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 Post subject: Gorgeous turquoise I have seen
PostPosted: Sun Sep 08, 2013 4:50 am 
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This is the most beautiful turquoise I have seen,look at the color ,the luster!! What do you think about?Image

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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Sun Sep 08, 2013 11:21 am 
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Spectacularly beautiful. Any idea where it's from?


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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Sun Sep 08, 2013 11:27 am 
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The turquoise appears stabilized to me. Can you get a close up of the side of this material:
Image

And also supply us with the results of some standard gemological tests.....Raman results would be interesting as well.


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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Mon Sep 09, 2013 3:00 am 
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Yes, I have to agree... this doesn't look quite right, compared to all the other turquoise I've cut and seen.

Looks too resinous in luster, and a bit translucent as well. Then again, it's impossible to say anything definitive from a photo :)

-Allan

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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Mon Sep 09, 2013 8:15 am 
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I agree with Barbra and Allan
Most Turquoise as been polymer treated
Some people in the trade estimate that 99 % of Turquose on the market
as been polymer treated :(

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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Mon Sep 09, 2013 9:02 am 
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It is not so easy to determine if a turquoise has been stabilized ; but I have learned the hard way that it is very easy to make sure it hasn't been !
I once bought a very beautiful old turquoise cabochon, supposedly from Iran, which at once I thought untreated (milky blue color, soft luster... very different, less "agressive" than what you usually see).
I had it set on a silver ring with an open back. Meaning, the basis of the cabochon was nearly in contact with my skin.
It was brand new, I wore it ONCE while I was doing my sport (you know, sweating a little bit...).
The morning afterwards, the basis of the cabochon had turned olive green. I had worn it ONCE.
So I thought it was a good but sad confirmation that the stone was untreated. And I barely dare wear it now !
On the other hand, I have another nice big turquoise set as a pendant, open too, the stone in direct contact with my skin. Same kind of blue as that on your picture. I can sweat as much as I want, it is still beautifully blue. But then, in the matrix you can very well, with a loupe, see tiny, shiny bubbles...


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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Mon Sep 09, 2013 11:48 am 
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LOL, thanks Isi for supplying the details of the "sweat" test.

But it won't always work. There are some turquoise stabilization treatments now which are impervious to the sweat test.....actually most of them, now that I think about it. It has been my experience that untreated turquoise often greens up when exposed to oils and sweats.


There is a lot of valuable turquoise information here


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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Mon Sep 09, 2013 1:20 pm 
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While doing my FGA (albiet with a limited number of turquoise samples), the treated stones had a slight translucency on the surface (and maybe 1 mm or so below) that the untreated stones we saw did not.


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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Mon Sep 09, 2013 1:28 pm 
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Exactly Julie; can't positively ID from that pic above, but I'm seeing a little too much translucency on the edges of that specimen. :|


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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Mon Sep 09, 2013 4:44 pm 
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Hi Barbra, yes, that's what I meant. The stone that turned green was untreated and consequently unstable ; the one on the pendant which remains bright blue whatever I do is stabilized through impregnation, and consequently impervious to sweat.


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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Mon Sep 09, 2013 4:52 pm 
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Oh, :oops: yes, that is correct.


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 Post subject: Re: Gorgeous turquoise I have seen
PostPosted: Sun Dec 15, 2013 8:11 pm 
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Nice bit of advertising, tonykun. Well done. Shame you won't come back and tell us if it's treated, or is it even turquoise???


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