DR. HANNEMAN'S MINERAL COLLECTION WILL BE AVAILABLE FOR SALE IN THE NEAR FUTURE
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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Mon Nov 16, 2020 10:21 pm 
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1bwana1 wrote:
Despite the printing errors G.I.A. is adamant that they don't certify anything, or any one. They issue reports , Diplomas when titles are earned, and Certificates of completion for each component class completed successfully. This is a subtle but significant distinction.

I know it was a mistake, but I operate on a strict "no backsies" policy here :lol:
I agree that doesn't look to be canary tourmaline, just (still nice and uncommon) golden material. I would think it would be defined by color rather than chemical content though.

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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Mon Nov 16, 2020 11:43 pm 
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All my wife's diplomas are from SM campus, I am not sure what they depict as far as this conversation is concerned. Will take a look and see. Back then the classes were all separated. I was going to enroll in the CAD classes several years back, but $$$$$ were tight.

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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Mon Nov 16, 2020 11:44 pm 
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Stephen Challener wrote:
Barbra Voltaire, FGG wrote:
Random neural firing: To begin with, it annoys me when someone refers to a GIA educated gemologist as "certified". The GIA does not "certify" anything. In addition, they do not offer "certificates", they provide identification reports.

Oh really?
Image
They sent a replacement, pictured above and told me to destroy the original but I didn't.

Bad, bad Stephen!


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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Tue Nov 17, 2020 12:15 am 
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A nice video and discussion about the real Canary Tourmalines here:

https://www.gia.edu/gems-gemology/sprin ... lored-gems


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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Tue Nov 17, 2020 4:31 pm 
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Thank you all for the very detailed discussion about certification and issues surrounding such certifications from GIA. Its good to be on a forum where there are experienced individuals who know this craft, unlike me who is just learning. I registered myself on this forum just a few months ago, but its been a good learning experience.

The crux of the argument is: get a certificate! Right. I will, and then share it here. Perhaps I'd give Barbara's recommended labs a try and see what comes up.


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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Tue Nov 17, 2020 4:45 pm 
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Mohmand wrote:
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The crux of the argument is: get a certificate!

No, joking aside reputable labs generally don't give 'certificates' anymore because of legal issues that come along with that language. They issue lab reports giving their best opinion of what's going on with the stone based on the data they collected. I don't know if there are any notable exceptions to this.

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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Tue Nov 17, 2020 10:15 pm 
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Let's start by getting an identification report..........cough cough.
As Stephen said, there are NO reputable labs who issue "certificates".

Also , tourmaline is strongly dichroic. If you are using a laptop give it a spin on a white background. Should show 2 colors easily. Cell phones won't work.
Laptops display with plane polarized light and cell phones use circular polarization.

And, tourmaline is pyroelectric. If you rub the stone with a natural fiber like wool or silk, it will heat and will pick up small ashes or tiny bits of cut paper.

ICA wrote:
As tourmaline cools off, it releases a positive charge at one end and a negative one at the other, which causes it to oscillate. This is known as 'pyro-electricity', derived from the Greek word 'pyr', meaning fire. The Dutch, who were the first to bring tourmaline to Europe, were familiar with this effect a long time before it was given a scientific explanation. They used a heated tourmaline to draw up the ash from their meerschaum pipes, and called the gemstone “aschentrekker.”


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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Wed Nov 18, 2020 1:10 am 
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Also piezoelectric, which was used in depth finders during WWII in subs.


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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Wed Nov 18, 2020 1:29 pm 
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Lab 'report' it is then, not certificate


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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Wed Nov 18, 2020 5:29 pm 
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Mohmand, have you tried giving your stone a spin on the laptop or rubbing it to see if can pick things up?
Report back.


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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Fri Nov 20, 2020 10:16 pm 
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Could you please tell me a little more about this test?

Also , tourmaline is strongly dichroic. If you are using a laptop give it a spin on a white background. Should show 2 colors easily. Cell phones won't work.
Laptops display with plane polarized light and cell phones use circular polarization.


I have what I think is a yellow tourmaline and when I hold it up against laptop screen (looking through the culet), it looks like there are two colors - red on one side and almost a while on the other. Does this make sense? Is this what I should be looking for?

Thank you


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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Thu Nov 26, 2020 8:18 am 
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@Barbara No I haven't done the laptop test b/c I don't have one. Using a desktop. Not sure if the test you mentioned can be performed on desktop. Anyway, I am gonna get a report from the lab you pointed out and share it here. I guess that'll clear up everything.


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 Post subject: Re: Canary tourmaline and Zambian emeralds
PostPosted: Thu Nov 26, 2020 12:20 pm 
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Yes, you can test for pleochroism with a desktop computer. The screen produces plane polarized light. Rotate the stone in front of the screen showing a white page. Rotate it in various different orientations. If it is pleochroic you will see different colors or different shades of the same color in different orientations.


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