New Line of Brian Gavin Signature Cushion Cuts

[delight]

http://www.briangavindiamonds.com/diamond/brian-gavin-hearts-and-arrows/

Here are a couple of examples:

http://www.briangavindiamonds.com/diamonds/diamond-details/0.661-h-vs2-cushion-diamond-ags-104065050016
http://www.briangavindiamonds.com/diamonds/diamond-details/0.716-e-si1-cushion-diamond-ags-104065050014
http://www.briangavindiamonds.com/diamonds/diamond-details/0.705-j-si1-cushion-diamond-ags-104065051017

What do you guys think of the new cuts?

 

[Paul-Antwerp]

I wonder how AGS defined the diameter-notation.

 

[chrono]

I received BGD's email on their new cushions too and wonder how they compare to GOG's H&A squares (price and cut).

 

[arkieb1]

I got the email too and was thinking oh, a GOG Brellia by any other name would smell as sweet..... sorry I couldn't resist the shakespeare.....

 

[diagem]

I wonder how AGS defined the diameter-notation.

Interesting Total Depth calculation by AGSL on this Cushion shape..., a new mathematical formula perhaps?

 

[0-0-0]

I think their H&A cushions have a much wider range of tolerances than their H&A rounds.

 

[teobdl]

I wonder how AGS defined the diameter-notation.

For the lay people to understand your question, is this different than length and width measurements?

 

[GoSounders]

I just bought one of these yesterday, after a lot of deliberation. I actually talked to Brian Gavin yesterday, and asking him questions about his cushion assuaged many of my concerns.

I was between 2 stones:
1. BGD H&A Cushion .723ct 5.07mmx5.07mm I SI2
http://www.briangavindiamonds.com/diamonds/diamond-details/0.723-i-si2-cushion-diamond-ags-104065051018
2. GOG Brellia Cushion .718ct 5.07x5.08 I SI1
http://www.goodoldgold.com/diamond/11076/

Why I went with the BGD:
1. $500 (20%) less for effectively the same stone except 1 grade decrease in clarity (both AGS certed)
2. Brellia's girdle gets extremely thick on the sides. This seems to be done on purpose, but I liken this to "painting" the girdle.

Why I might have gone with the Brellia:
1. It's been around longer
2. Lots of videos showing the Brellia's performance in different environments, and it does extremely well in all of them.
3. GOG's detailed photos and analytics

I should be getting my stone next week, so I'll be posting pictures here when I do.

Edit: Re: dimensions, I forgot to ask BG about the first number being the diagonal, but I'm fairly sure this is the case.

 

[Todd Gray]

The dimensions are tip to tip.

 

[diagem]

The dimensions are tip to tip.

Hi Todd, nice seeing you on the boards..., since you mention evaluation, tip to tip from a gemological stand-point?

 

[Lula]

They look great. Congratulations to BGD. It's nice to have another vendor option for square H&As. Congratulations on your purchase, GoSounders. You saved yourself some serious $$ Please post photos when you get your ring!

 

[Todd Gray]

The dimensions are tip to tip.

Hi Todd, nice seeing you on the boards..., since you mention evaluation, tip to tip from a gemological stand-point?

Diagonally "X" across the diamond from "tip to tip" as demonstrated on the attached graphic. This represents the true diameter of the diamond, Paul Sleger's PS article https://www.pricescope.com/journal/numbers_and_perception_case_square_diamondcuts will provide some insight to this regard.

Regarding the Brellia, I haven't seen it yet, but I'd be happy to do a side-by-side comparison of the two variations of H&A Cushions if a Brellia vendor would like to send me one for evaluation, perhaps we can post the findings on PS as a Knowledge article. One thing that I notice when looking at the video of the diamond presented on the front page of the Brellia web site, is that it appears to have an extremely thick girdle, this is not the case with the BGD Signature Cushion, which has a girdle edge which is not that noticeable. And if you look at the plotting diagrams provided on the lab reports, the facet design of the two diamonds is clearly different.

I think it is important to note that there are always going to be variations of diamond design, and there is always going to be room for improvement. Take the princess cut diamond for example, there are several different "standard" facet designs for the square brilliant cut diamond, each has it's advantages and disadvantages, and each will produce different types of light return, sparkle factor, etc., and as such, will appeal to different markets. One thing which I think is very cool about this diamond, is that it gets an overall cut grade of AGS Ideal-0 from the AGSL, it's not easy to do.

 

[OMG_AMG]

it is also important to note that the BGD H&A cushions are classified as cushion modified brilliants, and I suspect it is because the 8 thin pavilion facets do not extend all the way out to the girdle (according to the facet plot)

GOG Brellia's are all classified as cushion brilliants, and their 8 thin pavilion facets extend all the way out to the girdle

also, like others have mentioned, the girdle on the Brellia's are indeed thicker than the BGD H&A cushions

as far as I can tell, the dimensions in regards to carat size are the same for both types of cushions...however, the Brellia's are using a length x width dimension formula whereas the BGD H&A cushions are using a diagonal x width formula

Both should give excellent light return, althrough I suspect the BGD H&A cushions will be cheaper in price

 

[diagem]

Diagonally "X" across the diamond from "tip to tip" as demonstrated on the attached graphic. This represents the true diameter of the diamond, Paul Sleger's PS article https://www.pricescope.com/journal/numbers_and_perception_case_square_diamondcuts will provide some insight to this regard.

Are AGSL graded princess cuts (Modified Square's) also measured by their true diameter (e.g. Tip to tip diagonally)??

 

[Paul-Antwerp]

The dimensions are tip to tip.

Hi Todd, nice seeing you on the boards..., since you mention evaluation, tip to tip from a gemological stand-point?

Diagonally "X" across the diamond from "tip to tip" as demonstrated on the attached graphic. This represents the true diameter of the diamond, Paul Sleger's PS article https://www.pricescope.com/journal/numbers_and_perception_case_square_diamondcuts will provide some insight to this regard.
Regarding the Brellia, I haven't seen it yet, but I'd be happy to do a side-by-side comparison of the two variations of H&A Cushions if a Brellia vendor would like to send me one for evaluation, perhaps we can post the findings on PS as a Knowledge article. One thing that I notice when looking at the video of the diamond presented on the front page of the Brellia web site, is that it appears to have an extremely thick girdle, this is not the case with the BGD Signature Cushion, which has a girdle edge which is not that noticeable. And if you look at the plotting diagrams provided on the lab reports, the facet design of the two diamonds is clearly different.

I think it is important to note that there are always going to be variations of diamond design, and there is always going to be room for improvement. Take the princess cut diamond for example, there are several different "standard" facet designs for the square brilliant cut diamond, each has it's advantages and disadvantages, and each will produce different types of light return, sparkle factor, etc., and as such, will appeal to different markets. One thing which I think is very cool about this diamond, is that it gets an overall cut grade of AGS Ideal-0 from the AGSL, it's not easy to do.

Hi Todd,

I am sorry, but I must correct you on two counts.

1. I just opened the details of the 0.716, and the diameter measurements are 6.10 x 5.05. Now, one of those may be tip-to-tip, but I am quite sure the other is not.

2. If you read my article about diameter-notation correctly, tip-to-tip only is not a true representation of the diameter of a diamond. It is in fact an exaggeration.

Following problem becomes: what diameter has been used to calculate depth-percentages, ranging from total depth, crown height, pavilion depth to girdle thickness? Where the traditional notation of diameter in fancy shapes creates negative psychological effects, I find this attempt confusing from the outset. I do not like it all.

Live long,

 

[GoSounders]

Hi Todd,

I am sorry, but I must correct you on two counts.

1. I just opened the details of the 0.716, and the diameter measurements are 6.10 x 5.05. Now, one of those may be tip-to-tip, but I am quite sure the other is not.

2. If you read my article about diameter-notation correctly, tip-to-tip only is not a true representation of the diameter of a diamond. It is in fact an exaggeration.

Following problem becomes: what diameter has been used to calculate depth-percentages, ranging from total depth, crown height, pavilion depth to girdle thickness? Where the traditional notation of diameter in fancy shapes creates negative psychological effects, I find this attempt confusing from the outset. I do not like it all.

Live long,

This is indeed very confusing. Just having the side-to-side dimensions would make the stone seem smaller than it is, since it would be ignoring the extra size in the corners. Having the two diagonal lengths would make the stone seem larger than it is, since it would ignore the sides that have been cut away compared to a round. Thus, they went with the more confusing, but more informative notation for tip-to-tip length x side-to-side length.

Looking at the AGS cert, it gets even more confusing. The graphic for the side profile is looking right at the side, which it labels as 100%. However, the total depth, when you crunch the numbers, is not based on that 100% side length. It's based on the diagonal tip-to-tip distance. The crown and pavilion percentages are likely also based on the diagonal tip-to-tip distance, as they add up almost to the total depth %, with a small bit left over for the girdle. Without a Sarin or other facet tool, there's no telling where they got the table % from. They might use the side length to make the table seem larger.

 

[Paul-Antwerp]

Having slept over this, I have done some comparative research, and I can now explain more in detail the potential ramifications. At first, I was confused, now I think that I understand. I am sorry if this is going to be a long post. Also sorry if this may sound a bit cranky. In this being about cushions, I have no interest since I am not producing such shape, nor intend to, but it touches aspects of consumer-confidence, indirectly into my own product.

With AGSL being an integral part of our own brand, it is disappointing to see how they confuse the public in the area of branded cushions.

Here is example 1, a BGD cushion, weighing 0.716 Ct. : http://www.briangavindiamonds.com/d...nd-ags-104065050014#!prettyPhoto[gallery2]/0/.

The measurement-notation is 6.10 x 5.05 x 3.57 mm., with 3.57 mm being the depth-measurement. With the stone being presumably square, my educated guess is that 6.10 mm stands for the longest tip-to-tip-measurement and 5.05 mm for the shortest side-to-side-measurement.

The convention for gemological lab-reports is for fancy shapes to note the smallest and the biggest side-to-side-measurement. I have long ago argued that this convention in fact makes fancy shapes appear (psychologically) smaller than they actually are, but I never found or defended a better option.

Let us compare to example 2, a GOG cushion, weighing 0.718 Ct: http://www.goodoldgold.com/show.php?image=11076/ags.jpg

Here the measurement-notation is 5.08 x 5.07 x 3.60 mm. Do note that both reports come from the same lab. One shape being called Cushion Brilliant, the other Cushion Modified Brilliant has in my opinion no effect on how we read measurements.

It is clear that AGSL uses one system for BGD, another for GOG (the conventional system for fancy shapes). I am very sorry, but if you do not find this confusing, what is? I can only imagine, if both brands become popular here on PS, the multitude of threads asking to clarify this difference, and the difficulty for prosumers to correctly answer this, without casting confusion about diamonds in general and AGSL in particular.

The BGD-system has the advantage of highlighting the diagonal tip-to-tip-diameter, but imagine showing this report to a B&M-retailer, telling him that this is the square stone you are considering. Almost any B&M-retailer, not following this specific thread will look at 6.10x5.05x3.57, and say, based upon gemological convention: "Square? This is not square. The stone has a length-to-width-ratio of 1.21." Is he wrong? Yes. Can he blamed for being wrong? No, he just reads the information on the lab-report, and upon gemological convention, that is what the report says. Imagine how time-consuming it will be for PS to correct the confusion here, if that consumer asks this in a thread.

And still, the question for the consumer remains: is this diamond square? In reality, with this notation, one simply does not know.

Comparing the BGD-stone with the GOG-stone, same weight of 0.71, one has a diameter of 6.10x5.05x3.57 versus 5.08x5.07x3.60. Stone A apparently has a much larger surface-area, which seems a competitive advantage. In reality however, they probably have almost the same surface. Imagine the number of threads on PS, that will need to clarify this.

It goes further. Note the mm-depth, one being 3.57 mm, the other 3.60 mm. On the GOG-stone, this translates, according to gemological convention, to a total depth of 71.1% (in fancy shapes, total depth compared to smallest diameter). On the BGD-stone, practically the same mm-measurement suddenly leads to a total depth calculation of 58.6%. Doing the maths, it appears that this calculation is suddenly total depth compared to longest (tip-to-tip) diameter, 3.57/6.10 = 58.6%). AGSL, what are you doing to us?

Imagine how often a neophyte prosumer on PS will post: "See, that BGD-stone has a depth of 58.6%, compared to 71.1% for GOG, so the GOG-stone is cut-for-weight, and hiding unnecessary depth compared to diameter." It is getting annoying, but imagine the energy needed to correct this constantly on the forum.

I must admit, I carry a bit of responsibility in this. Long ago, when discussing princess-cuts and fancy shapes in general, I have raised the problem that it is unfair to fancy shapes that the gemological conventional notation is different to that of rounds, thus making fancy shapes look smaller in a direct comparison. However, I have not, to my memory, suggested a solution to this, and surely, what is used here is a bad solution to the problem.

I apologize too, if this post sounds cranky or negative. The thing is: it makes me angry. With me having no commercial interest in cushion-shapes, it should probably leave me indifferent. But here you have AGSL, who I regard as a top-lab, using two different methods on probably highly comparable stones. This is not what I expect from a lab, destined to consumer-protection. And every time that it leads to inevitable consumer-confusion, that needs to be corrected, it will reflect badly upon AGSL, creating the confusion. And us, using AGSL-reports for other shapes, will have to deal with a lab-report, of which reliability comes under question.

I am very sorry, but I cannot help being angry here. With all the good intentions, this is only leading to confusion and more confusion. I am very, very disappointed by such example of irresponsibility.

Live long,

 

[Karl_K]

Well said Paul, I feel the same way.
If they want to put tip to tip on a report they need to make it a separate line item and keep the derived measurements(depth, table etc.) the same as any other cushion report.
To mix the measurements like they have done is frankly insane and wrong.

 

[chrono]

When I took a quick look, I was definitely taken in by the apparent lower depth percentage of 60% thereabouts listed for the BGD cushion and wondered "wow, this is shallower than most other cushions, both branded and unbranded". Certainly unintentionally misleading at first glance.

 

[teobdl]

Here is a fairly simple solution, which could be used for all 4-sided stones...

1. Diagram face up view: 2 side lengths (both max and min) and both diagonals. This gives a sense of shape and symmetry.
2. Diagram profile view with measurements showing depth and the side that's used for depth % calculation. This clears up confusion about depth dimensions. They'd need to decide on a convention of [depth mm] / [longest side mm OR shortest side mm].

 

[GoSounders]

Here is a fairly simple solution, which could be used for all 4-sided stones...

1. Diagram face up view: 2 side lengths (both max and min) and both diagonals. This gives a sense of shape and symmetry.
2. Diagram profile view with measurements showing depth and the side that's used for depth % calculation. This clears up confusion about depth dimensions. They'd need to decide on a convention of [depth mm] / [longest side mm OR shortest side mm].

#2 should exist already, except the 100% side that's called out on the diagram isn't the side that is used for the depth %. At least with the depth, one can easily calculate based on the information given. Table % is anyone's guess.

The simplest solution (and your #1 touches on this) would be to keep every major bit of information/calculation the same as every other cushion that's been AGS certed for the last 17 years, and simply add extra information separately as needed. Changing things will only lead to confusion.

 

[yssie]

Paul, that was a fantastically eloquent post that highlights precisely the sorts of problems we consumers will run into.

I've given up on trying to keep up with AGSL's ongoing identity crisis. First there are the reports themselves - it's a veritable alphabet soup: DQRs with Light Performance for proprietary and non-proprietary shapes, DQDs with Light Performance for proprietary and non-proprietary shapes, DQRs without Light Performance for non-proprietary shapes...

Then there are the not-infrequent changes in reporting schemas - so we've got the modern Platinum DQD with Light Performance for non-proprietary shapes that uses one set of cut grade metrics, the older DQD without Light Performance, the modern Gold DQR without Light Performance for non-proprietary shapes that uses a different set of cut grade metrics but confusingly similar grading nomenclature, the DQR for non-proprietary shapes that doesn't issue a cut grade at all, a handful of other DXs that serve other niche needs...

And now they've introduced this new oddity. Which is actually IMO even more insiduous - you truly wouldn't catch it unless you were inspecting both reports with calculator in-hand! I can see value in and problems with reporting both types of dimensions - 5.08x5.07 tells me that the stone looks like a square but doesn't tell me anything about the roundedness of the corners; 6.10x5.05 tells me that assumning the stone is almost square the arc the corners make clips ~0.5mm off the 'virtual diagonal' that would've resulted had the straight sides extended to meet at 'virtual corners' but doesn't tell me if my assumption of a square stone is valid.

Why not just just draw three lines across the plot diagram to indicate where the numbers are coming from? Or better, pick a scheme - ONE scheme - and stick with it!

ETA: and my 2c on the actual topic - the stones look gorgeous

 

[diagem]

Having slept over this, I have done some comparative research, and I can now explain more in detail the potential ramifications. At first, I was confused, now I think that I understand. I am sorry if this is going to be a long post. Also sorry if this may sound a bit cranky. In this being about cushions, I have no interest since I am not producing such shape, nor intend to, but it touches aspects of consumer-confidence, indirectly into my own product.

With AGSL being an integral part of our own brand, it is disappointing to see how they confuse the public in the area of branded cushions.

Here is example 1, a BGD cushion, weighing 0.716 Ct. : http://www.briangavindiamonds.com/d...nd-ags-104065050014#!prettyPhoto[gallery2]/0/.

The measurement-notation is 6.10 x 5.05 x 3.57 mm., with 3.57 mm being the depth-measurement. With the stone being presumably square, my educated guess is that 6.10 mm stands for the longest tip-to-tip-measurement and 5.05 mm for the shortest side-to-side-measurement.

The convention for gemological lab-reports is for fancy shapes to note the smallest and the biggest side-to-side-measurement. I have long ago argued that this convention in fact makes fancy shapes appear (psychologically) smaller than they actually are, but I never found or defended a better option.

Let us compare to example 2, a GOG cushion, weighing 0.718 Ct: http://www.goodoldgold.com/show.php?image=11076/ags.jpg

Here the measurement-notation is 5.08 x 5.07 x 3.60 mm. Do note that both reports come from the same lab. One shape being called Cushion Brilliant, the other Cushion Modified Brilliant has in my opinion no effect on how we read measurements.

It is clear that AGSL uses one system for BGD, another for GOG (the conventional system for fancy shapes). I am very sorry, but if you do not find this confusing, what is? I can only imagine, if both brands become popular here on PS, the multitude of threads asking to clarify this difference, and the difficulty for prosumers to correctly answer this, without casting confusion about diamonds in general and AGSL in particular.

The BGD-system has the advantage of highlighting the diagonal tip-to-tip-diameter, but imagine showing this report to a B&M-retailer, telling him that this is the square stone you are considering. Almost any B&M-retailer, not following this specific thread will look at 6.10x5.05x3.57, and say, based upon gemological convention: "Square? This is not square. The stone has a length-to-width-ratio of 1.21." Is he wrong? Yes. Can he blamed for being wrong? No, he just reads the information on the lab-report, and upon gemological convention, that is what the report says. Imagine how time-consuming it will be for PS to correct the confusion here, if that consumer asks this in a thread.

And still, the question for the consumer remains: is this diamond square? In reality, with this notation, one simply does not know.

Comparing the BGD-stone with the GOG-stone, same weight of 0.71, one has a diameter of 6.10x5.05x3.57 versus 5.08x5.07x3.60. Stone A apparently has a much larger surface-area, which seems a competitive advantage. In reality however, they probably have almost the same surface. Imagine the number of threads on PS, that will need to clarify this.

It goes further. Note the mm-depth, one being 3.57 mm, the other 3.60 mm. On the GOG-stone, this translates, according to gemological convention, to a total depth of 71.1% (in fancy shapes, total depth compared to smallest diameter). On the BGD-stone, practically the same mm-measurement suddenly leads to a total depth calculation of 58.6%. Doing the maths, it appears that this calculation is suddenly total depth compared to longest (tip-to-tip) diameter, 3.57/6.10 = 58.6%). AGSL, what are you doing to us?

Imagine how often a neophyte prosumer on PS will post: "See, that BGD-stone has a depth of 58.6%, compared to 71.1% for GOG, so the GOG-stone is cut-for-weight, and hiding unnecessary depth compared to diameter." It is getting annoying, but imagine the energy needed to correct this constantly on the forum.

I must admit, I carry a bit of responsibility in this. Long ago, when discussing princess-cuts and fancy shapes in general, I have raised the problem that it is unfair to fancy shapes that the gemological conventional notation is different to that of rounds, thus making fancy shapes look smaller in a direct comparison. However, I have not, to my memory, suggested a solution to this, and surely, what is used here is a bad solution to the problem.

I apologize too, if this post sounds cranky or negative. The thing is: it makes me angry. With me having no commercial interest in cushion-shapes, it should probably leave me indifferent. But here you have AGSL, who I regard as a top-lab, using two different methods on probably highly comparable stones. This is not what I expect from a lab, destined to consumer-protection. And every time that it leads to inevitable consumer-confusion, that needs to be corrected, it will reflect badly upon AGSL, creating the confusion. And us, using AGSL-reports for other shapes, will have to deal with a lab-report, of which reliability comes under question.

I am very sorry, but I cannot help being angry here. With all the good intentions, this is only leading to confusion and more confusion. I am very, very disappointed by such example of irresponsibility.

Live long,

Hi Paul, am I happy you slept over this paradox.
As this subject can't be more relevant to my Cushion works I must comunicate humbly & gently...
I thought for a moment I was the only one noticing the miss-representation of the potential surface area numbers, as a side observer it would seem to me AGSL started offering tailor-made proprietors cut grading reports?
Surprising and disappointing indeed?

 

[Garry H (Cut Nut)]

There is only one way to refer to spread, and AGS use it in calculations for rounds only. it should be used for all cuts if we are really serious about " labs are for consumer confidence".
All shapes and cuts should be compared to a single round cut standard. Full stop.

 

[Todd Gray]

Paul, I believe that I fully understand where you are coming from, because I too was initially confused when I first took a look at the diamond which Brian Gavin sent me for evaluation, because it looked square and the measurements on the AGS Diamond Quality Document gave me the impression that the diamond would be slightly rectangular.

Rather than guess as to how the diamond was being measured, I simply called Brian Gavin and asked him, he explained that there were several diamonds in this classification of cut style which were being measured this way, specifically, the Ideal2 and the Princess of Hearts. Thus it seems like there is precedence for this diamond to be measured this way...

Arguably, it might make more sense for Asscher cut diamonds, Princess cut diamonds, and Radiant cut diamonds to be measured this way, because it provides a better representation of the surface area of the diamond, than measuring such diamonds from edge to edge provides. However this is not how any of us were taught to measure diamonds... but that is not to say that it is not a valid method of measurement. My understanding is that the AGSL has been measuring diamonds like this since 2001, so it's not exactly a new concept.

At the end of the day, while this method of measurement might present some confusion to the retail trade, it has nothing to do with the visual properties of the diamond, and I think that it is unfortunate that the introduction of a new cut is being met with challenges as to how it is being measured, rather than being considered for its light return and visual performance... but perhaps this is because I'm the only person on this thread who has actually seen the diamond thus far, I'm sure that Brian would send one to you if you'd like to check it out.

I don't really want to get into a long-winded debate about the diameter of a circle, the diameter of a square, how to establish boundaries for the purpose of calculating surface area, etc., because it isn't going to change how this diamond is being measured, nor will it change how the Ideal2, or the Princess of Hearts is being measured; the simple fact is that they are being measured this way, and as long as they are all being measured in similar fashion, people can use the data provided on the DQD to make a comparison... to the extent that they can be compared, since all three of them are proprietary cuts with different facet designs and structures. Laughs.

I have to say that I'm disappointed about one thing... there was a time, not so long ago, that the introduction of a new cut, would have been met with excitement and intrigue on this forum, not immediately torn apart because nobody can figure out how it is being measured. I don't see the Ideal2, or the Princess of Hearts, being shredded for how it is being measured, maybe I just missed those posts. Would anybody care to share those with me?

And finally I just want to point out, I'm not trying to argue with Paul, or anybody else, about how this diamond is being measured... I merely responded to the question about what the measurements represented, because I knew the answer. Honestly I'm not sure anymore whether this is a thread about a new diamond cut, or how the AGSL is measuring diamonds. Perhaps this is one of those debates which we should have out on Pollard's back deck, over a beer and some barbecue, because I don't think it's going to be solved here, we can invite Brian over from Houston, I'll fly in from California, Peter can fly in from Vegas, Paul can fly in from Antwerp, and Garry can fly in from Australia (I'll bring him some wine) and I'm going to kick back and watch y'all hash this out, because that will at least remind me of the good old days when everybody would have just been excited that one of us had introduced a new cut, and it gives me an excuse to wolf down some of great food with good friends

 

[diagem]

I have to say that I'm disappointed about one thing... there was a time, not so long ago, that the introduction of a new cut, would have been met with excitement and intrigue on this forum, not immediately torn apart because nobody can figure out how it is being measured. I don't see the Ideal2, or the Princess of Hearts, being shredded for how it is being measured, maybe I just missed those posts. Would anybody care to share those with me?

Where was this "new" cut introduction torn apart Todd? I believe the focus is on AGSL's swaying of measurement known methods.
I never noticed about the other examples you have mentioned and still it doesn't make their differentiations between the two proprietors Cushion cuts (mentioned above by Paul) any more correct. It's clear it's the opposite..., more confusing to all.

These kind of accusations make us keep out of these conversations.

 

[diagem]

There is only one way to refer to spread, and AGS use it in calculations for rounds only. it should be used for all cuts if we are really serious about " labs are for consumer confidence".
All shapes and cuts should be compared to a single round cut standard. Full stop.

Why round and not square Garry? Because of the majority?
I don't see any logic comparing a Marquise or Pears and similar spreads to round...

 

[teobdl]

There is only one way to refer to spread, and AGS use it in calculations for rounds only. it should be used for all cuts if we are really serious about " labs are for consumer confidence".
All shapes and cuts should be compared to a single round cut standard. Full stop.

I agree that there theoretically should be a standardized measure, but I'm not sure that making the average diameter of a diamond the denominator (as they do with rounds) is the solution. What about emerald cuts and ovals and marquis and pears and other shapes that weren't intended to be perfectly round or square? As a consumer, the depth percentage even within the same fancy shape would be nearly meaningless.

For all modified shapes, AGS just needs to be clear about what's being measured. The first thing I want to know is how big the thing is, and that's impossible if I don't know what's being measured. Just put a diagram on the lab report like the one Todd Gray made and the problem is solved.

 

[WinkHPD]

Paul, I believe that I fully understand where you are coming from, because I too was initially confused when I first took a look at the diamond which Brian Gavin sent me for evaluation, because it looked square and the measurements on the AGS Diamond Quality Document gave me the impression that the diamond would be slightly rectangular.

Rather than guess as to how the diamond was being measured, I simply called Brian Gavin and asked him, he explained that there were several diamonds in this classification of cut style which were being measured this way, specifically, the Ideal2 and the Princess of Hearts. Thus it seems like there is precedence for this diamond to be measured this way...

Arguably, it might make more sense for Asscher cut diamonds, Princess cut diamonds, and Radiant cut diamonds to be measured this way, because it provides a better representation of the surface area of the diamond, than measuring such diamonds from edge to edge provides. However this is not how any of us were taught to measure diamonds... but that is not to say that it is not a valid method of measurement. My understanding is that the AGSL has been measuring diamonds like this since 2001, so it's not exactly a new concept.

At the end of the day, while this method of measurement might present some confusion to the retail trade, it has nothing to do with the visual properties of the diamond, and I think that it is unfortunate that the introduction of a new cut is being met with challenges as to how it is being measured, rather than being considered for its light return and visual performance... but perhaps this is because I'm the only person on this thread who has actually seen the diamond thus far, I'm sure that Brian would send one to you if you'd like to check it out.

I don't really want to get into a long-winded debate about the diameter of a circle, the diameter of a square, how to establish boundaries for the purpose of calculating surface area, etc., because it isn't going to change how this diamond is being measured, nor will it change how the Ideal2, or the Princess of Hearts is being measured; the simple fact is that they are being measured this way, and as long as they are all being measured in similar fashion, people can use the data provided on the DQD to make a comparison... to the extent that they can be compared, since all three of them are proprietary cuts with different facet designs and structures. Laughs.

I have to say that I'm disappointed about one thing... there was a time, not so long ago, that the introduction of a new cut, would have been met with excitement and intrigue on this forum, not immediately torn apart because nobody can figure out how it is being measured. I don't see the Ideal2, or the Princess of Hearts, being shredded for how it is being measured, maybe I just missed those posts. Would anybody care to share those with me?

And finally I just want to point out, I'm not trying to argue with Paul, or anybody else, about how this diamond is being measured... I merely responded to the question about what the measurements represented, because I knew the answer. Honestly I'm not sure anymore whether this is a thread about a new diamond cut, or how the AGSL is measuring diamonds. Perhaps this is one of those debates which we should have out on Pollard's back deck, over a beer and some barbecue, because I don't think it's going to be solved here, we can invite Brian over from Houston, I'll fly in from California, Peter can fly in from Vegas, Paul can fly in from Antwerp, and Garry can fly in from Australia (I'll bring him some wine) and I'm going to kick back and watch y'all hash this out, because that will at least remind me of the good old days when everybody would have just been excited that one of us had introduced a new cut, and it gives me an excuse to wolf down some of great food with good friends

Todd,

What am I, chopped liver that you suddenly leave me out of these discussions? I, your roomy at so many of these discussions?

Sigh.

For what it is worth, the AGS laboratory has worked with people who have patented a new cut to measure them as they wish them measured for ten or twelve years now. They figure that the people who invented the cuts know how they want them measured. Seems reasonable to me.

I have no dog in this fight, other than to say that I think the new stone looks very nice and I applaud Brian for spending the many tens of thousands of dollars necessary to come up with it. I hope it works for him.

Wink

P.S. Being from Idaho I will bring the potatoes...

 

[Todd Gray]

I have to say that I'm disappointed about one thing... there was a time, not so long ago, that the introduction of a new cut, would have been met with excitement and intrigue on this forum, not immediately torn apart because nobody can figure out how it is being measured. I don't see the Ideal2, or the Princess of Hearts, being shredded for how it is being measured, maybe I just missed those posts. Would anybody care to share those with me?

Where was this "new" cut introduction torn apart Todd? I believe the focus is on AGSL's swaying of measurement known methods.
I never noticed about the other examples you have mentioned and still it doesn't make their differentiations between the two proprietors Cushion cuts (mentioned above by Paul) any more correct. It's clear it's the opposite..., more confusing to all.

These kind of accusations make us keep out of these conversations.

I also believe that this post has turned into a discussion about whether the method by which the AGSL is measuring this diamond, but is that what the thread was intended to be? The title of the post reads "New Line of Brian Gavin Signature Cushion Cuts" and the thread immediately becomes a discussion about the measurements of the diamond, and how they are incorrect and misleading. It seems to me, that the nature of discussion would make more sense had the original post been titled "How did the AGSL derive the measurements for the new Brian Gavin Cushion Cut Diamond?