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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Sat Nov 14, 2015 1:21 pm 
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Follow the money. :lol: :cry:


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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Sat Nov 14, 2015 2:13 pm 
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Bill Hanneman wrote:
Follow the money. :lol: :cry:

=D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D> =D>

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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Mon Nov 16, 2015 11:44 pm 
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Sorry friends for replying this topic late. I was out of my city.

Well I have a very important question to ask now as I have consulted some major labs:

For Alexandrite report, it only color change is enough and chromium is optional?

Please kindly provide your input.

Thanks a lot.
Deep


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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Tue Nov 17, 2015 2:46 pm 
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The individual labs make their own decisions and have their own criteria.
Let us know what they tell you. :D


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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Wed Nov 18, 2015 7:33 am 
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yes, Some of the labs need color change + chromium and some labs say that they do not check for chromium if color change is there.(As they assume chromium is there already and its chromium which causing the color change)

Its highly complicated..:)

Thanks


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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Wed Nov 18, 2015 12:54 pm 
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I think it's chromium coupled with vanadium.....at least that is what I was taught.


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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Thu Nov 19, 2015 12:10 pm 
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Barbra here is a color shift chrysoberyl (ugly Alexandrite), i've got it on facebook

Image

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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Thu Nov 19, 2015 12:46 pm 
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Looks like color change to me.


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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Thu Nov 19, 2015 3:06 pm 
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I think part of the problem is the idea of it being "just chrysoberyl." Chrysoberyl is an excellent gem--it has great durability and optical properties, rich coloration and a delightfully marketable name. Why treat it as an ugly consolation prize of a gem? It seems a bit perverse to me to try and cram a stone into a varietal name that doesn't fit (and in the process making promises the stone can't deliver on) when there's a perfectly good one right there.

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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Thu Nov 19, 2015 4:37 pm 
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Stephen Challener wrote:
I think part of the problem is the idea of it being "just chrysoberyl." Chrysoberyl is an excellent gem--it has great durability and optical properties, rich coloration and a delightfully marketable name. Why treat it as an ugly consolation prize of a gem? It seems a bit perverse to me to try and cram a stone into a varietal name that doesn't fit (and in the process making promises the stone can't deliver on) when there's a perfectly good one right there.


THANK YOU SO MUCH !!!!

I love and collect chrysoberyl. An underrated fantastic gem material!!

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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Fri Nov 20, 2015 6:32 am 
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Especially the vanadium chrysoberyls Marlow ! :wink:


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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Fri Nov 20, 2015 12:26 pm 
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Isi wrote:
Especially the vanadium chrysoberyls Marlow ! :wink:


YES!

But you don't see many which have the right bluishgreen color.

But I need def. more!!!

In Munichshow only two - one which a grayish color - interesting but to expensive...

John Bradshaw ( www.rarestone.com ) showed me a nice one - not exactly the color but much better then on the picture - still thinking but empty piggy bank - I bought my first Musgravite and maybe a second one ( a taaffeite but with a suspicious color - light to medium grayish green - worth a Raman check). By the way - the stone has the same kind of inclusions like the iridescent Musgravite Mr. Renfro wrote about in GG this year.
Fine iridescent tubes in the pavillion if you use a stronger LED light. But the stone is very small ( 0,15 ct) .

I will make pics when I get it back.

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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Sat Feb 27, 2016 7:35 am 
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color change chrysoberyl or Alexandrite? (color changes from Brownish Greenish Yellow to Orangy Brown)
GIA categorized it as Alexandrite
Image

GIA Report: http://www.gia.edu/cs/Satellite?pagenam ... 6172549369

better picture: https://myapps.gia.edu/DigitalImageClie ... ortNo=null

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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Sat Feb 27, 2016 1:10 pm 
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We've tried climbing this tree before.
I can certainly see the GIA's point as Nathan Renfro has eloquently presented it in the past.
To paraphrase "The GIA identifies an unknown, they do not make a quality determination. Alexandrite is defined as color changing chrysoberyl"

And yes, a shift from brownish bug juice to yellowish bug juice qualifies as a color change......to the GIA.

:roll:

Do I agree with the criteria, of course not. But it is not up to me. Clearly if a stone of the quality above was discovered in Russia in the 1830's it would have been thrown back where it was found. That is, if anyone even bothered to pick it up in the first place.


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 Post subject: Re: Alexandrite as per AIGS but only Chrysoberyl as per GRS
PostPosted: Sat Feb 27, 2016 1:37 pm 
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Barbra Voltaire wrote:
Clearly if a stone of the quality above was discovered in Russia in the 1830's it would have been thrown back where it was found. That is, if anyone even bothered to pick it up in the first place.

Awwwww, it's a perfectly nice brown chrysoberyl. Just because it isn't an alexandrite doesn't mean the poor thing is worthless. It just means it's overpriced.

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