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 Post subject: A new definition for Parariba tourmaline.
PostPosted: Thu Sep 06, 2018 8:58 pm 
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I am looking at a square Barion cut tourmaline from Afghanistan, that I think has all the qualities of a moderate grade Paraiba. I am tempted to say paraiba type, but then no tourmaline from Afghanistan has ever tested positive for copper so it is correctly named paraiba like. But then terms such as like or type, when the trade advertizes big, clean, moderately toned beauties that could never have come from Paraiba, they don't use such demeaning terms. All the fine work of the gemology laboratories, threw their agreement on the definition of Paraiba, is melting away in the glow of promotion, except for color and composition. The Afghan gem certainly has the color so the mighty pillor of containing copper and manganese is all that is supporting this rare and extremely desirerable "precious" tourmaline. Look at the prices if you don't think it is "precious". It is beyond me why manganese containment is part of the definition of Paraiba since its effect on color is usually eliminated threw heating and purple is not a Paraiba color.

Now for the following questions.

1, If copper always produces a superior tourmaline, why depend on a laboratory analysis to find out what the eye can see?

2, If two tourmalines are identical in appearance, why pay a premium for copper?

3, Is the rarity of Paraiba that important if a nature tourmaline colored by iron can have an identical appearance?

I think the world is justfiably confused about Paraiba and is being exploited. To reduce the amount of exploitation I think tthat the definition of Paraiba should be modified. It should drop the "chemical" part of the definition and let the eye determine what is Paraiba. I think there is support for this in the inclusion of vanadium in both chrome tourmaline and emerald as the major chromophore, in some gems, rather than chromium. But then green beryl colored by iron is just green beryl. I don't think the last definition is bad because any emerald that matches a green beryl should not be called an emerald. Oh and how about sapphire, that has been called upon to carry all the colors of the rainbow, except red, because the old names caused confusion? Is red emerald on the horizen? Exploiting names?

The inclusion of a chemical part in the defintion of Paraiba has certainly not hurt the gemological laboratories bottom line. The lust for rarity has even extended to provenace and valuations that can not be supported by the eye. I even think that the pricing of Paraiba has been distorted by size. It is completely unrealistic to find a clean 5 carat gem that came from Paraiba Brazil, but an included 1 carat could certainly be from the original location. So the reprocussion of testing for copper go on.

Finally the identification of tourmaline is trivial since no sythetic material is on the market and its gemological properties are not closely matched by any other gemstone. With elimination of the chemical part of the definition and provenace we could have a transparent market where the beauty of the tourmaline is dominant not a report.

Bruce


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Thu Sep 06, 2018 9:14 pm 
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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Thu Sep 06, 2018 10:15 pm 
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Interesting take, Bruce. Thanks for sharing your thoughts.

bruce_tourm wrote:
It should drop the "chemical" part of the definition and let the eye determine what is Paraiba.


It wouldn't solve the issue imo. Besides the fact that people see colors differently. You would just run into another problem: "where do we draw the line?"
The top material would pass with flying color, but there would still be a lot of borderline cases; Paraiba for some, not-Paraiba for others.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Thu Sep 06, 2018 10:49 pm 
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The problem of marginal material and differnces between perception and opinion is endemic to the world of gemstones. With the change in definition I propose, at least the debate would be done over what can be seen, not something you need a report for. In my personal world, I can see the effects of copper on the absortion of light in tourmaline with my spectrometer that I can not see with my old eyes. Trace amounts of copper in tourmaline is not that rare so if laser ablation detects it, is it cuprian? I don't think so. So at what level of copper does a tourmaline become cuprian? I think copper becomes a factor in the chemical part of the present definition when a spectrometer can detect it, but that would not be in the new definition. I believe the GIA uses a spectrometer to test for copper and a rather abitrary level of absorption to concluded that the level of copper absorption is significant.

Bruce


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Sun Sep 09, 2018 12:41 pm 
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bruce_tourm wrote:
I am looking at a square Barion cut tourmaline from Afghanistan, that I think has all the qualities of a moderate grade Paraiba. I am tempted to say paraiba type, but then no tourmaline from Afghanistan has ever tested positive for copper so it is correctly named paraiba like. But then terms such as like or type, when the trade advertizes big, clean, moderately toned beauties that could never have come from Paraiba, they don't use such demeaning terms. All the fine work of the gemology laboratories, threw their agreement on the definition of Paraiba, is melting away in the glow of promotion, except for color and composition. The Afghan gem certainly has the color so the mighty pillor of containing copper and manganese is all that is supporting this rare and extremely desirerable "precious" tourmaline. Look at the prices if you don't think it is "precious". It is beyond me why manganese containment is part of the definition of Paraiba since its effect on color is usually eliminated threw heating and purple is not a Paraiba color. I

Now for the following questions.

1, If copper always produces a superior tourmaline, why depend on a laboratory analysis to find out what the eye can see?

2, If two tourmalines are identical in appearance, why pay a premium for copper?

3, Is the rarity of Paraiba that important if a nature tourmaline colored by iron can have an identical appearance?

I think the world is justfiably confused about Paraiba and is being exploited. To reduce the amount of exploitation I think tthat the definition of Paraiba should be modified. It should drop the "chemical" part of the definition and let the eye determine what is Paraiba. I think there is support for this in the inclusion of vanadium in both chrome tourmaline and emerald as the major chromophore, in some gems, rather than chromium. But then green beryl colored by iron is just green beryl. I don't think the last definition is bad because any emerald that matches a green beryl should not be called an emerald. Oh and how about sapphire, that has been called upon to carry all the colors of the rainbow, except red, because the old names caused confusion? Is red emerald on the horizen? Exploiting names?

The inclusion of a chemical part in the defintion of Paraiba has certainly not hurt the gemological laboratories bottom line. The lust for rarity has even extended to provenace and valuations that can not be supported by the eye. I even think that the pricing of Paraiba has been distorted by size. It is completely unrealistic to find a clean 5 carat gem that came from Paraiba Brazil, but an included 1 carat could certainly be from the original location. So the reprocussion of testing for copper go on.

Finally the identification of tourmaline is trivial since no sythetic material is on the market and its gemological properties are not closely matched by any other gemstone. With elimination of the chemical part of the definition and provenace we could have a transparent market where the beauty of the tourmaline is dominant not a report.

Bruce

I agree Bruce. The finest blue toumaline I have ever seen was a non- cuprian stone.
I passed on a Lembeck/ DeCristoforo stone about 12 years ago because I thought $500/ct. was too much for a non- copper stone. Looking back I now realize that it was a great deal for a stone of that quality. We have recently seen that trace amounts of chromium in an ugly dark green toumaline only makes for an ugly chrome tourmaline. All the wild appraisals in the world isn't going to change the fact that it's worth 10 bucks/ct. max. I see all the Sri Lanka dark blue spinels marketed as cobalt spinels due to their microscopic trace of cobalt. I'm sure it's to make people think that this is just like the Vietnam material. How about Rubellite? I have purchased much toumaline from many dealers that use the name Rubellite for stones that range from pure pink to purple. Out of all, this is the only one I consider Rubellite.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Mon Sep 10, 2018 12:47 pm 
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Well Nick, you hit me in a soft spot when it comes to Rubellite.

I had a long running debate with my younger daughter, when she was in high school, about yellow and red tourmaline. It was her eyes against mine on how much green or purple we saw in the tourmaline. Well I just finished a little beauty that was going to prove tourmaline could be red. But by the time I got to see her, the sky had turned gray and the stone was purple, not the red, that I saw under my incandescent work light. I finally did get a pure enough yellow, but its tone level was pastel. I was also able to get a very interesting tourmaline that is both medium toned and red. It is a bi-color that is half colorless and half red. I made a round out of it with the crown being red and pavilion being colorless. Together they snap.

Tourmaline has such dynamic color that I think you really need to live with the gems to fully appreciate them. With tourmaline I see stones that go from blue to green and red to orange under the appropriate lights, but look just like stable blue greens and orange reds under the normal mixed light we modern people live with. The beauty and value of these will be debated, but it should depend on what we see, not on chemistry.

Finally Namibian blues are my favorite and when they not too dark, they rate right up there with the best colors in tourmaline. And they are not common either.

Bruce


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Fri Sep 14, 2018 2:42 pm 
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Could not agree more, Bruce!

But...same thing goes for Ruby, Emerald, Pads, Blue Sapphire, & Australian Opal. While they all share the same chemical qualities, more or less, it is providence that dictates price. I specialize in selling Welo Opal. I cherry pick the best ones, they blow away most Aussie material, yet inferior Aussie stones are 5 to 10 times the price.

The only thing that separates Paraiba from the pack, is Copper. Of course, top quality stones are outstanding, but I've seen many Afghanistan stones that were equal to medium & lower Cuprian quality, at 10% of the price, & much cleaner. Not to mention, untreated. But providence does play a part too. Brazilian stones are always more expensive than Nigerian or Mozambique stones.

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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Thu Sep 20, 2018 8:29 am 
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I visited a high end deal a couple of times with my spectrometer. I showed my collection without any intention of selling him anything. Though he did give me an offer on one of my high quality sea foam tourmalines from Afghanistan that was so low I could not get the rough for that price. My reward was seeing and testing his unheated highly included pieces of high quality unheated Brazilian Paraiba. (they were from the original find) I don't think my absorption graphs were very high quality because of the specimens being rough and included, but I got to see their color in person. The only gems he wanted test was his collection of clean bright neon blue green tourmaline of good size from Afghanistan. They were beautiful, but they did not have a trace of copper. And they were probably not heated. ( His customers kept pushing him to have the collection test because it must have copper to be so beautiful) The Paraiba was rather drab, but I am sure it had potiental if it did not fall apart with heating. It was bluer than my purples from Mozambique and I am always interested in new twists in the tourmaline color world.

This experience reinforces my strong feelings that you have to have a close personal relationship with a great colored stone to truely appreciate its exceptional qualities. They will never be descibed or phtographed adequately. Slight changes in color with lighting and our personal perception of properies such Paraiba's glow like qualities, can make such a difference in value and beauty. But if you can just keep the discussion on provenience and chemistry, your prices are easier to support with a certified "expert" opinion . I was once asked by a jeweller, what "interesting" things he could say about tourmaline to sell it! Let them see its beauty by having it in the store and not just on memo is my expert opinion. I was once dragged to a high powered store, one of a large chain, that claimed that they had everything in gems. They did not have a single tourmaline. Amazing! They did have a large case of blue sapphires that had both natural and synthetic sapphires mixed together!

If you want to share my attempt to bring the beauty of tourmaline to the world visit my site BruceFryTourmaline.com. You might find it a first step in appreciating a wonderful gemstone that still does not get the respect it deserves.

Bruce


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Thu Sep 20, 2018 9:09 am 
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Missed this big Brazilian Paraiba specimen. Sold for 1200 bucks.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Fri Sep 21, 2018 3:09 pm 
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Nicky Newark wrote:
Missed this big Brazilian Paraiba specimen. Sold for 1200 bucks.


$1200 dollars??? Whaaat....
That materials going for that much these days? If you guys remember that's the exact same type of stuff I used to sell a lot of...roughly 7-10 years ago. It's been so long I can't remember exactly what prices were back then, but I can tell you I would have paid nowhere near that.....just from looking at your one picture posted.
Wow

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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Fri Sep 21, 2018 3:59 pm 
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Great post, Bruce! If you know me you know I touted those exact same points for years now..... across numerous forums and social media websites.
Almost verbatim....
I've been trying to drill it into people's minds and making it known, just how ridiculous it is the prices people are paying for cuprian tourmaline...... when it looks nothing like the embodiment of what a Paraiba should be.
my saying I always use is...."color is king"..... couldn't be more true in this case. The elemental makeup means squat, when it doesn't correspond to a special attribute of its color. If this were not the case, then other unique end members would be just as popular in this pricey. This is not the case though, because it was the color that originally gave people pause, and it was the color that cemented these tourmaline in the annals of History.
Like I have always said, if it doesn't have a vivid hue, then it's not a Paraiba tourmaline. This is reflected in the quantity of copper inside Brazilian and Mozambique Cuprian tourmaline. The highest levels ever tested are found in Mozambique, yet they don't correspond to a color of similar stature. If we based prices on how little or how much copper is in each Stone, then Mozambique would win every time. This is not the case though. Somewhere in an older write-up I did, I cited numerous articles and Publications showing copper having been found in numerous tourmaline crystals.. as far back as 1930. This was in a handful of different localities, I was able to discover. So copper is nothing new when it's found in tourmaline, but what is new, is the combination of everything coming together and turning out a color that seems to defy nature and mesmerized The Mind's Eye.

By default, a paraiba that is considered Neon, or has a "glow", must inherently be Vivid in saturation. If you're cuprian tourmaline is not vivid, then it is not a paraiba tourmaline, in my opinion.

There's also something I've always wanted to touch on and have a little here in a little there, regarding the colors of turquoise, cyan, or similar hue, possibly having some different perspective-based property associated with them.
for some reason people see more of what they deem to be a "glow" in stones of these colors. I see it in Turquoise myself, and have always been drawn to colors of a similar nature. Turquoise just looks like it's a glowy color to me in general. Why do I think this? Why have I and so many others been drawn to that "strong" color of blue/blue-green?
Just why are so many people obsessed with the same hues, and oftentimes they
perceive a level of vibrancy, in their eye, that may not actually exist at all. Is that a misunderstanding of the aspect of copper and what it does to a stone's color, so they see what they believe?
Do they assume something special happens with copper and it automatically imparts a glow.... just due to the simple fact that the tourmaline has copper..... or are they actually seeing something tangible and that which exist...even in stones with low to medium saturation levels?

I have often wondered if the cracks and Tiny inclusions in some lower saturared paraiba, still possibly have some type of glow due to the multitude of tiny fractures scattering the light? Akin to something such as the old school red Mahenge spinels, with there tiny bubble-like inclusions. They lacked Extinction because of it and picked up a soft glow like look, as well.

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Last edited by Jason Barrett on Fri Sep 21, 2018 8:25 pm, edited 1 time in total.

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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Fri Sep 21, 2018 4:05 pm 
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Lighter toned emeralds often do the 'glowey' thing for me. They might lean a bit lighter and a bit bluer than 'ideal' but man do they do it. Top grade gem silica too, though it sort of cheats with the translucency letting it more literally glow.

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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Fri Sep 21, 2018 11:05 pm 
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With a thanks to Jason for motivation, I will try and list my observations, thoughts and aquired facts about Paraiba/paraiba/african paraiba, cuprian, paraiba like., paraiba try tourmaline. They are not in any particular order.

1, No one knows the optimal level of copper in tourmaline to produce the glow like property seen in high quality blue green/cyan coloed tourmaline.

2, The heating of tourmaline with a copper as a chromophore does more than reduce Maganese+3 to Manganese +2, which removes the red vector in some copper affected tourmaline.

3, Excess heating can effect the expresion of the copper +2 chromophore and render the tourmaline less vivid/washed out.

4, Even some of the best grades of Paraiba had a touch of gray that had to be heated out.

5, Iron is not a factor in the coloration of most cuprian tourmaline.

6, The glow like property of Paraiba etc. is restricted to the cyan and blue green part of the color wheel.

7, Copper can effect the visual presentation of tourmaline in many colors. Not all cuprian tourmaline will appear bright when cut, but if the tourmaline is particularly bright the chances that it has a copper chromophore is significantly increased.

8, Tourmalines with a medium tone level and a saturated color show the best glow like features.

9, Copper colored tourmaline generally does not show a strong dichroic nature.

10, Some greens will heat to a bluer gem and others will not. I believe that the heatable greens gain their yellow color vector from radiation induced color centers and the refractory greens are effected by low levels of iron.

11, Copper +2 can not inpart both a blue/cyan color vector and a green vector, no matter how the concentration of copper chromophore varies.

12, The eye/mind has evolved over millions of years to maintain color consistency under natural light that varies during the day. Part of the refindment is assumtions about the level of light that should be return to the eye/mind from a certain amount of illumination on an object. If the eye/mind gets back more light than expected, the eye/mind is fooled into thinking that the surface is producing light. That sensation of producing light is what can be called glow-like.

13, I think only tourmaline in the cyan.bluegreen color zones can fool the eye/mind enough to appear to produce light under the proper conditions.

14. The glow-like property of tourmaline is best seen under moderate to lower levels of illumination.

15, No one can determine whether a tourmaline has been heated or not. Even a purple cast will not suffice to certify that the tourmaline is unheated.

16, For a more complete effort on descibing beautiful tourmaline and my research efforts on especially color change, another example of fooling the eye/mind, visit my website at BruceFryTourmaline.com.

Bruce

I like to think of tourmaline as the jester of gemstones because with its complexity and numerous colors, tourmaline fools a lot of people. Close personal observation and knowledge is need to be sure that the tourmaline you want to buy measures up. The gemology labs give you very little support in producing a certification for tourmaline.


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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Sun Sep 23, 2018 12:47 am 
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Awesome come back, Bruce! Well covered and well said.
I don't have time right now, but sometime later I would like to touch base on a few of the points and observation you said in the last post.

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 Post subject: Re: A new definition for Parariba tourmaline.
PostPosted: Sun Sep 23, 2018 5:25 am 
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I look forward to what you have to say. Tourmaline's color and its presentation is a wonderful part of the beauty of gemstones.

Bruce


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