Need Everyone's Opinion on these cross sections

TomMStern

Member
Joined
Sep 25, 2008
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Hi everyone,

My father, Dr. T.K. Stern, recently went on a trip to Hong Kong and found some "antique" pearls in a shop. Apparently he had been looking around when he found that the owner had a little bag of discarded old pearls sitting in one of the shelves. Allegedly they were very old and came from some fancy tiara and he ended up purchasing them.

Whatever their real age or story may be, they have definitely experienced a substantial level of decay, with layers of nacre disintegrating, etc. Very, very bad shape. So, to clean them up, I have developed a working and polishing process to remove the decaying layers and restore the luster. I did this to several of the pearls, making sure to try and preserve their original shape.

In this process, I discovered that after removing several layers with decay in between, I would hit what I thought was a good layer of nacre, which I would then expose to finish the restored pearl. However, after a few more, I discovered that several finished ones, where I had worked to the good layer, appeared to be the same standard size.

I am now suspicious that these are not antique, but may just be some very mistreated bead cultured pearls where I have ground the nacre down to the bead.- Possible freshwater pearls used as bead inserts...

In the photos attached, I include two cross section shots and also some shots of the pearls after working.

I would appreciate everybody's feedback on this. I've seen a lot of x-rays and cross sections/ cores of new pearls, but I am afraid to reach conclusions on these because I am not sure of their age, and what the duration of their age could imply in regard to their nacre formations.

If it remains questionable, I will take take the gamble of having them tested. If they are natural, coupled with their cool background story, I think they will be very valuable.

Ok, Thanks to everyone.
 

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Old pearls

Old pearls

To me, it looks as if these pearls languished in terrible conditions, in which the outer layers fractured and dirty water got between the lamellae of natural pearls. As you say, though, the phenomenon could be nacre splitting away from a bead nucleus...although it does seem to be pearl all the way through, not cut shell.

I think a high resolution macro lens would allow enough enlargement of the photos to be more sure about the center layers. You might try a 60 lens on a big Nikon.

My suggestion is to send one or two examples to GIA for analysis, which will also tell you by manganese content whether the pearls are fresh or saltwater.
 
Would venture a thought:

I find it intriguing that the nacre layers of the 'inner pearls' appear concentric - which suggests that those can only be pearls themselves [the image of the one on the left is not clear at all, only the right one]. It would be interesting to hear some educated guesses of what may have interrupted the growth process - naturally or not, to produce those protein-rich gap layers, or whatever they are.

I remember there has been some discussion here about such growth patterns observed in natural black pearls [Douglas', I think]. And about pearls used as nuclei - more or less experimentally - a while back, too. And how less refined lab imaging could get confused by such examples, etc. All very interesting... These ones may add to that story.
 
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Valeria101 and Dad, Thank you for the thoughts. These things are turning out to be quite a mystery as the discussion surrounding them continues. I will take the next step and bring them with me to GIA so we can see what some enhanced analysis yields. I will post the findings after my trip.
 
Opinion

Opinion

Valeria101 and Dad, Thank you for the thoughts. These things are turning out to be quite a mystery as the discussion surrounding them continues. I will take the next step and bring them with me to GIA so we can see what some enhanced analysis yields. I will post the findings after my trip.


Son,

Has GIA reported yet? I'm sure they are natural. What I am not sure of is whether they are freshwater or saltwater. In China, for example in Ming and Qing Dynasties, the number and quality of pearls which could be worn by each rank of concubine or royal consort were strictly prescribed by imperial rules. Since you studied in University of Suzhou, you know more about it than I, so please read the original Ming Annals. Lesser pearls came from rivers in Manchuria usually, but the top rank pearls came from the Southern Sea, of which you are royal datu.

So, I'm interested in the manganese content, which in relatively fresh pearls can distinguish between fresh and saltwater. In ancient pearls, such as these, I wonder if manganese content is a reliable indicator.

Love,
Dad
 
Hi All,

I have not seen the report yet, but information came down the line from GIA NY where these were tested, that they are all bead cultured! So, my suspicions were correct and I was, in fact, getting down to a bead nucleus. I will post more information later if there are any interesting details in the report. I hope everyone will continue to enjoy these photos for scientific purposes. For me, I continue to appreciate it as a rare opportunity to explore the interior of a pearl and become familiar with certain anomalies in nacre development, etc. Ok, that's all for these pearls now!
 
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