Treatment of White South Sea Pearl

[tyren]

I've been looking to buy a strand of white SSP necklace and I always ask sellers if the colour or lustre of the pearls have been enhanced or treated in any way. I'm more than a bit perplexed by the answers I've been given and am hoping that the experts here would be able to help.

A seller had said that almost 100% of all SSPs have been bleached to achieve a "balanced" colour and therefore the bleaching is not even considered a discloseable form of treatment. Another seller said white SSPs cannot be treated in any way or form and therefore I should not even be asking for a representation that SSPs have not been enhanced or treated.

I do not believe either of these sellers.

But I'm interested in finding out whether (i) it is reasonable for me to get a representation that the colour and lustre of the SSPs have not been enhanced or treated in any way; (ii) there are any acceptable forms of treatment that white SSPs are usually subject to which would not cause the SSPs to deteriorate over time; (iii) there is an easy test I can subject the pearls to to see if they have been enhanced or treated without having to bring the pearls to a gemologist.

As further background to my questions, I've noticed that the good quality SSP strands I've seen about 5 to 10 years ago tend to exhibit a beautiful satiny warm lustre (which I've come to associate with SSPs) with individual pearls showing very very slight variations in lustre and overtones, but the recent strands I've seen appear to exhibit a sharp metallic, often uniform lustre. I can't seem to reconcile how artificial some of these strands look and therefore my questions on enhancements. Just to clarify, I believe I can differentiate between SSPs and premium freshwater pearls (which can exhibit a beautiful sharp lustre), so it's not like the sellers are trying to deceive me into buying freshwaters passed off as SSPs.

Thanks in advance!

 

[Agustus-Collection]

Hi,

genuine south sea pearls are NEVER treated in any way.

South Sea Pearls are available in many shapes, colors and or overtones.

Just to clarify, to get a full matching strand together with south sea pearls ( regardless the color ) it can take the seller several years, depending a bit in shape and size of the pearls.

BUT there is no such thing of bleaching whatsoever !!!

You may post a picture of the strand your are interested in and we may can help you to determinate if they even what they say they are. I am really curious why the seller told you about bleaching and furthermore why it is not necessary in that case to describe them as treated.

 

[jshepherd]

If white South Sea pearls pass through Japan, they are going to go through maeshori. If a company in Indonesia or Australia, for example, sends their pearls to Japan to be matched and drilled, you can almost certainly assume they are going through maeshori.

Depending on the type of maeshori (factories vary), this could tone the color and/or enhance the luster.

Golden South Sea and Tahitian don't go through maeshori in Japan (yet).

 

[tyren]

Thank you both for your helpful comments. I'm reading through some of the discussions on Maeshori treatment in this forum and I think it's all becoming clear to me now that the sharper metallic luster I've been seeing in a number of strands would have been the result of Maeshori treatment.

In particular, I remember looking at an Autore strand and thinking that the luster looks enhanced, and further wondering why there is no mention in the Autore certificate that the pearls are not treated in any way.

Given that there appears to be different methods of Maeshori and it appears uncertain how each type of Maeshori treatment may affect the pearls in the long run, I'm really sad and alarmed that there is no clear(er) disclosure of this in the SSPs that are sold. Also in my personal and very humble opinion, the resulting luster looks completely unnatural for SSPs as they are starting to resemble the luster on akoyas and treated freshwaters.

 

[Caitlin]

I don't see why South Sea white pearls that go through Japan must go through maeshori. How does it help the SS pearls? It doesn't. In fact the CHANGES not only the luster, but the porosity of the pearls if they have been "pre-treated" by maeshori that includes bleaching. Now, I suppose that akoyas may need some kind of washing and heat pre-treament, to toughen up those flimsy skins, but extending it to ALL white pearls seems to be kind of nuts, to me. Do the maeshori processors have a lock down on every pearl through the laws of Japan? Or is there some flexibility there?

Not only that, but why do they need a proprietary treatment that is not disclosed? Not even the "pre- bleaching" is disclosed. What kind of legal razzamatazz is that?

Well, it always has been one of the missions of this site to disclose every pearly secret we can find, so what is the real truth about maeshori? What is the whole story? The history? How was it discovered that akoyas do better if "pretreated". Does pre-bleaching HAVE to be part of it or was it wiggled in there by corporate fancy-dancing?

Are these kind of questions this post makes you wonder about?

My favorite bit of fancy dancing: https://www.youtube.com/watch?v=1c8XLJ9MEhk

 

[jshepherd]

Maeshori does help the pearls - aesthetically. Overall, the pearls will have a better, consistent tone and better luster. This means the wholesaler will be able to sell them for more and the retailer will be able to sell them for more.

Tyren,

South Sea pearls can indeed have the sort of luster that makes them appear to be treated, even if they aren't. The two South Sea strands that are in this photo were composed of loose pearls from an auction lot. They haven't been to Japan and they haven't been gone through maeshori.

The maeshori technology is proprietary and can definitely vary from one processor to another. Maeshori is supposed to be used to prepare the pearls to receive some type of treatment or another. Mae = pre & shori = treatment.

 

[jshepherd]

But I'm interested in finding out whether (i) it is reasonable for me to get a representation that the colour and lustre of the SSPs have not been enhanced or treated in any way; (ii) there are any acceptable forms of treatment that white SSPs are usually subject to which would not cause the SSPs to deteriorate over time; (iii) there is an easy test I can subject the pearls to to see if they have been enhanced or treated without having to bring the pearls to a gemologist.

First, I wanted to note that maeshori is not the same as bleaching, so in a way one of the sellers was correct.

1. Yes. It is reasonable, but may be difficult for some sellers. Most sellers don't buy hama-age lots or go to producer auctions. The buyers are nearly exclusively processors in Japan.

2. Maeshori will not cause the pearls to deteriorate over time.

3. No. Also, a gemologist wouldn't be able to help you.

 

[Caitlin]

Maeshori does help the pearls - aesthetically. Overall, the pearls will have a better, consistent tone and better luster. This means the wholesaler will be able to sell them for more and the retailer will be able to sell them for more.
...
The maeshori technology is proprietary and can definitely vary from one processor to another. Maeshori is supposed to be used to prepare the pearls to receive some type of treatment or another. Mae = pre & shori = treatment.

That means the goldens and blues don't have as consistent tone or better luster? That they have looser skins? The more I learn, the less I understand... Are the blues redyed to repair the maeshori done to them?

Then what is/are the treatment/s applied after the maeshori, more bleaching? the pinking,or is the pinking a pretreatment too, since it is also undisclosed?

I avoided thinking about this for years, because akoyas just aren't my thing. I do understand they are the most popular pearls in the world at this time and hope my questioning does not destroy sales the world over, or even, locally, but I can't help wondering.....

2. Maeshori will not cause the pearls to deteriorate over time.

Not even if it includes bleaching? Then why do so many old akoyas look so old? They got post maeshori bleaching?

 

[tyren]

Jeremy, thank you for drawing my attention to the important point that not all SSPs with sharp metallic lustre are Maeshori-treated. The photos drove home the point brilliantly.

If such perfection exists in nature, then it should be celebrated and marveled at. But unfortunately the seemingly common but undisclosed Maeshori treatment has made it difficult for a consumer to tell between nature's miracle and the machinations of capitalism.

I don't think I'll have an issue if there was transparency/ consistency around the process, assurance that the pearls which have undergone Maeshori will not deteriorate with time, and consistency in the way such treatments are disclosed to potential buyers like myself. In that way, I can decide whether I want those pearls and how much I want to pay for them.

Which brings me to the next question - is it possible to detect Maeshori treatment in white SSPs? I believe a GIA cert for cultured pearls has a section on "Treatments" - if it states "none detected", does that mean the pearl has not undergone Maeshori?

 

[jshepherd]

Caitlin,

Maeshori doesn't necessarily mean that anything has been done to the color. In the strictest sense, even washing the pearls is a form of maeshori because it is a pre-treatment process.

Tyren,

No, I don't believe GIA can detect most maeshori. If the maeshori is destructive, yes, I think they could tell. But if not ...

The problem with consistency of maeshori is that different processors process in different ways. Years ago, I would mostly deal with the smaller processors in China when buying freshwater pearls. I did this because prices were better and it was a lot easier to have a good relationship with them versus some of the larger operations. Now, I only deal with a few select companies that have what I consider to be the best maeshori and treatment technology. When freshwater pearls turn chalky it's because they weren't properly treated.

 

[KarinK]

Hi Tyren,

I feel like you do about the Maeshori. I prefer to know if the original appearance of the pearl has been altered / enhanced in any way. Unfortunately, as far as I know, maeshori is not considered at treatment and therefore is not covered in the section of treatments. So 'none detected' does not include any possible maeshori of the pearls.

- Karin

 

[Caitlin]

It would be nice to know.

Douglas discloses that he washes, then soaks in mineral oil for an hour or overnight, I forget how long. But then there is no further treatment The mineral oil itself seems to be a medium that completes the cleaning of the pearls. So that is maeshori? (just sticking to the meaning of the word) Washing is pretreatment and oiling is treatment? Or pretreatment?, So why is Maeshori called 'pre-treatment'?

Do I remember some freshwaters you said only had a bit of corn oil on them? Those first Freshies? A bit of oil is not a treatment because it does not have a chemical effect as bleach does and Douglas, who does use oil, cleans the oil off, or mostly off, taking whatever traces of slime may have been left?


One thing I hear loud and clear, is you use companies that produce high quality pearls, even if you are not sure exactly what the maeshori was. The quality of the pearls is clear even before maeshori? And the processors process accordingly?

 

[jshepherd]

Oil will improve the luster and is part of polishing - a treatment. Freshwater pearls are tumbled in pieces of corn husks that have oil infused in them. This is typically the last thing that is done to them. This does also serve the purpose of cleaning the pearls (removing pearl dust, etc).

Maeshori is called pre-treatment because that's the meaning of the word. In Japanese, 'mae' means pre or before and 'shori' means treatment.

 

[Caitlin]

I am sorry I seem so difficult. I do understand the meaning of the word- literally- pretreatment, So in Sea of Cortez pearls the pre-treatment is washing, the treatment is oiling. Does oiling have to be disclosed? I know Douglas does disclose it.

Maybe that is why some pearls get better with wear, the old adage that skin oils are good for them might have a grain of truth? Aren't oils a bit acidic?

oh, sorry, sorry, sorry. I just hate it when I don't understand something well enough to teach it.

 

[Amanda]

When freshwater pearls turn chalky it's because they weren't properly treated.

What do you mean by "turn chalky"? What causes this? How long does it take to happen?

 

[Caitlin]

You will probably never see chalky pearls, they only have a few in the cheap pearl tents at the gem shows, any more. Maybe eBay has some. LOL. I had a few a long time ago that got chalky in the drill holes when strung on wire, though the surfaces were lustrous. They probably get powdered and put into makeup and bath salts as hardly anyone would buy them.

 

[jshepherd]

Oils are considered good for pearls and it's true that they can get more lustrous with wear. I haven't heard anyone other than Douglas talk about oiling the pearls. Most of the time it is just referred to as polishing.

Turn chalky - lose their luster.

It really depends. If poorly treated, it can happen almost immediately or in just a few months.

 

[Amanda]

Thanks Jeremy and Caitlin - I'd not heard of that before.

 

[CLICLASP]

I rate this thread 5 stars, PG is definitely a wondeful place to learn and share infos from each other, thanks to Jeremy and Caitlin for being so generous in sharing infos

 

[tyren]

Thank you Jeremy - the information you provided was really helpful.

Caitlin, the questions you raised reflect those I have as well, and i really appreciate your candour. The more I ponder over the questions, the more my head spins!

Thank you again to all who replied, I learnt infinitely more posting one thread on this forum than all the man hours I spent speaking with pearl vendors.