ags vs gia topic...again!

[astar11]

I've been to several jewellers, in different countries. Most of them know gia than ags. In the states, when i asked, which one is better?
They said gia.
According to truthaboutdiamonds.com; gia is better than ags. U§ jeweler pretty much got same reasoning as what stated on truthaboutdiamons.

And another thing f in ags, can mean g or h in gia. Is this true?
Opinion?

 

[Kelli]

I had a GIA triple ex diamond that was graded I vs2. After learning about diamonds here, I found out that the dark center I was seeing was leakage due to a less than stellar cut. It bothered me, so I sent it for a recut. After the recut it was graded an H vs2 by AGS. I figured either the part with more color was the part that got cut off during the recut, or that maybe AGS is a little softer on color grading. Either way, they have a much better cut grading (IMO) than GIA, and cut is what matters most to the beauty of a diamond.

 

[diamondloveaffair]

ags provides cut performance data. It can instantly tell you the degree of cut of a diamond with the platinum report far better than what a gia report would tell you. When you ask these jewelers about this question, do they carry "ideally cut" diamonds? More often than not, sellers holding inventory with "not so ideal" cut diamond will just say that AGS is a sham or not as good as GIA. When you look deeper and check out their inventory, you'll soon realize that how far their diamonds deviate from ideally cut stones even if they are GIA triple excellents.

 

[doberman]

I would run far and fast from any jeweler who said that GIA is better than AGS. Both are good, but AGS provides more info about cut than GIA. I am partial to AGS diamonds; I have two.

 

[hawk25]

There have been a few instances (I believe discussed on PS) where AGS graded one color grade higher than GIA, but that's trying to draw a conclusion from anecdotal evidence. It could have easily been due to an F color being a high F (borderline on G). Both labs are still issuing their opinion on color by human employees, and even the labs themselves say that there can be variations of one color grade.

I have a suspicion that many people (and perhaps even some jewelers) say GIA is better simply because their history and reputation. I've read through different forums where people insist on only buying GIA graded stones, which in itself is good consumer advice compared to letting people by EGL stones, but it ignores the equally reputable lab of AGS. Those consumers have therefore eliminated many good stones out of consideration.

This thread had a great discussion about the same topic:
https://www.pricescope.com/community/threads/agsl-vs-gia-in-color-clarity.189312/

 

[TC1987]

I don't know who or what is behind it, but this GIA Dossier vs. a full report on GIA-graded diamonds under 1ct is a real turnoff to me. I have always thought that the best-cut diamonds get sent to AGS (not saying that there are no comparable diamonds passed through GIA's labs.) But this nonsense of not being able to pull up a report that shows an inclusion plot is a real nuisance and it would sure be a deal-breaker for me. Is it meant to help cripple and kill Internet diamond sales, or what?

 

[bunnycat]

There have been a few instances (I believe discussed on PS) where AGS graded one color grade higher than GIA, but that's trying to draw a conclusion from anecdotal evidence. It could have easily been due to an F color being a high F (borderline on G). Both labs are still issuing their opinion on color by human employees, and even the labs themselves say that there can be variations of one color grade.

I have a suspicion that many people (and perhaps even some jewelers) say GIA is better simply because their history and reputation. I've read through different forums where people insist on only buying GIA graded stones, which in itself is good consumer advice compared to letting people by EGL stones, but it ignores the equally reputable lab of AGS. Those consumers have therefore eliminated many good stones out of consideration.

This thread had a great discussion about the same topic:
https://www.pricescope.com/community/threads/agsl-vs-gia-in-color-clarity.189312/

Thank you for posting that Hawk.

I would repost these quotes from John Pollard and also Kenny and underscore about 10 times....

We submit hundreds of diamonds to both labs. Furthermore, we spend weeks romancing each stone, whereas the lab graders have just a "dinner-date" with them. Consequently, I think we're in a strong position to grade the graders.

I find the agreement between AGSL and GIA's locations when it comes to color, clarity and finish to be eerily strong. If someone wants to say that AGSL's color masters have soft borders in some cases then it must be acknowledged that GIA's clarity thresholds are equally soft in other cases. Let us remember that every lab sets their own benchmarks, which is completely fair. And since the commonly accepted tolerance (per appraisers) when grading un-mounted diamonds is one grade either way I find AGSL and GIA results extremely in-sync...far more in-sync than that that acknowledged tolerance allows.

Since no one else has mentioned it, I feel I should mention that AGSL has only one location with a small team of gemologists. They are consistent with themselves... Meanwhile GIA has many worldwide locations with hundreds of grades issuing tens of thousands of reports per week. Logically (even unavoidably) there are inconsistencies between those locations. In fact, it's not unheard-of for a trader who didn't get the desired grade at one GIA lab to polish off the inscription(s) and send the diamond(s) to a more "friendly" location, hoping for a better outcome.

I'm suspicious that there is a process going on in which PS discussions solidifies things facts that are not facts.

I'll consider AGS and GIA equal till I see double blind scientific proof of a large set of data the proves otherwise.
Onezies Twozies and hearsay and repetition of, "what I heard" or "what I read" are not enough for me.

What happens on PS can be powerful, persuasive and frankly creepy at times.

I perceive AGS and much more pro-consumer and GIA as much more pro-industry.
GIA's huge loosie-goosie and industry-friendly "Excellent" cut grade includes those less-attractive, but more-profitable and weight-saving steep deeps.

When choosing between two diamonds, all other things being equal I'd support AGS by buying a stone graded by AGS over one graded by GIA.

 

[Dancing Fire]

I have had purchased both and don't mind buying either lab if I get all the information about the stone. color and clarity?...don't forget these are graded my human eyes. I'm sure there are stones that a grader will call SI1 today and the same grader might call it an VS2 tomorrow, and as for the color? ...same reason,b/c there are in between colors (high/low).the grader call it an H color today, but he/she may grade the same stone a G color next week.

 

[Niel]

Recently a guy came here looking for a 1.5-1.7 ct stone. He found a gia h, AGS h, and a gia I.


In regards to cut, the gemologist found the I to perform best.

In regards to color, the gemologist found no real observable tint in either gia diamonds but did in the AGS stone.


I know it was just one instance, but I found that interesting that the AGS didn't necessarily automatically have the best cut, and that the gia I had less tint than the AGS h.

Here's the thread.

[URL='https://www.pricescope.com/community/threads/search-for-best-14-16k-round-diamond-on-james-allen.189377/']https://www.pricescope.com/community/threads/search-for-best-14-16k-round-diamond-on-james-allen.189377/[/URL]

 

[denverappraiser]

What makes GIA the best is that they are the best known lab going, by a lot. They are the definition of the various grades and the definition of what is ‘correct’ in terms of clarity and color. All others are estimating what GIA would be expected to call it and GIA is reporting what they DID call it. That’s a lot.

What makes AGS the best is their cut grading system. It’s the only reasonably transparent, peer reviewed system out there based on real science. It’s the only one that even tries for shapes other than modern round brilliant. Where the GIA scale is deliberately set to be industry friendly and grades a broad swath of stones as ‘excellent’, AGS shows a far narrower focus on what is and is not an AGS-0.

Which is better for you depends on your objectives. Buying stones sight unseen and basing your decision purely on the grading report, you know more about what you’ll get from an AGSL report. To me that’s a big deal. It’s less so to others. A pursuit of minimizing perceived risk will lead you to GIA. A GIA-G is a G because, well, that’s the definition of G. An AGS-G will probably be a G because they seem to be consistent in their grading but that’s not the same thing. Grading is done by humans after all. On the other hand, an AGS-0 will be ‘ideal’ because THEY are the definition of idealness. A GIA-excellent might fit into ideal as well, but a fair fraction will not and GIA mostly doesn’t care. They have a much broader definition of what constitutes a top grade stone and disagree with the whole concept of narrowing it down from there. The lab started in the 30’s and they didn’t provide any sort of cut grade AT ALL until 2006. What they ended up with is a compromise between consumer pressure for a grade that they can use as a shopping tool and industry pressure for a scale that results in sales of lots of stones, not just the top 1%. Their argument, which is not without merit, is that beauty is a famously difficult concept to pin down and given that the purpose of cutting is supposedly to maximize beauty, there is a wide margin to accommodate varying tastes. AGS isn’t trying to quantify beauty. They’ve internally defined ‘light performance’ and are mathematically deciding stones that score as high as possible against that standard. That’s not the same as answering which one is the most beautiful, sparkly, fiery, or whatever but it is a far more solid metric for scientific types of customers than the GIA approach of interviewing observers about what they like the best and statistically churning out what proportions seem to be popular with the crowd.

 

[Rockdiamond]

I don't know who or what is behind it, but this GIA Dossier vs. a full report on GIA-graded diamonds under 1ct is a real turnoff to me. I have always thought that the best-cut diamonds get sent to AGS (not saying that there are no comparable diamonds passed through GIA's labs.) But this nonsense of not being able to pull up a report that shows an inclusion plot is a real nuisance and it would sure be a deal-breaker for me. Is it meant to help cripple and kill Internet diamond sales, or what?

Interesting point TC- thanks for sharing.
I love the Dossiers- for one main reason- they cost less.
Not trying to be cheap, but when you're submitting hundreds of stones it makes a huge difference.
even for a consumer buying a diamond less than $2k- it makes a difference in price.
Plus, the Dossier adds value by including the inscription.
Another factor: Clarity plotting is not all that useful in figuring out how a diamond looks in real life.
But I see your point about missing the plot. I don't think it's meant to hurt online sales- a case could be made that the opposite it true.

Great points made by Kenny about how using a small sample size gets turned into "fact" in online discussions.

From my perspective, both labs are excellent.
I totally get Neil's point and have found that to be a weakness of GIA- they're just too big to sometimes get the best service. But they're trying ( very

No matter good AGSL is, and they are- it still becomes a moot point when discussing fancy shapes, and or fancy colors.
In those arenas, GIA has no competition.

 

[Christina...]

What makes GIA the best is that they are the best known lab going, by a lot. They are the definition of the various grades and the definition of what is ‘correct’ in terms of clarity and color. All others are estimating what GIA would be expected to call it and GIA is reporting what they DID call it. That’s a lot.

What makes AGS the best is their cut grading system. It’s the only reasonably transparent, peer reviewed system out there based on real science. It’s the only one that even tries for shapes other than modern round brilliant. Where the GIA scale is deliberately set to be industry friendly and grades a broad swath of stones as ‘excellent’, AGS shows a far narrower focus on what is and is not an AGS-0.

Which is better for you depends on your objectives. Buying stones sight unseen and basing your decision purely on the grading report, you know more about what you’ll get from an AGSL report. To me that’s a big deal. It’s less so to others. A pursuit of minimizing perceived risk will lead you to GIA. A GIA-G is a G because, well, that’s the definition of G. An AGS-G will probably be a G because they seem to be consistent in their grading but that’s not the same thing. Grading is done by humans after all. On the other hand, an AGS-0 will be ‘ideal’ because THEY are the definition of idealness. A GIA-excellent might fit into ideal as well, but a fair fraction will not and GIA mostly doesn’t care. They have a much broader definition of what constitutes a top grade stone and disagree with the whole concept of narrowing it down from there. The lab started in the 30’s and they didn’t provide any sort of cut grade AT ALL until 2006. What they ended up with is a compromise between consumer pressure for a grade that they can use as a shopping tool and industry pressure for a scale that results in sales of lots of stones, not just the top 1%. Their argument, which is not without merit, is that beauty is a famously difficult concept to pin down and given that the purpose of cutting is supposedly to maximize beauty, there is a wide margin to accommodate varying tastes. AGS isn’t trying to quantify beauty. They’ve internally defined ‘light performance’ and are mathematically deciding stones that score as high as possible against that standard. That’s not the same as answering which one is the most beautiful, sparkly, fiery, or whatever but it is a far more solid metric for scientific types of customers than the GIA approach of interviewing observers about what they like the best and statistically churning out what proportions seem to be popular.

This is an excellent post and I completely agree!

 

[denverappraiser]

No matter good AGSL is, and they are- it still becomes a moot point when discussing fancy shapes, and or fancy colors.
In those arenas, GIA has no competition.

I don't know, the AGS princess rules are pretty good and the AGS-0 princesses are consistently lovely. Actually, I'm quite fond of the AGS oval's as well and I think they're a sleeper category in the industry but that's been such a commercial bust that you'd be hard to buy one if you wanted one. For shoppers it's purely an academic question. My understanding is that they're just too hard to cut and the cutters don't want to bother because there's just not enough demand. It's a chicken/egg sort of problem. Most people, including most in the trade, have never even seen one so they don't ask for them. Cutters don't want to waste their time and resources producing something that has little demand so they don't produce them. Consumers don't even know they exist.

 

[JulieN]

I've yet to see an AGS light performance graded oval on the PS database.

 

[Rockdiamond]

Interesting point about princess cuts Neil.
If you look at statistics, Princess is supposed to be number 2 behind rounds in terms of popularity.
If you look at forums like PS- and my own experience, they're not requested all that much compared to rounds- or cushions.
As far as the AGS standards for them-a case could be made that of the princess cut shoppers there are, many will choose a traditional stone over the AGS0 princess cuts for reasons of appearance
If course this is taste based, but from my perspective, and what I see in the market, the AGS cut grading for princess cuts has nowhere near the appeal of their round cut grading.

 

[denverappraiser]

I agree, AGS princess has nothing like the market recognition of their rounds. Ovals and emerald cuts are so little as to be irrelevant. Specialty cuts, like the GOG antique cushions, the Ritani thingies and other branded cuts are joint promotions with particular dealers and although I’m sure they each do just fine in their own niche, they don’t really affect the broader market.

Unfortunately, I think people are getting less and less imaginative when it comes to diamonds. The market share of modern round brilliants seems to grow every year. I don't have stats on this although I do think I've seen them somewhere but it's a shame. Cushions are definitely on the rise and they're taking market from princesses, not rounds.

We don't know but I'm guessing the OP is talking about rounds. Most people are. Astar11, are you still out reading?

 

[TC1987]

Responding to:

Interesting point TC- thanks for sharing. ...

Sorry, but this new math makes me uneasy, and I can't be the only one feeling that way. A .25ct or .33ct I might let slide, but .7-.99 is not an insignificant purchase.

Dossiers cost less - I can understand that one, lol.

even for a consumer buying a diamond less than $2k- it makes a difference in price - I personally won't buy anything online on just a Dossier, unless you want to sell it to me at a pawn shop price. The vendor will have to provide a complete report. It's not adequate to me to say "There are X, Y, and Z inclusions in this stone, but we are not going to show you exactly what, or where they are located." I will accept nothing less than all of the terms of sale and claims and specifications in writing. It just seems absurd to me to stop providing the the superb online documentation that Internet buyers have come to accept as the standard based on 10 years of history.

Dossier adds value by including the inscription --- Diamonds are identified by their inclusions. Inscribe it Eat More Tacos or BR549 or leave it plain, but I still want to know what inclusions, how many, and where.

Clarity plotting is not all that useful in figuring out how a diamond looks in real life. -- Oh, I'd still look at it, but I won't excuse a seller from providing complete documentation, unless the price is very reduced.

Sorry, but it's been annoying to click the report link and see just a GIA Dossier because we can't look at a plot and say "Ask about _______, and determine if ________, or avoid that diamond for a ring b/c of __________."

 

[Rockdiamond]

That's one of the great things about the way the internet has given shoppers more choices.
Some people won't buy a diamond without a laser inscription, others want to see a plot.
I agree that there's upsides and downsides to both- and neither, on it's own, is conclusive when one needs to identify a diamond.
Thankfully there's all kinds of sellers offering consumers a wide array of representation and offerings.
By all means, stick to what you're comfortable with!

 

[astar11]

I agree, AGS princess has nothing like the market recognition of their rounds. Ovals and emerald cuts are so little as to be irrelevant. Specialty cuts, like the GOG antique cushions, the Ritani thingies and other branded cuts are joint promotions with particular dealers and although I’m sure they each do just fine in their own niche, they don’t really affect the broader market.

Unfortunately, I think people are getting less and less imaginative when it comes to diamonds. The market share of modern round brilliants seems to grow every year. I don't have stats on this although I do think I've seen them somewhere but it's a shame. Cushions are definitely on the rise and they're taking market from princesses, not rounds.

We don't know but I'm guessing the OP is talking about rounds. Most people are. Astar11, are you still out reading?

Yes i am talking about round

 

[marcy]

Very interesting discussion. I've had 2 AGS0 and one GIA EX. Based on the ones I've owned and compared in the store the AGS0 were better performing diamonds. The GIA EX I owned always seemed to have a dead spot or two. I traded it in within 4 months of purchase.

 

[DelsFan]

What makes GIA the best is that they are the best known lab going, by a lot. They are the definition of the various grades and the definition of what is ‘correct’ in terms of clarity and color. All others are estimating what GIA would be expected to call it and GIA is reporting what they DID call it. That’s a lot.

What makes AGS the best is their cut grading system. It’s the only reasonably transparent, peer reviewed system out there based on real science. It’s the only one that even tries for shapes other than modern round brilliant. Where the GIA scale is deliberately set to be industry friendly and grades a broad swath of stones as ‘excellent’, AGS shows a far narrower focus on what is and is not an AGS-0.

Which is better for you depends on your objectives. Buying stones sight unseen and basing your decision purely on the grading report, you know more about what you’ll get from an AGSL report. To me that’s a big deal. It’s less so to others. A pursuit of minimizing perceived risk will lead you to GIA. A GIA-G is a G because, well, that’s the definition of G. An AGS-G will probably be a G because they seem to be consistent in their grading but that’s not the same thing. Grading is done by humans after all. On the other hand, an AGS-0 will be ‘ideal’ because THEY are the definition of idealness. A GIA-excellent might fit into ideal as well, but a fair fraction will not and GIA mostly doesn’t care. They have a much broader definition of what constitutes a top grade stone and disagree with the whole concept of narrowing it down from there. The lab started in the 30’s and they didn’t provide any sort of cut grade AT ALL until 2006. What they ended up with is a compromise between consumer pressure for a grade that they can use as a shopping tool and industry pressure for a scale that results in sales of lots of stones, not just the top 1%. Their argument, which is not without merit, is that beauty is a famously difficult concept to pin down and given that the purpose of cutting is supposedly to maximize beauty, there is a wide margin to accommodate varying tastes. AGS isn’t trying to quantify beauty. They’ve internally defined ‘light performance’ and are mathematically deciding stones that score as high as possible against that standard. That’s not the same as answering which one is the most beautiful, sparkly, fiery, or whatever but it is a far more solid metric for scientific types of customers than the GIA approach of interviewing observers about what they like the best and statistically churning out what proportions seem to be popular with the crowd.

Neil, thank you for such a clear and concise opinion. As a consumer I (and most other readers here) represent a small part of the diamond market (or any other market: cars, clothes, tires, or even food). Most US consumers cannot be bothered to know or care; I (we) am looking for the most beautiful diamonds from a group from which any would outshine the vast majority of diamonds sold now in the US. (Am I the only one who walks by the (well-know brand of) jewelry store in the mall and says to himself, "It's really too bad that someone hit that diamond over the head with a hammer before mounting it in that setting."?)

As a consumer, I am looking to buy a diamond (or five, or twelve) that looks great. I am not looking to re-sell it, so in my case having the (GIA) appraisal that is more recognized is of less value to me. Having a diamond that looks better than 99% of the other diamonds out there is the priority. If I end up with an ACA or other "super" ideal cut AGS000 E VS1 stone and want to sell it later, I expect not having a GIA certificate wouldn't be a problem. I mean, if I were looking at a used stone like the one described above how bad could it be? I would see that it is AGS000 and could most likely see idealscope and asat images. And I would know it was branded as "superior" by a vendor that I had heard of here on PS. At worst this AGS000 E-VS1 stone would be a super good looking F color stone. While a GIA 3X E-VS1 stone would probably really be an E-color stone, I'd have no idea if the cut (and look of the stone) was great or (amongst other fairly well cut stones) very average. REALLY, what I know about a GIA 3X stone with an HCA around 2 is it is not terrible looking.

I've talked to two vendors, one from each camp. The (well-respected) vendor with the GIA stones says look, I have a lot of experience, we'll get some GIA 3X stones in (that already have an HCA of around 2, thereby weeding out the majority of average looking GIA 3X stones) and look at the stones through the ideal scope and go from there. This guy has been doing this for many years, he knows a great looking stone from a good one, and I trust his judgement as well as his integrity. I trust this guy, and if I go this way I have a comfort level that I'll be getting great looking stones. With the AGS "super" ideal cut stones I probably also know I'm getting a superior looking stone, and I know I am paying for it too!

There is no free lunch, the only thing most of us very particular consumers are afraid of is paying a premium for a product while not really getting the premium product. It is sometimes important to save money (don't spend too much time here at PS!) but don't we all hate getting a pile of money together to make a fabulous purchase and then having to wonder if we are getting what we are paying for!

Neil, thanks again for your insight...