Quality factors of pearls

[Marianne]

Hi ericw. It would be good to see photographs of your findings as you carve various pearls. Art and science are not very far apart!

 

[ericw]

Littles stones, bad varnish.. Not a question a science, at time, but many cheatings to write "pearl" on the webstores.
And sellers don't like at all when I ask them accurate questions.
Sometime, treatments are not the best way to improve pearls : I have tried some personal treatments to lustre (without bringing anything foreigner in the pearl' structure) soft pink but a little dull "biwa" pearls. In fact, these pearls were dyied. The colour has desappeared, but the final result has been so much shining pearl than the first !
Now, the question is how many time the brigthening will last.
Thank you to ask photographs, but I'll show something when i'll be satisfied by my results. Soon, I hope.

 

[amti]

I'm very curious on the shining of the pearls. What did you do? Would love to see before and after photos. I wonder if you rubbed away one of the layers of nacre.

 

[ericw]

Hi Amti,
Yes, I have rubbed away a few layers, with a process I am studying. A chinese patent already looks like my idea, with some differences, anyway.
The best of such a process is to peel softly, evenly, the less hard layers of the pearl, which are dull, to find better. But each pearls are different and also the result.
Unfortunatly, I have not so good camera to well show the difference. Just you can believe me... Anyway, I must buy one to show my work.
It's very difficult to make good pictures of carved nacre !

 

[amti]

What are you using? I have tried picking away on a vintage baroque akoya which had the tip broken off and saw how pretty some nacre was under the top surface. However, it is tricky to try to get the top layer removed evenly so the layer underneath is even. It might be easier to rub it off, maybe with a microfiber cloth or something very slightly abrasive that won't leave marks. A nice camera is probably worth the investment. Learning to use it is just as important too!

 

[ericw]

Learning to use a modern camera is so a big problem than I am not modern myself !.
About pearls, I use several process, chemical or mechanical, according to whether the pearl react, and each pearl is different.
First, it's not possible to be sure to find better layers inside.
To pill pearl can also show the nucleus, by transparency of a thiner nacre.
So, I think that pearls are often dull because the last layers left by the shellfish, just before pearl is harvested, are not the best, the time to stop this growth being incertain.
The most important is to pill layers regularly, without dig through. A delicate work it is.
You can find discs as sponges, more or less abrasive, in dental technicians' furnitures, which are efficient to work carefully pearls one by one.
It's sometimes good, also, to use polisher discs applying a little more to heat up the pearl, just under the tool. The mirror effect is often intensified by this way.
Xylene, one aromatic Hydrocarbon, reinforce shining rainbow's effect, so, but if the pearl have the smallest scratch, it can be killed any time (and always with toluene)... And I think it's not lasting, but sure, just smell very bad a long time.
Now, when a pearl is dead, is dead. I have tried to find good nacre under destroyed, but even deeply, I have not found any better nacre.

 

[amti]

Thank you, it's very interesting. I'll have to google the chemicals later and look into it again. I'm not sure I want to go through an intensive and tedious process right now.

 

[Cicadalady]

Xylene and toluene are not chemicals to be taken lightly! Care is required when handling them as I'm sure ericw knows.

 

[ericw]

Yes, of course. I know and I have not brought that. Thank you for it.
Anyway, there 'are hazardous treatments I don't recommend !

 

[ericw]

Just to report my observation of the day : less than a 0.03mm thick layer of good nacre is suffisant to give AAA glow to a dead pearl... It's also my sad surprise of the day.