Gem Lab... AGTA, AGL, GIA?

[katbadness]

In the diamond world, the definitive lab seems to be GIA, with AGS being close second.. and then the rest of them.. (HRD, EGL).

In the colored gem world, is there a definitive independent lab like GIA?

What are your thoughts (pros and cons) on the different colored gem labs out there (GIA, AGTA, or AGL)?

As a side question, is it worth it to get a stone that is not only tested for the usual gem treatment but is also color graded? I''m curious what the color grading means to a normal consumers like me...

 

[valeria101]

Hm... I don't know. Worse: I have no idea who can give a grade to these labs from a position of authority so I can cite it! However, the grading of colored stones is not as standardized as it is for diamonds (by far) so any lab's grades would not determine prices as closely as diamond prices determine price. Beyond pricing... what are grades good for ?

Here's one inspired, short take on the issue ( from Reginald C. Miller, Inc.):

" Gems Certificate
Gems

While there are many gemological labs around the world, only a handful have established themselves, to varying degrees, as acceptable certifiers of colored gemstones at this time. In no particular order, gemstone collectors value most the The American Gem Trade Laboratory (AGTL), American Gemological Laboratory (AGL), Gubelein Laboratories, The Gemological Institute of America (GIA), and the GemResearch Swisslab (GRS).* Notwithstanding, some of the gems you will see on our site remain uncertified. Why? Because colored gemstones, unlike diamonds, typically do not trade "with certificates" in the primary or wholesale markets. We do, however, guarantee all of the gemstones sold on this site to be exactly as presented, and encourage certification as a verification of our experts' opinions. Be prepared for varying opinions, nomenclature and standards, as colored gemstones-- unlike diamonds-- do not yet have a common "language." When you see a gem that has no certificate, it will usually imply unless described otherwise that the gem has been subject to a certain type of enhancement.

*Note: This listing does not imply our endorsement of any one lab, nor does the exclusion of a lab imply that it is not considered reputable. We are simply echoing current popular market opinion. "



My (hopefully humble sounding) interpretation ?

It's great to get an explanation of what the seller's grading and disclosure policy is. Would I then want a cert? Not from my jeweler!

Perhaps the "gem collectors value most" part if key here. Most gems are bought and sold with no papers, from petty to grand - every single day

If one wants a certificate, it is easy to see which lab provides the type of information you find useful (enhancement, origin, color) on their papers and forget the rest. Aside this, unless whatever the lab certifies has a huge impact on value and cannot be reproduced without high-tech tools, why bother... basicaly.

For example, these colored gem certs come with a list of what tests have been performed to reach a certain conclusion (enhancement status or origin, for example). It is possible to order extra testing if available... Diamonds are suposedly graded in a standard setting, so none of this would make sense.

Color? I would not worry. These certs are much better at telling enhancements, but not very useful in telling the quality of the piece (let alone value) at hand. GIA promotes a set of color codes and references... and whichever lab uses it would say so. However, the color crible is much wider than diamond color grades. One can point out the color components on a precise, hair-splitting scale, but then what? Prices would definitely not follow such subtle differences.


I know there must be more and better to say. Hope this thread gets LONGER!

 

[elmo]

I'm not an expert but here are some things I've observed and heard.

For the really world class stones that sell at major auction houses, I think I've seen more Gubelin reports than anything else. A dealer whose opinion I trust also places Gubelin at the top of the list.

It is interesting that Miller left off SSEF. I'm still trying to decide for myself whether GRS carries the same reputation as SSEF and the rest of the labs mentioned.

I have the idea that AGTA and AGL reputations for reliability are similarly good, but they are different organizations and issue different sorts of reports. AGTA is a trade organization whereas AGL is a small operation that's working for their clients (consumers) in much the same way that Dave Atlas and Rich Sherwood here do. An AGTA report covers treatments and (optionally) origin but it's not a "grading" report in that it says nothing about "quality". Although it's just one guy's opinion, a full AGL report attempts to grade all relevant aspects of a stone's quality. Cap Beesley at AGL will talk with you on the phone about the relative merits of a potential purchase like the appraisers here will do; I'm not so sure AGTA will do that.

Since as I say I'm not an expert, I like that AGL will take a stand on quality like this. If I'm buying something fairly expensive, I think having the full AGL report helps protect my investment, in a similar way as an AGS DQD for an ideal-cut diamond does.

The simple AGTA id report will cost you a lot less than a full AGL report...something to consider for less expensive stones.

 

[mogok]

***NOTE: On this post I mistakenly indicated that GRS was in partnership with "CK Gems". I have been informed by GRS that this information is incorrect, so I have deleted this sentence and I regret any misunderstanding that it may have caused.***

Hum...

That's an interesting subject.

You ask if there is "an independant lab like GIA?"

Well "independant" is a serious point while speaking about laboratories: AGTA is not that independant as it is linked with the US traders, GIA? Well...

In fact a laboratory is never completly independant: As an "independant laboratory" is first of all a business it depends on his customers. If a customer is very important in terms of business, it is probable that for borderline cases then the laboratory will give "the most favorable grade" possible.

If you ask which laboratory are good in colored gemstones then, i will say that it depends what you are searching for!

If you want to know if your stone is a ruby, a spinel,... Then I think that any lab can do the work good, and no need for that to pay the high fees of the top labs that are Gubelin (The world best laboratory to my knowledge), GIA, SSEF (In basel, Switzerland), AGTA,...

In Yangon, Burma for exemple I would trust any of the 5 labs of the city for that and they will charge something like few dollars to do the job.

Now if you want to go to treatments, then better to go to a lab that used to see these stones regularly: Labs at the source of the treatments in Bangkok for example, with their gemologists looking everyday at dozens of rubies and sapphires are probably more aware of these things than many western labs which gemologists see such stones only once a while when these stones have reached their custumers market (it means several months or year after the bangkok based labs...)
Top world class lab like Gubelin are coming regularly in Bangkok for reseach projects and to visit cusotmers there. Few westerns labs can afford doing the same.

Now about this, it depends also about their policy for disclosure, their service, and of course what you are searching for.

The more difficult step about gemstone identification is origin. The labs giving origin are usualy to big ones because they have important database and advanced equipments. To give an origin on a clean stone that was heated several times is a real performance or a complete crook work!
History prove that even top labs like GIA or Gubelin can make mistakes... Origin is opinion whatever!

About grading as you say there is not internationaly accepted standart. Quality is a very subjective subject as some market will favor color, other cutting, other clarity, depends on the stones. The only true grading that matters to my view is the market, and colored gemstone market has nothing to see with diamond market. Grading report are to my knowledge more marketing tools than something else:
Show your stone to some people in the business and try to get offers: This will give you the real value of your stone...
I've studied several colored stone grading systems, and I have to say that I'm not very happy with them.
Grading beauty and art cannot really be made by science. Fine gems are artpieces...

But as GIA makes a lot of money with his diamond grading system, many are thinking to do the same for colored stones...
Up to know, to my knowledge: They failed. Labs are doing business on colored stones because of the presence of imitations, treatments, synthetics and with the romance of origin.

So which lab is the best? I will say: The one that your customer will trust. It can be any lab or just a few ones depending of him. lab business is all about persons (brand name gemologists, datas and communication)
It all depends at the end about what you want: If you come to see somebody with a Gubelin report it has something impressive. If you come with a report from a local burmese lab it will be less impressive but it does not mean that you customer will be less likely to buy the stone. Depends your way to speak about it and the price he is ready to pay to get this "opinion report".

Laboratories reports are just the "third person opinion" in a gem deal. They bring some security to a deal.

 

[WinkHPD]

Wow! Mogok, that was a great response. Thank you for taking the time to share so much "opinion" with us!

Your comments about the various labs and their relative usefullness depending on what one is looking for are brilliant. In this country for average stones an AGTA or GIA paper is probably sufficient. Most people here have not heard of Gubelin unless they are already serious collectors and once I offered a Gubelin certed stone to a client who only wanted to buy if GIA concurred with the Gubelin report. He was unmoved by my comment that it was like asking your high school math teacher for a second opinion on Einsteins Theory of Relativity.

I especially loved: "Laboratories reports are just the "third person opinion" in a gem deal. They bring some security to a deal."

If more buyers would buy with their eyes and only use the reports for security I think they would be better served. I have seen heated stones that far surpassed untreated stones in beauty buy had the buyer pay more for the less attractive stone because of paper. (These stones were for personal adornment not "investment")

Any way, thank you for such an informative post. Enjoy your life in the trenches!

Wink (who would be jealous about being stuck in the states except for his wife and kids who bring him so much joy)

 

[elmo]

In many ways I agree with you both. A also expect that Mogok's personal gem quality rating system is rather distinct from Cap Beesley's and possibly Wink's and for that matter potentially anyone who is into this seriously. The more experience you have, the more certain nuances and styles stand out and make for a particularly special stone example. And I think that's part of Mogok's dislike for any quality grading system.

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On 5/23/2004 10:32:01 AM Wink wrote:


If more buyers would buy with their eyes and only use the reports for security I think they would be better served.
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I have to take some issue with this however, particularly for an expensive item, since I think it can take a certain amount of experience and expertise or "connoisseurship" to appreciate the subtleties of why for instance one sapphire costs say X dollars, why another one costs 3X, and why one of two at a similar price might have more going for it than meets the casual inexperienced eye. I think that it can be naive for the inexperienced shopper to simply trust their own eyes with something like this.

 

[strmrdr]

Wink raised a great point that I really agree with.
I dont care if its heated, not heated, nuked, or synthetic as long as it looks awesome and the price reflects the status.

 

[WinkHPD]

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On 5/23/2004 10:32:01 AM Wink wrote:



If more buyers would buy with their eyes and only use the reports for security I think they would be better served.

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I have to take some issue with this however, particularly for an expensive item, since I think it can take a certain amount of experience and expertise or 'connoisseurship' to appreciate the subtleties of why for instance one sapphire costs say X dollars, why another one costs 3X, and why one of two at a similar price might have more going for it than meets the casual inexperienced eye. I think that it can be naive for the inexperienced shopper to simply trust their own eyes with something like this.

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Actually I think we are pretty much in agreement here, all three of us. If you buy what you like, and make sure that the paper says you are getting what you are seeing, then you are being well served by both your eyes and your paper. I agree with you that for a novice to go around paying steep money for things he does not know that the paper is indeed a great security.

As for grading systems, again I must agree with Mogok, all have tried to quantify color and none have totally succeeded. Add in the quality of cutting and wonderous things can happen to value. Once I had Richard Homer cut a 7 + carat fine Burmese sapphire that had an AGL certificate. it finished out a little better than 5+ carats. Cap was astonished at the stone when it was returned to him for re grading and he found that all catagories but one in his color descriptors had improved, including saturation and hue. Cut DOES matter to colored stones, as the longer the light bounces around in there the more color it absorbs.

How do you quantify the magic that is showing in this stone?

When you see it, even in this woefully inadequate photo, you know that you are looking at something VERY special. You do not need a cert to tell you this, although for the money that this stone commands, the paper will bring you great comfort.

Wink

 

[WinkHPD]

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On 5/23/2004 3:53:34 PM strmrdr wrote:

Wink raised a great point that I really agree with.

I dont care if its heated, not heated, nuked, or synthetic as long as it looks awesome and the price reflects the status.

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Thank you. It is a shame that there are so many in the world who would take something beautiful and defraud people with it. These are the people who make it so profitable for GIA and AGS and other labs to exist.

In today's world it is very hard to keep up with the new ways created soley for the purpose of deceiving, which is why the labs provide such a great service, not just to the consumer, but also to the jewelry trade members.

Wink

 

[mogok]

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On 5/23/2004 2:57:55 PM elmo wrote:

In many ways I agree with you both. A also expect that Mogok's personal gem quality rating system is rather distinct from Cap Beesley's and possibly Wink's and for that matter potentially anyone who is into this seriously. The more experience you have, the more certain nuances and styles stand out and make for a particularly special stone example. And I think that's part of Mogok's dislike for any quality grading system.

Well thats true that I've not a very high esteem of GIA color grading system for example: How can you grade dichroic rubies and sapphires with pieces of amorphous plastic? Even for spinels its impossible... Plastic does not offer enough varieties and if this system is fine to grade GIA gemological schools fish tank quality stones or to note that an aquamarine does not have the same color than a sapphire, its very difficult to use when you try to work with fine stones.
The only thing I find positive about it, is its educative qualities in order to make people understand about hue, tone and saturation with something visual.

AIGS was proposing few years ago a type based system for rubies and sapphires that looks works much better and that had the advantage to be able to give an indicative price at the end. But currently with the disparition of Thai rubies and the arrival of new colors with the new treatment involving beryllium, new types have to be defined and the system needs some up date. This system was ruby and sapphire orientated... It was not doing miracles but it was quite efficient because it was using genuine stones as masters.

To my ideas most of the grading systems are trying to put numbers on stones: a slpR 5/6 ruby... It looks more scientific. Grading beauty with numbers is a little bit non sense to me as the final customer does not understand these numbers at all, but as any human being, he is fully able to appreciate beauty. It is putting numbers on a stone in order to put $$ in some people banks.
May be I'm too artistic and some people are not so they like to get a grading of the stone they buy in order to feel more confortable with it.
Personally when I buy a stone I love it for some reason, and I will sell it and make it be appreciated by my customer for this reason also...
No need a grading system for that.

Lab reports are different: Not everybody can identify correctly a stone. There is a need for them in order for the customer to be sure about what he is buying. Beauty is so subjective and personal:

I love native cut stones (it does not looks to be the same with many people i see here, but its OK) Of course I also like any quality in a gem but I love my stones same my girlfriend because I can stand her "imperfections" that looks sweet to me and makes me feel good with her. I dont need a grading system to tell me that my girlfriend is "slpR5/6 VVS" to fall in love with her. So it is with my gems:

I choose my stones for their imperfections that have to be below some standarts if the minimum qualities are present. Thats the way my master set is build.

Well this is as usual my very personal opinion.

All the best and hoping not to have bored you...

 

[valeria101]

Bored Mogok?

I should be insane for that! This chat is right among the best PS moments yet... It is just great to have a candide description of what intermediation services (grading) are good for at the different stages of the market (yours, Wink's, my own). Believe it or not, it takes months of reasearch to learn this much from outside the trade, just to be able to say "in theory..."

Thak you very much to all

 

[mogok]

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It is just great to have a candide description of what intermediation services (grading) are good for at the different stages of the market (yours, Wink's, my own).
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Well, about my market: I've no market really: I've nothing really to sell as I work in a Gemological Laboratory and in a Gemological School...
My cooperation with gemwow.com is a part time evening and week-end job, it is for me a way to stay close to what happen in the gem trade in Burma which is my main interest.
All the best,

 

[katbadness]

Hmmm... this thread has certainly taken a life of its own, which is great!!

It will take me a while to sort out all the posts and figure out what else to ask.

In the meanwhile, thank you for all the input! Your help is much appreciated!!

 

[valeria101]

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On 5/24/2004 12:43:03 AM mogok wrote:


Well, about my market: I've no market really:


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Oh my... I'll never get those words exactly right

I just meant "perspective", "position", "angle" not "business interest"... From where I stand ( a pile of economics books) "market" is a rather abstract notion, and I was simply delighted at the practical lesson of international trade this PS colloquium had turn towards