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 Post subject: Re: Share something rare
PostPosted: Wed Aug 25, 2021 10:42 am 
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How about rare Congo Andesine? Sorry couldn't help myself


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 Post subject: Re: Share something rare
PostPosted: Wed Aug 25, 2021 12:15 pm 
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Nick, I am not sure I am following along. Is it that the profile pic is a rare red feldspar?

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 Post subject: Re: Share something rare
PostPosted: Wed Aug 25, 2021 12:56 pm 
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LOL. I get it. Is Gem France still selling this stuff as naturally occurring Congolian (not 100% sure that's a word) feldspar?


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 Post subject: Re: Share something rare
PostPosted: Wed Aug 25, 2021 2:19 pm 
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Barbra Voltaire, FGG wrote:
LOL. I get it. Is Gem France still selling this stuff as naturally occurring Congolian (not 100% sure that's a word) feldspar?

Thank you I wasn't.
[http://www.rocksandgems.info/gemstone_properties/properties_feldspar.shtml]

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 Post subject: Re: Share something rare
PostPosted: Wed Aug 25, 2021 3:23 pm 
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I guess the better question would be, does he sell any.


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 Post subject: Re: Share something rare
PostPosted: Wed Aug 25, 2021 6:37 pm 
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In any way in relation or of a similar related event that was going on back then, to this article I read quite awhile back before joining here. So this currently is something that dates back a ways I assume.
http://www.jewelcutter.com/articles/andesine_scam.htm

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 Post subject: Re: Share something rare
PostPosted: Wed Aug 25, 2021 6:58 pm 
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Same overall deal, but I think we still don't have the complete, complete picture (aside from a few basic facts like there categorically being no find of red andesine in The Congo). I'm still confused about things like the findings in Tibet, and it doesn't help that there are those who continue to work hard to confuse the issue to this day.

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 Post subject: Re: Share something rare
PostPosted: Thu Aug 26, 2021 12:24 am 
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George Rossman got to the bottom of this several years ago.
Look for his reports on it.


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 Post subject: Re: Share something rare
PostPosted: Thu Aug 26, 2021 12:01 pm 
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Barbra Voltaire, FGG wrote:
LOL. I get it. Is Gem France still selling this stuff as naturally occurring Congolian (not 100% sure that's a word) feldspar?

Yep , they are still selling it. I was just being a wise guy. We beat the Andesine scam to death a few years a go. Looks like he isn't much more honest with his other material.


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 Post subject: Re: Share something rare
PostPosted: Thu Aug 26, 2021 4:39 pm 
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Barbra Voltaire, FGG wrote:
George Rossman got to the bottom of this several years ago.
Look for his reports on it.

I need ti reread thi stuff. Didn't Rossman visit the Tibetan mine at some point? I generally consider him trustworthy, and certainly moreso than some people involving themselves in this matter. But it's still odd to me that the tibetan samples weren't geochemically distinct from known treated material if I remember right, which makes some of this harder to unspool. Perhaps just an unfortunate coincidence, but one wonders if any of that Tibetan material ever hit the market as well.
Edit: rereading I guess they're a bit distinct, just more close than some other finds. That makes it easier then.
Some people are guaranteed to make wild accusations on anything related to this of course--just see some responses to thr GIA's testing of the newer Ethiopian material (which is geochemically distinct from other finds and IMO obviously natural material, distinct in the hand too).

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 Post subject: Re: Share something rare
PostPosted: Thu Aug 26, 2021 5:52 pm 
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As I recall, the Tibetan mine proved to be salted.
Dr. Rossman and I corresponded well over a year concerning this feldspar. I ended up going to a seminar he hosted at CalTech on the subject.

At the time it was determined (by Dr. Rossman) that the only red feldspar, which had not been subjected to treatment was from Oregon.


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 Post subject: Re: Share something rare
PostPosted: Thu Aug 26, 2021 6:19 pm 
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Yes Rossman did visit the Tibetan mine. No one visited the Congo(democratic republic) mine because it does not exist. Kinda pricey for something that's worthless. I should know, I have 4 of them :D


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 Post subject: Re: Share something rare
PostPosted: Thu Aug 26, 2021 6:38 pm 
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LOL, I have a couple too. But I was lucky, Bear Williams gave them to me as a gag gift.


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 Post subject: Re: Share something rare
PostPosted: Thu Aug 26, 2021 6:47 pm 
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So are the AIGS certs authenticate? or what are the thoughts on this lab in Thailand.

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 Post subject: Re: Share something rare
PostPosted: Thu Aug 26, 2021 6:59 pm 
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Many labs issued reports on these stones indicating natural, no evidence of treatment. AGTA was probably at the top of the list.
It was a clear example of "You don't know what you don't know."

That is why most lab reports today will be filled with legalese on the reverse side of the identification indicating that the findings are essentially an educated opinion within the limits of current knowledge and instrumentation.

From 2009, peer reviewed.
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