Just wondering....about "natural" keshis

Caitlin

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Please pardon my imagination

I am thinking about the keshi-called-naturals. I am so puzzled about why/how keshi form. Something must have roughed the mollusks' mantles up enough to stimulate tiny pearl sacks to form.

Couldn't pearl growers simply poke the mantles of mollusks just enough to carry a few cells of epithelial tissue inside the mantle? These would often produce pearl sacks and thus deliberate keshi could be formed. Maybe with the correct poker-thingy the shapes of the pearls could be made rounder?

So the keshi-called naturals could be formed by a good poke in the mantle, then left to form pearl sacks which would then grow a "Natural Pearl"- in the mantle where such things usually grow. It is probably far less traumatic than a wound to the gonads.

Why wouldn't this work?
 
Couldn't pearl growers simply poke the mantles of mollusks just enough to carry a few cells of epithelial tissue inside the mantle? These would often produce pearl sacks and thus deliberate keshi could be formed. Maybe with the correct poker-thingy the shapes of the pearls could be made rounder?
It would seem this is exactly what is taking place, especially in places like Indonesia, resulting in the flood of keshis (pre-screened for 'naturalness' in lab X-Rays) being received by the pearl labs. Thus the just-completed, unprecedented urgent conference among the labs, and the moratorium by at least one regarding continuing certification of loose Pinctada pearls.
 
Of course it is a cultural event. That is the problem with calling them naturals instead of keshi.
There seem to be 2 problems with this.
They have gotten so good at making deliberate round keshi
-and the auction houses have a tradition of calling keshi naturals-that they think it is ok to call deliberately controlled keshi, naturals.

It seems to me that the auction houses are the actual cause of this loophole.
 
It seems to me that the auction houses are the actual cause of this loophole.
That the auction houses would maximize the value of keshi via undue comparison with natural is shameful, but I don't see them going so far as to risk devaluating their lucrative natural pearl lots.

The more insidious crime is the use of natural pearl beads (specifically pinna) as exposed by GemLab, given the undeniable intent to deceive. Keshis are a bit more innocent in origin, but the root of apparently massive deception nonetheless.

Let's just hope that the collective research of the pearl labs resulting from their recent Persian Gulf conference can come up with definitive tests for keshi vs. natural soon, thus allowing pearl lovers to benefit from the advances in non-bead-nucleated saltwaters, while preserving the traditions and integrity of the natural market.
 
I am so with you on this. I await the answer with impatience.

Using pinna pearls to nucleate is a great way to get solid nacre pearls and it recycles the pinna pearls in a really useful way. It just should be disclosed. Getting those perfect round keshi is nice too, anther way to get solid nacre, in nice round shapes, but it should be disclosed too.

It destroys the rarity of natural pearls to pass cultured pearls off as natural. Natural pearls are wild-grown. No person's hand can be on them, helping them in any way, from causing a pearl to form, to tending it in any way.

I'd like to see a sign that the auction houses are listening up. After all a bunch of people already have "natural" keshi pearl necklaces. Now the auction houses have to correct that poor practice and anger a bunch of customers who don't have natural, pearls afterall. I wonder how long it will take for them figure out a way to explain themselves.

In fact, I think auction houses created the loophole/market for natural keshi. If keshi are called natural, then certainly beautiful, fat, round keshi should be natural too. The pearl labs did not interfere with auction houses for years when they called keshi natural pearls- and now someone clever has just expanded the loophole by producing really round keshi.

This is a mess created by greed.
 
It destroys the rarity of natural pearls to pass cultured pearls off as natural ....

Thank you.

After xrays, microscopy, weighing etc, many naturals never get certified. Most labs have little or no baseline data to compare each and every species. It's expensive, strict and time consuming.

Even provenance from licensing, leases, photography etc., does little to dispell the skepticism.

"Human intervention by any means" is a term some will sidestep when it comes to keshi pearls. Harvesting and relaying spat is mariculture. In the rare event a mollusk forms a pearl naturally during juvenile rearing, it's still within a cultured environment, hence it's value is overshadowed by default.

The natural might sometimes be older in age from pre-graft development, presenting with more layers or expanded seasonal growth patterns.

So you are right Caitlin, it destroys the rarity of natural pearls to pass cultured pearls off as natural, because it causes naturals to get passed off as keshis.
 
Just to inform you of some of our "old" research in the field of Pearl Production (circa 1995): we tried many methods of pearl production in many different species of native bivalves (Rainbow & Black Lips, Pen shells and Scallops) including: using "needles" to displace the mantle within itself, electric shocks on the mantle, chemical & neurotoxic damage on the mantle, biological threats (thank God George Bush Jr. never heard of this...) on the mantle such as: polychaete worms, cnidarian stings, bee stings. Heck! We even tried sand! In all instances: ZERO PEARLS.
It ain't easy to grow cultured pearls...to me it is almost impossible to produce "natural" pearls. Those are in God's Hands...

Keshi Pearls are cultured pearls...beautiful pearls... but they are not natural pearls.
 
After xrays, microscopy, weighing etc, many naturals never get certified. Most labs have little or no baseline data to compare each and every species. It's expensive, strict and time consuming.


And they are still at it:

http://www.ssef.ch/en/news/news_pdf/Bahrain2010May_tomographyl.pdf


In the rare event a mollusk forms a pearl naturally during juvenile rearing, it's still within a cultured environment, hence it's value is overshadowed by default.

At least for some keshi there are clues to look for already [LINK] and one might imagine that this kind of work has not been pushed to the last consequence yet - its limitations are yet to be defined.

I am afraid that those other pearls happening all by themselves are more mysterious still. 'Intervention' is a philosophical concept to them: pearls may as well be unaffected, their frequency only under question.

And even then... at least in theory pearl banks can / should be restocked up to whatever capacity of the given ecosystem. You wouldn't have young shells looked at before release, but banks culled. It isn't just theory and need not be poaching either - perhaps someone's idea of keeping a piece of landscape and culture float.

That definition of 'natural' and 'intervention' should get quite a bit more interesting to account for such things. Nevermind ogling the pearls ex post...


All in all, I don't see how pearls could be worth the trouble, even if Christie's is getting half of their worth.
 
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...we tried many methods of pearl production in many different species ...

Keshi Pearls are cultured pearls...beautiful pearls... but they are not natural pearls.

I have looked just about everywhere for an account [i.e. observation] of how keshi form, but no one appears to have bothered with them much until just about now. Haenni's report [same as above] appears to fill this gap with an educated guess:


[in caption, figure 2] "Keshi pearls from Japanese Akoya production. The
smaller ones are mantle pearls which grew as a reaction to
damage at the edge of the shell and in the mantle epithelium
incurred during handling. The small size is consistent
with the short period of time between the operation and the
harvesting."


and below on page 2


"It is interesting that these original keshi
pearls were found in the mantle tissue, and
not in the gonads that had received the
mantle tissue transplant. They therefore
cannot owe their formation directly to the
transplanted epithelium. That they are
always small has to be related to the age of
the shell, or more correctly, with the length
of time between the handling of the shells
and harvesting of the crop. The following
thoughts are deduced from the author?s
own observations and reflections and are
presented without having consulted the
extensive professional literature in Japanese;
should any of the ideas be similar, apologies
are offered. "



You do find keshi too [and rather nice ones at that!]. Do they fit this story?
 
Couldn't pearl growers simply poke the mantles of mollusks just enough ...

What you say sounds allot like Haenni's idea of how some keshi form [above], isn't it?

I wonder whether anyone has a record of the process at all - even in Japanese. What level of detail would be relevant [either for making or breaking 'conspiracy' - same difference] is another question.

SSEF's idea to date pearls sounds rather nice all of a sudden...
 
It would seem this is exactly what is taking place, especially in places like Indonesia, resulting in the flood of keshis.

That, or shoestring nucleation...

For the pearls deemed confusing at the buying end [GIA's lab note has a handful of examples deemed as such, looking awfully similar to all others] the question of whether someone could stay in business from tinkering with oddities alone, may be simply academic. Would hope that at the other end it is anything but.
 
Hi Douglas
Thanks for your experiments on all those shells.That adds a nice piece of info to the mix. It would take something more than what you did to stimulate pearl formation.

Your experiments aside, the rest of this is not directed to you. I think you are as honorable as it gets. You would never stoop to lying about pearls, because you are a scientist in service to the pearls and the harsh mistress of your conscience would kick your butt.;)

I am imagining that the Pearl Pirates who are now selling the keshi as naturals started about where you finished. They put forth years more of effort and invention to achieve a simple, hollow tool maybe like a syringe, with a dose of loose epithelial cells in it, that will puncture the mantle and then release the precise number of epithelial cells inside the connective tissue of the mantle before it withdraws. It sounds simple, but there are a lot of factors like how to gather and prepare the cells in what liquid solution, what is the right dose to get the sac growing and best placement in the mantle. How to increase the number of round keshi. (maybe the syringe method with liquefied epithelial cells actually produces rounder pearls because they can get together and form a round pearl sack and not have to form it from a slice.)

I base my idea on Elisabeth Strack's definition of how a pearl forms on page 116 of Pearls, 2006. Effisk put up a photo of her graphics and description somewhere around here.

Anyway, she says, "Individual epithelium cells find their way inside to the connective tissue (of the mantle), due to an injury of the ectoderm layer. The epithelium cells multiply by division and link together." They link into a sack. The pearl starts forming inside the pearl sack.

Spontaneous keshi have to form the same way since they are not formed from empty pearl sacks. The mollusk must have had some mantle damage for each spontaneous keshi.

Maybe the Pearl Pirates didn't even know how pearls form before Strack came out, but clearly, there is some science and planning to their current method, so the they must have learned exactly how to manipulate the epithelial cells to get not only pearls, but round pearls.

Just my imagination running away with me, but it sounds like it could be done.

Although manipulated pearls should never be passed off as naturals, surely they will develop their own price range- perhaps higher than beaded pearls, but lower than naturals of the same species.
 
I should have also included that Friedrich Alverdes is the father of the syringe method. He was the first to demonstrate that pearls only form when some epithelial cells penetrate into the connective tissue- and he demonstrated it in 1913 or so- with a syringe of epithelial cells.
 
Hi Douglas
I am imagining that the Pearl Pirates who are now selling the keshi as naturals started about where you finished. They put forth years more of effort and invention to achieve a simple, hollow tool maybe like a syringe, with a dose of loose epithelial cells in it, that will puncture the mantle and then release the precise number of epithelial cells inside the connective tissue of the mantle before it withdraws. It sounds simple, but there are a lot of factors like how to gather and prepare the cells in what liquid solution, what is the right dose to get the sac growing and best placement in the mantle. How to increase the number of round keshi. (maybe the syringe method with liquefied epithelial cells actually produces rounder pearls because they can get together and form a round pearl sack and not have to form it from a slice.)

We tried that already, several times. We used sterilized saline solution to produce a liquid-mantle solution, we tried picking up small pieces (less than 1 mm big) of mantle and injected them in many parts of the oyster's body (abductor muscle, mantle, gonad). Never raised tissue in a lab tough to use for these experiments.

We never wanted to produce keshis...nor say we produced "naturals"...but we wanted to have a better, deeper understanding of what it takes to produce a pearl naturally. The more you understand, the better your chances at culturing pearls withing our "impossible" oysters (with the Rainbow Lip you need all the help you can get).
 
The smaller ones are mantle pearls which grew as a reaction to
damage at the edge of the shell and in the mantle epithelium
incurred during handling. The small size is consistent with the short period of time between the operation and the harvesting."
and below on page 2
"It is interesting that these original keshi pearls were found in the mantle tissue, and not in the gonads that had received the
mantle tissue transplant. They therefore cannot owe their formation directly to the transplanted epithelium. That they are always small has to be related to the age of the shell, or more correctly, with the length
of time between the handling of the shells and harvesting of the crop. The following thoughts are deduced from the author?s own observations and reflections and are presented without having consulted the extensive professional literature in Japanese;
should any of the ideas be similar, apologies are offered. "
You do find keshi too [and rather nice ones at that!]. Do they fit this story?

Not in my experience...handling is of no consequence. Experiments performed on "damaged" oysters (broken margins) did not yield any pearls above the others. Our results showed: stunted growth and higher mortality.

Maybe that is true of the Akoya, but not for the Rainbow and Black lip oysters. I believe the true cause of these natural pearls are due to external biological agents: VIDEO. It is in Spanish...but you can use your eyes to see...
 
Not in my experience...

'Guess that's a big part of the 'keshi' mystery: how to start pearls keeps getting re-invented from a mysterious list of possibilities!

[speaking of old experiments: Linee had a patent for pearls - he used plaster, and got many small pearls from each North Sea mussel. I do not know too many details about the process; the man had no business sense and this story of early pearl cultivation is now a teaching example of how to bury a perfectly good invention for a few centuries.]
 
That is an answer to my original question in this thread. Why wouldn't this work? Your data is of great value- and you are such a well of data!

The keshi-called naturals-are turning up in what species? It seems p maxima for sure. Maybe that species is a little more amenable to induced pearls.

Someone is inducing very round keshi pearls in the mantle and calling them natural. The market is noticing them, so the question is how are they doing it? It must involve getting a pearl sack started.

That's why I said they must have spent so much time and money figuring out how to induce a very round keshi, let alone get a pearl sack started. Also that Friedrich Alverdes claims he did it with a syringe. Was his method flawed or invalid? I got that from Strack, (p114) so I have not studied up on him independently.
 
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