In-Body Bead-Nucleated (IBN) Freshwater Pearls

Ripple pearls = China freshwater IBN (In-body bead nucleated) pearls

Ripple pearls have texture typical of baroque and semi-baroque in-body nucleated freshwater pearl.

The most important accomplishment in China's pearl cultivation history reached a wider audience in this decade. At first the product had no widely known name, sharing "bead nucleated" with flame pearls, in spite of the very different operating skills required and the different look of the product. (See here for details.)

Baroque pearls  resulting from this cultivation method usually have surface texture causing them to be popularly known as ripple pearls. Now comprehension of this product is impeded by a surfeit of names, competing with each other in an industry obsessed with branding. "Proper" names, among them trademarks, say nothing about the product except who sells it. With pearls, proper names, eg Mallorca, have tended to imply imitations. The protagonists of names like "Ming", or "Edison" pearls are unlikely to succeed in making the whole world use their brand, downstream use of which merely implies a vendor knows no descriptive name, or perhaps is beholden to a certain supplier.

In-body (bead) nucleation is not a phrase that rolls off the tongue. At the turn of the century,  very few people were knowledgeable enough about pearl production to comprehend it.  But that is changing rapidly, with knowledge of pearls spreading even as we become aware of more products with different characteristics and requirements.

Baroque in-body nucleated ripple pearls tend to have a surface texture not seen in any bead-nuc pearls. It should come as no surprise that these pearls have many similarities to Japan Kasumi pearls, as those are all made by in-body nucleation. Many have deep colors and/or strong goldy highlights. Semi-baroque strands without major irregularities include extremely strong luster and colors.

Some people will invariably use a name associated with a certain "look".  The expression China Kasumi may serve to disambiguate, but is resented by our Japan Kasumi pearl suppliers, and not a proper use what is, after all, an abbreviated place name.  We prefer In-body bead nucleated  (IBN) as the most succinct and unequivocal naming for this product.

This "new" cultivation method has been done on a relatively small scale in China, probably since at least 1990. We were surprised by the beauty and size (13-16mm) of the pearls of this type that we have been able to acquire since late 2007, exceeding the norm for Lake Biwa and Kasumi-ga-Ura pearls produced at least since 1980. Both size and nacre thickness suggest that these pearls have been cultivated for decades,  rather than just for a few years.

Beginning in 2010, IBN pearls  became widely available in more common sizes in the range of 9 to 12mm. In less than 2 years all our China pearl suppliers offered them in quantity, and as of mid-2013 they seem more common than (mantle nucleated) flame pearls with round nuclei. Still there is not any uniform nomenclature in use to differentiate among products. The most time-honored naming for in-body (bead) nucleated (IBN) in our experience is "iketchoo", at truncation of the Japanese name for Hieryopsis schegeli mussels. The implication is that the mussels are pure-bred, in contrast to other freshwater pearls which are from hybrids viable in environments where ikechogai are not.  Regardless of the truth of this claim, I consider it disinformation to imply that the difference is due to species rather than pearling technique. To test our belief that they are in-body, we persuaded a dentist to make some x-rays. The films show two drill holes in every nucleus - the one from implantation and the one from assembly to strand. Please see Page 2 for an explanation of the use of pre-drilled nuclei in freshwater pearl cultivation.

China origin in-body nucleated pearls x-rayed to show double-drilled nuclei. It is probable that operators in China use the technique described to us by Kazuhisa Yanase. 

Semi-round to near-round in-body-nucleated pearls

Hitherto we observed that China produced rounder pearls without than with nucleus. This no longer holds; especially round pearls whose sizes exceed 10mm diameter are likely to be in-body bead nucleated. The roundest pearls of this type we offer mostly have dimples and other minor imperfections, but the quality/price ratio improves by leaps and bounds. These are clearly products of a maturing industry destined to dominate the market of large pearls as well.

Semiround and round in-body nucleated freshwater pearl with little or no texture

We see these pearls as an indication that Chinese production of freshwater pearls can indeed supply every type of fw pearl previously produced in Japan. Not only is the variety of pearl types now produced in China much wider, but the art of in-body cultivation could some day flourish there to an extent only dreamt of in Japan. That is to say, it could challenge every other cultivation of large high-quality pearls, all the while providing beautifully textured baroques like those shown here, a look unique to freshwater pearls.

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 around 2000.  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. According to Yanase, Sakai 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.  

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 an infinitesimal 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, and was probably abandoned.

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 is known for  naming them "Edison" pearls, and another announced they shall be known as "Ming" pearls, at any rate a Chinese word that most foreigners can remember.  It is important not to fall into the trap of using trademarks to describe pearl types (as I observed GIA representatives doing in 2023).  A success of some brilliance was attained with the "Kasumiga" brand some fifty years ago.  Only trademarks' owners may decide whch products can be given that name.  Non enforcement however encourages its use as a generic name or provenance, creating an advantge for them.

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".

1 comment

  • Elizabeth Kane

    The history you share of these pearls and the origin of their many names imparts a wealth of knowledge. A purchase in a jewelry store is simply a purchase but your site adds education that I personally find to be valuable. I want more than just the pearl-I want it’s story.

Leave a comment

Please note, comments must be approved before they are published