Show me examples of good numbers, poor idealscope

[teobdl]

The "perfect example" linked above is not a good one.

Pfunk wrote, "I am curious if someone could provide me images of diamonds that seem to have great numbers on paper, but have poor idealscope images that would translate to visual defects in real life?"

The visual effects of that slight windowing on that diamond would be incredibly marginal, and I would think it would undetectable to the unaided eye vs a diamond w/ those same proportions but without the windowing... at least the differences would not lead one to say unequivocally that the diamond has deficient "light performance" in real life.

In fact, if I remember correctly, sometime last year Sergey suggested that, in some circumstances, slight leakage can create a "bright flash" effect due to stereo vision and competing inputs ([one eye = flash] + [one eye = blank] ==> [extra bright flash]). There were some very cool examples posted in that thread.

Again, how noticeable this visual effect would be in real life vs a non-leakage diamond is unknown to me, but it certainly leads me to believe that small windowing such as the one shown in the linked diamond does not universally lead to "visual defects in real life."

 

[Texas Leaguer]

I want to pick up on a point Wink made regarding the very special nature of the diamond purchase. I do believe this is a factor in the tendency of many here to be uncompromising on cut quality.

Many of the posters seeking opinions and guidance are couples buying diamond engagement rings. The diamond is a symbol of something priceless and emotional, and will be worn every day for a lifetime. In this context squeezing that extra portion of performance out of the diamond is seen by many as being well worth the premium.

Despite the fact that it may not be immediately apparent, over the course of time and zillions of different viewing environments precision cutting will make a difference in real life.

This may be one of the most difficult things to demonstrate or even articulate. It’s almost like the challenge of proving a negative. It’s not so much about what you get with precision – it’s more about what’s missing with imprecision. And at some level the differences are very subtle, yet real.

 

[teobdl]

I appreciate that many, likely a majority on PS, want the most precisely cut diamond possible. That is completely, perfectly acceptable to me. I also don't mind if people want D color, or flawless clarity.

But I do think that these levels of "perfection" are similar in their characteristic of being, in real life situations, extremely similar if not indistinguishable to the unaided human eye when compared to their respective slightly lower grades.

I have trouble with the following:

In this context squeezing that extra portion of performance out of the diamond is seen by many as being well worth the premium.

Despite the fact that it may not be immediately apparent, over the course of time and zillions of different viewing environments precision cutting will make a difference in real life.

This may be one of the most difficult things to demonstrate or even articulate. It’s almost like the challenge of proving a negative. It’s not so much about what you get with precision – it’s more about what’s missing with imprecision. And at some level the differences are very subtle, yet real.

The other problem for me is that all of the appeal for precision cut diamonds is being couched in scientific terms, and yet when we ask how and in what ways this extra drop of precision will make a difference in real life,the answer is that it's too hard to articulate.

It sounds almost like this sales pitch: "Buy this glass of water because it has 3 extra drops that, over time, will make you more hydrated"--technically yes, but in such a subtle way that you literally will not notice.

Will the diamond be brighter, or more dynamically interesting? The answer is technically yes, but in such a subtle way that you almost definitely wouldn't notice.

 

[pfunk]

I've shot all this in video. GIA X diamond with 34.5/40.8 and AGS 2 in light performance with sub par optics. Not sure if I have the graphics saved as I shot this a while back but in answer to your question YES ... I would never lay out my capital on just the average numbers alone even if they appear to be the best on paper.

Rhino, thank you for the responses. I have watched MANY of your videos online and they are immensely helpful, which is impressive considering how hard it must be to capture subtle differences on video. Even as advanced as cameras are today, you just can't match the human eye. This response prompts a few questions from me if you don't mind.

1. Is it typical to see a diamond cut to these angles (assuming a table from 53-58 and excellent symmetry/polish) falling to AGS 2 in performance, or would it be more common to fall into AGS 0 or 1?

2. In this case, do you know what was the cause for the drop in performance to AGS 2? Was it a result of GIA rounding, or was there some other defect in cut? Was it due to another factor such as an impact from clarity?

3. Was idealscope or diamXray able to detect the defects?

 

[KobiD]

This is a very interesting thread with great input from many of the big players, and although it has gone off topic a bit its still generating good information. Pfunks questions above are good too.

I see two camps when it comes to the cutters.

First come those interested in quantity (carat weight) over quality; ala deep steep stone cut from the rough to retain weight and sell at a higher price. The market is full of these, and from a financial point of view it has always been what makes sense to a cutter.

Then we have the precision cutters, willing to sacrifice some weight in the name of a stronger performing diamond. By pushing for stones cut to perfection it truly results in better products for everyone, and as consumbers move in this direction it will eventually change the priorities of the first group. Again, a win-win situation (particularly for the consumer).

So for the experts, are the stones that grade at ideal, but may fall short of super-ideal cut this way intentionally? It is a balance of time vs reward for the cutter, or a result of miscalculation while striving for perfection? Of course all cutters aren't made equally as well.

I think the issue with buying from numbers alone is that due to the rounding you can't form an appreciation for the individual diamonds symmetry at all. If a vendor is going to spend the time to photograph a diamond, then it probably only takes a little more time to also provide any other supporting data they can, and as a consumer why wouldn't you want as much information as you can get? But at the same time, if you do stick within the tight middle range of TIC (and avoid the egdes) I think finding a truly poor performing diamond would be the exception.

 

[teobdl]

if you do stick within the tight middle range of TIC (and avoid the egdes) I think finding a truly poor performing diamond would be the exception.

This is correct.

 

[Texas Leaguer]

I appreciate that many, likely a majority on PS, want the most precisely cut diamond possible. That is completely, perfectly acceptable to me. I also don't mind if people want D color, or flawless clarity.

But I do think that these levels of "perfection" are similar in their characteristic of being, in real life situations, extremely similar if not indistinguishable to the unaided human eye when compared to their respective slightly lower grades.

I have trouble with the following:

In this context squeezing that extra portion of performance out of the diamond is seen by many as being well worth the premium.

Despite the fact that it may not be immediately apparent, over the course of time and zillions of different viewing environments precision cutting will make a difference in real life.

This may be one of the most difficult things to demonstrate or even articulate. It’s almost like the challenge of proving a negative. It’s not so much about what you get with precision – it’s more about what’s missing with imprecision. And at some level the differences are very subtle, yet real.

The other problem for me is that all of the appeal for precision cut diamonds is being couched in scientific terms, and yet when we ask how and in what ways this extra drop of precision will make a difference in real life,the answer is that it's too hard to articulate.

It sounds almost like this sales pitch: "Buy this glass of water because it has 3 extra drops that, over time, will make you more hydrated"--technically yes, but in such a subtle way that you literally will not notice.

Will the diamond be brighter, or more dynamically interesting? The answer is technically yes, but in such a subtle way that you almost definitely wouldn't notice.

Teobdl,
Let me try to describe the extra drop this way. We know that performance derives from the interplay of light with the diamond's facets. We also know that a given facet can be reflecting/refracting multiple light rays from multiple locations. These "virtual facets" are really what defines the light performance of the diamond. The more precisely the facets are aligned in 3 dimensional space, the more optimized the virtual facets become in terms what they deliver. The facet design prescribes a specific collection of virtual facets of different sizes and capabilities. Only by precise execution on the part of the cutter is the full potential of the design realized.

Here's an off the wall analogy: I am a salad lover. I like alot of stuff in my salads including different colors and textures. It usually includes some nice chunky pieces of romaine, smaller pieces of green and red bell pepper, even smaller shreds of herbs, etc. I take care to prepare it in a particular way. If I gave the exact same ingredients to someone else and they chopped it all up too small, it would not be as enjoyable to eat. The basic design constituents of the salad are the same, but the execution is not as good.

Small deviations in proportions and facet aligment can have significant impacts on the size and distribution of virtual facets. As a result there are going to be things that the diamond is expected to deliver which it will not in certain conditions. When and how you fail to experience this missing performance is difficult to predict. But you will miss it.

 

[Rhino]

Hey pfunk,

Firstly ... do you play that funky music white boy?

I've shot all this in video. GIA X diamond with 34.5/40.8 and AGS 2 in light performance with sub par optics. Not sure if I have the graphics saved as I shot this a while back but in answer to your question YES ... I would never lay out my capital on just the average numbers alone even if they appear to be the best on paper.

Rhino, thank you for the responses. I have watched MANY of your videos online and they are immensely helpful, which is impressive considering how hard it must be to capture subtle differences on video. Even as advanced as cameras are today, you just can't match the human eye.

True but we find it the next best thing to seeing it live.

This response prompts a few questions from me if you don't mind.

1. Is it typical to see a diamond cut to these angles (assuming a table from 53-58 and excellent symmetry/polish) falling to AGS 2 in performance, or would it be more common to fall into AGS 0 or 1?

The latter. The fact they exist is key though and precise optical symmetry must never be assumed. That being said the question we want answered is how far those azimuth angles are off which can never be answered from paperwork alone.

2. In this case, do you know what was the cause for the drop in performance to AGS 2? Was it a result of GIA rounding, or was there some other defect in cut? Was it due to another factor such as an impact from clarity?

in the example I use in the video it was due to a combination of upper half facets that were cut too steep, resulting in drawing in too many reflections off the horizon (0-45 degree angular spectrum) as well as azimuth angles on the pavilion halves that twisted too far causing unwanted leakage under the table.

3. Was idealscope or diamXray able to detect the defects?

Only the leakage under the table. I do not like or endorse red reflectors for analyzing all the factors though. The ASET was able to show us the results of the steeper upper half angles.

Thanks for your questions.

All the best,
Rhino

 

[John P]

So for the experts, are the stones that grade at ideal, but may fall short of super-ideal cut this way intentionally? It is a balance of time vs reward for the cutter, or a result of miscalculation while striving for perfection? Of course all cutters aren't made equally as well.

It's a matter of commercial intent. Skill, sure, but just as much it's added extra time in planning/execution, more expensive tools and a high rate of rejection. True fine make productions are rare.

Pfunk asked a relevant question earlier.

Let me ask you this then: is a good pattern of hearts and arrows indicative that the deviation from the average is small? Or does the pattern of hearts and arrows tell you nothing about the deviation from average?

Physical perfection is almost never practical. There's the natural hardness, but also crystal structure, graining and characteristics which demand deviation. This is where factory floors differ in goals and associated costs. Assembly line polishers don’t worry about those nuances. Indexing is changed a bit (paint or dig) they just polish wide deviations that they know will “get the grade” with averaging, etc. The goal is a carat weight and averages. And there's no information whatsoever about the 16 upper girdle facets on a grading report, which is why you find many diamonds where slight indexing changes show up in reflectors.

With fine-make more time goes into planning and especially execution. This is because side to side adjustments are made by the polisher to preserve the diamond's 3D optical-precision. It requires superior tools and increased time, as well as a philosophical dedication to the end result. It's not just about the result in a 2D photo, which can be skewed anyway. One sees infinitely more when using these scopes live, which is no different than using a loupe compared to a magnified photo. And, of course, no image is a substitute for looking at the diamond itself truly, in many lighting situations, over a period of time.

Say all that to say; it's not "miscalculation" on one side. It's commitment on the other.

 

[Texas Leaguer]

I've always liked this Venn diagram. Top cut quality lives at the intersection of a philosophical dedication to maximum beauty, expert planning and design, and superb craftmanship.

 

[cflutist]

I've always liked this Venn diagram. Top cut quality lives at the intersection of a philosophical dedication to maximum beauty, expert planning and design, and superb craftmanship.

Imo, CBI, WF-ACA, GOG Superior H&A, and BGD Sig lie at the intersection of all three circles.
I am one of the minority who didn't mind paying for 3D cutting perfection when I ordered my Cut to Order CBI diamond.

 

[luvdajules]

Thanks, Rhino (and other trade people who help us learn), especially the last post regarding red reflector imaging. I took note because some vendors say that IS is all you need, that on rounds ASET is not necessary if you have the IS. I knew this didn't sound right to me for all cases of diamond makes, but didn't argue. It's nice to get clarity.

 

[John P]

I'm late to the thread. The discussion has morphed into nuance-interp. I love that topic and will come back to it.

Meanwhile, the Subject of this thread is: "Show me examples of good numbers, poor idealscope.", which seems a different question. Touched-on here:

if you do stick within the tight middle range of TIC (and avoid the egdes) I think finding a truly poor performing diamond would be the exception.

This is correct.

With that philosophy I would suggest that IS-ASET are an added layer of protection. They prevent the buyer from the exception. They raise confidence and avoid returns. That is better for the vendor and better for the client, especially for someone in a time-crunch who hasn't time to send things back and forth.

 

[KobiD]

I'm late to the thread. The discussion has morphed into nuance-interp. I love that topic and will come back to it.

Meanwhile, the Subject of this thread is: "Show me examples of good numbers, poor idealscope.", which seems a different question. Touched-on here:

if you do stick within the tight middle range of TIC (and avoid the egdes) I think finding a truly poor performing diamond would be the exception.

This is correct.

With that philosophy I would suggest that IS-ASET are an added layer of protection. They prevent the buyer from the exception. They raise confidence and avoid returns. That is better for the vendor and better for the client, especially for someone in a time-crunch who hasn't time to send things back and forth.

Thanks John. I don't think anyone will disagree with you there, but the question still remains. For those who work with volumes of diamonds how often does an exception to the rule present? and if something is classified as an exception, at what level is it considered/deemed to be a poor performer/choice? Does anyone have reflector images that demonstate this?

Also appreciate the additional information regarding the cutting process. In my example regarding two trains of thought, it obviously left out the cutters who target the edges of the ideal/ex ex ex range purposely trying to make the grade but with as much retained weight as possible.

 

[Texas Leaguer]

I'm late to the thread. The discussion has morphed into nuance-interp. I love that topic and will come back to it.

Meanwhile, the Subject of this thread is: "Show me examples of good numbers, poor idealscope.", which seems a different question. Touched-on here:

if you do stick within the tight middle range of TIC (and avoid the egdes) I think finding a truly poor performing diamond would be the exception.

This is correct.

With that philosophy I would suggest that IS-ASET are an added layer of protection. They prevent the buyer from the exception. They raise confidence and avoid returns. That is better for the vendor and better for the client, especially for someone in a time-crunch who hasn't time to send things back and forth.

Thanks John. I don't think anyone will disagree with you there, but the question still remains. For those who work with volumes of diamonds how often does an exception to the rule present? and if something is classified as an exception, at what level is it considered/deemed to be a poor performer/choice? Does anyone have reflector images that demonstate this?

Also appreciate the additional information regarding the cutting process. In my example regarding two trains of thought, it obviously left out the cutters who target the edges of the ideal/ex ex ex range purposely trying to make the grade but with as much retained weight as possible.

Kobi,
I'm sure John will have thoughts on this, but it does go back to what Paul mentioned. It depends on your definition of poor. I will say this, it is very common for GIA triple ex, even those with good numbers, to have poor optical precision. Is the diamond still attractive? Yes. Is it's full potential diminished significantly. Yes. (I tried to make that case above) Does that make it a poor cut? Maybe not for some folks, but for others it's a deal breaker.

There is good reason to require the extra information if your intent is to select a diamond that will deliver top light performance throughout a full spectrum of real world lighting conditions.

 

[KobiD]

Kobi,
I'm sure John will have thoughts on this, but it does go back to what Paul mentioned. It depends on your definition of poor. I will say this, it is very common for GIA triple ex, even those with good numbers, to have poor optical precision. Is the diamond still attractive? Yes. Is it's full potential diminished significantly. Yes. (I tried to make that case above) Does that make it a poor cut? Maybe not for some folks, but for others it's a deal breaker.

There is good reason to require the extra information if your intent is to select a diamond that will deliver top light performance throughout a full spectrum of real world lighting conditions.

So lets define poor performance for the sake of this thread. I know everyones opinion will vary, but in terms of an ideal scope image for example, is a lighter shade under the table indicative or poor performance, or simply lesser performance? Partial leakage vs complete.

Also, with all the focus on face down imaging, I'm curious as to how reflectors change as some tilt is introduced.

 

[diamondseeker2006]

I've always liked this Venn diagram. Top cut quality lives at the intersection of a philosophical dedication to maximum beauty, expert planning and design, and superb craftmanship.

Imo, CBI, WF-ACA, GOG Superior H&A, and BGD Sig lie at the intersection of all three circles.
I am one of the minority who didn't mind paying for 3D cutting perfection when I ordered my Cut to Order CBI diamond.

I am in the minority with you, cflutist!!! I buy diamonds with future heirlooms in mind, and I want the best!

(However, I do recommend stones almost daily that I would not buy for myself because some people desire to maximize other C's over cut and almost everyone is working within a budget. I still strongly favor stones that have some kind of image..idealscope or ASET and am happy to see drop shipper (almost) vendors starting to provide this on some of their stones, as Bryan mentioned earlier.)

 

[pfunk]

First of all, as luvdajules mentioned, big thanks to the experts for sharing their thoughts here. I've read many threads on here and the ones in which you all get involved turn into wonderful educational pieces. Considering how busy you all are, I thank you for giving me and other newbies your time.

John, when you mention skewing of a 2d hearts image, do you mean to say they can be manipulated to show better optical symmetry than you might see when viewing the stone live through the scope? Or do you just mean that you can't glean as much from a 2d image as you can when actually viewing the stone in person?

If we are to talk about making tradeoffs and compromises in the buying process, let me pose a question I wondered about but did not know the answer to. We know that precision cuts mean all facets are aligned perfectly resulting in virtual facets that maximize the stone's potential and beauty. When I debated super ideal vs ideal, I considered the tradeoffs I could make in the 4 c's to get what I knew SHE wanted. Size was of bigger concern to her, while I personally was not willing to compromise TOO much on cut. In the same budget I could go up in size enough to make a noticeable visual difference.

This brings me to my question. Despite having a cut less than super ideal, the facets of the diamond are larger. Even with less than perfect cut, does the fact that the facets are larger produce a greater visual impact, much like precision cutting would?

Mind you, the diamond I bought does exhibit a good pattern of hearts and is, from what I can tell, a very good performer and beautiful to me. Where it certainly compromises in potential is a slightly thick girdle to make an important jump in carat weight. I was ok with this though, as I know it will make her happy to be able to say her diamond is 2 carats and the info was available that proved to me it was cut with optical symmetry. This is, to me and my situation, why I did not jump to super ideal. It would have meant a noticeably smaller stone, albeit presumably more beautiful if one knows what to look for.

 

[MelisendeDiamonds]

Pfunk,

(Here are some comments as I quickly read this thread)

It just doesn't make sense to cut a diamond with a high degree of 3D optical symmetry(resulting in ideal Hearts and Arrows) and not also get Tolk proportions as well. That is an academic red herring, the economics of planning any piece of rough and the process make this highly unlikely.

Also showing customers the differences between "Near Tolk","Tolk", "Superideal H&A" in their size and color preference is often not economically viable as well. Availability & Price are much more important than the subtle and often imperceptible differences between them.

CA/PA combination dwarves many other considerations when considering fine makes already within the GIA XXX range. The GIA system works for the industry in general and is the most widely accepted cut grading we have. Sure their are outliers, false positives, and some of the GIA range(especially the borders) are visually less appealing than the zenith but most GIA XXX are well cut diamonds to all but the most fanatical who have likely already bought into the hype and marketing of the "Superideals". As you go from one level to the next within the middle of the GIA XXX range the detectable differences with the human eye become less obvious until they are not noticeable without magnification.

The answers you have gotten from trademembers and pricescope faithful who sell, support, and market "Superior Cut" and "Superideals" and the consumers who self validate their own purchases from these very vendors should be taken into proper perspective. It is very much still a niche taste and a "Mind Clean" aspect. It is also a high concentration of the sponsoring and participating trade here who focus on this section of the market.

I believe the law diminishing returns applies and for most of our customers that premium is not justified. Now to be fair the premium difference is often greater in my local market than it would be in the United States. If the gap were smaller it might make sense to a wider segment of the market.

For 99% of our customers GIA XXX is good enough, we tend to shoot for the middle of the GIA range, and usually I'm not going to import from Antwerp "Superideals" unless the customer really wants it and is willing to pay the premium for the AGS 0000 "Superideal" with the images. But when the customer balks at the price premium that usually ends that option. We would prefer to source from our local production or that what is already readily available in Canada.

My position isn't one of lack of technical expertise or understanding, I have a DC license, have a library of hundreds of scans and have done hundreds of comparisons for customers. I could probably point out things that are not often spoken about on Pricescope. For example Hearts images can be "smoothed" out and flaws hidden depending upon the DOF and contrast used. Its up to the vendor how "nice" they want their hearts to look even for diamonds with less than near perfect 3D optical precision. I find the less experience once has the more nitpicky they might be and this doesn't always translate into noticeable differences with normal human vision.

 

[Texas Leaguer]

Pfunk,

(Here are some comments as I quickly read this thread)

It just doesn't make sense to cut a diamond with a high degree of 3D optical symmetry(resulting in ideal Hearts and Arrows) and not also get Tolk proportions as well. That is an academic red herring, the economics of planning any piece of rough and the process make this highly unlikely.

Also showing customers the differences between "Near Tolk","Tolk", "Superideal H&A" in their size and color preference is often not economically viable as well. Availability & Price are much more important than the subtle and often imperceptible differences between them.

CA/PA combination dwarves many other considerations when considering fine makes already within the GIA XXX range. The GIA system works for the industry in general and is the most widely accepted cut grading we have. Sure their are outliers, false positives, and some of the GIA range(especially the borders) are visually less appealing than the zenith but most GIA XXX are well cut diamonds to all but the most fanatical who have likely already bought into the hype and marketing of the "Superideals". As you go from one level to the next within the middle of the GIA XXX range the detectable differences with the human eye become less obvious until they are not noticeable without magnification.

The answers you have gotten from trademembers and pricescope faithful who sell, support, and market "Superior Cut" and "Superideals" and the consumers who self validate their own purchases from these very vendors should be taken into proper perspective. It is very much still a niche taste and a "Mind Clean" aspect. It is also a high concentration of the sponsoring and participating trade here who focus on this section of the market.

I believe the law diminishing returns applies and for most of our customers that premium is not justified. Now to be fair the premium difference is often greater in my local market than it would be in the United States. If the gap were smaller it might make sense to a wider segment of the market.

For 99% of our customers GIA XXX is good enough, we tend to shoot for the middle of the GIA range, and usually I'm not going to import from Antwerp "Superideals" unless the customer really wants it and is willing to pay the premium for the AGS 0000 "Superideal" with the images. But when the customer balks at the price premium that usually ends that option. We would prefer to source from our local production or that what is already readily available in Canada.

My position isn't one of lack of technical expertise or understanding, I have a DC license, have a library of hundreds of scans and have done hundreds of comparisons for customers. I could probably point out things that are not often spoken about on Pricescope. For example Hearts images can be "smoothed" out and flaws hidden depending upon the DOF and contrast used. Its up to the vendor how "nice" they want their hearts to look even for diamonds with less than near perfect 3D optical precision. I find the less experience once has the more nitpicky they might be and this doesn't always translate into noticeable differences with normal human vision.

I agree with a large part of this take Haroutioun. I always look forward to hearing your views as they are a product of both experience and technical knowledge. Even when we don't agree I find your no-nonsense approach a valuable addition to the conversation, usually challenging, and frequently provocative!

I have enjoyed this discussion so far and I would like to thank pfunk and Kobi for facilitating and sustaining it with so many good questions and comments. You may not realize this but most guys come on to the forum, do their research, get their business done and move on with their lives. Not that many of them stay around to continue to learn and contribute to the pricescope community. I hope you are both active here for a long time.

What I find particularly interesting about this conversation and some of the slight diversions that have been taken, is that it has hit upon so many important aspects of diamond buying. Not only the technical aspects, but some of the personal/psychological considerations, historical aspects that have brought us to this place, and where is all this taking us from here. And of course how we separate practical realities from the inevitable marketing spin always present in the world of commerce.

I have some thoughts that I will share later. But now I must attend to some weekend chores.

 

[Karl_K]

It just doesn't make sense to cut a diamond with a high degree of 3D optical symmetry(resulting in ideal Hearts and Arrows) and not also get Tolk proportions as well. That is an academic red herring, the economics of planning any piece of rough and the process make this highly unlikely.

I disagree with that in the real world I have seen diamonds that were fics, bics, steep-deeps, shallow-shallow. and oec with high levels of 3d optical symmetry some with images that would be called h&a some not.
Not to mention princess, asschers and other fancies.
Fancies can benefit from high levels of 3d optical symmetry even more so than a RB.

It just so happens that 3d optical symmetry in a RB of certain proportions results in a marketable image under a viewer that looks kewl so we hear about it more.

 

[Texas Leaguer]

Pfunk,

(Here are some comments as I quickly read this thread)

It just doesn't make sense to cut a diamond with a high degree of 3D optical symmetry(resulting in ideal Hearts and Arrows) and not also get Tolk proportions as well. That is an academic red herring, the economics of planning any piece of rough and the process make this highly unlikely.

Also showing customers the differences between "Near Tolk","Tolk", "Superideal H&A" in their size and color preference is often not economically viable as well. Availability & Price are much more important than the subtle and often imperceptible differences between them.

CA/PA combination dwarves many other considerations when considering fine makes already within the GIA XXX range. The GIA system works for the industry in general and is the most widely accepted cut grading we have. Sure their are outliers, false positives, and some of the GIA range(especially the borders) are visually less appealing than the zenith but most GIA XXX are well cut diamonds to all but the most fanatical who have likely already bought into the hype and marketing of the "Superideals". As you go from one level to the next within the middle of the GIA XXX range the detectable differences with the human eye become less obvious until they are not noticeable without magnification.

The answers you have gotten from trademembers and pricescope faithful who sell, support, and market "Superior Cut" and "Superideals" and the consumers who self validate their own purchases from these very vendors should be taken into proper perspective. It is very much still a niche taste and a "Mind Clean" aspect. It is also a high concentration of the sponsoring and participating trade here who focus on this section of the market.

I believe the law diminishing returns applies and for most of our customers that premium is not justified. Now to be fair the premium difference is often greater in my local market than it would be in the United States. If the gap were smaller it might make sense to a wider segment of the market.

For 99% of our customers GIA XXX is good enough, we tend to shoot for the middle of the GIA range, and usually I'm not going to import from Antwerp "Superideals" unless the customer really wants it and is willing to pay the premium for the AGS 0000 "Superideal" with the images. But when the customer balks at the price premium that usually ends that option. We would prefer to source from our local production or that what is already readily available in Canada.

My position isn't one of lack of technical expertise or understanding, I have a DC license, have a library of hundreds of scans and have done hundreds of comparisons for customers. I could probably point out things that are not often spoken about on Pricescope. For example Hearts images can be "smoothed" out and flaws hidden depending upon the DOF and contrast used. Its up to the vendor how "nice" they want their hearts to look even for diamonds with less than near perfect 3D optical precision. I find the less experience once has the more nitpicky they might be and this doesn't always translate into noticeable differences with normal human vision.

I agree with a large part of this take Haroutioun. I always look forward to hearing your views as they are a product of both experience and technical knowledge. Even when we don't agree I find your no-nonsense approach a valuable addition to the conversation, usually challenging, and frequently provocative!

I have enjoyed this discussion so far and I would like to thank pfunk and Kobi for facilitating and sustaining it with so many good questions and comments. You may not realize this but most guys come on to the forum, do their research, get their business done and move on with their lives. Not that many of them stay around to continue to learn and contribute to the pricescope community. I hope you are both active here for a long time.

What I find particularly interesting about this conversation and some of the slight diversions that have been taken, is that it has hit upon so many important aspects of diamond buying. Not only the technical aspects, but some of the personal/psychological considerations, historical aspects that have brought us to this place, and where is all this taking us from here. And of course how we separate practical realities from the inevitable marketing spin always present in the world of commerce.

I have some thoughts that I will share later. But now I must attend to some weekend chores.

Here are a few comments specific to the above. One of the reasons there is a premium for fine makes that seems to price some buyers out is a historical mindset about cutting for weight coupled with marketing around that premise. That is how we arrived at a place where magic marks like the 1.00ct size became somehow magical enough to trump other considerations. But it is true that when you know that your SO really has her heart set on owning a one carat or a two carat diamond, it is a good idea to give that much weight in your decision matrix, even if it means selecting a diamond that is hiding some weight, possibly resulting in a cut grade deduction or even loss of performance.

I share Paul's opinion that the law of diminishing returns does not apply to diamonds in the same way it does with other purchases. Not only is it a very long horizon in terms of deriving benefit from that last drop of quality, but the emotional and symbolic nature of the purchase makes it worth knowing that no compromise has been made in the only aspect of diamond value that man has complete control over.

Having said that, there is still the element of availability and price that can detemine whether it is practical or even possible to hold out for the last drop. But my contention is that if the philosophy of diamond cutting was more universally oriented in the direction of cutting for beauty over weight, there would be more availability of top cuts and that compromise would not have to be made as often as it is today. I also believe that the trend is clear and the mindset is changing and in the future the decision making process will be different with respect to cut quality.

When AGS established their lab in the mid 1990's and their Ideal cut began to gain some attention and was embraced by that small niche devoted to the best in diamond craftsmanship, the bar was raised. It can be argued that this was the reason that GIA started to feel serious pressure to come out with a cut grade system of their own. But being a large and conservative organization with a very traditional constituency, you could almost feel the hand wringing, hair pulling and hand sitting that was going on for almost a decade before they finally pulled the trigger. Although many purists criticize the GIA cut grade system as overly broad, it almost immediately started to change the mindset of the market from the manufacturer down to the consumer. Where mediocre cuts dominated the market, soon customers were demanding Triple Ex and more manufactures began cutting to the new standard, significantly improving the overall beauty of the diamonds coming onto the market. So we don't have to look back very far to see how progress starts with the philosophy and it affects everything from consumer demand, to marketing, and manufacturing.

When AGS decided to devote themselves to scientific light performance grading, they raised the bar yet again. Now there is a system for evaluating the cut quality of the individual diamond and calculating light performance based upon the contribution of every facet, including some of the effects of optical precision.

But even this standard is overly broad for some purists, and it is possible with various tools to make even narrower ddistinctions of quality. Hence, the super-ideal is appealing to many modern consumers. Is that a result of marketing or a result of response to market demand? And is it crazy thinking on the part of the consumer to want that last drop, or is it inevitable because technology gives us the ability to cut diamonds to a higher level of precision today?

Should we have stopped at a place before AGS or should we have pushed that boundary for another drop? Should we now be satisfied because "for 99% of customers GIA XXX is good enough", or should we hold out for another drop? Are consumers who are advocates of the highest cut quality possible really just 'self validating' their own premium purchases? Or are these the same voices that have finally helped lead us into the light as an industry that seemed mired in mediocrity for a century?

Because diamonds are not all cut with ultimate precision for various reasons there are reasonable and rational compromises that are made every day. And while our company can be rightly considered a niche business and best known for our brand of super ideal, we have three other categories of diamonds that provide a full range of choices. Yet none of the diamonds we sell are "ugly" or "hideous"! But that in no way means that the super ideals are not fully worth their premium to a growing number of educated consumers.

To characterize this portion of the market as "the most fanatical who have likely already bought into the hype and marketing of the 'Superideals' ", is not only demeaning to them, but it fails to recognize the significant contribution they make to our progress as an industry.

 

[luvdajules]

I love this read (although my tendencies lean toward the practical aspects and less technical, but love to read). I just wanted to give my personal experience to answer a couple questions of the OP regarding size thresholds for clarity and facet size. Imho, this threshold is somewhere around 1.5 ct to 1.7 ct for both clarity and facet size, certainly by 2 ct. (7.5 mm - 8.0 mm diameter), depending on hawk eyes and definition of eye clean to what distance and side view.

I've read that many diamond sellers are very cautious about Si2 clarity by the 2 ct mark not possibly being eye clean, or so rare that it must be vigorously analyzed by an expert. So, this general feeling also informs my thinking. I had the chance to view side by side a 1.5 ct. superideal against a 2.08 ct near ideal. The facet size of the larger diamond did out perform the smaller superideal to our eyes, so it makes me think that a 35% difference in size is visually significant to overcome performance differences. What's the minimum size difference? I'm not sure, but it probably varies depending on what makes are being compared. My guess is around 25%. Just as a side note, the smaller superideal was 10% more in cost than the 35% larger weight near ideal.

 

[pfunk]

Great discussion being had here. While this direction isn't exactly where I saw the thread going, and I still haven't seen IS images that indicate going by the numbers is a big risk, I have still enjoyed the exchanges here. I in no way judge anyone for choosing to spend as much of their budget as possible on cut and making more sacrifices to the other c's. I do, however, think consumers should know what the magnitude of visual difference will be when going from super ideal to a typical ideal proportioned stone. Is the difference as noticeable as what you will appreciate when going from a steep-deep, edge of GIA excellent stone to the zenith of gia excellent?

If the perceived beauty increases at smaller, less noticeable increments from GIA good, to VG, to excellent, to ideal excellent, to super ideal I consider it to be a diminishing benefit. If the differences begin to be hard to perceive without the aid of magnification or computers, yet they continue to increase in cost due to the labor and equipment costs involved, the value begins to go down. At least to the consumers who want to be able to SEE the difference to appreciate. I am not saying the difference isn't there, but if it's equivalent to having to loupe a stone to see an otherwise eye clean inclusion, it is more of a mind clean thing as others have stated.

Also, I don't think it is quite fair to say that you are going to always question yourself that you left something on the table if you did't get a superideal cut. It is a compromise, and cut is not standing alone above the other c's. Cut is not the only thing that contributes to what makes a person find their diamond beautiful. That's like saying you'll forever question whether you should have jumped up in color. To hint that the only way you will find true, life long satisfaction is to not sacrifice at all in cut is not accurate. And the thought that heirlooms that pass down through generations do so because they are cut with perfect precision is a stretch. What happens if cut improves even further 20 years from now as you all hope that it will? Will the superideals of 2015 be lacking in beauty then, not worthy of becoming an heirloom?

 

[pfunk]

I love this read (although my tendencies lean toward the practical aspects and less technical, but love to read). I just wanted to give my personal experience to answer a couple questions of the OP regarding size thresholds for clarity and facet size. Imho, this threshold is somewhere around 1.5 ct to 1.7 ct for both clarity and facet size, certainly by 2 ct. (7.5 mm - 8.0 mm diameter), depending on hawk eyes and definition of eye clean to what distance and side view.

I've read that many diamond sellers are very cautious about Si2 clarity by the 2 ct mark not possibly being eye clean, or so rare that it must be vigorously analyzed by an expert. So, this general feeling also informs my thinking. I had the chance to view side by side a 1.5 ct. superideal against a 2.08 ct near ideal. The facet size of the larger diamond did out perform the smaller superideal to our eyes, so it makes me think that a 35% difference in size is visually significant to overcome performance differences. What's the minimum size difference? I'm not sure, but it probably varies depending on what makes are being compared. My guess is around 25%. Just as a side note, the smaller superideal was 10% more in cost than the 35% larger weight near ideal.

Thanks for sharing this. I thought there had to be a point where facet size made an equivalent (or near equivalent) visual impact as precision faceting and alignment. I would love to see it in real life.

 

[KobiD]

Great discussion being had here. While this direction isn't exactly where I saw the thread going, and I still haven't seen IS images that indicate going by the numbers is a big risk, I have still enjoyed the exchanges here. I in no way judge anyone for choosing to spend as much of their budget as possible on cut and making more sacrifices to the other c's. I do, however, think consumers should know what the magnitude of visual difference will be when going from super ideal to a typical ideal proportioned stone. Is the difference as noticeable as what you will appreciate when going from a steep-deep, edge of GIA excellent stone to the zenith of gia excellent?

If the perceived beauty increases at smaller, less noticeable increments from GIA good, to VG, to excellent, to ideal excellent, to super ideal I consider it to be a diminishing benefit. If the differences begin to be hard to perceive without the aid of magnification or computers, yet they continue to increase in cost due to the labor and equipment costs involved, the value begins to go down. At least to the consumers who want to be able to SEE the difference to appreciate. I am not saying the difference isn't there, but if it's equivalent to having to loupe a stone to see an otherwise eye clean inclusion, it is more of a mind clean thing as others have stated.

Also, I don't think it is quite fair to say that you are going to always question yourself that you left something on the table if you did't get a superideal cut. It is a compromise, and cut is not standing alone above the other c's. Cut is not the only thing that contributes to what makes a person find their diamond beautiful. That's like saying you'll forever question whether you should have jumped up in color. To hint that the only way you will find true, life long satisfaction is to not sacrifice at all in cut is not accurate. And the thought that heirlooms that pass down through generations do so because they are cut with perfect precision is a stretch. What happens if cut improves even further 20 years from now as you all hope that it will? Will the superideals of 2015 be lacking in beauty then, not worthy of becoming an heirloom?

Well said pfunk. A great summary of what I was trying to say/demonstrate, purely from a consumers perspective. I believe this is also the main difference between our view points and the feedback we are receiving though.

We have all agreed that there is an increase in performance from ideal to super ideal (even if only subtle or only measurable through use of tools or under microscope). From a trade perspective though, there is nothing to gain by supporting the sale of lesser diamonds. It will not only reduce potential sales in the present, it also lowers the potential future standards (which are in everyones best interests). Being that cut is an aspect that is entirely controlled by the human involvement, it makes sense to use energy in this direction. Potentially, while mining diamonds very little can be done to reduce the supply of lesser colours or lower clarities, a lot can be done to in terms of striving towards higher cut standards.

I too would really like to see some reflector images of super-ideal proportioned stones which are negatively impacted through a lack or symmetry or imperfections in clarity.

 

[MelisendeDiamonds]

I disagree with that in the real world I have seen diamonds that were fics, bics, steep-deeps, shallow-shallow. and oec with high levels of 3d optical symmetry some with images that would be called h&a some not.

>>> When considering hearts images in the Modern Round Brilliant, and Ideal Hearts and Arrows images, one must be reasonably close to Tolk proportions to qualify by definition (see HRD standards). If you relax your standards to "close" to Ideal hearts and don't define what is close than the term is just a marketing one and my statement has little meaning.

I wouldn't even include an OEC, or most fancy shapes by definition as having a pattern that qualifies as Ideal hearts and arrows in an MRB. This discussion and my comments focus on the Modern Round Brilliant and not fancy shapes as that has not been the focus of this thread.

 

[Karl_K]

I disagree with that in the real world I have seen diamonds that were fics, bics, steep-deeps, shallow-shallow. and oec with high levels of 3d optical symmetry some with images that would be called h&a some not.

>>> When considering hearts images in the Modern Round Brilliant, and Ideal Hearts and Arrows images, one must be reasonably close to Tolk proportions to qualify by definition (see HRD standards). If you relax your standards to "close" to Ideal hearts and don't define what is close than the term is just a marketing one and my statement has little meaning.

I wouldn't even include an OEC, or most fancy shapes by definition as having a pattern that qualifies as Ideal hearts and arrows in an MRB. This discussion and my comments focus on the Modern Round Brilliant and not fancy shapes as that has not been the focus of this thread.

My point was because a diamond is not a tic does not mean it isn't cut with a high level of 3d optical symmetry just like it being a tic does not mean it was.
Further:
Heart and arrows is a marketing term for the images that some combos of RB show under the viewer when they have high levels of 3d optical symmetry.
Further:
An RB can have a high level of optical symmetry and not be h&a.
For example I have seen pavilion views in a heart viewer similar to this virtual model:

I have seen diamonds with similar views and it shows spot on 3d optical symmetry but not h&a.

 

[MelisendeDiamonds]

I disagree with that in the real world I have seen diamonds that were fics, bics, steep-deeps, shallow-shallow. and oec with high levels of 3d optical symmetry some with images that would be called h&a some not.

>>> When considering hearts images in the Modern Round Brilliant, and Ideal Hearts and Arrows images, one must be reasonably close to Tolk proportions to qualify by definition (see HRD standards). If you relax your standards to "close" to Ideal hearts and don't define what is close than the term is just a marketing one and my statement has little meaning.

I wouldn't even include an OEC, or most fancy shapes by definition as having a pattern that qualifies as Ideal hearts and arrows in an MRB. This discussion and my comments focus on the Modern Round Brilliant and not fancy shapes as that has not been the focus of this thread.

My point was because a diamond is not a tic does not mean it isn't cut with a high level of 3d optical symmetry just like it being a tic does not mean it was.
Further:
Heart and arrows is a marketing term for the images that some combos of RB show under the viewer when they have high levels of 3d optical symmetry.
Further:
An RB can have a high level of optical symmetry and not be h&a.
For example I have seen pavilion views in a heart viewer similar to this virtual model:

I have seen diamonds with similar views and it shows spot on 3d optical symmetry but not h&a.

Spot on 3d optical symmetry in a real cut diamond to a model in DC is impossible there will always be deviations in precision in an actual polished stone not found in the model.

Just because you provided an uncommon example doesn't disprove my statement. They are rare, and from a profitability and saleability standpoint I can't think of a good set of reasons why a cutter would deliberately and repeatedly choose to cut the rough that way.

 

[Karl_K]

Just because you provided an uncommon example doesn't disprove my statement. They are rare, and from a profitability and saleability standpoint I can't think of a good set of reasons why a cutter would deliberately and repeatedly choose to cut the rough that way.

It is what the rough supports and they have up to date equipment, skilled cutters and a mature process so it ends up with high 3d optical symmetry but not a tic.
The 3d optical symmetry of even off make diamonds has increased a lot in the almost 12 years I have been involved with diamonds.
Which is also why we are seeing a lot more h&a diamonds on the market.