Paul on AGS New Cut-Grading of Princesses

[pricescope]

Paul Slegers (aka Paul-Antwerp) Shared his first experience with AGS'' new cut-grading of princesses


Paul outlines traditional approach to princess-shaped diamonds and major differences, its effect on cutting and pricing.


Great stuff.


My first question was whether one can see any of new AGS-0 princesses. Can someone post DiamCalc model?


Where we can see the requirements (proportions, angles, percentages, ranges)?

 

[strmrdr]

hmmm at 2x as much they are going to price themselves out of the market.
A quick look at the PS search results shows that Super-ideal rounds are only about 1.5 times a princess for the same weight/clarity/color.

 

[Paul-Antwerp]

Which basically only shows that currently super-ideal rounds are undervalued, and current princess-cuts are overpriced.

Live long,

 

[valeria101]

Date: 1/26/2005 8:311 AM
Author: strmrdr
hmmm at 2x as much they are going to price themselves out of the market.
A quick look at the PS search results shows that Super-ideal rounds are only about 1.5 times a princess for the same weight/clarity/color.

Yeah... but those are rounds, not square ! And shape shows enough to generate strong preferences. Branded fancies go along with branded H&A for price - and that''s pretty high up from where generic princess cuts stand now. If the new stats are that revolutionary, this may mean that there will ever be just a few AGS0 princesses, something not bad for a branded cut.

Now, as far as I remember, AGS worked with a certain version of the princess cut - is the standrad to be applied to all types after all ? If not, then there remains room for the argument that some different facet pattern than what AGS talks about makes some version of generic (or not) princess cut as effective as AGS0 squares but without the waste and premium. There are contenders to that already (generic princesses with three pavilion breacks and branded versions with 80 and 100 facets).

How about the princess cuts by Superbcet ? Those seem to fit AGS0 (at least they have small tables), although their stock has never been large.

As far as I know, AGS has released the stats of the princess cut grade, only not for public use. Jonathan has them (mentioned on an old thred)... but the consensus at the time was that these should not be put on public display against AGS''s instructions

Anyway...

Congratulation to the Pricescope Journal

It has been growing faster than I would have hoped

 

[strmrdr]

Date: 1/26/2005 8:40:10 AM
Author: Paul-Antwerp
Which basically only shows that currently super-ideal rounds are undervalued, and current princess-cuts are overpriced.


Live long,

imho they are all overpriced but thats an issue for another day and another thread.

Thank you Paul for the article my comments are in no way ment to take away from you being kind enough to take the time to write the article for us to study.

 

[belle]

paul, thank you for taking the time to share this information....for those of us who would like to think that a nice diamond can be square, this is a real step forward.

 

[moosewendy]

Paul - if the AGS "ideal" princess uses sharp crystal rough as inefficiently as you say, isn''t it likely that those stones will be cut from rough which is more suitable, thus improving the yield somewhat (though limiting the supply)? An analogous situation exists with the princess and the radiant. Since the traditional princess uses sharp crystals much more efficiently than radiants, radiants are not generally cut from "princess" rough. Instead, it is cut from that relatively small selection of rough which makes sense to cut into radiants. As a result, well cut radiants are far scarcer than princesses, but the price difference is far less than one would predict by analyzing yield differentials from the same rough. In my opinion, it is far more likely that "ideal" princesses will be be cut only from rough which delivers a far better yield than you project, and trade at a far lower price (maybe a 25% premium). Since, like the "ideal" princess, well made radiants have a fuller crown and flatter pavilion, the "ideal" princess will likely compete for rough more with radiants than standard princesses, and deliver yield similar to a well made radiant.

 

[Paul-Antwerp]

You have a point there, Wendy. Of course, with some rough being more suitable for a certain cut, there is an incentive in using this more.

Although, you should be aware of this situation: if you now buy a princess-cut, chances are very high that you are buying an AGS-5 or lower. If you are into a currently well-cut princess-cut, you are probably considering an AGS-3, which is definitely a lot better than an AGS-5.

Now, take this comparison to rounds. And think about new AGS-grades, which are really tied to light performance, unlike the current AGS-grades.

How much would you be willing to pay for a round AGS-5? How much more for an AGS-3? Remember, an AGS-3 translates into ''Good'' only. And what are the respective premiums for AGS-2 (Very Good), AGS-1 (Excellent) and AGS-0 (Ideal)?

I believe that, if consumers become aware of these grade-differences, the average cut-quality of princesses will go up (thus reducing the price of a cut similar to the current average), and the premium of an AGS-0 to the new average cut-quality will become less. Basically, what happened with rounds over the last 15 years will probably happen with princesses in the course of a year.

Live long,

 

[moosewendy]

Paul - I think you might be overestimating the influence of the AGS. The AGS 000 round reinforced an existing industry standard. The princess cut grade would impose a new standard on an industry notoriously resistant to change, with no particular interest in being forced to dramatically improve cut quality in princesses. I don''t think any lab other than the GIA has the clout to influence the industry the way you describe. I suspect the AGS 0 princess will be one of many "brands" on the market, and top notch marketing of the type done by HOF will be necessary to bring the prices you describe.

 

[denverappraiser]

Paul,

With well formed octahedral crystals, shouldn’t the stone be sawn slightly to one side of center anyway? It seems like this would yield a large stone and a smaller one instead of 2 that are relatively similar in size. The larger of these stones would already effectively have a crown on it thereby improving the yield even more. With the way diamonds are priced, a 1.50ct and a 0.50 stone is a significantly better result than two at 1.00 each. Wouldn’t this mean that a high crown with tiny table is no problem if that were what people wanted (at least on the larger stone)?

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

 

[moosewendy]

Neil, I think Paul''s point was that the big yield advantage gained from a standard princess is precisely that the stone can be sawn through the middle instead of the way you describe. By sawing down the middle, a standard princess manufacturer can get 2 carat stones. This will not be possible with the "ideal" princess, thus making the stones much more expensive to cut,

 

[denverappraiser]

Windy,

A perfect octahedron with one point cut off looks a lot like a princess with a tall crown and a tiny table. I'm sure Paul is right, I'm just not understanding where I'm wrong.

Neil

 

[moosewendy]

You''re absolutely right with every diamond cut other than the standard princess. The beauty of the princess from a manufacturing standpoint is that it follows the outline of a rough crystal so perfectly. The flat crown allows you to get away with sawing through the middle to get 2 more or less equal size stones. I don''t know of any other diamond cut which allows you to do this and still have a decently looking stone. It is this manufacturing edge which accounts for the flood of princesses on the market - not the inherent beauty of the stone.

 

[moosewendy]

Neil, you''re absolutely right that you would cut "ideal" princesses into a main stone and a smaller stone. Paul''s point is that this would negate the primary manufacturing advantage for cutting a princess in the first place, which is the ability to saw down the middle. Of course you can saw off center, it just costs a whole lot more to do.

 

[oldminer]

I think that regular princess cuts right now seem like a decent deal for cost conscious shoppers. Admittedly, these diamonds are not as high performing with light as fine rounds or finely cut princess cuts, but budget considerations are part of the decision making process.

Soon we will be able to directly measure light performance from princess cut diamonds. However they are fashioned, we will be able to make comparisons of performance with those that seem near the top of the game. I imagine that not all AGS ideal princess cuts will actually perform the same but certainly they all will be very lovely diamonds and stand head and shoulders above the average pricess cut in today's marketplace.

Cutters will be selective with rough, as they always are. Not every piece of rough that can cut a normal princess cut will also be economic to cut an Ideal princess cut. The reverse is probably true, too. There will be rough that lends itself better to the ideal cut than to the regular cut. It is a reshuffling of the cards. Once the best stones are identified, they will command premiums over less beautiful and less rare stones. Based on the actual cost of rough, how strong the market acceptance is, and the amount of promotion money spent, so goes the eventual market pricing...

It will be very exciting to see all this transpire.

 

[Garry H (Cut Nut)]

Well done yet again Paul.

Great communication - simple and clear.

Cutters sometimes saw thru the center, and sometimes thru the bishops hat method. It depends on the weights of the resultand stones and the total value. It maybe that a round and a princess are cut for example because of the position of inclusions. It is not as simple as this discusion has indicated.

Will AGS change the world?
Well actually it is DiamCalc and OctoNus that are changing the world. AGS used DiamCalc heavily for their study. Even the P1 and P2 terminolgy came from Diamcalc.
So the bigger question is will other labs take up the OctoNus approach?

The answer is like the GIA''s favorite phrase :watch this space".

 

[moosewendy]

Obviously, cutters decide how to saw each individual stone based on its unique characteristics.
It is simply far more economical to do it with a princess, so you always do it if you can. Nevertheless, the essential point is completely valid. Sawing a princess through the middle gives you a yield advantage unavailable in other shapes.


If the GIA adopts a cut grade for fancies, whatever technology they use, that will change the world. Without GIA endorsement, the world will remain more or less the same. All those class 5 princesses will continue to be cut and will continue to sell for prices based on the GIA certs, simply because the economics of diamond manufacturing compels it. Cutting "ideal" princesses in quantity will only make sense if enough people are actually willing to pay twice as much for them, as Paul proposes. If the AGS or Octonus want to change the world without the assistance of the credibility of the GIA brand, they will have to spend many millions of $$''s on effective PR to educate the public, and I doubt such an effort is forthcoming. Will the GIA adopt that technology for fancies? I guess we''ll find out. Until then, I suspect the world at large, in which far more crap sells than quality, will remain more or less the same.

 

[Garry H (Cut Nut)]

As someone with some skills in the field I am scratching my head and wondering what part of GIA''s approach could be of any use for fancy cut grading.
Other than looking at them and saying oh ah - that one is pretty.

 

[strmrdr]

Date: 1/26/2005 6:55:39 PM
Author: Garry H (Cut Nut)


Other than looking at them and saying oh ah - that one is pretty.

I cant resist this one:
Isnt that the most important test of all??

 

[Rank Amateur]

I can think of one vendor offhand whose princesses routinely have tables and pavillions under 60% and crowns over 12% (closer to 15%) but they are priced right along with other much more poorly cut princesses. They look good under the IS too - at least to this half-wit.

Has the AGS grading been published? I am curious as to where these stones fall and also how the AGS grading compares to the AGA grades. If memory serves, the smaller tables get knocked down a bit by Dave Atlas.

 

[valeria101]

Date: 1/26/2005 9:14:47 PM
Author: strmrdr

Date: 1/26/2005 6:55:39 PM
Author: Garry H (Cut Nut)

Other than looking at them and saying oh ah - that one is pretty.

I cant resist this one:
Isnt that the most important test of all??

Yes

as long as you have seen enough to know that some are prettier than others

... beyond the three bits one might be shown before a quick sale that is. Whatever they do, it''s nice to have some choice, no ?

 

[Garry H (Cut Nut)]

Date: 1/26/2005 9:14:47 PM
Author: strmrdr

Date: 1/26/2005 6:55:39 PM
Author: Garry H (Cut Nut)


Other than looking at them and saying oh ah - that one is pretty.

I cant resist this one:
Isnt that the most important test of all??

Hey Storm, lets do away with science and forget repeatability. Why not train some monkeys to make the grades up?

 

[valeria101]

Date: 1/27/2005 4:20:31 AM
Author: Garry H (Cut Nut)

Hey Storm, lets do away with science and forget repeatability. Why not train some monkeys to make the grades up?

' Bet they'd pick up the more brilliant stuff ! Not by numbers though...

Choosing gets random only when choices are not understood. Woudn't you agree ?

It definitely works with some other cut grading regnum - hope JCJD can chime in here

 

[strmrdr]

Date: 1/27/2005 4:20:31 AM
Author: Garry H (Cut Nut)

Date: 1/26/2005 9:14:47 PM

Author: strmrdr

Date: 1/26/2005 6:55:39 PM

Author: Garry H (Cut Nut)



Other than looking at them and saying oh ah - that one is pretty.

I cant resist this one:

Isnt that the most important test of all??

Hey Storm, lets do away with science and forget repeatability. Why not train some monkeys to make the grades up?

That would make a some jewelers very happy!
Is that really much different than what happens today other than its humans and not monkeys making up the grade?

Answer me this: What color is a G color diamond?
Answer - depends on who you ask.

Now back to my supposed to be funny but true comment.
Now Brian @ WF or Jonathon @ gog or R/T at niceice, even yourself or a few trusted others saying this sure is pretty is a pretty good test of a diamond. agree?
I wouldnt buy a diamond that any of the above said was ugly after them seeing it in person thats for sure.

Does it replace the rest of the info NO but it is an important part of the buying process.

The final test is if the new owner likes what they see when they get the diamond on the hand. Agree?

 

[oldminer]

Beauty is in the ey of the beholder. We can confer and decide upon "standards" but anyone is able to judge what is most beautiful to them and no one else might agree. If the given experts say a diamond is not pretty, it would be safe to say that nearly everyone would agree. When they say a diamond is beautiful, very few folks would disagree with them, either. It is the stones on the cusp, the ones that just about look super, but fail in some small way to be top performers. How much can the non-expert deiscern. Wheere does one draw the line? On these points we may never totally agree. Machines, experts, and novices will look to arbitrary expert "standards" that have artificially been created to make this decision. Hopefully, we can get past the point of G color being different depending on which lab one chooses. A higher standard would be desireable.

 

[moosewendy]

Would any of the diamond experts on here irrevocably commit to buy a fancy shape diamond, sight unseen, on the basis of measurements alone? Or would you insist on seeing the diamond before finalizing the purchase? If visual examination remains an indispensable element of evaluating cut, then isn''t an educated "looks beautiful," taking relevent proportion information into account, really still the only honest standard?

 

[oldminer]

MANY, Many better diamonds are bought on specs and sight unseen. Nearly all of this is between trusting, experienced parties, who know eachother pretty well. Should a consumer do the same? No.

 

[moosewendy]

David - if I trust someone else''s eyes, it''s the same as seeing it myself. The point is, it needs to be seen by someone who knows what to look for, not just measured by a machine. In my opinion, subjective human evaluation is too important a component in evaluating cut in a fancy to ever allow development of a meaningful machine generated cut grade.

 

[Garry H (Cut Nut)]

Date: 1/27/2005 10:59:21 AM
Author: moosewendy
Would any of the diamond experts on here irrevocably commit to buy a fancy shape diamond, sight unseen, on the basis of measurements alone? Or would you insist on seeing the diamond before finalizing the purchase? If visual examination remains an indispensable element of evaluating cut, then isn''t an educated ''looks beautiful,'' taking relevent proportion information into account, really still the only honest standard?

Yes - I do it based on a sarin scan which i can "see" in DiamCalc, even though the stone is overseas.

You will be bale to soo too here with Gem Adviser 3D files

 

[oldminer]

"The point is, it needs to be seen by someone who knows what to look for, not just measured by a machine. In my opinion, subjective human evaluation is too important a component in evaluating cut in a fancy to ever allow development of a meaningful machine generated cut grade"
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reply:

I agree that today someone expert needs to be the one seeing the stone. A machine might be able to give measures which help someone know more than at present. We just don''t know how well this communication may develop. We are not near that stage yet....so for now, this is not what anything, including machines do for us. Even when machines measure "beauty" not every last one of us will agree that it works for them. There will be some vocal opponents and traditionalists. No one will be forced into agreement. If the work is done well, then there will be very few people who don''t get it.

Please don''t doubt the possibility of truly meaningful fancy cut diamond grading. Don''t commit yourself to a position that some of us know is incorrect. It isn''t wrong to be skeptical and questioning, but if you had more complete understanding of where the process is right now, you would have no doubt that meaningful fancy cut grade communication is almost a done deal. It isn''t so much what machines can''t do,, but the difficult human aspect of deciding upon standards that make sense. There are things happening in this arena.