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 Post subject: Purple tourmalines
PostPosted: Fri Jun 08, 2018 4:09 pm 
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Hey everyone! I have a few purple tourmalines that I sent off to AGL to get tested for copper, and I called them today and she said based on the shade of purple, they aren’t even going to test them. I know AGL is probably the most respected colored gem lab but I just wanted to double check with you guys before they send them back to me. Do you think I should get them checked regardless, or do you agree with AGL? I didn’t know you could determine copper just from looking at the purple color! Hopefully Bruce can chime in :D


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 Post subject: Re: Purple tourmalines
PostPosted: Fri Jun 08, 2018 6:52 pm 
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What reason did they give you for not testing them?
"Color" doesn't sound like something I would expect Christopher Smith to say.


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 Post subject: Re: Purple tourmalines
PostPosted: Fri Jun 08, 2018 7:17 pm 
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They wouldn't get the "Paraiba-like" denomination on the lab report because the color doesn't fit their color criteria; maybe that's what they meant?

You can always ask again and have them test for the presence of copper in your stones. At least get a verbal confirmation. If that's what you really want to know.


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 Post subject: Re: Purple tourmalines
PostPosted: Fri Jun 08, 2018 7:56 pm 
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Barbra, yes I thought it was a bit weird too. It wasn’t Christopher I was talking to, it was a lady, and I could hear her talking to another woman in the background. She just simply said this color would not have copper in it, because it is on the pink/purple side rather than the blue/purple side. In any case I did call back and request that they be tested anyways. Aren’t there cases of these kind of colors with copper? The stones are pinkish purple, but still definitely purple dominant! I thought there were even pink copper bearing ones sometimes? I could have misread though, it’s very possible!


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 Post subject: Re: Purple tourmalines
PostPosted: Sat Jun 09, 2018 12:27 am 
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I would agree they look like traditional iron/manganese purples rather than copper/manganese purples. But I would test them anyway, since as you say there is a wide range of possible colors with copper in.

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 Post subject: Re: Purple tourmalines
PostPosted: Sun Jul 01, 2018 5:59 am 
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Sorry for not chiming in earlier, but between a fractured email that erases my emails at times and chrome on my mind rather than chromium for a hard question on what colors ruby, I haven't been emailing much. I hope to have it fixed soon.

YOU CAN NOT DETERMINE COPPER CONTENT BY COLOR ALONE PERIOD.

To get a qualitative determination of copper content with a specrometer like mine is simple, straight forward and should be a very low cost screening. I have problems with testing pink to red tourmaline for copper only because my instrument does not extend far enough into the infrared to see the complete second copper peak and high manganese makes the absorption graph more complicated.

This being said, when I sent a red purple into the GIA as a test, they do not test that color for copper unless asked to. There was no added cost. The only defense I can give for the policy of not testing tourmaline of many colors, outside of Paraiba's range, is that tourmaline with a significant copper content is very rare in the world.

Now what is a "significant" amount of copper. Copper has to be a chromophore at the concentration in the stone. But the level of copper that affects the stones color varies with the concentration of other chromophores such as manganese, so it is hard to put a number to that magical level where the tourmaline should be called cuprian, in my opinion.

I believe that the GIA uses some rather arbitrary absorption level for copper, for their work.

Finally, I would not expect red/pink/purples to heat to interesting colors even if they contained copper, because their level of copper is probably pretty low.

I would be happy to test any tourmaline for copper for the cost of shipping. I have found many tourmaline in my collection to contain copper, that I did not buy as cuprian.

Bruce


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 Post subject: Re: Purple tourmalines
PostPosted: Tue Jul 10, 2018 7:28 am 
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U should enjoy ur purple tourmalines for what they are, dont worry about copper content! I just had a purple tourmaline pend appr & the retail value is over $25,000.00 for the pendent. mine is only 3 stones in 14kt yellow gold, a treat to wear & something one will not see on the street most likely-enjoy ur stones-steve...


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 Post subject: Re: Purple tourmalines
PostPosted: Tue Jul 10, 2018 8:44 pm 
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I agree. I have an oval purple tourmaline and the chromophore(s) responsible for the color is not copper. Still gorgeous. Wouldn't be more gorgeous with a copper content. :|


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 Post subject: Re: Purple tourmalines
PostPosted: Wed Jul 11, 2018 7:14 am 
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Very interesting. Would you know where the purple tourmaline came from? I have some small examples from Madagascar that are purple, but have a different shade than my cpper tourmaline gems from Mozambique. I see no reason why manganese and iron can not produce purples, I see exactly the same cyan hue in both iron based and copper based tourmalines.

As I have said before, I think the use of both a chemistry based definition for Paraiba/ paraiba type and paraiba like tourmaline was not a good decision. Neither was the use of a place name for a variety of tourmaline that by the nature/complexity of tourmaline would NOT end up being a unique location for that hue/chemistry in tourmaline. I think that high quality cuprian tourmaline can stand on its brightness and glow like qualities when compared with iron based tourmaline, but not all copper based tourmaline are like the high quality material.

Finally I think anyone lucky enough to have a quality purple tourmaline should treasure its rare beauty, but having copper or not does effect its value and its abilty to be increased in value by heating. I personally am not a heater. Blue purples are the rarest of hues in my world of tourmaline.

Bruce


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 Post subject: Re: Purple tourmalines
PostPosted: Wed Jul 11, 2018 12:08 pm 
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Bruce, if u are referring to the 3 stone pendent, i can only tell u what is on the invoice with each stone, top & center are listed as Mozambique, bottom stone is Brazilian. Total cost to me was less than $1200.00/3 stones. Clairity listed as VS1, total cts, 23.14cts-steve...


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 Post subject: Re: Purple tourmalines
PostPosted: Tue Jul 31, 2018 11:05 am 
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I used to be a small collector of purple(and associated purple hues) tourmalines, many years ago. Richard Wise got me onto 'em, especially after learning how rare and unique that color was, even for tourmaline.

Hey "Ruby302", regarding those purple cuprian tourmalines you postedno above, can you show either the lab report with its origin determination, and/or some type of tangible proof that they are copper bearing?
if I remember correctly, you used to buy the majority of your stones off eBay, and then never send any to have a lab report done! You always trusted that "appraiser" of yours, to tell you everything about every stone you sent him, regardless of his level of expertise on said stone. I hope you broke away from that "sphere of bad influence" he had become. Those appraisals he gave you on each stone you sent him, which at one time seemed like half of all gem species, happen to be waaaay overvalued and not practical in the least. I hope you found someone new to value your online gem purchases, because that other guy was just pandering to you, your pride, and your ego.


How do you even know what you have is real, regarding these purple "cuprian" tourmalines?

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 Post subject: Re: Purple tourmalines
PostPosted: Wed Aug 01, 2018 5:01 am 
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jason :twisted: someone should staple ur tongue, read before u write, i never said these were cuprian tourmalines, i stated they were bought on ebay, listed as purple tourmalines with the stated origins per the seller. My appraisers, i use many for different opinions, verified tourmalines per the internals of the stone, the RI of the material & color from existing data at the time, these apprs are not cranked out, usually takes @ 2-3 wks per report. Am enclosing a lab report on a alexandrite stone i paid pennies on the dollar for, latest appr for the 1 stone is over $30,000.00/stone, a conservative figure. I have several lab reports, not for every stone, not necessary, but for a favorite few. Watch what u read before opening mouth- [-X [-X 8) PS-am enclosing 1 of my appraisers, the latest & no slouch & a woman at that!


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 Post subject: Re: Purple tourmalines
PostPosted: Wed Aug 01, 2018 12:44 pm 
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ruby302 wrote:
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jason :twisted: someone should staple ur tongue, read before u write, i never said these were cuprian tourmalines, i stated they were bought on ebay, listed as purple tourmalines with the stated origins per the seller. My appraisers, i use many for different opinions, verified tourmalines per the internals of the stone, the RI of the material & color from existing data at the time, these apprs are not cranked out, usually takes @ 2-3 wks per report. Am enclosing a lab report on a alexandrite stone i paid pennies on the dollar for, latest appr for the 1 stone is over $30,000.00/stone, a conservative figure. I have several lab reports, not for every stone, not necessary, but for a favorite few. Watch what u read before opening mouth- [-X [-X 8) PS-am enclosing 1 of my appraisers, the latest & no slouch & a woman at that!
Before you put stapler away, here is my opinion. The reason you paid pennies on the dollar is because that's what it's worth. Any gem lab will give you a natural Alex. report. The muddy brown color change is neither valuable or desirable. Go on Ebay right now, there are thousands of these ugly, horribly cut stones. Conservative figure, 30K- not in any market, any country, any planet. These appraisals are completely useless and a waste of time..If it makes you feel good that someone tells you your 50 dollar stone is worth 50 grand ,then go for it. I remember looking up one of your appraisers (his name was Hill), he ran weekly Karaoke shows and did gem appraisals on the side. Kind of funny that I have hundreds of stones and zero appraisals.

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 Post subject: Re: Purple tourmalines
PostPosted: Wed Aug 01, 2018 3:04 pm 
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newark, we havent conversed in months-why ruin a good thing!! #-o Ur afraid of appraisers because U GOT NOTHING, EXCEPT BY MISTAKE!- :evil:


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 Post subject: Re: Purple tourmalines
PostPosted: Wed Aug 01, 2018 6:11 pm 
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:smt103 Come on lads....let's not throw stones (hehe)


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