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 Post subject: Beryllium or just High Temperature
PostPosted: Tue Aug 22, 2006 4:18 pm 
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The stones pictures were shown to me by a Sri Lankan dealer offering them as unheated padparadscha. I have been seeing quite abit of this type of material coming fm Sri Lankan dealers in the last month and am convinced that this is not Sri Lankan but Beryliumed sapphire imported from Thailand. Im not sure if it would be the rough or finished goods that are imorted.

http://img222.imageshack.us/img222/8919/dsc00898qp7.jpg

The inclusions are testiment of high temperature treatment. Crystal inclusions have melted and are now visible as 'snowball' inclusiosn. The 'halo' surrounding the crystal has also been altered and now displays a regular arranged pattern. In this particulair case the colour suggests Beryllium, but I have seen similair inclusions in sapphires of other colours.

If you look on the GRS websites sinclusion picture library under Heated Sri Lankan (non Be) sapphires there are similair melted crystal inclusions.

So here is what I would like to know. Are these inclusions always indicative of Be heating ? Or are there other high temperature treatments of corundum that do not involve any Be and would have the same affect on the inclusions.


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PostPosted: Tue Aug 22, 2006 5:57 pm 
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Hi Yorick,

That's a good question and it does look a bit suspicious as you pointed out.

I would e-mail your question and photo to Vincent Pardeau at AIGS. He's on the cutting edge of the beryllium treatment question as well as any type of treatments of corundum. He studies inclusions in great detail and should be able to help/diagnose.

Try the contact link on the link below.

http://www.aigslaboratory.com/

Depending on how busy he is, he may just show up here and answer your questions. He visits frequently.


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PostPosted: Wed Aug 23, 2006 7:28 am 
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Hi Yorick,

I can't really get a good look at your picture at the moment as I am restricted to a pretty old computer in an Internet Cafe in Bangkok! I can say though white fluffy cotton wool type inclusions are almost certainly caused by beryllium treatment. This is the effect that the beryllium has on zircon crystals, which are commonly found in Madagascan pink sapphires. These types of pink sapphires are often used to produce the beryllium treated padparadscha type stones.

I can also tell you there are still a lot of these stones floating around the markets here in Thailand and they are pretty cheap to buy.

I have some pictures on my website of inclusions I have found in Be-treated stones and some of these inclusions are very common in these mad-pads. You may be able to compare. The URL is:

http://www.apsara.co.uk/inclusions_mad-pads.htm

P.

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PostPosted: Wed Aug 23, 2006 7:55 am 
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Yup, the pictures on your site are very similair to what I have been seeing. LIke I said they have been coming from Sri Lankan dealers, but I suppose this means little.

Another thing I have been noticeing is that the stones tend to be rather flat, rather than the over deep Sri Lankan sotnes normally seen. Are the rough crystals from Madagascar generally flatter than Ceylon ?


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PostPosted: Sat Aug 26, 2006 3:24 am 
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You are correct - coming from Sri Lankan dealers means very little. One of my clients went into a partnership with some Sri Lankan dealers on a so-called mining venture. He sent me up a parcel of stones from his ‘mine’ to see if I would be interested in them. The parcel was salted with many Be-treated yellow sapphires from Madagascar along with several Songea and other stones. From the style of cutting it was also obvious that most of the stones were cut in Thailand. Virtually every dealer I meet from Sri Lanka claims to have their own mine and from the number who have told me this, if it were true, the entire country would look something like the surface of the moon.

You are also correct in your assumption that Madagascan pink sapphs tend to be shallow. It is pretty rare to find Mad’ pinks with any depth except with small stones.

P.

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PostPosted: Sat Aug 26, 2006 2:38 pm 
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I know that some of the Sri Lankan dealers here go to Madagas to buy rough and polished. The have no qualms telling me that. I heard someone say that 70% of the goods presented by Sri Lankans to be Ceylon is actually Madagas. It is hard to tell seeing that they are both low iron deposits and seem to have very similair inclusions.

I think however that the Madagas Be madpads the Sri Lankan dealer show me are bought in Bangkok. You agree ?


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PostPosted: Sun Aug 27, 2006 3:10 am 
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Perhaps I was being a little harsh! The point I was trying to make is it's better to trust your own initiative. Since the arrival of some of these new treatments in Thailand, a lot of brokers here have caught onto the fact that there is now a higher demand for un-treated goods (and a higher price too), so they now describe many stones as being un-treated, which infact have been treated. It is up to the buyer to decide if the broker is telling the truth.

As to whether the stone you are looking at has been Be-treated or not, from the picture of the inclusion pic (which I've now had a better look at) I'd say it has been Be-treated but this is only from looking at the inclusion picture. Have you tried immersing the stone and checking for an orange colour rim? There is usually one with these mad-pads because they need to keep some pink colour with the orange to make the stone resemble a pad. Also, the white fluffy effect beryllium has on zircon crystals is pretty indicative.

P.

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PostPosted: Fri Sep 08, 2006 8:58 pm 
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The AGTA Lab just announced that all corrundum submitted to the lab that show indications of high/long heat treatment will require advanced testing before Be diffusion can be ruled out. Be has been found in blue sapphire (used to lighten) also. Beware of Padparadsca that shows heating. Great article in Gem Market News, May/June 2006 (from the Guide).


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PostPosted: Sat Sep 09, 2006 7:15 am 
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Hello,
Well what you see on the photo you posted are probably zircon crystals which have been submitted to "very high temperatures". There is an article on this subject on the last gems and gemology which is interesting. You can also see that these inlcusions are similar to the photos 16 I put on the following inclusion gallery about "Beryllium heated sapphires":
Image
see the comple gallery:

http://www.fieldgemology.com/showpic.php?sub_id=44&type=lab

But these inclusion just give you the prove that this stone was heated for a certain amount of time at elevated temperatures but it does not prove that any foreign element like beryllium was added. nevertheless most of the current treatments for this type of stone nowadays involve foreign light elements so you can be suspicious... If you want to know more some further advanced testing like LA-ICP-MS is required. You have also in the last gems and gemology an article on this technique whihc might interest you also.
All the best,

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Vincent Pardieu

www.fieldgemology.org
www.conservationgemology.org

The views expressed here are V. Pardieu’s opinions and do not necessarily reflect those of GIA Laboratory Bangkok (http://www.giathai.net)where he is an employee since Dec 2008.


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