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 Post subject: Quantifying Diamond Fluorescence and Its Visual Impact
PostPosted: Thu Dec 16, 2021 7:37 pm 
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A compelling scientific analysis of the many misconceptions we harbor on the effects of fluorescence and diamonds.

Excellent! ⭐️⭐️⭐️⭐️⭐️



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 Post subject: Re: Quantifying Diamond Fluorescence and Its Visual Impact
PostPosted: Fri Jun 10, 2022 10:10 am 
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Hello again,

The compelling nature of this research goes beyond our misconceptions about fluorescence and diamonds. It opens the door for the quantitative measurement of reduced contrast (milkiness) in transparent gems caused by defects in the gem's substance. While cuprian, copper-bearing, Paraiba type, Paraiba-like, and Paraiba do not fluoresce they can have a well-documented glow-like quality that probably comes from defects in my opinion. In the article, the GIA develops both the procedures and equipment to quantify the glow-like properties of relevant tourmaline in my opinion. The glow-like property that some tourmaline possess is extremely important to the visual presence of these tourmalines and their value.

Bruce


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 Post subject: Re: Quantifying Diamond Fluorescence and Its Visual Impact
PostPosted: Fri Jun 10, 2022 11:38 am 
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Excellent points.
Nice hearing from you.


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 Post subject: Re: Quantifying Diamond Fluorescence and Its Visual Impact
PostPosted: Fri Jun 10, 2022 5:34 pm 
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Thank you Barbra. It has been a while. I have been trying to get my new website completed and filled with my writings about tourmaline. It has consumed my energy and I have not reached many people.

I have had problems logging in, but this time it was easy. I wrote again through GO because I now feel very strongly that the labs and the trade have the power to refine the evaluation of Paraiba and its family so the consumer is less exploited. Misinformation and the lack of quality material has lead to the offering of truly pathetic examples of tourmaline as something special.

My goal continues to be, to continue to cut tourmaline as well as I can and bring its beauty to the people. Any help you can render is appreciated. I keep trying to work with the GIA.

Bruce


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 Post subject: Re: Quantifying Diamond Fluorescence and Its Visual Impact
PostPosted: Fri Jun 10, 2022 9:53 pm 
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No kidding. "Paraiba", "Burma", "Ceylon", "Kashmir" are used to describe some of the ugliest stones I've ever seen.


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 Post subject: Re: Quantifying Diamond Fluorescence and Its Visual Impact
PostPosted: Thu May 11, 2023 2:27 am 
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Barbra Voltaire, FGG wrote:
A compelling scientific analysis of the many misconceptions we harbor on the effects of fluorescence and diamonds.

Excellent! ⭐️⭐️⭐️⭐️⭐️


I was studying this subject with an Aussie retired gemologist friend and we were close to publishing what we were writing as findings based on a collection of fluorescent diamonds including some whitish stones. Then this article was published - Yun Luo has done a first class job.
And Gazumped Grant and me.
I hope GIA could decide to do something positive with this research. As Bruce commented - this opens up a new field of study.
But for me it helps confirm that blue fluorescent diamonds that are free of internal graining and clouds are both brighter and appear whiter in almost all good strong lighting environs where color can actually be assessed.


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 Post subject: Re: Quantifying Diamond Fluorescence and Its Visual Impact
PostPosted: Thu May 11, 2023 3:58 pm 
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I am so pleased that other people are seriously interested in the subject of this paper. I contacted the head of the department at the Colorado School of Mines where I am an alumi. The department now does research in both metallurgy and ceramics. I described the paper and felt that similar research on the glow-like quality of some tourmaline (both copper and iron colored) would be extreamly important work.

He replied that it sounded like an interesting project, but all the professors were completely occupied with their own research. I have tried to reach out to gemological laboratories, with no success. I think that the glow-like quality of Paraiba may not just depent on the quantity of copper it contains, but also on the conditions the tourmaline was under when it crystalized

I have most of a 100 cuprian tourmline gems from Mozambique that are ready for testing. This includes some of the best the deposit produced and most of them are unheated. I don't think the future will have such a bounty to invetigate.

PLEASE HELP GET THE WORD OUT.

Bruce


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 Post subject: Re: Quantifying Diamond Fluorescence and Its Visual Impact
PostPosted: Sun May 28, 2023 10:05 pm 
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Bruce Tourm - Love the idea that fluorescence in colored gems can enhance color, as well as reduce color in diamonds with the complimentary effect!
I have researched this topic to death, and last week did a webinar with Branko Dejalin, the Vancouver based scientist who runs a lab there.
Dr. Yun Luo mentioned in her webinar on the first page how prices keep dropping for fluorescent diamonds.
Infact the very first Rapaport discount for DE IF VVS1 was -7% to -10%, and that resulted from a TV expose in Korea in 1993. Dealers and labs were overgrading color of fluorescent diamonds.
Last month the discount for D-F IF-VVS1 was -26%
If anyone wants the full history and some stories I summarized it all here (and BTW I only sell diamonds and jewellery in Australia, so not trying to sell trinkets):
https://www.hollowaydiamonds.com.au/lea ... rescence2/


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 Post subject: Re: Quantifying Diamond Fluorescence and Its Visual Impact
PostPosted: Mon Jun 05, 2023 9:12 pm 
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I (personally) have always preferred to have fluorescent diamonds. Non-fluorescent diamonds are boring to me. (Actually as far as I am concerned, diamonds generally are boring unless they have a strong color or are fluorescent or phosphorescent.) My wife's diamond engagement ring is strongly fluorescent, and I picked it partly because of that.


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