What lab to use in US ?

[arjunajane]

Hi folks,

I am looking for some input on what are my options with potentially having a tourmaline certified in the US -
in terms of the different labs, which ones should I consider?
And will they be able to confirm if the tourm is unheated and its origin?

If you know the info, please also post the cost of the corresponding report (or of course a link).

Each vendor I am speaking to I trust implicitly, however as I am considering a reasonably expensive stone
I am thinking about certification just for peace of mind.

Cheers in advance!
aj

 

[chrono]

AJ,
From what I’ve been reading and advised, heating of tourmalines can be detected but isn’t cost effective. How important is the fact that the tourmaline be unheated and its origin verified? Is there a premium for that particular stone? As far as I know, the AGL prestige report will tell you everything and more but it costs around $200 if I’m not mistaken. I know GIA will test for treatment too but may not give a report of origin. I am not familiar with the cost of the GIA cert/memo as I’ve only used AGL.

 

[T L]

AJJ,
If you're considering a pink tourmaline, I'm not sure that irradiation can be detected by the labs, even sophisticated ones. Heated tourmaline can still be expensive, like paraiba, and you almost never find it unheated and again, I think it's difficult/impossible to detect in tourmaline. I don't think heating significantly reduces the value in tourmaline like it does in corundum because it is done at much lower temperatures in tourmaline. As for origin, that is important if you're considering a paraiba, and the AGL prestige would provide that information. I think it's around $250 for the report with the origin, but you should contact AGL to make sure.

 

[morecarats]

To find out what testing a particular lab can do you really need to contact the lab.

I know in the case of the now-defunct AGTA lab, they actually published a list of testing limitations (i.e., undetectable gem treatments) on the back of each report. Included in the list were irradiation and low temperature heating of beryl, tourmaline and a number of other gem varieties. But since gemological science is always progressing, AGL may be able to do more.

 

[arjunajane]

AJ,
From what I’ve been reading and advised, heating of tourmalines can be detected but isn’t cost effective. How important is the fact that the tourmaline be unheated and its origin verified? Is there a premium for that particular stone? As far as I know, the AGL prestige report will tell you everything and more but it costs around $200 if I’m not mistaken. I know GIA will test for treatment too but may not give a report of origin. I am not familiar with the cost of the GIA cert/memo as I’ve only used AGL.

Hi C,

when you say 'isn't cost effective' do you mean the cost is prohibitive to the consumer?

To answer your question, I guess it's not really that important, as I said I know and trust the vendors I am speaking with.
There is one vendor I am considering a stone from who I have not dealt with before, but is respected through this board -
perhaps that unfamiliarity was my main reason for asking.

I think also I have been somewhat influenced as there have been a number of threads / comments recently that many on CS believe it necessary to get a report on a stone that costs ~1k or higher, which this one will.

May I ask Chrono do you get certificates on your more expensive stones?
Cheers for the info on AGL - I think ~$200 would be the maximum I would be willing / hoping to pay..I am checking out their options and fee schedule now.

 

[arjunajane]

AJJ,
If you're considering a pink tourmaline, I'm not sure that irradiation can be detected by the labs, even sophisticated ones. Heated tourmaline can still be expensive, like paraiba, and you almost never find it unheated and again, I think it's difficult/impossible to detect in tourmaline. I don't think heating significantly reduces the value in tourmaline like it does in corundum because it is done at much lower temperatures in tourmaline. As for origin, that is important if you're considering a paraiba, and the AGL prestige would provide that information. I think it's around $250 for the report with the origin, but you should contact AGL to make sure.

Hi TL,
thanks for the reply. No, not a pink or paraiba - I'm buying a blue-green, which I understand can also be routinely heated.
But some can also come natural with no heat - I would of course prefer all natural colour, but if heating is a 'trade standard' than I guess its not a huge deal to me.

I've just checked AGL - it appears you can have the Prestige report with origin, ID and enhancement for $150USD up to 3cts, $250 over 3cts (these are 'foundation member' prices). You can than have the Prestige report with origin, ID, enhancement and grading for $200 or $350, respectively.

So, in your opinion you would not obtain a cert for the kind of stone I am buying?

 

[arjunajane]

To find out what testing a particular lab can do you really need to contact the lab.

I know in the case of the now-defunct AGTA lab, they actually published a list of testing limitations (i.e., undetectable gem treatments) on the back of each report. Included in the list were irradiation and low temperature heating of beryl, tourmaline and a number of other gem varieties. But since gemological science is always progressing, AGL may be able to do more.

Hey MC,
of course you are correct - it is more accurate to go to the source for such info.
But it is also easier and quicker for me to ask the other PSers, and perhaps learn something in the process

I think I will email AGL and ask if they can detect low temperature heating of tourmaline.

Apart from GIA and AGL are there any other recommendations at all?

Cheers ladies.

 

[chrono]

AJ,
For me, it also varies by stone. For some, it isn't necessary as it is obviously natural and the gem type is never treated. For others, I have the cert to be sure it isn't a synthetic, isn't heated (diffused) or to prove that it is coloured by cobalt as advertised.

 

[T L]

AJJ,
If you're considering a pink tourmaline, I'm not sure that irradiation can be detected by the labs, even sophisticated ones. Heated tourmaline can still be expensive, like paraiba, and you almost never find it unheated and again, I think it's difficult/impossible to detect in tourmaline. I don't think heating significantly reduces the value in tourmaline like it does in corundum because it is done at much lower temperatures in tourmaline. As for origin, that is important if you're considering a paraiba, and the AGL prestige would provide that information. I think it's around $250 for the report with the origin, but you should contact AGL to make sure.

Hi TL,
thanks for the reply. No, not a pink or paraiba - I'm buying a blue-green, which I understand can also be routinely heated.
But some can also come natural with no heat - I would of course prefer all natural colour, but if heating is a 'trade standard' than I guess its not a huge deal to me.

I've just checked AGL - it appears you can have the Prestige report with origin, ID and enhancement for $150USD up to 3cts, $250 over 3cts (these are 'foundation member' prices). You can than have the Prestige report with origin, ID, enhancement and grading for $200 or $350, respectively.

So, in your opinion you would not obtain a cert for the kind of stone I am buying?

AJJ,
The only tourmaline I know of that has a premium for origin is Brazilian Paraiba. Therefore, for example, if you are buying a blue green Afghan that looks identical to a Namibian, the origin really makes no difference at all. Blue greens are sometimes heated, but that heating doesn't really affect price, therefore, I wouldn't waste my money on a prestige report. You may want to id it as natural with a gem brief, but that's as far as I would be willing to go. Hmmm, is the stone from John Dyer?

 

[arjunajane]

AJ,
For me, it also varies by stone. For some, it isn't necessary as it is obviously natural and the gem type is never treated. For others, I have the cert to be sure it isn't a synthetic, isn't heated (diffused) or to prove that it is coloured by cobalt as advertised.

Hey C,

fair enough, this makes sense. Cheers for your input lovey

 

[arjunajane]

AJJ,
If you're considering a pink tourmaline, I'm not sure that irradiation can be detected by the labs, even sophisticated ones. Heated tourmaline can still be expensive, like paraiba, and you almost never find it unheated and again, I think it's difficult/impossible to detect in tourmaline. I don't think heating significantly reduces the value in tourmaline like it does in corundum because it is done at much lower temperatures in tourmaline. As for origin, that is important if you're considering a paraiba, and the AGL prestige would provide that information. I think it's around $250 for the report with the origin, but you should contact AGL to make sure.

Hi TL,
thanks for the reply. No, not a pink or paraiba - I'm buying a blue-green, which I understand can also be routinely heated.
But some can also come natural with no heat - I would of course prefer all natural colour, but if heating is a 'trade standard' than I guess its not a huge deal to me.

I've just checked AGL - it appears you can have the Prestige report with origin, ID and enhancement for $150USD up to 3cts, $250 over 3cts (these are 'foundation member' prices). You can than have the Prestige report with origin, ID, enhancement and grading for $200 or $350, respectively.

So, in your opinion you would not obtain a cert for the kind of stone I am buying?

AJJ,
The only tourmaline I know of that has a premium for origin is Brazilian Paraiba. Therefore, for example, if you are buying a blue green Afghan that looks identical to a Namibian, the origin really makes no difference at all. Blue greens are sometimes heated, but that heating doesn't really affect price, therefore, I wouldn't waste my money on a prestige report. You may want to id it as natural with a gem brief, but that's as far as I would be willing to go. Hmmm, is the stone from John Dyer?

Hey TL,

Thanks for your input, I'm glad for the other opinions.

The stone may or may not be from John Dyer

You can bet as soon as I've made a decision you guys will know though.

 

[klewis]

Hi Arjuna -


A lab may be able to detect that a tourmaline has been heated, but it would be harder for them to say conclusively that it has not been heated. For example, heat treatment might be detected from studying inclusions - thermal expansion, but if there are no significant inclusions, treatment may not be able to be determined. That's my understanding of it from questions I've asked.

Of the two tourmalines I have from John Dyer, he states:

"Heating is a common treatment in Tourmalines, to find one without treatment is relatively uncommon. To our knowledge however it is not possible for a gemmological laboratory to prove whether or not a cut tourmaline has been treated. We believe this gem to be untreated due to information obtained from our rough suppliers and also the fact that the rough still had it's original crystal "skin" and in our experience when tourmaline is heated prior to removing this skin it usually breaks"


Good luck with your possible purchase!

 

[arjunajane]

Hi Arjuna -


A lab may be able to detect that a tourmaline has been heated, but it would be harder for them to say conclusively that it has not been heated. For example, heat treatment might be detected from studying inclusions - thermal expansion, but if there are no significant inclusions, treatment may not be able to be determined. That's my understanding of it from questions I've asked.

Of the two tourmalines I have from John Dyer, he states:

"Heating is a common treatment in Tourmalines, to find one without treatment is relatively uncommon. To our knowledge however it is not possible for a gemmological laboratory to prove whether or not a cut tourmaline has been treated. We believe this gem to be untreated due to information obtained from our rough suppliers and also the fact that the rough still had it's original crystal "skin" and in our experience when tourmaline is heated prior to removing this skin it usually breaks"


Good luck with your possible purchase!

Hey klewis,

Cheers for your post - this is very helpful info, I appreciate it.
It is interesting the differing opinions on this..

Just for the sake of some extra info, I sent off a query to AGL yesterday and received a response straight away - I told them I was asking about having an Afghan blue green tourmaline certed from a trusted source, with a prestige report - the response came:

"On Tourmalines of this color we only determine origin if it is copper bearing material. We will test for any treatments present. If the stone turns out to be copper bearing then will will issue an origin."


So the respondent to my query seemed very confident that they could detect treatments; although, I have sent a follow up email also yesterday asking for more information, and am yet to hear back.

Most likely I will not pursue a cert for this stone after the advice received here, but I think it will be interesting to see what AGL says in comparison to cutters such as John and others on the board..