Would you get GIA or AGL for colored gemstones?

[prs]

I believe the most trusted lab for jade in Asia is the Hong Kong Jade and Stone Laboratory.

 

[icy_jade]

The top 3 labs that top auction houses will rely on:
- Gubelin
- SSEF
- GIA
I don’t think you can go wrong going with them for most stones.

For jadeite I think is Hong Kong Jade and Stone Laboratory as @prs has mentioned. That’s the lab I most prefer for jadeite.

In Asia, GRS is recognized and used often by sellers as it provides the color names like pigeon blood, royal blue, etc which customers like.

Lotus isn’t as recognized as GRS

GIT in Thailand is linked to a university or government linked (I can’t rem) and considered reliable.

In Singapore, NGI is the trusted lab and very strict (anecdotally tends to be conservative and may grade color etc a grade lower than the more established labs).

Not all the in-country labs are considered reliable. Some apparently are more willing than others to indicate certain trade desired names like pad or cornflower

Anyway for the OP given the type of stone, cutting and price, I think GIA will serve the purpose

 

[T L]

"Borrow" equipment? You make it sound like GIA loans it out.
All he would do is send it off to GIA and use their report. All he would "borrow" is their expertise, then tack on his own charge and send you GIA's findings in his report.
Why would I take the long way round if I could just get it straight from GIA and only pay one lab, not two?

Christopher Smith looked at my stone personally as he does most if the gems that come to AGL. I trust his expertise. He was honest and could not diagnostically test for diffusion. Why bother ruining his reputation on false facts, and again, I see no reason why using another lab’s equipment, but his expertise, is such an issue.

Honestly, it seems you dislike AGL for some reason based on prior remarks in this thread. If you know something, then share it. I do not dislike GIA, I just prefer AGL for the reasons I mentioned including the personal customer service, science based full color quality report, and reputation. These are huge factors to me. If I was purchasing an inexpensive colored gem, GIA would suffice.

 

[T L]

SSEF, GRs, and GIA are all trusted labs. I just take issue with how they grade color quality. Using flowery metaphors is not helpful. I don’t even think GIA grades color quality in anything but FCD’s. It just identifies hue.

 

[T L]

I regard Lotus Gemology very highly. Other than that of course GRS. I would also based on word of mouth trust Nanyang lab in Singapore.

Do they have access to a mass spectrometer?

 

[Arcadian]

@icy_jade @prs @voce Thanks for providing good and reliable information about the asian labs. My knowledge is poor in this area so thank you for educating me.

Maybe we should be making lists as to what lab is better at what type of gem. I mean sure I could send a diamond to GRS or AGL but would I normally? No. I'd send to a more diamond-centric lab. My thought would be the same with gems like jade.

 

[T L]

@icy_jade @prs @voce Thanks for providing good and reliable information about the asian labs. My knowledge is poor in this area so thank you for educating me.

Maybe we should be making lists as to what lab is better at what type of gem. I mean sure I could send a diamond to GRS or AGL but would I normally? No. I'd send to a more diamond-centric lab. My thought would be the same with gems like jade.

I would send the following gems to AGL,

Corundum (any kind)
Alexandrite
Emerald
Paraiba

I’m ok with GIA with other kinds of tourmaline, chrysoberyl, garnets or other gems (as long as you know there’s no clarity enhancement). I cannot speak to jade, but I think you need a lab that can rule out dying or other enhancements. I’m not sure how other labs define color quality for jadeite. Nephrite probably is less concerning.

GIA is the leader and has the final say on FCD’s. They also have the rare equipment to test for synthetic diamonds.

 

[voce]

Do they have access to a mass spectrometer?

I have no idea, but I'm sure the man who wrote the book on ruby and sapphire would know when such equipment is necessary.

I'm not disputing any facts mentioned by other members about what labs are used by auction houses, but as a consumer who doesn't buy from the auction houses, I like the level of information provided by AGL and Lotus. The people who head those labs are well respected in the trade, and the fact that GIA is used more by auctioneers speaks in my opinion more to the fact that GIA had been around for a longer time and is a larger establishment (therefore more recognized by older wealthy people who are not necessarily collectors of gemstones) than to the idea that it's better for ruby or sapphire.

I don't think any lab but AGL gives a color quality rating, although I believe that GIA can identify treatments in jade.

Very few people go for the full grading report at AGL, only those who are confident they have a quality gem, because the grading criteria is harsher than what vendors like to present to buyers. I imagine even for auction house stones, there might be such a fear that not everything will be graded as excellent. For example, some large gems might have excellent color but only 60% brilliance and only good cut. Such information does not move auction goods!

 

[prs]

The US auction houses almost always use AGL for colored stones, although you sometimes see GIA certs on less expensive gems. Always GIA for diamonds, of course.

 

[Arcadian]

I heard back from Lotus and they test for BE in sapphires using a couple of methods, LIBS being one of them.

 

[T L]

I imagine even for auction house stones, there might be such a fear that not everything will be graded as excellent. For example, some large gems might have excellent color but only 60% brilliance and only good cut. Such information does not move auction goods!

... or any vendor goods in general. It’s easier to move a myriad of various qualities of rubies as “pigeon blood red” for example, then to give it a true scientific and objective quality.

As for Lotus, although I highly respect Richard Hughes, I personally feel uncomfortable recommending this lab unless they do have access to a mass spectrometer.

 

[T L]

I heard back from Lotus and they test for BE in sapphires using a couple of methods, LIBS being one of them.

LIBS doesn’t catch all elementary particles. The LA-ICP-MS is more accurate. Sometimes they can catch diffusion or rule it out with standard equipment.

 

[Probee]

I see GIA has color as one of the lines of the report, is it not as “scientific” as color in the AGL report?

 

[T L]

I see GIA has color as one of the lines of the report, is it not as “scientific” as color in the AGL report?

I believe it just states hue, no mention of saturation or tone. Those attributes are saved for their evaluation of FCD’s.

 

[clumberlove]

LIBS doesn’t catch all elementary particles. The LA-ICP-MS is more accurate. Sometimes they can catch diffusion or rule it out with standard equipment.

I think LIBS can theoretically detect all elementary particles if correctly set up. The detection limits are considerably higher than LA-ICP-MS, can be a thousand-fold greater, 30 ppm, vs 30 ppb. If the element is at low concentration it could be missed even if the instrument is set-up correctly to detect it.

I would love to play with an LA-ICP-MS, we only have an ICP-OES at work, which isn't as fun as a laser! Limited to liquid samples, although we use it for a rather different application, so I doubt I can persuade the boss that we need one

 

[icy_jade]

Back to @Probee...

It’s a cabochon star ruby... no need to evaluate cut etc. GIA is much cheaper. So yeah I’ll go with GIA for your stone. It is comparing GIA ID for $85 to AGL ID for $160 right?

Origin is typically used (at least by vendors/sellers) when the stone is from a desired location. Eg
- Burmese almost any stone
- Sri Lanka sapphires
- Brazilian paraiba
- Mahenge spinel
- Colombian emerald
Reason being that the origin drives up the price.

In your case I think the origin probably isn’t so critical (no premium for a Viet star ruby) so the basic test would do.

Anyway if you want to spend more on AGL that’s fine too. Pls come back and let us know what your stone tested as ok?

 

[ChaiK]

I only have Nanyang Labs and GIA certs for my jadeite.

If yours is a ruby, GIA is good.

 

[ChaiK]

Oh wait. I forgot. And a few HK Jade Lab certs. The one @prs mentioned.

Anyway. Ruby GIA. Save money.