Undetectable gem treatments

[morecarats]

There has been some discussion recently on the capabilities of different gemological laboratories. Basically the labs fall into two categories: those that do standard or traditional gemological testing, and those that have advanced instruments that can determine chemical composition and various kinds of gem treatments.

One point that has not been mentioned is that the science of gemological testing is still limited, and there are treatments which are currently undetectable by even the most capable labs.

Most labs do not publish lists of undetectable treatments, but you soon find out what they are if you have enough stones tested.

One lab that did publish a list of undetectable treatments with their test reports was the AGTA Gemological Testing Center. Among the undetectable treatments they listed were the following:

Beryl -- heat, irradiation
Chalcedony -- heat, dye
Fluorite -- heat, irradiation
Quartz -- heat, irradiation
Spodumene -- heat, irradiation
Topaz -- heat, irradiation
Tourmaline -- heat, irradiation
Zircon -- heat
Zoisite -- heat

I started to think about this issue recently when I had some beryl that I thought might have been irradiated, and I asked GIA Bangkok if they could test it for me. They replied that they could not detect irradiation for most gem varieties, which accords with the AGTA list.

 

[T L]

MC,
Thank you so much for opening this thread. I think it is very important, but I think you should reopen it when PS2.0 is up since this very important information will go away. I do find it disconcerting that many labs do not publish what they cannot detect, and the treatments are getting so advanced that many labs can't detect them.

In the meantime, I have emailed AIGS, and Dr. Massi (their director) to find out about be-treatment of corunudum and if AIGS can detect it. I think if not, I will just stay away from all sapphires. They're just way too "iffy" for me.

 

[Arkteia]

Please tell me what he said because I just ordered another blue sapphire! I am in love with these stones, but I''d like to know how safe it is to buy them!

 

[morecarats]

Please don''t confuse the issue of undetectable gem treatments with the capabilities of some particular lab.

Beryllium treatment of corundum can be detected using devices such as LIBS (Laser-induced breakdown spectroscopy) or LAICPMS (Laser ablation inductive couple plasma spectroscopy). Of course if a particular lab doesn''t have one of these devices, they won''t be able to do the analysis. But a number of labs are now equipped with these instruments.

 

[T L]

Crasru,
If you can't get a lab that will test for beryllium diffusion, I would no longer bother with sapphires. They diffuse them by the boat load, and they can be various shades and tones of blue. There is nothing to my knowledge, from viewing them with a microscope or standard gemological equipment, that would indicate a heated stone is not beryllium diffused.

From AIGS:

Thank you for your email. We are in the process of acquiring the machine that is able to test for beryllium treated sapphires. Having said that, please also note that natural sapphires may contain beryllium naturally. The test performed can only indicate the presence of beryllium (on locations tested) and cannot conclusively determine if a stone has been beryllium treated.

The HT designation on our reports means the stone is heated, but we do not test for beryllium treatment. However, we are in contact with a few different labs, and if needed can provide you the service required.


Best Regards,
Lindsay
Customer Service
AIGS Lab

 

[Arkteia]

OK, so I always buy unheated sapphires. But here is an interesting thing, the certificates now say, "not heated or color-enhanced by other known methods". What does it mean? That you can enhance color without heating the sapphire?

Also, information that there may be some traces of Be in untreated sapphires resemble me the situation with my demantoids. They were sold as unheated, for the price of unheated stones, and when GIA lab deemed them treated, the jeweler took them back, but shortly afterwards I read an article indicating that garnets could be ''normally'' heated by Mother Earth.

So I do not know where we are now with "natural" stones. I hope that my ruby, which was certified by GRS in 2004, is not Be-treated. It was re-certified by GIA, too.

 

[T L]

Some gems can not be determined as treated. Fancy green diamonds are a good example. The color can be caused by irradiation, man made or by mother earth. The problem for the GIA is that it can't determine if the diamond's radiation stain is caused by either situation. As for treating sapphires without heat, that's a good question, and I bet the powers that be are working on this in order to deceive. For now, as far as I know, only heated stones are treated, and the treatment can be anything from plain heat all the way to introducing foreign elements in order to diffuse or improve clarity.

The problem is that the treatment of stones to enhance them and make them more attractive is a big business, and people are making a fortune doing this. Unfortunately, for us, and the labs, it causes everyone to stay on top of these treatments and to always be diligent with your gem purchases. There are some gems that are not treatable in a positive way, spinels are an example, but I'm sure they're trying to get around that. It's always something with these treatments, and it's very disconcerting.

What is also very disconcerting are the super convincing synthetics that are coming on the market. They are ever becoming more and more convincing. I think the GIA is the only gem lab in the world that has a very expensive machine that can determine a synthetic diamond for example. Now that some man made diamond labs have learned to synthesize white diamonds, it's really scary.

 

[Michael_E]

Date: 6/2/2010 1:52:58 PM
Author: tourmaline_lover
I think the GIA is the only gem lab in the world that has a very expensive machine that can determine a synthetic diamond for example. Now that some man made diamond labs have learned to synthesize white diamonds, it''s really scary.

Not nearly as scary for you as it is for many of the mines of natural materials in the world. When the synthetics require an expensive test to determine their origin and their cost drops enough to allow them to flood the market, then naturals go right out the window. This has happened to amethyst and ametrine in that it is not worth the cost to test them and so the market is now composed mostly of synthetics. I have a feeling that this will also happen to diamonds...at least small ones. Since the bulk of the materials from any mine are small stones and since the selling costs of them will be higher than lab created stones, the costs of mining will not be met and most mines will shut down. This may even be happening now as it is nearly impossible to test for synthetics in diamond melee, (how do you do a $20 test on $10 stones ?).

 

[Michael_E]

Date: 6/2/2010 1:33:38 PM
Author: crasru
OK, so I always buy unheated sapphires. But here is an interesting thing, the certificates now say, 'not heated or color-enhanced by other known methods'. What does it mean? That you can enhance color without heating the sapphire?

Sure, it's a surface coating similar to coatings on camera lenses. If those coatings are diamond, then they will be quite tough and durable. I have recut certain types of synthetics which were clear and nearly colorless, but which turned brown after being cut, indicating that even synthetics are being treated to make them more attractive than in their "normal" state. There's a whole bunch of high tech methods to "improve" most gems and they are not easily detected. If the price is low enough then no one is going to bother checking them.

 

[T L]

Some synthetic diamonds do have cage fluorescence which can be spotted with a UV light, and some natural diamonds have inclusions that can only be found in natural material, but there are some synthetics out there that cannot easily be determined except by this expensive machine.

 

[Harriet]

Crasru, SSEF (the Swiss Gemmological Institute), for one, can and does test for BE diffusion. There's no need to be scared of sapphires.

 

[chrono]

Harriet,
The only problem with that is it doesn’t make financial sense to send it to SSEF for an inexpensive sapphire for BE testing.

Do you know which machine they use to do the testing? Is it LIBS or LAICPMS?

 

[Harriet]

LIBS. My point is that there are labs that can test for BE treatment. It is not to suggest SSEF in particular.

 

[pregcurious]

I read on another forum (not to be mentioned because of PS policy) that AIGS acquired a LIBS machine to detect beryllium diffusion for an extra $10.

Has anyone used this new service?

 

[Justin_Cutter]

Re:

MC,
Thank you so much for opening this thread. I think it is very important, but I think you should reopen it when PS2.0 is up since this very important information will go away.

So sorry for this minor derail but can you elaborate on this TL? Was a announcement made that I missed some how? Will all of our threads be deleted on PriceScope? That makes no sense why all the old archives could not be retained. Sorry the thought of everything being lost makes me sick on my stomach.

~Justin

 

[LD]

Re: Re:

MC,
Thank you so much for opening this thread. I think it is very important, but I think you should reopen it when PS2.0 is up since this very important information will go away.

So sorry for this minor derail but can you elaborate on this TL? Was a announcement made that I missed some how? Will all of our threads be deleted on PriceScope? That makes no sense why all the old archives could not be retained. Sorry the thought of everything being lost makes me sick on my stomach.

~Justin

Justin look at the dates on this thread. The upgrade happened ages ago. Some photos from the old system were lost.

 

[Justin_Cutter]

Re: Re:

MC,
Thank you so much for opening this thread. I think it is very important, but I think you should reopen it when PS2.0 is up since this very important information will go away.

So sorry for this minor derail but can you elaborate on this TL? Was a announcement made that I missed some how? Will all of our threads be deleted on PriceScope? That makes no sense why all the old archives could not be retained. Sorry the thought of everything being lost makes me sick on my stomach.

~Justin

Justin look at the dates on this thread. The upgrade happened ages ago. Some photos from the old system were lost.

Wow I feel a little silly. Thanks LD!

 

[LD]

Re: Re:

MC,
Thank you so much for opening this thread. I think it is very important, but I think you should reopen it when PS2.0 is up since this very important information will go away.

So sorry for this minor derail but can you elaborate on this TL? Was a announcement made that I missed some how? Will all of our threads be deleted on PriceScope? That makes no sense why all the old archives could not be retained. Sorry the thought of everything being lost makes me sick on my stomach.

~Justin

Justin look at the dates on this thread. The upgrade happened ages ago. Some photos from the old system were lost.

Wow I feel a little silly. Thanks LD!

If you're worried then you should copy everything. You can never guarantee that things will stay on any internet forum.