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- Sep 20, 2008
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Arcadian|1301599747|2884429 said:Hi Josh![]()
So TL, wouldn't AGL have the equipment to identify such a stone and its location? According to GRS, there's several techniques used for this.
From GRS from their 2009 study:
"We found it useful to investigate the origin based on chemical fingerprints using different methods, including EMPA, LIBS, LA-ICP-MS and ED-XRF analyses. Based on these analyses, it was found that the chemical composition of copper-bearing tourmalines from Mozambique, Nigeria and Brazil show distinct differences, which are sufficient selective to determine their origin"
I would assume that all of the major labs have the ability to test for location, or at least I would find one that could.
If clarity enhanced, I would assume that could be found out rather easily under a microscope by an experienced person. I know there is talk of using several types of CE's from oil to Opticon. Many of these have been easily found under a microsocope.
I don't know what a lab report from the 90s would have done, considering the evolution of processes today. I also don't doubt there's cutters out there with stuff they've held on to over the years that they never figured they'd have to send to a lab right away.
I'm going to post some information I found on GRS website. I'm still reading through this, as its quite extensive. I've gotten a lot of great info though.
http://www.gemresearch.ch/journal/No9/page01.htm
He does make mention that the heated stones were mostly blue/green and that not all the purple tourms were unheated. I'm still trying to read through how that determination was made.
High valuable copper-bearing tourmalines occur in different color and large size and are produced in Brazil, Mozambique and Nigeria. The sizes and distribution of these gemstones in the gem market were studied and a statistic about the trade has been published in this report. These types of tourmalines include many different color varieties and are found as heated as well as unheated gems (Fig. Par07 and 12). Unusual large sizes have been found from the mines in Mozambique. The majority of the stones have been heat-treated in the greenish-blue to blue colors, whereas the purple and green colors are more frequently spared of thermal enhancement (Fig. Par07). These findings are in good agreement with the findings from heat-treatment experiments (Lit. Par33), which predicted that heat-treatment of green colors, is possible with limited success only. Copper-bearing tourmalines from Brazil such as from the state of “Paraiba” were more often found to be unheated than Mozambique tourmalines. Gem quality “Paraiba”-tourmalines does occur in much smaller sizes than the African counterparts, but they are generally more saturated in color. According to our opinion, large-sized unheated gem-quality tourmalines from Brazil (Paraiba or Rio Grande do Norte) with intense “neon”-blue colors can be described as extremely rare (See Fig. Par07, 08, 11 and 12).
There's much more in that report that I have to read and understand, but its slow going. *i'm not a scientist*
Now, by the same token, anything you buy, unless you don't get it out of the ground yourself, or know every single person in the supply chain, you have to have faith in the seller that hes disclosing any and all treatment information. Then you have to be able to verify it.
But from what you've said TL it can't be verified.
On undetectable treatments like radiation, thats been going on for some time apparently.
Here's a few other studies I found on tourmalines
published in 1975
http://www.minsocam.org/ammin/AM60/AM60_710.pdf
and in 1988
http://www.minsocam.org/ammin/AM73/AM73_822.pdf
Another from 1988 on Gemstone irradiation
http://lgdl.gia.edu/pdfs/ashbaughw88.pdf
So if they were doing this stuff then, what does that say about the tourmalines we've got now? does that mean that anything after 1975 is possibly irradiated? maybe, I don't know, I'm still reading to find that out.
I know you trust your source TL, but I have to say, being his wife sells gems and jewelery, I put in him the realm of vendor. This is not saying that his info is bad, Its saying at the end of the day, they sell stuff too.
Everyone should do their own research as much as they can, and also have some measure of trust that the seller is disclosing any and all treatments. If you can't trust the seller is disclosing to their knowledge true information about a thing, then its a good policy to not buy from them. I take that to heart anytime I buy a gemstone these days, because of the level of stones I'm now buying! this ish gets xpensive!
I research everything I can like mad, because I at least want to be educated about what I'm buying. And while I do rely on others experience, I still try to find that proof myself.
So I do appreciate the information given TL, I don't want o you to think otherwise, but I also have to say that I will disagree with some of it. Josh's company is selling the stone true, but I also don't think they'd be willing to mess up their longstanding reputation either. Pricescope is good and bad for some vendors, that is something I'm sure they're all aware of.
The stone to me dosen't look bad the cut is very nice which I think makes the stone look quite lovely. Color saturation looks very good to me without being too dark. Being the stone was taken with a Canon Powershot G3, I'm sure whomever took it bent over the stone to get the shot.
And in the case of these stones, didn't you say that copper bearing stones don't always show their beauty in pictures? We also know that pricescope kills pictures. On my home screen when I open the picture, its very nice looking.
Region of where the stone is from can be verified. The heat issue, well generally 600cc on a tourmaline isn't all that high, but there may be other markers that the stone is unheated, I'm reading about this right now to see if it can be determined. Filled fractures, if they were filled, likely can be verified as well.
So to me, it makes sense to do background on the vendor, engage the vendor to see if both of you meet eye to eye, ask questions about the stone, have the stone checked by an independent 3rd party. A sale of a stone of this caliber should always be contingent on a lab report. If I were to move forward, thats exactly what I would do.
Treatments will always evolve, And that means you either stop buying until those treatments are detectable or, you get educated and make a decision on what for you is the best possible way to go. For some that means they don't buy anything, for others, they do and enjoy it for what it is.
Colored stones is crazy but well. isn't life?
-A
Hi A.
It's not that I completely put all my trust in whatever my source has to say. The problem is that I am having difficulty finding any additional information that refutes with what he has to say (as I have been doing my own research), as far as irradiation detection in tourmaline is concerned. That being said, I do believe the AGL can provide the origin of these stones, which may be of some comfort, but that does not guarantee they are not irradiated or not heated to my knowledge. I just believe people should exercise caution these days when buying indicolites, especially those that are very expensive. There are some gems that do have detectable treatment, and by all means, I feel they are safer to buy with reputable lab reports. I will probably stop buying anything the day all gems have non detectable treatment and consider myself lucky for the few natural colored gems I currently own.
I did see those articles on irradiated tourmaline, but I think they were done to a small few, on a limited basis. The treatment may have been too expensive back then to conduct on such material on a widespread basis. With the recent advent of nuclear accelerator facilities in Brazil that can mass irradiate tons of gems, including tourmaline, it is more widespread.
Beauty is in the eye of the beholder Arcadian, and if you love the color of that tourmaline in the second photo, then that's fine. I would be lying to you if I told you I loved it, as I do not, and I did look at it on my good monitor. I'm worried it will be overly dark in person. However, I do agree with others that viewing a stone in person is best, as PS does sometimes kill the color of some photos. However, the more neon stones tend to be lighter in tone, and more of that turquoise color, which this is not. I also don't know who Josh is, and I've never heard of his company before, so I'm not sure of his reputation and his vendor reliability, so I can't comment there.