Princess Cut Ideal Cut

[avengerzx9]

All,

I''ve been using the Princess Cut Chart provided by PriceScope to grade the different diamonds I''ve been seeing from different local vendors. I''ve been approach by a vendor today that told me that the princess cut diamond I''ve been looking at falls into the "Ideal Cut" parameter, but it doesn''t match those on the Princess Cut Chart on Pricescope.

This is the parameter of the diamond

F-VS1 EX Polish VG Symmetry 71.6% Depth 73% Table.

While the Depth is okay, the Table % falls out of the range for both Ideal and Premium cut. So am I looking at the data incorrectly?

Lastly, I read on GoldOldGold that "Our very first step to finding the best princess cuts is to NOT waste any time with stones that have tables that are larger or greater than their total depths"

Is that true? Is the depth and table they talk about the % I''ve provided above?

I am a newbie when it comes to diamond, please assist.

Thanks

T

 

[Rhino]

Hi avenger,

Just some comments based on my experience.

Date: 12/16/2008 10:07:01 PM
Author:avengerzx9
All,

I''ve been using the Princess Cut Chart provided by PriceScope to grade the different diamonds I''ve been seeing from different local vendors. I''ve been approach by a vendor today that told me that the princess cut diamond I''ve been looking at falls into the ''Ideal Cut'' parameter, but it doesn''t match those on the Princess Cut Chart on Pricescope.

Firstly while I haven''t seen the PriceScope charts lately I can tell you (and no disrespect to anyone who attempts to help others with numerical charts etc.) but most of these numerical charts are worthless when it comes to fancy shapes and especially princess cuts. At the very least 2 sets of crown angles and 2 sets of pavilion angles as well as table and total depth are necessary before a prediction can even be attempted. The best charts I''ve seen are from AGS but even those of us who have seen many AGS Ideals would concur that their grading sysytem for princess cuts, while the best out there is still liberal. For a princess cut to *truly* be "Ideal" it must be graded by AGS Laboratories. If you are being told a Princess cut is in fact an Ideal Cut and is not graded by AGS you are being fed a line of kaka.

No disrespect to the PriceScope chart either but if it isn''t following AGS guidelines then it is a prediction and most likely a bogus one.

Now it is possible to determine AGS Ideal Light Performance but one must possess the necessary hardware and AGS'' proprietary ray tracing software to make these determinations. If they do not they are simply blowing steam.

This is the parameter of the diamond

F-VS1 EX Polish VG Symmetry 71.6% Depth 73% Table.

While the Depth is okay, the Table % falls out of the range for both Ideal and Premium cut. So am I looking at the data incorrectly?

No and even if you were those AGS Ideal''s with tables =>70 in my experience have not been the best of the AGS Ideals.

Lastly, I read on GoldOldGold that ''Our very first step to finding the best princess cuts is to NOT waste any time with stones that have tables that are larger or greater than their total depths''

Is that true?

Yep. I had written this statement before AGS even came out with their system. After they did it only proved my comment correct as most AGS Ideals do indeed have tables that are less than their total depths. I was also careful to say that this was not a hard fast rule too as there are some (albeit few) that look ok. If a company is claiming "Ideal" anything I''d throw out the challenge ... prove it. Otherwise I wouldn''t believe it. Whether its $500 or $50,000 its your hard earned money and when it comes to diamonds I''m not a gambling man.

Peace,

 

[avengerzx9]

Thank you Rhino,

If I can get the 2 sets of crown angles and 2 sets of pavilion angles, what would be a good combination?

Thanks

T

 

[JulieN]

Get the pictures. Very few machines capable of correctly measuring the angles.

 

[Lorelei]

" Whether its $500 or $50,000 its your hard earned money and when it comes to diamonds I''m not a gambling man."

Excellent food for thought Jon and a good reminder that one should not assume anything.

Avenger as Jules says, get the pictures if you can.

 

[stone-cold11]

There is none, as mentioned before. Get images, preferably ASET.

 

[Paul-Antwerp]

I fully agree with Rhino.

If a vendor claims a fancy shape to be Ideal, he should be capable of offering some real proof. Unfortunately, not many can.

And the PS-charts for fancy shapes are basically an attempt to offer some guidance on incomplete information. Using them offers no guarantee, not to surely exclude a bad stone, and definitely not to select a great stone. And with the relatively new AGS-knowledge, the charts are outdated, since they are based upon observation of stones, prior to the new knowledge made available by AGS.

Live long,

 

[oldminer]

Paul and I always disagree on the usefulness of the charts on Pricescope. They are useful to screen out undesirable qualities and to locate stones with desirable attributes. These charts were created BEFORE AGS had developed their standard for Ideal Princess cuts, but were not based on thin air. A lot of experience went into the choices on the charts. The charts are from human observation and the known characteristics of diamonds. The AGS system is way more scientific and modern and has become a "standard" since there was an otherwise vacuum of science in this field before. The AGS Ideal Princess is a unique adaptation of the princess cut style, of which Paul and other proponents of the "AGS Ideal" have a large vested interest in. They are giving you their best advice, but you must remember this particular product is the one they sell and promote. How much superior it is to diamonds which meet the highest standards as shown on the the Pricescope chart is not addressed anywhere, as far as I know. Not all AGS 0 cuts perform equally with light and this is science based.

I think the AGS Ideal princess is a beautiful diamond, but I also think it is far from the singular special stone of choice some may want you to believe. If you want a simple assurance of beauty, the AGS Ideal is a fine way to choose. I you want to shop more on a budget, or for a slightly larger diamond, then the charts on Pricescope hold great potential to lead you to a non-premium price alternative diamond.

Blast away. I am now in my flak jacket. I think highly of Paul and Rhino as honest gentlemen and great vendors in their respective markets. We don''t agree on everything and that is the best feature of Pricescope for consumers.

 

[Paul-Antwerp]

Hey Dave,

I think that I disagree with your point that we disagree. In fact, I applaud you for compiling these charts in a period, when there were probably no other such cut-tools available for fancy shapes.

And I do agree that they were useful to screen out undesirable attributes. This would mean that it is a rejection-tool (just like HCA for rounds), and that you should go into more detail after using the charts to weed out what is not worth considering.

I contend the following, though. The charts are based upon observations of actual stones, and thus are dependent upon an historic way of producing.

When AGS started grading Cut for fancy shapes, they released a lot of new information, which created the possibility of producing outside of an historically limited box. At the same time, it raised the level of cut-quality in some shapes to a level unknown before.

These stones were not part of the observations that the charts were based on. And these stones do not fall into the top-categories of the charts. The best one can say is that the charts are thus outdated.

What is worse even is the adverse effect of the charts on the top-producers. I see cutters producing AGS-0 princess-cuts trying their utmost to stay within the best parameters of the charts. And indeed, they are capable of reaching the minimum-level of AGS-0, thus obtaining both the lab cut-grade and the blessing of the charts.

However, within the field of AGS-0, there are other combinations that fall outside of the top in the charts, that do not have less spread, and that clearly outperform these. For some cutters however, the mere existence of these charts hampers them in developing these super-performers.

Just trying to put things in perspective.

Live long,

 

[oldminer]

THANKS, Paul. I didn''t think we agreed so much. This is the best news I''ve had in a while. Now I am really understanding the situation from your perspective I can appreciate it more. You may be very correct that the existence of the charts on Pricescope which I am guilty of creating back in the late 80s and early 1990''s are subverting the best efforts of cutters and the trade to stay within them and yet produce AGS 0 ideal cuts. This is the clearest explanation of the situation yet. I am sorry to be creating a problem for people while solving problems for others. It is not a good thing to trade off this way.

I never thought the charts had such impact on cutters as few people in the trade gave them more than passive acceptance. The charts rocked the boat of their complacency and they didn''t want to fuss over them making them even more noticed or more important. Yet, the trade has labored on and now improved measurements and parameters exist with AGS. Again, the general trade has passively accepted these newer parameters, but has not fully endorsed them. Its business and financial, not a beauty thing for most of the trade.

The charts could be reconfigured as a better elimination screening tool so as not to eliminate improperly so often and to include more acceptable makes. I don''t have the necessary data to do this and I don''t see anyone volunteering. If it is easy enough to do I would think some enterprising entity would do more than ignore or criticize these charts instead of revising them. In this way the charts would be even more helpful and less painful to cutters and dealers while aiding the consumer even more.

In theory, we could put together a more refined and modern set of parameters which can retain the simple system design I created some years ago. If it gets overly complex, the usefulness to consumers is reduced. It must retain the principle that overly deep diamonds look small for their weight. The relationship of visual size to carat weight is a crucial element in selecting an overall beautiful diamond. Parameters which ignore the depth relationship serve the cutter and the dealer, but hurt the naive consumer. If new charts can cover this big problem in a fair manner, then I''d be inclined to cooperate. Durability considerations and visual size considerations are both important elements of the charts as they currently exist.

 

[Rhino]

Date: 12/17/2008 4:04:51 AM
Author: Lorelei
'' Whether its $500 or $50,000 its your hard earned money and when it comes to diamonds I''m not a gambling man.''

Excellent food for thought Jon and a good reminder that one should not assume anything.

Avenger as Jules says, get the pictures if you can.

Thanks Lorelei.

I''d ditto Julie''s and Lorelei''s advice avenger because even with the angles its still a prediction and as you can tell I''m not fond of Internet crystal balls.

If the meet point symmetry or optical symmetry is off it can throw off the whole prediction of light performance. An ASET image is really more helpful or that *and* a Sarin Scan would be better.

 

[avengerzx9]

Thanks everyone for their great comments.

I do not know if they have or will give me a picture of the diamond.

However, if they can generate paperwork from AGS that said it is an ideal cut (AGS0)? Can I trust that?

 

[Lorelei]

Date: 12/17/2008 11:42:05 AM
Author: avengerzx9
Thanks everyone for their great comments.

I do not know if they have or will give me a picture of the diamond.

However, if they can generate paperwork from AGS that said it is an ideal cut (AGS0)? Can I trust that?

Just to clarify, is the diamond in question AGS graded?

 

[Judah Gutwein]

Avenger,

Figured I'd share my perspective with you in addition to what the professionals have said here.

Based upon our own experience, the charts do provide a very solid service to the customer, in that they allow the user to sift through many diamonds in order to pass over the clear underachievers. Within this framework, it can be said that the charts are akin to the HCA, in that they allow consumers to "weed" out the untold numbers of diamonds that are unworthy of any consideration. As such, the charts are an accurate metric to achieve its proper objective. In addition, princess diamonds that "do well" on these charts are often (and perhaps even consistently) very beautiful diamonds based upon our experience. There is indeed a correlation here.

However (and as others have said), there really is no way to extrapolate a (fancy) diamonds "ideal cut" status based upon incomplete and somewhat outdated information and to base a purchasing decision of this magnitude on this limited data. You would not buy a home without a comprehensive home inspection report. Buying an expensive diamond should be no different. The "numbers game" that works for rounds, doesn't carry over when it comes to fancies.

In addition, it is unethical (imo) for any vendor to ascribe an "ideal cut" designation, to a princess cut diamond that hasn't achieved this status via having been graded as such by the AGS.

There is NO other (respected) lab that has determined and created an Ideal cut grade for princess cut diamonds other than the AGS. Therefore, any vendor who offers an "ideal cut" princess diamonds not graded by this lab, is arbitrarily applying their own definition and perhaps(?) in an attempt to promote a diamond and to justify a premium.

Assuredly, these may be beautiful diamonds by any estimation. However, the specific nomenclature of "ideal cut princess", is by definition, reserved for a diamond graded as such by the AGS lab.

Best of luck!

 

[avengerzx9]

Since I am new to this, I''ve only ask whether the diamond is GIA cert or not. Therefore, I do not know if it is AGS graded?

Does that mean if a princess cut diamond is not AGS graded, you cannot tell if it is an ideal cut? Also, the vendor just mentioned to me that the diamond he is showing to me is comparable to Blue Nile Signature Princess Cut Diamond.

 

[Judah Gutwein]

Avenger,

GIA AND AGS are the standard bearers of our industry when it comes to diamond grading. However, (at the moment) only the AGS issues an "Ideal Cut" grade for princess cut diamonds. Therefore, if this diamond hasn''t been graded by AGS, it cannot be said that this diamond is "Ideal". It may very well be a beautiful stone (Blue Nile Signature princess diamonds are indeed beautiful.....), but it is not an "Ideal", period.

Within this context, it would be more accurate to say that the vendor is (arbitrarily) using the term "Ideal" to describe what may indeed be a beautiful diamond he/she is selling.

 

[Paul-Antwerp]

The main difference between the fancy charts and HCA is the following:

For rounds, HCA gives the best possible outcome based upon a limited number of averages. The result: a stone cannot perform better than the predicted HCA-score.

For the fancy charts, this is not true. A stone can perform a lot better than the prediction of the chart.

Live long,

 

[Judah Gutwein]

Paul,

Duly noted.

However, my analogy and comparison refers to the shared ability of these two metrics to actually (and accurately) weed out/reject the underachievers.

Best,

 

[Rhino]

Hi Dave,

While I feel numerical charts are incomplete/inconclusive and agree with Paul on that matter I fully agree with your comments below as I think Paul would as well.

Date: 12/17/2008 7:16:39 AM
Author: oldminer
Paul and I always disagree on the usefulness of the charts on Pricescope. They are useful to screen out undesirable qualities and to locate stones with desirable attributes. These charts were created BEFORE AGS had developed their standard for Ideal Princess cuts, but were not based on thin air. A lot of experience went into the choices on the charts. The charts are from human observation and the known characteristics of diamonds. The AGS system is way more scientific and modern and has become a ''standard'' since there was an otherwise vacuum of science in this field before. The AGS Ideal Princess is a unique adaptation of the princess cut style, of which Paul and other proponents of the ''AGS Ideal'' have a large vested interest in. They are giving you their best advice, but you must remember this particular product is the one they sell and promote. How much superior it is to diamonds which meet the highest standards as shown on the the Pricescope chart is not addressed anywhere, as far as I know. Not all AGS 0 cuts perform equally with light and this is science based.

While I do carry AGS Ideal Princess cuts I will be the first to say (and I think I have in the past) that just because it is AGS ideal doesn''t mean its the best princess cut too. Recently I have recorded visual differences in two princess cuts with close ASET images and one was markedly superior in its optics/visuals than the other. There are AGS Ideals I see, and even those with seemingly fine ASET''s that have overdarkness. A general limitation with reflectors (including ASET) is they do not always accurately convey head/body shadow which can be seen in a practical observation.

As an employer of optical technologies I appreciate where you are coming from on this perspective and I also understand your sympathy with those who are looking to get larger diamonds that do not have ideal light performance as folks like Paul and myself serve more of a niche market but it goes back to the 80/20 rule ... or in this case the 99/1 rule. I''d rather sell fewer with a clear conscience than make more money off of diamonds we have not personally inspected and given a thumbs up to. It may not be good business sense but its my conscience at the end of the day.

Have a Merry Christmas and/or Happy Chanukah if we don''t speak sooner my good friend.

All the best,

 

[avengerzx9]

All,

It looks like I will be using the charts to "weed" out the bad princess cut diamond. Since I doubt if the vendor I''ve been talking to has their diamond cert by AGS, however, it doesn''t look like AGS grading is the final verdict for the diamond as well.

I''ll be going back to the vendors today, should I be paying more attention to the percentage and angles, or should I focus more on diamond that has been AGS cert? Since the vendor is not flexible with their pricing at this time.

 

[Lorelei]

Date: 12/17/2008 11:50:10 AM
Author: avengerzx9
Since I am new to this, I''ve only ask whether the diamond is GIA cert or not. Therefore, I do not know if it is AGS graded?

Does that mean if a princess cut diamond is not AGS graded, you cannot tell if it is an ideal cut? Also, the vendor just mentioned to me that the diamond he is showing to me is comparable to Blue Nile Signature Princess Cut Diamond.

As Judah stated so eloquently, avenger - only a diamond which has an AGS report and is an AGS0 cut grade can be said to be " Ideal." So whether you can get paperwork stating that the diamond is an AGS0 depends if it has an AGS report and is an AGS0 cut grade to begin with.

 

[Lorelei]

Date: 12/17/2008 12:05:34 PM
Author: Rhino
Hi Dave,

While I feel numerical charts are incomplete/inconclusive and agree with Paul on that matter I fully agree with your comments below as I think Paul would as well.

Date: 12/17/2008 7:16:39 AM
Author: oldminer
Paul and I always disagree on the usefulness of the charts on Pricescope. They are useful to screen out undesirable qualities and to locate stones with desirable attributes. These charts were created BEFORE AGS had developed their standard for Ideal Princess cuts, but were not based on thin air. A lot of experience went into the choices on the charts. The charts are from human observation and the known characteristics of diamonds. The AGS system is way more scientific and modern and has become a 'standard' since there was an otherwise vacuum of science in this field before. The AGS Ideal Princess is a unique adaptation of the princess cut style, of which Paul and other proponents of the 'AGS Ideal' have a large vested interest in. They are giving you their best advice, but you must remember this particular product is the one they sell and promote. How much superior it is to diamonds which meet the highest standards as shown on the the Pricescope chart is not addressed anywhere, as far as I know. Not all AGS 0 cuts perform equally with light and this is science based.

While I do carry AGS Ideal Princess cuts I will be the first to say (and I think I have in the past) that just because it is AGS ideal doesn't mean its the best princess cut too. Recently I have recorded visual differences in two princess cuts with close ASET images and one was markedly superior in its optics/visuals than the other. There are AGS Ideals I see, and even those with seemingly fine ASET's that have overdarkness. A general limitation with reflectors (including ASET) is they do not always accurately convey head/body shadow which can be seen in a practical observation.

As an employer of optical technologies I appreciate where you are coming from on this perspective and I also understand your sympathy with those who are looking to get larger diamonds that do not have ideal light performance as folks like Paul and myself serve more of a niche market but it goes back to the 80/20 rule ... or in this case the 99/1 rule. I'd rather sell fewer with a clear conscience than make more money off of diamonds we have not personally inspected and given a thumbs up to. It may not be good business sense but its my conscience at the end of the day.

Have a Merry Christmas and/or Happy Chanukah if we don't speak sooner my good friend.

All the best,

Thanks Jon, again it proves we should not assume anything even with AGS0, and for the consumer to evaluate each diamond on its own physical and desirable optical properties.

 

[Rhino]

Hi Judah. Long time no see. I see where you''re going with the charts in your first paragraph ... perhaps if we were still in the 80''s it''d be relevant but the rest of your comments balance it out good.

Hi Avenger,

In answer to your questions ...

Date: 12/17/2008 11:50:10 AM
Author: avengerzx9
Since I am new to this, I''ve only ask whether the diamond is GIA cert or not. Therefore, I do not know if it is AGS graded?

It''ll generally be one or the other and not both.

Does that mean if a princess cut diamond is not AGS graded, you cannot tell if it is an ideal cut?

Correct. Only AGS can/would determine if a diamond is "Ideal Cut" by their standards. If it is "Ideal Cut" it must be AGS graded. The best that can be done with a GIA Princess cut (and there are some fine ones out there) is if a gemologist possesses the necessary hardware to generate accurate 3d models of the diamond in question to load into AGS'' proprietary ray tracing software (AGS PGS) to determine if the diiamond would qualify for "ideal light performance". It is important to note that determining "Ideal Light Performance" and the "Ideal Cut" designation are 2 seperate issues. Polish and Symmetry must be graded by AGS in addition to their ray trace exams to determine Ideal Cut.

Can a GIA graded princess cut have ideal light performance? Absolutely but it is important not to confuse the two.

Also, the vendor just mentioned to me that the diamond he is showing to me is comparable to Blue Nile Signature Princess Cut Diamond.

Which means nothing. If my understanding is correct all BN looks at is table, depth and crown height. No visual or optical inspections. Crystal ball methodology.

Hope that helps.

Peace,

 

[John P]

I hope this comparison isn’t too far out.

Imagine a traveler flying through space, preparing to enter Earth’s gravity and land. He has stated his strong desire to land in a democracy.

Without knowing specifics the “safest” advice we can give might be to aim for the USA. We know there are other democracies on the planet, but attempting to guide him to a safe landing is difficult from afar and not all borders and boundaries are as easily described as North America. Therefore the mot useful advice is to point him to the largest known target representing what he wants.

We even realize that inside the USA some regions "perform" better than others. While true, this is probably secondary to getting our traveler safely aground as he wishes... If more information is available maybe we can help guide him towards a region of preference. But the priority is still to get him inside the largest target of opportunity.

In this scenario AGS Ideal is the USA; the largest target of known performance-opportunity. While there are princess cuts not-graded by AGS that may be just as worthy it is harder to isolate them decisively.

...By the way, the situation is different if an expert can be in the cockpit with the traveler. In this case what he wants can be precisly determined and the pro can facilitate the landing with him directly.

 

[oldminer]

AGS is a position of some authority, but it is hardly the only valid authority. An entity wishing to use the AGA Cut Class system to call Class 1a and 1b diamonds "Ideal" or using GCAL grading reports, or Gemex report with light behavior/cut grading results in them could make their own call of what is "Ideal". So long as their system is open, can be understood and fully criticized openly, I see no foul being committed.

"Ideal" is only a word category and not anyone''s "brand name". An ideal cut diamond is one with all the best attributes under the system it is being graded under. There are differences in the validity and scope of the various systems in use. I have yet to meet anyone who was dissapointed with the beauty or durability of an AGS0, a Blue Nile Signature series, or an AGA 1A or 1B Cut Class diamond..... There were different systems at work and maybe some stones whcih deserved consideration were rejected wrongly, but the end result was a consumer with a wonderfully beautiful and durable diamond. There are political and business forces at play which work to prevent bringing total agreement to diamond cut grading. At the very top of cut grading there are few major problems in getting to excellent stones. As we move away from the very pinnacle of top cut, the systems diverge more and we likely could do better if all the players wished to make it happen. It just seems unrealistic to think that everyone wants standardization. They might AGREE to discuss it, but REALLY don''t want to give up on their brand image, either. Brand image has cost the major players such as AGS, BN and GCAL tons of money to successfully market. You can''t expect them to give up their unique brand image without a major struggle.

 

[avengerzx9]

All,

Thanks again for helping me out with this.

I will report back later tonight on the status of the different diamonds.

At the very least I will weed out the diamond that falls out of the range from the chart and try to stick to this principle "don''t bother with prince cut with tables that are larger or greater than their total depths"

T

 

[Judah Gutwein]

Hi Rhino;

Ditto, Long time. Is that pizza place still next to your store?

From what I read here, I believe we are all in agreement that consumers can Not make an accurate evaluation and purchase decision to purchase a fancy shape diamond, e.g.; Princess, Cushion, Asscher, Oval, Radiant, Marquise, Pear, et al; based on charts alone. "Numbers" tell you nothing about the diamonds light performance, shape outline and shape definition. The fact is that you can have two Princess Cut diamonds with the same exact specs that will "l@@k" different and display significantly different optical light performance.

Consumers do indeed deserve the best diamond they can buy for their hard earned money and to this end we are not operating in the "80's" but employ the current technologies to assess light performance, including Idealscope, ASET scope, and Brilliancescope analyses in evaluating the diamonds we sell.

We all agree on the importance and benefit for the consumer to be provided with the totality of all of this information.

Avenger, Good Luck to you and let us know how you make out.

 

[oldminer]

"The fact is that you can have two Princess Cut diamonds with the same exact specs that will "l@@k" different and display significantly different optical light performance"


Judah:

I could take issue with other statements you just made, but the one above is the worst of the group. I know you feel passionate on the subject, but overstatement is not better than fair statement of the facts.

I would say that if you had two princess cut diamonds of equal transparency, UV reaction, color and clarity which were absolutely also identical in cut, they would act identically with light. However, the chance for such a rare event to occur is remote. Two diamonds would rarely be the identical in transparency, UV reaction, color, clarity to begin with. Diamonds of the same GIA color grade are often visibly different in color appearance to experts. Then, even more rare, would be two diamonds with every facet angle, length, polish and symmetry be found IDENTICAL. The REASON diamonds which are approximately the same play differently with light is that these apparently matching diamonds are NOT IDENTICAL and NEVER HAVE EXACT SPECS which match.

Screening tools are useful and words to the contrary do not come with any more authority than those of opposing opinions. It is okay to observe diamonds with any of the highly useful tools such as IS, ASET and Brilliancescope, etc, but clients still need to interpret results and pick a diamond they like the looks of. We want them not to make foolish, impulsive choices. We want them to avoid small looking diamonds because the girdles are too thick or the depth is overly deep. We want them to avoid extremely thin girdles and shallow crown angles for the sake of durability concerns. All of this can be accomplished well with parametric tools.

If you look at the cut specs of any large sample of Ideal Cut diamonds such as AGS 0 stones, you will find there are sets of parameters which ALWAYS lead to AGS calling the stone IDEAL. This proves that some sets of numerical parameters can give you the Ideal result. You just have to crunch the data to make those calls. Diamond rough, being a natural product with inherent characteristics and difficulty in cutting, does not always make the task an easy one. That is what leads to wide variation. If diamonds were made of CZ, there would be no problem with parameters as a basis since wasting material in cutting would not be a consideration.

 

[Judah Gutwein]

David,

Instead of dealing in semantics, I'll just respectfully agree to disagree

With all due respect, I think it is self understood that consumers are (typically and at the very least, initially) informed by the information gleaned from the grading report alone.

To this end, there will indeed be diamonds with "identical specs" and information on their respective reports that will subsequently not look the same to the observer.

This is why the added information is important and encouraged by everyone on this thread. My quoted statement, was not intended to be any more (scientifically) complex (ie: "UV reaction, trancparency, facet angle, length, etc"), than its most basic, accurate and practical ramifications (of said statement) to the consumer. Within this context, there is no "overstatement".

The advice given to this consumer by all, is both helpful and informative.

Best,

 

[oldminer]

Consumers should know that identical specs on reports do not equate to identical diamonds or identical performance promises. This is because the amount of data on reports,, though increasingly more complex and detailed, is far from complete information. Diamonds that might appear to be identical therefore may not be identical in appearance or performance because of the unreported measurements not provided on those reports.

I actually think we agree on most of this and our disagreement is how to handle providing the information we do give to consumers. How do we word the presentation to be honest, yet still remain a positive sales pitch, to make that all important sale. Most retailers struggle with this, but we see some Pricescope vendors who have developed excellent approaches to explain cut grading and light behavior. Visiting their websites is an education that the entire trade ought to take the time to learn about.

The process of discussion and hairsplitting we go through here is no indication of animosity for one another. Holding different views and being able to communicate them well is a life long process that takes great practice and patience with one another. I appreciate the responses and other views presented. It helps to mould my own thoughts over time to fit the realiity we live in.