Polishing natural pearls (kima/tridacna)

dmj

pppp pearl
Joined
Jan 17, 2011
Messages
443
Hey Guys

The first natural pearls i ever got where tridacna, i found 6 between 5 and 25 ct in the house of a old indonesian woman who lived in Indonesia somewhere 100 years aggo when indonesia was still dutch kolonial and she took the pearls with here after she moved to holland. Here kids asked me to help getting all the antiques out of the house and if i wanted to have all the gemstones etc

When i first got my eyes on the Pearls i thought it where just old no more luster Pearls. (5 years jewellery school never seen others than culture :s) anyway i took them simply because the old woman had them stored in a verry nice box and al the amazing opals and emeralds she had where just laying around so this had to be something more special.

Now 5 years and a big collection of natural pearls later i was looking at the pearls because there was flame in them only they looked bad and i thought well they are free anyway so Lets try polish them with leather and diamond paste and after that on normal polishing wheel for jewelry now the one i did looks way better has a amazing flame and fine for jewelry

Long story now the question :) I still have 5 to do only im not quit sure if its oke to polish them and if its oke am i doing this the right way or are there better methods ?

Will make pictures of the flames somewhere soon when i have time they just look like any other kima flame tridacna Pearl ;)

Thanks
Dani
 
Hi dmj,

I am very interested in your method of polishing the natural pearls. Where did you buy the diamond paste from. It sounds like a very good method and I do hope other people that know so much more than I will come in and give their opinions or try it out for themselves. I would like to try in on some natural pearls I have that would possibly benefit from it. Often with old natural pearls one or two nacre layers may have been lost in part so your method intrigues me.

Come on you experts. Give it a trial. You must have pearls you could use. Say use freshwater pearls as trial pieces. If I can get my hand on some diamond past I will be trying it and naturally trying it on a pearl I can afford to lose first.

Please dmj do give us more details about how you went about it. How you held the pearl while buffing with paste on leather or however you did it. I am really interested.

Dawn - Bodecia
eBay Seller ID dawncee333 - natural pearl collector and all round pearl lover.
http://shop.ebay.com/dawncee333/m.html
 
pictures? did he say pictures? (ears pricked up like my dog!) yes please! i love natural pearls! and tridacna are so interesting!

- jodie -
 
I think you can do anything if you disclose it. You were actually removing some of the outside material? Just disclose it. But it also sounds intriguing since you like those carved stones. I bet a carved or shaped tridacna pearl. would be an experiment worth trying.

Dawn, an interesting way to "peel" pearls? !!! I know just what you mean, hope you try it if dmj shares his techniques . I would think it would work better on salt water pearls than freshwater, though.....
 
Using chemical compounds on natural pearls is an excellent way to devalue them. It's like old coins or other antiquities. Sure, it looks pretty for a while, but the surface has been irreparably damaged. Most polishing compounds contain substances like oxalic acid, which slowly degenerate the underlying layers after the fact.
 
I thought I was talking about diamond paste. I wasn't thinking there were chemicals in it, but I am an amateur. If you have a natural pearl that is all grody and yucky, I was thinking a mechanical paste might work as well as a peel with a knife. That is my imagination with no basis in reality, but why put chemicals in a diamond paste? Can you explain that a bit more?
 
Yes i was also afraid they would damage the laters under the pearl only because it was already bad looking i thought well Lets try what they Will do and for now they look amazing no idea whats best Only know That yesterday nobody liked my tridacna pearls and today somebody gave me a offer because they look great

Will keep them in warm flowing water today so if there is something on them it comes of
 
Many polishing compounds contain binding agents to make them a paste, oxidizers to bleach and surfactants to carry off residue. They can mess with the natural ph of the surfaces between the plates, even after being wiped clean.

That said, non-nacreous pearls might stand up a bit better because they have a lesser degree of protein in content, but I would still suggest some type of neutralizer, such as salt for a finishing treatment.
 
dmj, how about sharing more of the information you have. Any compounds in the paste, how you went about it and virutally anything to help others with natural pearls that need help. Okay we know we need to be careful now but if you could share your secrets it would help many a pearl that may be crying out for it.

Thanks Dave. Okay there are dangers. But we could test the odd damaged natural pearl. Running salt water is easy in a fish tank. Still risks, yes but using a test pearl would be okay if dmj will share more info. Dave, what is the natural pH for saltwater pearls?

Caitlin, dmj hasn't answered you or me yet. Let's hope he does.

Dawn - Bodecia
eBay Seller ID dawncee333 - natural pearl collector and all round pearl lover.
http://shop.ebay.com/dawncee333/m.html
 
It just says diamond paste 50 000 grit that's about it :) haha I will make pictures the moment I can

I'm not really a tester I just do it works Best (for me most of the time) so for today I took some natural untreated salt and made sure the pearls where covered and thats about it to finish the polishing

I think I took away a little layer from the pearl with al my steps not much probable like 0,01 mm

Will update later and with pictures the moment I have the time for it
 
anddd some pics :cool: took me 3 hours before i found out how a camera with no macro is able to make macro pictures

will make some better pictures somewhere 2012 i think :)
 

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Hi Dani?l
I have a tridacna pearl myself, the certificate says it has been polished, in fact it is the back side that has been.
I am curious about the way you took your pictures, curious black light that captures the flame.
Would you tell us about the way you did that?
Thanks
Anna
 
its just a black blackground so nothing fancy there :) for the light i used a ikea led spot

i made the picture very dark and the small led spot makes you see the flame really good

its funny beacause i do have a amazing photo studio at my store only all my naturals etc are at my house so i have to try really hard to make pictures instead of just take them with me the next day and use the pro stuff
 
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ooooh, i missed these photos! just lovely!

so what do most people do with tridacna pearls? i think i've only ever seen them loose and mounted on a ring sort of in a cage. are they difficult to drill to make a pendant? or is it because the flame is on the TOP towards the light? (wouldn't see it on a pendant facing down.......)

- jodie -
 
Nice. Any kind of "working" will reduce the value. Have you tried soaking with mineral oil and then buffing with a soft cloth?
 
Hey Guys

The first natural pearls i ever got where tridacna, i found 6 between 5 and 25 ct in the house of a old indonesian woman who lived in Indonesia somewhere 100 years aggo when indonesia was still dutch kolonial and she took the pearls with here after she moved to holland. Here kids asked me to help getting all the antiques out of the house and if i wanted to have all the gemstones etc

When i first got my eyes on the Pearls i thought it where just old no more luster Pearls. (5 years jewellery school never seen others than culture :s) anyway i took them simply because the old woman had them stored in a verry nice box and al the amazing opals and emeralds she had where just laying around so this had to be something more special.

Now 5 years and a big collection of natural pearls later i was looking at the pearls because there was flame in them only they looked bad and i thought well they are free anyway so Lets try polish them with leather and diamond paste and after that on normal polishing wheel for jewelry now the one i did looks way better has a amazing flame and fine for jewelry

Long story now the question :) I still have 5 to do only im not quit sure if its oke to polish them and if its oke am i doing this the right way or are there better methods ?

Will make pictures of the flames somewhere soon when i have time they just look like any other kima flame tridacna Pearl ;)

Thanks
Dani
Very interesting, I have an old pearl, but dull looking, not shine enough to be a jewelry. any suggestions please.
 
thank you CortezPearls, took a few better closer pictures, please take a look again, it is pearl or not. thank you
 

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Well, the newer photos does give it away as a mother-of-pearl shell button.
It has the portion necessary to get the thread into it for attaching to the item of clothing.
So: Not a Pearl.
What is it? A mother of pearl shell button
 
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