CIBJO releases Gemmological Special Report: considers process of separating measurable facts from opinion; See Gemological Articles below.
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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Wed Jul 10, 2019 9:49 am 
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I agree, all this is quite unsatisfactory.


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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Wed Jul 10, 2019 12:06 pm 
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Blue topaz is pleochroic, sometimes dramatically so. How it looks from the side seems a poor diagnostic in light of that?

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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Wed Jul 10, 2019 12:23 pm 
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I think my friend just wanted to make it clear to me that the "real color" of the stone is far from being as saturated as the picture on the report can let it suppose. And therefore, that we should not deduce from the color only that the stone was probably irradiated. The color seems to be just a (beautiful) trick from the cut.
Of course, they didn't use pleochroism to settle their diagnostic ! :D This is a serious lab.


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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Wed Jul 10, 2019 1:17 pm 
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I think the main point is that, at this time, there is no way to determine if topaz has been irradiated.
The gemologist"s view that we can't make determinations based on color should include an addendum stating that there is actually NO way to positively determine treatment.....

Everyone should send their London Blue topaz to this lab for a report stating "no evidence of treatment".
:roll:

Isi, you should march right back to this lab and straighten them out.


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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Wed Jul 10, 2019 9:08 pm 
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I certainly agree in regards to the colour. That’s why I put the photos up of the rough. Depending on direction of light and view point it changed from light blue to a very intense aqua colour. At no point was it colourless.


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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Thu Jul 11, 2019 12:38 am 
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RockSolidinc wrote:
I certainly agree in regards to the colour. That’s why I put the photos up of the rough. Depending on direction of light and view point it changed from light blue to a very intense aqua colour. At no point was it colourless.


This is a direct contradiction of the Lab's stated logic. Looks bad for this lab in my opinion....


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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Thu Jul 11, 2019 12:44 am 
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1bwana1 wrote:
RockSolidinc wrote:
I certainly agree in regards to the colour. That’s why I put the photos up of the rough. Depending on direction of light and view point it changed from light blue to a very intense aqua colour. At no point was it colourless.


This is a direct contradiction of the Lab's stated logic. Looks bad for this lab in my opinion....


one thing that surprised me as well, is the photos LFG use are VERY different from the photos GRS took. GRS is a lot closer to its true colour, however it may depend on the type of light being used as well.


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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Thu Jul 11, 2019 4:07 am 
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I think I will be able to get more information but not in writing - I will have to wait until I meet my friend in person, which will not be before a few weeks. Be patient ! I won't let the matter down.


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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Thu Jul 11, 2019 9:53 am 
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By the way, there is a point that we haven't discussed so far, we don't know which country the rough was supposed to come from ?


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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Thu Jul 11, 2019 11:08 am 
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Isi wrote:
By the way, there is a point that we haven't discussed so far, we don't know which country the rough was supposed to come from ?


Australia


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 Post subject: Re: GRS report for 'untreated blue topaz'
PostPosted: Thu Jul 11, 2019 12:39 pm 
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Poop. That throws a monkey wrench into the equation.


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