough baroques as mǎo pí 毛 皮 (hairy skin). Incidentally, rosebud pearls with many little bumps on the surface are called máo zhū 毛珠 (hairy pearls). Another vendor calls in-body baroques mǎ pí 馬皮 (horse skin), yet another má pí 麻皮 (hemp-skin). A more vivid term is yáng méi 楊梅 a heavily textured fruit known as a waxberry or red bayberry. One vendor was quoted as naming them “Edison” pearls, perhaps a confusion with Franklin, and another announced they shall be known as “Ming” pearls, at any rate a Chinese word that most foreigners can remember.
The most relevant naming we can find for this type of pearl remains in-body bead nucleated.
We purchased similar pearls on several occasions between 1998 and late 2007, though quality tended to be poor. Imagine our surprise when we were suddenly offered not just beautiful varicolored baroques, but in a size rarely if ever attained in Japan! The price of course was also a world record, allowing us only to pick the biggest and best. The larger of 2 strands pictured measures 16.4 x 14.6mm in brilliant goldy colors, and was featured in David Federman’s “Gem Profile” column in April 2008 Modern Jeweler magazine. As the article points out, this strand reveals capabilities previously unknown, and makes it reasonable to expect similar, and even more desirable products to follow. David also reviewed flame-type pearls, giving them the name “fireballs”.
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