A cut above vs regular cut

[GT-101]

Hi all,

Looking to purchase an engagement ring for my girlfriend - looking for a princess cut, 1ct, d-f, and ideally vs2 but willing to go down to si1 .

I've tried doing my research before posting but was not able to find an answer. I've been to many local jewelers but they don't have any ACA or ideal cut - only very good and excellent cut. I've been in touch with Whiteflash and am intrigued as to what they offer but just wanted to see what will look better an lower color and grade that's ACA or will and excellent cut with higher color and clarity be the same or better.

My budget is $5000 usd for the diamond and so far the best one I've found at WF is:

http://www.whiteflash.com/loose-diamonds/princess-cut-loose-diamond-3081021.htm

I'm concerned with color as I would like to stay in the d-f and it seems to have many inclusions.

At a local diamond wholesaler, I found the following:

1.06 Cart
F Color
vs2
depth 73.8%
table 73%
girdle STK
GIA cert
5.55 x 5.53 x 4.08
Polish: very good
Symmetry: very good
$4950

Just wanted to see ACA are definitely work compromising on color/clarity. Also, WF rings are much more expensive than what local jewelers will charge here. Any input is greatly appreciated!!

Thank you.

 

[PintoBean]

Hello,

At first blush, this isn't an apples to apples comparison. For example, the WF-ACA is ideal in polish and symmertry, while the other diamond is Very Good in polish and symmetry.

Also, will the wholesaler provide the same amount of data on the diamond, such as an Idealscope and Aset?
Have you compared return policies and upgrade policies?

These are just some things off the top of my head to keep in mind

 

[PintoBean]

Throwing in a BGD Princess Ideal cut for consideration.

http://www.briangavindiamonds.com/diamonds/diamond-details/0.965-g-si1-princess-diamond-ags-104079916002


Also, I would recommend reaching out to ID Jewelry. My friend had a budget of $5,000 and went to ID Jewelry and had a great experience. He ended up with a halo'd triple excellent princess cut over 1 carat, under budget. Unfortunately, I don't remember the rest of the specs... ID Jewelry is a great at getting you the most bang for your buck.

 

[GT-101]

The wholesaler did not have either but they do offer buy-back. A friend of mine bought from them and was very happy. They also free lifetime cleaning and inspection which being local we can take advantage of. I really like WF but wanted to know if the idealx3 would look/shine better? I've just never seen one in person.

 

[John P]

I've been to many local jewelers but they don't have any ACA or ideal cut - only very good and excellent cut.

Are these cut-grades? Or just polish and symmetry grades? If you're looking at GIA reports they make no judgment about the cut of a princess, and polish/symmetry imply nothing about the performance of the diamond.

Example:

At a local diamond wholesaler, I found the following:

1.06 Cart
F Color
vs2
depth 73.8%
table 73%
girdle STK
GIA cert
5.55 x 5.53 x 4.08
Polish: very good
Symmetry: very good

This is not "very good cut." It's VG in polish, and VG in meet-point symmetry. No information about cut. And, as mentioned, no GIA report grades the overall cut of a princess. AGSL is the only grading lab with a meaningful cut-grade for the princess shape.

Most of the world's princess cuts are not sent to AGSL, in part because GIA is considered the big dog. But also, because AGSL enforces an actual cut-grade based on performance...and the vast majority of the world's princess cuts won't pass muster there.

 

[PintoBean]

That's great that your friend is happy, but I get the feeling that you are here so that when you make your purchase, you know that you learned about all your options out there, and weighed them carefully.

Plenty of jewelry stores offer free cleaning services to get you in the door. Don't let that sway you

Yes, an ideal cut will sparkle like mad! We thought my mom's original e-ring looked nice. Then she got her first Brian Gavin ideal cut, and it makes her original diamond look static. It is blinding the way it sparkles and dances. If this makes sense, ideal cut diamonds to my eyes are dynamic. THey don't quit performing!

 

[GT-101]

You are correct, I was provided the GIA report. And from what I have read the cut is the most important factor; the ACA diamond would be the better choice, correct?

 

[John P]

If you purchase from a company which permits you an inspection-and-return period you can compare them head to head.

 

[PintoBean]

An ACA would be a great choice, but not this one - the G-SI2 because it is not indicated to be eye clean.

How about this ACA?
http://www.whiteflash.com/loose-diamonds/princess-cut-loose-diamond-2978548.htm

 

[PintoBean]

I like this one! But it's $40 over budget

http://www.jamesallen.com/loose-diamonds/princess-cut/1.01-carat-h-color-vs1-clarity-sku-394148

 

[GT-101]

Thank you for all the feedback - it is very appreciated!! Yes I wanted to do some of my own research as many people recommended me to their "diamond guy".

I was hoping to stay in the colorless range but this definitely has less inclusions. Thanks you for pointing out that the other one was not eye clean - I missed that one!!

I think I'm quite sure I will be going ahead with ACA.

Thank you.

 

[mns12]

I don't have any experience with princess cut but I can tell you that my original ER was a MRB H, SI2, "very good" cut from a local jeweler. I know have a WF ACA, I, VS and there is no comparison!! This stone is a better performer all around...sparkle, fire, crispness, symmetry, etc.!

 

[GT-101]

Awesome, that is good to hear!! Thank you!

 

[Rockdiamond]

I agree with part of what John wrote- many princess cuts on the market are very poorly cut.
However, of the well cut stones that are on the market, not all are sent to AGSL.
Unlike the cut grades for round diamonds, which enjoy broad support, the cut grades for princess cuts are not as widely accepted.
Therefore some of the best cut princess cuts are sent to GIA due to differences in opinion what constitutes the best cut in princess cut.

 

[Texas Leaguer]

I agree with part of what John wrote- many princess cuts on the market are very poorly cut.
However, of the well cut stones that are on the market, not all are sent to AGSL.
Unlike the cut grades for round diamonds, which enjoy broad support, the cut grades for princess cuts are not as widely accepted.
Therefore some of the best cut princess cuts are sent to GIA due to differences in opinion what constitutes the best cut in princess cut.

The reason the AGSL cut grade for princess cuts "are not as widely accepted" is because of economics, not beauty. Very few cutters are willing to spend the resources necessary to cut to the strict standards required to make an AGS0 princess, or to sacrifice the extra weight necessary to do so. It is easier to go with the status quo of cutting mediocre princesses with GIA reports that do not provide an overall cut grade or reveal deficits in light performance.

Someone once used the analogy here that because McDonalds sells alot more quarter pounders than Mortons sells steaks, does not mean quarter pounders are a tastier meal!

 

[Rockdiamond]

Bryan- you're making very wide, and misleading assumptions.
You can't speak for cutters.
You ( or AGSL) also can't dictate what is and is not beauty.
We agree that the finest cutters comprise a small percentage of all cutters.
But some of these ( the best cutters) do not agree with AGSL standards- for reasons of beauty.
There may be cases where MORE weight is retained on an AGSL zero compared to a very well cut GIA graded stone.

At the end of the day, the cutter only makes money when the diamond is sold and paid for.
Cutting a prettier stone brings a higher price, and quicker sale.
The AGSL look is very nice- but not for everyone.

 

[Texas Leaguer]

Bryan- you're making very wide, and misleading assumptions.
You can't speak for cutters.
You ( or AGSL) also can't dictate what is and is not beauty.
We agree that the finest cutters comprise a small percentage of all cutters.
But some of these ( the best cutters) do not agree with AGSL standards- for reasons of beauty.
There may be cases where MORE weight is retained on an AGSL zero compared to a very well cut GIA graded stone.

At the end of the day, the cutter only makes money when the diamond is sold and paid for.
Cutting a prettier stone brings a higher price, and quicker sale.
The AGSL look is very nice- but not for everyone.

I see. So I can't speak for cutters but you can??

Nobody is dictating beauty. A cut grade of AGS Ideal does not in and of itself mean a diamond is beautiful. Nor does GIA EX or a perfect hearts and arrows image or even the fact that a diamond might be D in color or FL in clarity. Beauty is a personal perception based upon all the characteristics of the diamond.

AGS 0 simply means that it does not have deficits in light performance from a cutting standpoint based upon a sophisticated ray trace of the 3D model of the actual diamond. The process is explained in detail here:
https://www.pricescope.com/journal/ags-laboratories-diamond-cut-grading-princess-cut

 

[Rockdiamond]

Hi Bryan, I am not speaking for cutters- but I do routinely speak with cutters.
Some of whom feel that AGSL standards don't produce the prettiest princess cut.

How is "light performance" not subjective?
Basically what you ( or AGSL) might consider a "deficit" in light performance, others will consider an asset.

 

[Texas Leaguer]

Hi Bryan, I am not speaking for cutters- but I do routinely speak with cutters.
Some of whom feel that AGSL standards don't produce the prettiest princess cut.

How is "light performance" not subjective?
Basically what you ( or AGSL) might consider a "deficit" in light performance, others will consider an asset.

The AGSL light performance grading system is "not subjective" in that it is a consistent, repeatable, mathematical analysis of light behavior of the individual diamond, assessing the contributions of every facet. The grade is not dependent on a grader declaring "in my opinion this is the prettiest cut".

How is your position at all objective?

 

[Rockdiamond]

Bryan, my position is that judging the cut of a princess cut diamond is subjective- no matter who does it.
AGSL can perform as many scientific tests as you want. Once a person looks at that data, and decides which is better we're into subjective grading.
Who's to say that red in a certain percentage is "better" than green- or white- in ASET?
This photo, from your article, is described as diamonds with deficits in light performance

What's the "deficit" in light performance in the second and fourth stone ( looking left to right)
When you are considering what you term "deficits" are you also considering spread for the price?

 

[Rockdiamond]

I'm not trying to attack AGSL Princess cuts- they have a definite appeal and consistent type of light performance from stone to stone. A lot of people will choose them based on the visual appeal.

Still, I honestly believe that the grade is too narrow. The basic design of a Princess Cut Diamond is versatile.
If a human observation test was done as part of the grade, and people were shown AGSL 0 cut grade stones versus well cut stones outside the current boundaries, I don't believe the top grade would be as narrow.

In my perfect world, AGSL would re-evaluate PC cut grading to be more inclusive.
Say the grade still took the same approach to finish and symmetry but included more PA/CA/Table depth combos.
This will encourage more diversity in truly well cut stones. It would also encourage more cutters to use AGSL
I'd love to see AGSL take a greater market share- it's a great organization.

 

[AdaBeta27]

http://www.whiteflash.com/loose-diamonds/princess-cut-loose-diamond-2959567.htm
Might be out of budget at $5852 wire. Nice smaller table, not an excessive depth.

Inclusion is a feather but I can't see it anywhere on the inclusion plot. You'd have to ask.
Whiteflash ACA
AGS 000 princess
1.057 ct
G VS2
Depth % 73.9
Table % 66.4
Crown Angle 35.9
Star 0.0
Pavilion Angle 40.4
Crown % 11.0
Lower Girdle % 0.0
Measurements 5.67x5.57x4.11

ASET / Idealscope / photos are helpful. But princess is a "fancy" and there are a lot of variations in how to cut one. One thing that all the "fancy" cuts have in common is they almost have to be seen in order to make a decision. H&A RB is a lot more homogenous and predictable. They've refined and improved the cutting science of making a princess over the years.
[URL='https://www.pricescope.com/community/threads/do-princess-cuts-get-a-cut-grade-from-gia.71981/']https://www.pricescope.com/community/threads/do-princess-cuts-get-a-cut-grade-from-gia.71981/[/URL]
https://www.pricescope.com/wiki/diamonds/princess-cut-diamond

 

[Texas Leaguer]

Bryan, my position is that judging the cut of a princess cut diamond is subjective- no matter who does it.
AGSL can perform as many scientific tests as you want. Once a person looks at that data, and decides which is better we're into subjective grading.
Who's to say that red in a certain percentage is "better" than green- or white- in ASET?
This photo, from your article, is described as diamonds with deficits in light performance

What's the "deficit" in light performance in the second and fourth stone ( looking left to right)
When you are considering what you term "deficits" are you also considering spread for the price?

I don't have the grading data on the ASET samples readily available. The point was to illustrate different ASET signatures of diamonds that received LP deductions. My guess is the second stone got a deduction for brightness and the fourth stone for leakage or contrast. It is also possible that one or more of the samples got dinged on dispersion. Most commercial princess cuts are deficient in this aspect. I would not consider these to be poorly cut princess necessarily - just that they miss the top grade of AGS 0 because of one or more LP deficits.

Spread is factored into the AGS grading system. Price is obviously not. The system is designed to help a consumer understand the diamond - not to determine if it's a good deal.

Regarding your statement about subjective grading, by this logic there is no possibility of any grading system ever being totally objective. So what is the point? We should not grade diamonds?

 

[Rockdiamond]

Bryan -color and clarity grading are far more objective- although there's still a bit of subjectivity.
Color is basically a linear scale so very little subjective judgement comes into play. An E has more color than a D. If a person can see color they'll see this the same way. Is it a d or an e? A bit of subjectivity involved. This aspect will not change based on different viewing conditions- unless there's not sufficient light to observe color.

Clarity grading is a great example of objective grading. A diamond is graded based on the presence of imperfections. Not their visibility. That's why you'll find such great variations in SI clarity diamonds.
If the crystal is tucked away in a corner, you can't see it with the naked eye. Same booger moved to the middle of the table and it's easy to see. Yet both get the same grade. Is it an SI1 or an SI2? A bit of subjectivity there.
In the case of cut grading there's far more subjective judgement. Brilliance is nothing like color or clarity in how people perceive it. Different eyes see different things as brilliant.

Dispersion is another aspect which won't be seen the same way by different observers. Also brilliance and dispersion are greatly affected by the light under which we observe the diamond. AGSL surely took care in the lighting scenarios used for judging light performance - but the environment they picked is not necessarily similar to the light people are exposed to when viewing their diamonds. These are a few of the reasons brilliance and scintillation perceptions are far more subjective than color and clarity. Also great reasons a wider grade would make a lot of sense.

The ASET pic is illustrative in that you're basically saying the images are not useful in determining light performance "defects"

After all this time and discussion I have indeed become far more familiar with ASET signatures. Exclusion of diamonds like stone number two in particular is a great example of the problems with the AGSL princess cut grade.
Its very likely that stone has the type of light performance that many observers would pick over an AGSL 0.

 

[Texas Leaguer]

Bryan -color and clarity grading are far more objective- although there's still a bit of subjectivity.
Color is basically a linear scale so very little subjective judgement comes into play. An E has more color than a D. If a person can see color they'll see this the same way. Is it a d or an e? A bit of subjectivity involved. This aspect will not change based on different viewing conditions- unless there's not sufficient light to observe color.

Clarity grading is a great example of objective grading. A diamond is graded based on the presence of imperfections. Not their visibility. That's why you'll find such great variations in SI clarity diamonds.
If the crystal is tucked away in a corner, you can't see it with the naked eye. Same booger moved to the middle of the table and it's easy to see. Yet both get the same grade. Is it an SI1 or an SI2? A bit of subjectivity there.
In the case of cut grading there's far more subjective judgement. Brilliance is nothing like color or clarity in how people perceive it. Different eyes see different things as brilliant.

Dispersion is another aspect which won't be seen the same way by different observers. Also brilliance and dispersion are greatly affected by the light under which we observe the diamond. AGSL surely took care in the lighting scenarios used for judging light performance - but the environment they picked is not necessarily similar to the light people are exposed to when viewing their diamonds. These are a few of the reasons brilliance and scintillation perceptions are far more subjective than color and clarity. Also great reasons a wider grade would make a lot of sense.

The ASET pic is illustrative in that you're basically saying the images are not useful in determining light performance "defects"

After all this time and discussion I have indeed become far more familiar with ASET signatures. Exclusion of diamonds like stone number two in particular is a great example of the problems with the AGSL princess cut grade.
Its very likely that stone has the type of light performance that many observers would pick over an AGSL 0.

David,
I struggle to find much of anything in this long post to agree with. Except maybe the fact that you make my point, albeit unintentionally, that even the GIA system (which the whole diamond world relies upon to a very large extent) involves multiple elements of subjectivity. Human graders are doing both color and clarity grading. Do you think that does not introduce subjectivity? How many rechecks and disputes do you think happen on a daily basis between dealers and the color/clarity grades they receive at the labs ?

The AGSL light performance cut grading system is far more objective in that it is based upon mathematical models of light behavior, which follow the laws of physics.

So before you make your blanket criticisms of AGSL by continually crying "subjective!", try to keep these things in mind.

 

[Rockdiamond]

Bryan, any quantification of "light performance" itself is ONLY opinion. And it's based on suppositions that are necessarily arbitrary. Some decisions had to be made in order to standardize the tests- but that means the results are not consistent in real life based on a number of factors.
How large is the person's head looking at the diamond? Where is the light coming from, what's the color and intensity of the light? These two considerations have great bearing on light performance measurement.
Color and clarity grading are physical aspects unaffected by head size, or where the light is coming from.
I'm sure many stones come in for re-checks- and I'm also sure that in the vast majority of cases GIA does NOT change the grading.

So before you claim a stone is better for "scientific" reasons, remember that the judgment of light performance measurement is NOT science. You can't even tell us why you claim a stone who's ASET is pictured is "deficient"- yet you dd not hesitate to knock the stone.

Sell AGSL 0 cut grade princess cuts based on your belief that they look nicer- that's entirely fair.
But getting people to pay more for a diamond for reasons that are based on these subjective opinions described as "scientific" is misleading.

 

[Texas Leaguer]

Bryan, any quantification of "light performance" itself is ONLY opinion. And it's based on suppositions that are necessarily arbitrary. Some decisions had to be made in order to standardize the tests- but that means the results are not consistent in real life based on a number of factors.
How large is the person's head looking at the diamond? Where is the light coming from, what's the color and intensity of the light? These two considerations have great bearing on light performance measurement.
Color and clarity grading are physical aspects unaffected by head size, or where the light is coming from.
I'm sure many stones come in for re-checks- and I'm also sure that in the vast majority of cases GIA does NOT change the grading.

So before you claim a stone is better for "scientific" reasons, remember that the judgment of light performance measurement is NOT science. You can't even tell us why you claim a stone who's ASET is pictured is "deficient"- yet you dd not hesitate to knock the stone.

Sell AGSL 0 cut grade princess cuts based on your belief that they look nicer- that's entirely fair.
But getting people to pay more for a diamond for reasons that are based on these subjective opinions described as "scientific" is misleading.

It would follow from your logic that we should all just sell diamonds on our 'belief that they look nicer' and that everyone should stop selling diamonds based upon laboratory reports because judgments were made when creating the system and "arbitrary" grades were assigned to rate different aspects of quality. And the fact that merchants would charge more for a Triple Ex than for a VG would be somehow "misleading".

David, your arguments don't stand up to even casual scrutiny.

 

[Rockdiamond]

I am very open to any sort of scrutiny you'd care to apply- but instead you're not answering my questions.
You can't or won't respond to my points about the arbitrary decisions made about head size and light placement?
Or why you claim a stone has deficits.


And yes, I do feel that sellers who discourage buyers from J color- or SI stones using methods like "Oh no one likes J colors" or "all SI stones are problematic" are misleading consumers.
I do feel that sellers who automatically suggest skipping GIA VG cut grades are upselling.
Yes, many EX stones cost more- and many may indeed be worth more to a given buyer- but by no means all.

One of the main purposes of an open forum like this is consumer education. Using the term "scientific" on subjective grades is misleading.
I have never used that term to describe GIA's method of grading.

 

[Texas Leaguer]

I am very open to any sort of scrutiny you'd care to apply- but instead you're not answering my questions.
You can't or won't respond to my points about the arbitrary decisions made about head size and light placement?
Or why you claim a stone has deficits.


And yes, I do feel that sellers who discourage buyers from J color- or SI stones using methods like "Oh no one likes J colors" or "all SI stones are problematic" are misleading consumers.
I do feel that sellers who automatically suggest skipping GIA VG cut grades are upselling.
Yes, many EX stones cost more- and many may indeed be worth more to a given buyer- but by no means all.

One of the main purposes of an open forum like this is consumer education. Using the term "scientific" on subjective grades is misleading.
I have never used that term to describe GIA's method of grading.

In the AGS system head shadow is most definitely accounted for. Blue in ASET is specific to illustrating the effects of obscuration. In terms of 'light placement' the system ray traces 40,000 light rays entering the diamond from the 3 dimensional space above the horizon. While it is possible for light to enter a diamond below the horizon, most of the light that is returned to the eye normally enters the diamond from above.



Regarding the specific deductions of the samples alluded to, I was able to pull up the grading data on stone # 2. It had a GIA report and was marketed as a 'signature ideal' that was sent to AGSL for light performance testing. Ironically, though it is being represented as an ideal cut, it does not even get the top grade from GIA for symmetry. That is what I would say is a bit misleading.

 

[Rockdiamond]

Nice way to skirt the actual question Bryan.
I know AGSL used a model for head size to account for obstruction.
My question is, how does AGSL determine what size head to use? People do have different size heads, and this will have a noticeable impact on the measurements.
You mention 40,000 light rays- how many rays hit hit a diamond in real life?
If there are more or less won't that change the LP?
Or if the lighting sources are not arranged like the stick figure lighting sources in your answer- and most of the time light sources don't follow such a simple model.
What about reflected light?
The idea behind the AGSL Princess Cut grade is a good one- the implementation is weak. The market is bearing this out.


In terms of the stone you claim has deficits: It seems that in terms of light performance, someone at your company agreed with me.
I know that many princess cuts I've tested with similar ASET signatures to your #2 can look kickin' in real life.
Based on this- isn't it shortsighted to advise consumers that red is better than green?
There's charts published that make that claim.

With regards to EX versus VG symmetry.
GIA will indeed grant a round diamond with VG symmetry an EX cut grade in some cases. The reason is that the difference between X and VG symmetry grade is so slight that it is not possible to see with the naked eye- meaning that such a difference can NOT impact Light Performance.
I agree AGSL would ding it for that aspect- but that again shows why widening the parameters will produce a far more workable cut grade.