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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Tue Jun 15, 2010 2:20 pm 
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That's a typical color change (and not color shift) in natural sapphire. As Alberto said, nothing conclusive about that.

Oli.

tudortwo wrote:
This is probably a dumb question, but do be-treated stones have a very distinctive shift in color. My sapphire goes to a very violet color in incandescent light. It's more blue in natural light. Or is even something like this inconclusive?


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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Tue Jun 15, 2010 3:04 pm 
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Confused by your answers gentlemen. I just want to know, do Be-treated sapphires have the ability to color change, or not, or no one knows for sure? Please take pity on me since I did ask a dumb question and I need a simple answer. :oops:


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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Tue Jun 15, 2010 3:08 pm 
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I've wondered about this too. A color shifting BE treated stone would not surprise me but a profound cc would.

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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Tue Jun 15, 2010 3:43 pm 
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tudortwo wrote:
Confused by your answers gentlemen. I just want to know, do Be-treated sapphires have the ability to color change, or not, or no one knows for sure? Please take pity on me since I did ask a dumb question and I need a simple answer. :oops:


Ok, try to recap:

question: have you ever seen a CC be-treated sapphire?
Answer: no, but i didn't searched for one

question: do you think a be-treated sapphire can be CC?
Answer: yeah, why not?

ciao
alberto

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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Tue Jun 15, 2010 5:52 pm 
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:lol:
Yeah not an easy one. I think the treatment could "improve" pleochroism in a stone (OK that's not color change), but not sure Be treatment would create a color change stone who doesn't have any premise.

Never heard about it till now.

Best regards

Oli.


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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Wed Jun 16, 2010 7:55 am 
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I asked Richard Hughes, and he said he never heard of beryllium causing a color change gem.

Well, just wanted to thank everyone again for all your thoughts on this subject, and I hope the AIGS and other labs post what treatments they can test for on their websites.


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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Wed Jun 16, 2010 9:16 am 
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How are they testing for it?
Can you find out for us?
Thanks.

Update.
I went to their site in Bangkok and it appears the determination is made microscopically. Please correct me if I am incorrect here, as I think the sophistication of light element diffusion has, in many (most) cases, has made microscopic determination somewhat obsolete.
Direct Link= http://www.gemresearch.ch/news/RepNewTr ... reat-E.htm


Yes Barbara give me few days I'll find out.This is Important for me. Because....

One of my friend B/S returned from US as Be treated with a cert from GIA. Second opinion from GRS state same. I saw copy of GIA cert. I check that stone under microscope only Straight colour bands visible no any other inclusions.
I thought in this case they determined by LIBS or LA-ICP-MS. because no inclusions and BS don't show any rim

But owner of the stone 1000% sure this one not Be treated. this is long story will be continue....


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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Wed Jun 16, 2010 1:26 pm 
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tudortwo wrote:
I asked Richard Hughes, and he said he never heard of beryllium causing a color change gem.


Good to know!

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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Wed Jun 16, 2010 2:48 pm 
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It's logical Be on its own would not CAUSE a color change, but the question, as I understood it, was can a Be treated sapphire display a color change.

I don't see why not, if there was sufficient chromium and vanadium present in the gem to begin with.......right?


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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Wed Jun 16, 2010 9:37 pm 
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Thank you Barbra - I was thinking the same thing. (Not that I know anything..." I know nothing "- Sgt. Schultz)

Tudor - Are you asking can Be treatment interfere with color change? Can Be treatment cause color change?

My 2.5 cents...or something less....

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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Wed Jun 16, 2010 9:45 pm 
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I was simply wanting to know if a color change sapphire would not be able to be a diffused stone. I just wanted to see if I could rule it out other ways to determine a non diffused stone other than LIBS or other very sophisticated equipment, but I know that is like pulling a rabbit out of thin air. :cry: Thanks. :)


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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Thu Jun 17, 2010 11:19 pm 
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One of my friend B/S returned from US as Be treated with a cert from GIA. Second opinion from GRS state same. I saw copy of GIA cert. I check that stone under microscope only Straight colour bands visible no any other inclusions.
I thought in this case they determined by LIBS or LA-ICP-MS. because no inclusions and BS don't show any rim

But owner of the stone 1000% sure this one not Be treated. this is long story will be continue....


I will continue my story. When they got this Blue sapphire from GIA someone suggest them even if they polish a stone in the same lap where Be treated stone polished there is lot of possibility this stone show as Be treated.

So the owner of the stone did little re-polish whole stone around 0.30 cts. wastage. He has send the stone again to GRS. GRS told no Be treated this time.
In this process its cost them around $400 only for certification of around 5 cts. Blue sapphire. (03 certificates)


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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Fri Jul 16, 2010 12:35 am 
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Dear all,

For information:
At the GIA labs in New York, Carlsbad and Bangkok we test all treated rubies and sapphires with LA-ICP-MS, it is a routine test. We don't use LIBS. Here is a link to the instruments used in the lab for both research and customer services:
http://www.giathai.net/lab_instruments_VP03.php

Regarding AIGS, when I was the lab director from 2004 to 2006, when there was a suspicious stone, we were sending the stone to be tested with LA-ICP-MS at GIA Lab Bangkok as we were then collaborating with GIA Lab Bangkok and the University of Pau in France on research project regarding Be in blue sapphires.
LA-ICP-MS was then (and I think is still) an instrument far too expensive to acquire (and also to run...) for labs of the size of AIGS (and smaller) as my calculations told me then that it would not have been possible to get a return on the investment even if AIGS was increasing by 100% its prices for identification reports and if we had as a result of that acquisition an increase in business. As it was said before universities commonly ask for several hundred dollars for LA-ICP-MS testing and they are not really making money at these prices.

To my knowledge in Bangkok currently only the GIA Lab Bangkok and the GIT have their own LA-ICP-MS at the lab and use it not only for research but also to provide identification services for their customers.

Please just stop believing that a lab asking $30 for a report will provide you the same service as a lab asking $300 for a report. I don't mean that labs providing you reports at $30 are offering bad services, in many cases they are doing a very good job but each lab has its own limitations. You see I've worked at AIGS, Gubelin and now at GIA Lab Bangkok, in all cases I was feeling that we were offering excellent services to our customers, but between a lab providing services at $30 and another providing services at $300, the thing is that the staff, the instruments, the lab procedures, the research are just not at the same level and thus the cost for the reports is not the same.

Hoping that this was helpful.

All the best,

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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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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Fri Jul 16, 2010 11:57 am 
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Thank you Vincent for taking the time to chime into this thread. Supposedly GIT has one of those expensive machines, and they can test for diffusion. I believe they offer that service on their gem brief. Please correct me if I'm wrong.


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 Post subject: Re: AIGS ability to test for diffused corundum
PostPosted: Fri Jul 16, 2010 12:32 pm 
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vincent pardieu wrote:
To my knowledge in Bangkok currently only the GIA Lab Bangkok and the GIT have their own LA-ICP-MS at the lab and use it not only for research but also to provide identification services for their customers.



Hey Marsha. I think this is what you're looking for?

J-

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