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The Differences in Appearance Within GIA Diamond Cut Grades

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pricescope

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GIA Newsroom: Thoughts From the President: The Differences in Appearance Within GIA Diamond Cut Grades

"...within each of these levels [grades], observers will often prefer one face-up appearance over another, but not necessarily the same one. That is, within each of the grade categories, there are a variety of appearances, with the single ''best'' diamond determined by personal taste, often in association with regional preferences."
 

stretch4

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I really like the three pictures of the "excellent" and "good" cut grades
1.gif
 

asblackrock

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Very interesting. Categories appear very broad.

In their first example of "good" they list pav angle as 49.4!!!!!!!!!
6.gif
Misprint? (39.4?)
 

Stephan

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Date: 4/16/2005 2:31:55 AM
Author: Garry H (Cut Nut)
There is a discussion about this in the Journal section off the PS front page.

Sorry, can't find it!
Can you post a link?



U_15363.gif

This diamond scores in the "Excellent" category.

Table size: 61.0%
Crown angle: 34.5°
Pavilion angle: 40.8°
Star length: 55.0%
Lower-girdle length: 80.0%
Could someone post a .gem file?
I'm very curious!
 

Regular Guy

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I notice two things, and will ask about a related third:

1) Their statement: "We know that, above all, a successful diamond cut grading system should boost consumer confidence in the purchasing decision...." is consistent with the intent reviewed in your survey not long ago, Leonid. Although the question certainly could have been asked...why so long...probably within the industry, because of both AGS and Pricescope among others, their jeweler clients have complained about unhappy customers without consumer confidence, and so this change seems a logical, and natural evolutionary development from them...presented with language that even still embodies what has been their reluctance to have brought this system forward...which is a sensitivity to differences in taste...perhaps, along with a desire to not have to blow a sale on behalf on behalf of one of its jeweler clients.

2) Also, I know that in what will perhaps now be standard in its presentation of "data" concerning a diamond, we see:

Table size: 61%
Crown angle: 34.5°
Pavilion angle: 40.8°
Star length: 55%
Lower-girdle length: 80%

Those guys in the know here talk about such things as star length & lower girdle length, in ways I have not yet found common parlance. Perhaps I am to understand the reporting of this info will now be as routine as what has been the reporting of depth info, along with table (and with depth perhaps now going out the window?)

3) Does anyone have any actual knowledge, or even an informed set of expectations, about how this will effect what both general and expert appraisers can and will do, going forward. Note the two groups, of which I consider the 4-5 appraisers consistently on this board in the expert class.

a) For example, regarding the experts..does the technology you employ allow you to measure star length and lower girdle length. Going further, and stretching back to a thread involving Paul, Garry, and Richard, where Paul suggested future non-AGS certed stones might have to only be shipped back to AGS for their imprimatur for any real consumer satisfaction on the subject...any substantive reply to the claim?

b) Moreover..for all those appraisers, who -- while AGS has been fairly widely used up to now, and perhaps by a group of buyers who might even more readily seek the services of an appraiser over the GIA certed buyers -- most appraisers up to now have not sought to verify any cut info, that I am aware of. Do you see your GIA trained appraiser come 1996 start to be able to perform analysis on a diamond's cut that they do not do at this time? Is the answer to this just obvious, or is it clear, based on training you know people in the pipeline now are receiving?

Leonid, and all, thanks for this update!
 

valeria101

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The presentation doesn''t allow to see any shortcomming of the grades... the whole thing appears to be a reasonable exercise.
It is hard to miss their attention to optical symmetry ("even pattern of light and darkness" - they say) - something the old GIA grades did not adress.

Above all, the pictures are stryking ! Somehow, they''ve managed to show both technical detail and three-dimentional feel of the diamonds. Judging those against commercial presentations elsewhere there seems to be some substantial difference - and much of it favors GIA''s approach.
 

Maxine

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Are these new grades being assigned based on certain #s, or appearance? How will the prices differ for each grade???
 

Paul-Antwerp

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Date: 4/16/2005 7:35:16 AM
Author: Regular Guy

a) For example, regarding the experts..does the technology you employ allow you to measure star length and lower girdle length. Going further, and stretching back to a threat involving Paul, Garry, and Richard, where Paul suggested future non-AGS certed stones might have to only be shipped back to AGS for their imprimatur for any real consumer satisfaction on the subject...any substantive reply to the claim?
There will be two major and fundamental differences in cut grading of GIA and AGS.

First, as you see, the top ''Excellent''-grade of GIA is still very broad. The result will be that GIA-Excellents will score in a range between AGS-0 down to AGS-2, and possibly even AGS-3. GIA claims that this difference is no longer a discernable difference in quality, but more a difference in taste. I beg to disagree, but I suppose that in the end, we will always have supporters for both points of view.

Secondly, there is a huge difference in grading approach. GIA is using averages of measurements, checking these (in a rounded form) in their charts (which are a result of their studies), and thus come up with a grade, entirely based upon average parameters. AGS, on the other hand, is taking a full 3D-scan of the stone (with a measurement of each individual facet) and will take this scan through their ray-tracing software. Stones with identical average parameters will get different grades by AGS, because of the differences of individual facets. This last approach allows AGS to also start cut grading for fancy shapes (princesses) now, whereas the GIA-approach will not end up in meaningful results for fancy shapes.

Live long,
 

Regular Guy

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I note one more thing, and reflect on the comments from the survey brought forward about a month ago...

While GIA could be criticized for taking a "bottom up" approach to scoring, saying....duh...we''re now just reporting on what people told us....in their comments on the good options vs the excellent ones, clearly, they present why they are only good, and not excellent...explicating the factors that they understand separate one from the other.

An overall hit...per Pauls comments, I gather AGS will be defining a tighter model for excellence. But, recognizing Garry''s purpose with this board, and a general intent to lift the standards widely, who can argue with what''s being done here?
 

Paul-Antwerp

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Date: 4/16/2005 8:27
6.gif
9 AM
Author: Regular Guy

An overall hit...per Pauls comments, I gather AGS will be defining a tighter model for excellence. But, recognizing Garry''s purpose with this board, and a general intent to lift the standards widely, who can argue with what''s being done here?
I think that you are hitting a very important subject, which leads me to the following question:

Of all the stones, currently going through GIA without a cut-grade, which percentage would get a grade of ''Very Good'' or ''Excellent'' in their upcoming system?

My estimate is around 80%, and I would welcome the estimate of others. If this is a correct estimate, then the new system will not contribute anything to the overall cut-quality available, unless the public will only want GIA-Excellent from now on, since ''Very Good'' means nothing more than ''just slightly below average''.

Live long,
 

oldminer

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The question of percventages in each category is thoght provoking. Newly cut diamonds can readily be cut to any set of "excellent" standards once they are published. There will be little economic reason to cut less than "excellent" in most cases. In the long run we wil have nearly all well cut diamonds simply because the knowledge of how to cut them will become widely known.

As far as existing inventory goes, I''d say there will be a mad rush to recut diamonds to the newest cut standards much in the way old cuts were recut to modern standards in past decades. Existing inventories and diamonds owned by the public are a huge source of recut work and will contain many not so well cut stones. I doubt we will see many cutters leaving them as is only to get a "good" grade on them.

"Excellent" cut will become one of the demands of consumers and of dealers. This is good for just about everyone who wants to have a diamond. Nearly everyone wants the prettiest stone they can afford.
 

strmrdr

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Id like to see side by side samples of the best excellent scoring diamonds with the lowest acceptable one for the same score.
The samples they posted all seem like they would be in the top end not the lower end of excellent.
 

strmrdr

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Date: 4/15/2005 7:27:50 PM
Author:Pricescope
GIA Newsroom: Thoughts From the President: The Differences in Appearance Within GIA Diamond Cut Grades


''...within each of these levels [grades], observers will often prefer one face-up appearance over another, but not necessarily the same one. That is, within each of the grade categories, there are a variety of appearances, with the single ''best'' diamond determined by personal taste, often in association with regional preferences.''
Like iv been preaching for a while...
The personality of a diamond makes a difference.
When you get into the top cuts its what sets them apart from one another.
Looks like gia agrees.
 

Paul-Antwerp

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Of the three examples of GIA-Excellent, according to the cutting guidelines of AGS,

number 1 would be AGS-1
number 2 would be AGS-0
number 3 would be borderline AGS 2 or 3

Live long,
 

Stephan

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Could someone post a .gem file for number 3?

Thank you!

 

Rhino

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Date: 4/15/2005 8:59:41 PM
Author: asblackrock
Very interesting. Categories appear very broad.

In their first example of ''good'' they list pav angle as 49.4!!!!!!!!!
6.gif
Misprint? (39.4?)
I caught that too Angela. I am 99% confident this is a typo on GIA''s part and would gamble in saying that that stones pavilion angle is 40.4 degrees instead of 49.4. ;-)
 

Rhino

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Date: 4/16/2005 6
6.gif
0
6.gif
5 AM
Author: QueenMum

Date: 4/16/2005 2:31:55 AM
Author: Garry H (Cut Nut)
There is a discussion about this in the Journal section off the PS front page.


Sorry, can''t find it!
Can you post a link?




U_15363.gif

This diamond scores in the ''Excellent'' category.


Table size: 61.0%
Crown angle: 34.5°
Pavilion angle: 40.8°
Star length: 55.0%
Lower-girdle length: 80.0%
Could someone post a .gem file?
I''m very curious!

Leo ... I love the fact that we can attach .gem files again. :) Here''s a .gem file on this one. DiamCalc uses lower girdle depth instead of length so I did my best to compensate.
 

Attachments

  • GIAEX01.gem
    1.4 KB · Views: 81

jigri2003

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Date: 4/16/2005 12:26:22 PM
Author: Paul-Antwerp
Of the three examples of GIA-Excellent, according to the cutting guidelines of AGS,

number 1 would be AGS-1
number 2 would be AGS-0
number 3 would be borderline AGS 2 or 3

Live long,
Paul,

Could you clarify how you are assigning the AGS grades to the GIA Excellent examples? Is there a thread or external article laying out the parameters for the new AGS system?

Also, I think you stated earlier that GIA''s grades are based on average measurements. From their cut grade FAQs on the GIA website:

"Why does the GIA System take the final grade from the attribute with the lowest value, instead of averaging the values of the different aspects of a diamond’s appearance?
Through observation testing, we found that each factor was important, not just the average of the several factors. So we arrived at a grading method that uses neither averaging nor “weighting”: instead, a diamond must score well in every aspect in order to get a high grade. This method produces results that most consistently agree with our results for overall appearance, and with the opinions learned from our extended interaction with the trade and consumers."


Am I reading this wrong to mean that they are taking the ''weakest link in the chain'' approach, as opposed to averaging?

Feedback from any of the manufacturers/dealers/vendors/appraisers on the board would be welcome. I''m one of those folks likely to need to buy before the new AGS & GIA cut grades are widely available, and would prefer to try and stay within the new Triple Zero and Excellent grades if possible. Of course, the best deal would be not current Triple Zero, but new Triple Zero! I think Paul stated in another thread that this would be a tough find, but hey, we''re all seekers here...
31.gif
 

AChiOAlumna

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I thought the new grading system was going to be applied to all cuts, but according to this article, it''s only being applied to RBs...am I missing something?
 

Michael_E

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Secondly, there is a huge difference in grading approach. GIA is using averages of measurements, checking these (in a rounded form) in their charts (which are a result of their studies), and thus come up with a grade, entirely based upon average parameters. AGS, on the other hand, is taking a full 3D-scan of the stone (with a measurement of each individual facet) and will take this scan through their ray-tracing software. Stones with identical average parameters will get different grades by AGS, because of the differences of individual facets. This last approach allows AGS to also start cut grading for fancy shapes (princesses) now, whereas the GIA-approach will not end up in meaningful results for fancy shapes.


Live long,

Paul,
The GIA is grading cut based on perceived beauty through numerous observations and different cultural biases. This would make their grading broad out of necessity and make the use of averages also a necessity. After all if one stone looks better to you and another looks better to me, who can make a judgement about the beauty of those stones and their cut quality ? Certainly not the AGS ray tracing system. Just because the AGS, (or anyone else), comes up with their own version of maximal beauty, that does not make it so for everyone. The other thing about the averages with the GIA system is that they will be grading symmetry as one of their criteria of excellence. If a group of facets is very far out of the symmetrical pattern of the rest of the stone, then it''s grade will be affected. I would think that this lack of symettry would be apparent and reduce the cut grade of the stone before it would affect the face up appearance of the stone. When you disdain the averaging of the GIA''s grading you may be looking at this with the precision of a cutters eyes and not with the way that these stones are viewed by most people. Most people, who are the end consumers of these stones, are looking at them in an "average" manner. They want something that is beautiful and really couldn''t care less if each facet is lined up within microns of being symmetrical with every other facet on the stone. They do care if an expert calls it "excellent", however. That''s really what this is about. Where do you get to hang the label,"excellent", since most people can''t tell the difference anyway. I suppose what it comes down to is, how close do you have to get to some hypothetical "ideal" to be called excellent, who decides what that "ideal" is and how can they possibly arrive at that "ideal" in a way that is easily commmunicated to the end buyer ? The AGS system is a pronouncement coming from a black box and is certainly not easy to explain, much less show a customer why one stone is a "0" and another is a "2", when the only thing that can see the difference is the black box.
Fancy shapes ? How fine can you split hairs ? Obviously there are lots of badly cut fancy shapes and quite a few good ones too. How would you define an ideal in any of them ? With software based on ray tracing or with numerous observations by the people who will be buying them ? I would imagine that fancy shape cut grading is something that the GIA will eventually apply even broader categories to, since everyone viewing them will have a different opinion.
 

Rhino

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Date: 4/16/2005 11:42:39 AM
Author: strmrdr
Id like to see side by side samples of the best excellent scoring diamonds with the lowest acceptable one for the same score.
The samples they posted all seem like they would be in the top end not the lower end of excellent.
I''m working on a table now which will include virtual models from each of the 5 classses of cut grades (3 examples from each grade) which we''ll be posting in our cut tutorial for people to compare to stones we''ve actually scanned in. I''ll give a heads up once I have this completed (shouldn''t take too long).
 

Rhino

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Hi RG,

In answer to your points/questions...


Date: 4/16/2005 7:35:16 AM
Author: Regular Guy
I notice two things, and will ask about a related third:

1) Their statement: ''We know that, above all, a successful diamond cut grading system should boost consumer confidence in the purchasing decision....'' is consistent with the intent reviewed in your survey not long ago, Leonid. Although the question certainly could have been asked...why so long...probably within the industry, because of both AGS and Pricescope among others, their jeweler clients have complained about unhappy customers without consumer confidence, and so this change seems a logical, and natural evolutionary development from them...presented with language that even still embodies what has been their reluctance to have brought this system forward...which is a sensitivity to differences in taste...perhaps, along with a desire to not have to blow a sale on behalf on behalf of one of its jeweler clients.
Well ... I can tell you that from within the trade there appears to be more whining and complaining than anything. I suspect that cutting factories are going to be taking one of 2 routes. They will either adjust their cutting practices to reflect the changes and *cut better goods* or they''ll abandon GIA and AGS altogether opting to not have this information on their reports. There are many factories already doing this for the simple reason that GIA and AGS are the most conservative in grading and they are looking for a more liberal grade in hopes of getting more money for their wares.


2) Also, I know that in what will perhaps now be standard in its presentation of ''data'' concerning a diamond, we see:

Table size: 61%
Crown angle: 34.5°
Pavilion angle: 40.8°
Star length: 55%
Lower-girdle length: 80%

Those guys in the know here talk about such things as star length & lower girdle length, in ways I have not yet found common parlance. Perhaps I am to understand the reporting of this info will now be as routine as what has been the reporting of depth info, along with table (and with depth perhaps now going out the window?)
I would imagine so. However it is my conviction that this info will only be provided by the labs giving this information. There are those of us within the trade who have the means wherewith to measure all these other facets and provide these details but most within the trade do not possess the hardware/software to determine this, so I would still think you will not find this lingo common parlance. While current cut grading systems do not take total depth % into account it is still a metric examined and avoided when it''s measurements fall too far to any extreme. In the new scheme I believe there is going to be a weight for size metric involved so stones cut too deep or too shallow will take hits.


3) Does anyone have any actual knowledge, or even an informed set of expectations, about how this will effect what both general and expert appraisers can and will do, going forward. Note the two groups, of which I consider the 4-5 appraisers consistently on this board in the expert class.
I can''t speak for other appraisers but I am sure they will be including this in their upcoming reports. I plan on incorporating both grading systems into our current appraisals and giving hte details for both or as much data as we can.


a) For example, regarding the experts..does the technology you employ allow you to measure star length and lower girdle length. Going further, and stretching back to a thread involving Paul, Garry, and Richard, where Paul suggested future non-AGS certed stones might have to only be shipped back to AGS for their imprimatur for any real consumer satisfaction on the subject...any substantive reply to the claim?
In answer to the first question yes. We have had custom reports made within our hardware/software setup that allows us to show and print all proportion measurements including star facet %, lower girdle facet %, lower girdle angles, & upper girdles angles. We have the plug-in on our minor facets tutorial. Regarding getting AGS new grades on currenlty graded stones ... I would imagine this could be assesed without necessarily sending it back to AGS. Since their grading will be based on an actual 3d model of the diamond, if a gemologist has the ability to generate those models himself I would imagine there will be software released by AGS which will allow the gemologist to get this information via their approved trace software.


b) Moreover..for all those appraisers, who -- while AGS has been fairly widely used up to now, and perhaps by a group of buyers who might even more readily seek the services of an appraiser over the GIA certed buyers -- most appraisers up to now have not sought to verify any cut info, that I am aware of. Do you see your GIA trained appraiser come 1996 start to be able to perform analysis on a diamond''s cut that they do not do at this time? Is the answer to this just obvious, or is it clear, based on training you know people in the pipeline now are receiving?
I think I can count on one hand the amount of appraisers who take these various characteristics into account. Most appraisres I know of either don''t give cut information at all or at the very most give a basic Sarin analysis. I hope to see more appraisers give the details that people are looking for. RockDoc, Dave Atlas, Rich Sherwood and Neil (Denveappraiser) are those rare finds that are keeping ahead of the times and offering optical examinations on diamonds which IMO is some of the most important information a person will garner before dropping the buckage.

Hope that helps.
 

Rhino

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Date: 4/16/2005 8:42:46 AM
Author: Paul-Antwerp

Date: 4/16/2005 8:27
6.gif
9 AM
Author: Regular Guy

An overall hit...per Pauls comments, I gather AGS will be defining a tighter model for excellence. But, recognizing Garry''s purpose with this board, and a general intent to lift the standards widely, who can argue with what''s being done here?
I think that you are hitting a very important subject, which leads me to the following question:

Of all the stones, currently going through GIA without a cut-grade, which percentage would get a grade of ''Very Good'' or ''Excellent'' in their upcoming system?

My estimate is around 80%, and I would welcome the estimate of others. If this is a correct estimate, then the new system will not contribute anything to the overall cut-quality available, unless the public will only want GIA-Excellent from now on, since ''Very Good'' means nothing more than ''just slightly below average''.

Live long,
80% getting very good or excellent grades? My are you optimistic!!!
emdgust.gif
This doesn''t say much for their grading system if you are indeed accurate.
 

Rhino

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Date: 4/16/2005 3:41:53 PM
Author: AChiOAlumna
I thought the new grading system was going to be applied to all cuts, but according to this article, it''s only being applied to RBs...am I missing something?
GIA will be rounds first, fancies later.

AGS will be princess cuts first, rounds 2nd, all others later. At least this is what I''ve been told.
 

Stephan

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Jonathan, once again, you are the one who did it!
Thank you for the .gem file!
(It looks great!)
 

Garry H (Cut Nut)

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¡§An overall hit...per Pauls comments, I gather AGS will be defining a tighter model for excellence. But, recognizing Garry's purpose with this board, and a general intent to lift the standards widely, who can argue with what's being done here?¡¨



Yes guy¡¦s, I am happy about any movement from GIA that reduces the supply of lousy cut diamonds. And we have already come a long way over the past 6 years already with larger certified diamonds ¡V and I think our group here on PS, OctoNus and MSU can claim some credit for that.
My staff have been monitoring the rejection rate on small stones lately. We selected $4k out of $20k of font>

Paul asked ¡§Of all the stones, currently going through GIA without a cut-grade, which percentage would get a grade of 'Very Good' or 'Excellent' in their upcoming system?¡¨
Pres. Bill Boyajian told manufacturers in India that the majority of diamonds they were submitting to GIA would be in the top 2 grades. I doubt that would be true of most of the Israeli goods I see however; many of those manufacturers seem to be producing mush the same cut quality that they were a decade ago.

AChiOAlumna ¡§I thought the new grading system was going to be applied to all cuts, but according to this article, it's only being applied to RBs...am I missing something?¡¨



This is a fundamental problem with gIA¡¦s approach ¡V they can only do round. A very senior guy on the program told me they have not even thought about how they will approach fancies yet.




Michael E.
¡§That's really what this is about. Where do you get to hang the label,"excellent", since most people can't tell the difference anyway. I suppose what it comes down to is, how close do you have to get to some hypothetical "ideal" to be called excellent, who decides what that "ideal" is and how can they possibly arrive at that "ideal" in a way that is easily commmunicated to the end buyer ?¡¨
I have often argued here on PS that super doper cut has gone too far ¡V but am constantly howled down by expert consumers who GIA should have put on their panel ƒº

Michael E.
¡§ The AGS system is a pronouncement coming from a black box and is certainly not easy to explain, much less show a customer why one stone is a "0" and another is a "2", when the only thing that can see the difference is the black box. ¡§ Michael ¡V the black box approach has certain benefits ¡V ie if it is up to scratch it works with any shape diamond
Michael E.
¡§Fancy shapes ? How fine can you split hairs ? Obviously there are lots of badly cut fancy shapes and quite a few good ones too. How would you define an ideal in any of them ? With software based on ray tracing or with numerous observations by the people who will be buying them ? I would imagine that fancy shape cut grading is something that the GIA will eventually apply even broader categories to, since everyone viewing them will have a different opinion. ¡§
We have begun to see that aGS¡¦s new approach will blow existing princess cuts out of the water!

Now if you are ready ¡V contemplate the next generation. A black box that works better than any other ¡V that can tell the cutter how to cut the most beautiful diamond of any shape ¡V even never before seen ¡V out of each and every piece of rough diamond. This is what the OctoNus Master Stone Study is all about. This will completely revolutionize diamonds and the industry.

Here is a link to my review of the GIA Foundation article http://journal.pricescope.com/Articles/6/1/A-review-of-the-%e2%80%9cfoundation%e2%80%9d-of-GIA%e2%80%99s-new-cut-grade-system.aspx

 

Paul-Antwerp

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Date: 4/16/2005 3:18:19 PM
Author: jigri2003


Paul,

Could you clarify how you are assigning the AGS grades to the GIA Excellent examples? Is there a thread or external article laying out the parameters for the new AGS system?

Also, I think you stated earlier that GIA''s grades are based on average measurements. From their cut grade FAQs on the GIA website:

''Why does the GIA System take the final grade from the attribute with the lowest value, instead of averaging the values of the different aspects of a diamond’s appearance?

Through observation testing, we found that each factor was important, not just the average of the several factors. So we arrived at a grading method that uses neither averaging nor “weighting”: instead, a diamond must score well in every aspect in order to get a high grade. This method produces results that most consistently agree with our results for overall appearance, and with the opinions learned from our extended interaction with the trade and consumers.''


Am I reading this wrong to mean that they are taking the ''weakest link in the chain'' approach, as opposed to averaging?
As an interested cutter, I have received the ''cutting guidelines'' for the new AGS-system. That is the basis used in order to estimate future AGS-grades for the 3 mentioned GIA-Excellents. This procedure is not 100% correct, but it gives an idea.

If I say that GIA is working with average measurements, I mean the following. If we are talking main pavilion angle, we have 8 facets like this, and GIA is using the average angle of these 8 facets. The same applies for the crown angle, and like-wise one has 16 lower girdle facets, 8 star facets and 4 table diameters.

Because GIA uses averages, this means that a stone with an average pavilion angle of 41.5, ranging from 41.1 to 41.9, and a stone with the same average angle of 41.5, with 5 facets of 41.5 and 3 of 41.4, will have the same GIA-grade.

Live long,
 

jigri2003

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8
As an interested cutter, I have received the ''cutting guidelines'' for the new AGS-system. That is the basis used in order to estimate future AGS-grades for the 3 mentioned GIA-Excellents. This procedure is not 100% correct, but it gives an idea.

Thanks for the follow-up, Paul. To a part of my original question, are these guidelines available somehow to consumers, or are they restricted to manufacturers for the time being?
 

Regular Guy

Ideal_Rock
Joined
Jul 6, 2004
Messages
5,960
Perhaps this is best addressed to Garry, but any informed opinion is more than welcome...

Regarding what portends to be the new format for data presented by GIA:

Table size: 54%
Crown angle: 34.0°
Pavilion angle: 40.8°
Star length: 50%
Lower-girdle length: 75%

Based on how the HCA has, up to now, been able to massage sarin data to arrive at a score that allows the consumer to make an informed narrowing of selections...can we anticipate that either an HCAII, or another such friendly utility, will allow those offerings certed by GIA in the future -- to be graded in a way that Paul will allow that GIA''s overly friendly grading can be reinterpreted, to one more valuable to the consumer.

Or, in other words, now that GIA will post numbers...although they''re missing some of the ones typically needed by HCA today....can we ignore their ratings for those large number of diamonds that will continue to be certified by GIA, and continue to seek to find value in those options, staying the smart consumers we''ve become accustomed to being on this board?
 
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