Treatment of White South Sea Pearl

[Lagoon Island Pearls]

Dave, have you also compared the mineral oil to , say, corn oil?

I've not tried any of the vegetable oils. Rancidity is the main reason because bacteria can thrive. Conchiolin is consisted of glycoprotein and polysaccharide.

Polysaccharide and argopectin make agar, a well known culture medium on Petri dishes.

Add vegetable oil to conchiolin you'll get gelatine and sugar, and that's not good. In fact, I'm quite certain a lot of antique pearls that peel, wear or yellow are microbial, not necessarily physical.

Whoever said oil and water don't mix, doesn't understand chemistry. Emulsions are common. Milk and butter are good examples. The idea of treating pearls is to displace, not replace water. The last thing anyone wants are milky pearls. If the pearls are dry, then treated, you run the risk of building internal pressure which can cause cracking and peeling.

There seems to be a few reasons why some would choose to treat. The first being to change the appearance and the other is to stabilize and preserve the pearl or a combination of both.

Mineral oil does not appear to react much other than gather dirt. While it might improve the appearance somewhat, it's by no means a preservative.

I have experimented with other agents on shells. Archaeologists and conservators use polyethylene glycol (antifreeze) to replace lost longchained mono and polymers in artifacts. This works well as a preservative, but is water soluable, so it's not practical for pearls.

The other agent is glycerine, which is often used in skin care. I preserve crabs and other specimens with a mixture of glycerine and formalin. The glycerine slowly permeates outward and gives the specimen a nice shiny and colorful appearance, as opposed to cloudy dull like so many old shells do. In this case, one agent needs the other and I don't think anyone would want to wear pearls treated in formaldehyde.

On asthetics, I have also tested hydrogen peroxide, both light and thermally activated but with mixed results. The purpose of bleaching has been touched on many times before here, but suffice it to say, it's a destructive method. The closest I came to treating anything with reasonable results, was a mixture peroxide and glycerine.

Which brings me to my final point. Why treat at all? Although there can be a host of reasons, to me, the main reason to treat is to improve the quality of inferior pearls. For someone striving to become commercially viable, it makes no sense whatsover to attempt to break into a difficult market with inferior pearls. It is incumbent upon me to produce the best quality possible from the mollusc itself, not after the fact.

For huge corporations that produce pearls by the tonne, it's reasonable to maximize profitability by treating pearls as a value-add. The few dollars per carat can add up to considerable amounts at the bottom line. For the small operator, those returns are diminished and a liability.

 

[R&B]

Inspirational Dave, Inspirational.

 

[jshepherd]

Which brings me to my final point. Why treat at all? Although there can be a host of reasons, to me, the main reason to treat is to improve the quality of inferior pearls. For someone striving to become commercially viable, it makes no sense whatsover to attempt to break into a difficult market with inferior pearls. It is incumbent upon me to produce the best quality possible from the mollusc itself, not after the fact.

For huge corporations that produce pearls by the tonne, it's reasonable to maximize profitability by treating pearls as a value-add. The few dollars per carat can add up to considerable amounts at the bottom line. For the small operator, those returns are diminished and a liability.

The answer is simple. It has nothing to do with inferior pearls. It is about making the pearls as beautiful as they have the potential to be.

I don't think anyone here would consider Sea of Cortez a huge corporation, considering they produce only a few strands per year at most. Yet they use mineral oil. Why? They do it because they realize that it makes their beautiful product even more beautiful, and it is the same sort of thing that has been done to pearls for thousands of years. So why sell their product short?

Furthermore, after drilling a strand of pearls, they need to be polished. Anything less would be selling the customer short.

 

[Lagoon Island Pearls]

The answer is simple. It has nothing to do with inferior pearls. It is about making the pearls as beautiful as they have the potential to be.

I don't think anyone here would consider Sea of Cortez a huge corporation, considering they produce only a few strands per year at most. Yet they use mineral oil. Why? They do it because they realize that it makes their beautiful product even more beautiful, and it is the same sort of thing that has been done to pearls for thousands of years. So why sell their product short?

Furthermore, after drilling a strand of pearls, they need to be polished. Anything less would be selling the customer short.

Farbeit would I sell SoC pearls short and it's unfair to suggest that as my intent. I merely repeated what Douglas said about his reasoning for using mineral oil. He's also made it very clear, that his pearls are not treated in any other way.

Actually Jeremey, it was you who said "Bring out more of a white color into the grey pearls, so even on the low end they'll be able to sell them" furthermore, went on to say "Yellow is not a very profitable color, so what they'll do is... they'll add a little red dye"

http://www.youtube.com/watch?v=yIBlEeKJxDw

Clearly, those are post harvest treatments intended to upgrade the lot. All pearls are beautiful in their own way, but replacing inherent beauty with perceived beauty is a subjective issue, and nowhere nearly objective, especially when undisclosed.

 

[jshepherd]

What they'll do is bleach them and then add red dye.

I'm not arguing that pearl treatments should not be disclosed. I personally made that documentary about that very thing and have included it with orders to customers for years. When I made the documentary and before Pearl-Guide, very few really knew what bleaching and pinking were all about. I am arguing with your assertion that treatments and/or polishing is just about making inferior pearls better and that they don't need it. For small producers like yourself and Douglas who aren't competing in the commercial pearl market, I feel you would be selling your pearls short by not doing the things to bring out the most beauty. It is about making the pearls as good as they can be, not making something inferior superior.

 

[Lagoon Island Pearls]

Perhaps we got off on the wrong foot in this discussion by my use the word "inferior". I gather you viewed my comment as suggesting inferior meant unfit at any price and far below minimum grade. It's not. I was merely comparing them to high quality and most the desireable pearls, because that's a farmers goal... to produce the best possible quality from the outset.

I made it very clear, my intention is to break into the market at a high level of quality from organism itslef, not something remanufactured from a mediocre source. They are two entirely different things. I also made it abundantly clear, it's a reasonable practice for the big guys to value-add their product. For a little guy to buy the equipment like a thermally controlled lab, tumblers, chemicals, flasks etc simply isn't practical for a handful of lesser grade pearls. To suggest not doing so is a disservice to ourselves completely misses the point.

 

[jshepherd]

Yes, that is they way I understood your use of inferior.

I wouldn't suggest that a smaller producer invest in those sorts of things, except maybe a tumbler, which can be purchased on Cabelas.com for about $50. I am specifically referring to polishing, though. Not bleaching, heat treatments, etc. I think pearls should be polished as they always have been. It brings out the beauty of the pearl. If a pearl hasn't been polished and lies against the skin, it will eventually become polished, albeit unevenly, by wear - hence my comment about rubbing a pearl on one's forehead.

 

[pearlescence]

Hence also, Jeremy, the old saying about pearls should be worn and wearing pearls improves them. Presumably.

 

[pearlescence]

It occurred to me that south sea pearls themselves are not natural - they are cultured, so the process of producing them could be considered a treatment - it is certainly a process. Therefore over-worrying about some buffing etc post harvest is illogical.

 

[cookierookie]

does it fade?

does it fade?

what I am most concerned about after reading this thread, is that with maeshori treatments done to South sea pearls, is the change in lustre permanent? if it isn't, how long before it starts to fade?

does maeshori also affect the lifespan or structural integrity of the pearl? coming from a materials engineering background, i well know that exposing something to extreme heat and cold will most certainly change its structure -- sometimes reversible, sometimes irreversible.

any inputs would be greatly appreciated.

 

[cookierookie]

Pearls that have undergone maeshori has made it harder for us who sell pearls that have not undergone this treatment.

We had some potential clients say that their SSPs have mirror-like luster and ours is ONLY satiny. SSPs are known for its soft, deep, silky-satiny lustre, not mirror-like lustre. hearing this does upset me, especially when these clients never disclose of the maeshori to the jewellers they sell to. I think it is very important that every single treatment is disclosed, whether it is pre-treatment, polishing, dyeing. In the end it is all semantics and the most important thing is the consumers know what they are buying and are really making an informed purchasing decision.

This article that was published in the Solitaire magazine last year says that the polishing that maeshori does is not permanent (this article is about FW pearls). Is it the same for SSPs?

http://www.solitaireinternational.com/images/2110112304pearl_update_oct11.pdf

 

[R&B]

As a grower of South Sea Pearls I am offended but respect your right to say it Wendy.

I'll not be re-drawn into this discussion.

 

[pearlescence]

I'm sorry you are offended R & B..that was never my intention. I only pointed up an incongruity after it occurred to me.

 

[Artpearl]

Thank you tyren, you said exactly what I was thinking on this topic. From a consumer perspective, disclose everything and let me decide. I personally lean toward the minimal touching of the natural pearl as possbile.

I want to thank you all for having such a wonderful and honest discussion. Bravo, I know I was in the right place to continue my learning on pearls. (haven't finished reading this most interesting thread yet)

As an ordinary person on the street looking to buy a strand of pearls, I'm for DISCLOSURE DISCLOSURE DISCLOSURE. I think there is room in this world for non-treated pearls, pre-treated pearls, post-treated pearls, well-treated pearls, badly-treated pearls etc., but the consumer should decide which ones he wants and what he wants to pay for them. But right now, I have no way of knowing whether a strand costing 30k ("excellent luster and sought-after white-with rose overtones") is good value (whether it will deteriorate because the luster/colour has been treated). And what I cannot value, I will not buy.

I reckon a continued lack of consensus on disclosure standards will damage the industry eventually because consumers like me will not buy what we have insufficient information/ understanding on.

The following from Jeremy's post caught my eye (Day 11 narrative):

"Michael talked a bit about pearl treatments, and how Paspaley was preparing to launch a campaign on treatment disclosures. GIA could now test for any and all treatments, and consumers should have a right to know. He intimated that anything coming out of Japan today had been subjected to treatments of some kind, and these pearls should not be as valuable as pearls completely in their natural luster state."

I think disclosures of treatments are the way to go, but to make the disclosure meaningful to the consumer, I think the industry participants need to define what does and does not constitute treatment in the first place (eg., polishing/ oiling/ drying etc).

And since I'm on that point, I don't really care as a consumer whether it is mineral oil or the oil on someone's forehead that is applied to the strand of pearls I buy, but I do want to know if the oil serves to protect the nacre or it will damage the pearls in the long run.

 

[CLICLASP]

It occurred to me that south sea pearls themselves are not natural - they are cultured, so the process of producing them could be considered a treatment - it is certainly a process. Therefore over-worrying about some buffing etc post harvest is illogical.

It seems to me that it is the core question of what is treatment , what is natural.
I think shades and differences in definitions are important, no one can make confusion between: washing our face, making up our face and cosmetic surgery on our face.
Therefore, there is a difference between letting pearls in oil and bleaching and/or dying pearls. The answer seems to be in disclosure.
When we know about what we buy, we can appreciate the pure natural beauty/ value of things, don't we?

 

[Artpearl]

As cliclasp mentioned, we can all appreciate the pure natural beauty of things/Pearls. I have not doubt that this applies to all of the readers and contributors on this site.

The general population or consumer of pearls will vary greatly in what they are looking (quality, shine, colour) for and what they are prepared to pay but will all agree in having disclosure available.

RR, I really appreciate your efforts and work as a small farmer. As a pearl lover, I would like to see that the small and larger operations not only survive but thrive.

On a personal note: Happy 2nd anniversary (loved your blog and photos). Many happy years ahead.

 

[Sutrisno]

Wow, this thread has exploded since i last checked! I love the way each one of you made your points. I am somewhat with jeremy on this one. I don't mind treatments as i place it under the same value as the way gems are cut/polished/treated/crafted.

So it becomes a matter of having a masterful cut, or a crappy one that will actually devalue it. Though i always felt that being an organic product, pearls shouldn't be expected to last forever. I think disclosure is important but i have heard of people being offended with the claims of pearls losing its colour and deciding to not buy pearls. What do you do then as a producer?

More important to me though, what is a healthy pearl treatment? Using what kind of oils? Silverware and gold jewelry requires a bit of polish now and then. What is the standard for pearls?

 

[CLICLASP]

We cannot really compare cutting/polishing / ... / stones with pearls treatment,
for exemple, heating or worse filling rubies cracks for red glass is also a treatment and those cannot be compared with precious stones without treatment,
We still have to keep some shading, don't we?
hi gemologists over there, what's our opinion ?

 

[Sutrisno]

In a sense no, because i think cutting a pearl pretty much destroys it. But that is the basic ' maeshori' of gems. Don't see much uncut gems around. It's like mascara and lipsticks, different things, and procedures, but it is also the first choice of improvemets of the lashes and lips respectively. My two cents.

 

[cookierookie]

under the CIBJO pearl guidelines, i would just like to say that it is clearly stated that pearls that have gone through maeshori or any treatment must be disclosed by the seller.

But if a wholesaler is unsure (i have met those who really have no idea) of what they are selling, how would the retailer know what they have been sold? the Pearl book by CIBJO is free for download on their website. my two cents