Diamond Expert Advice Needed ASAP

[nkc]

I would appreciate it if you could let me know which diamond of the two attached certificates is better and why. Please ignore the color, inclusion type and location detail. I'm only interestes in the light performace, symmetry and visual qualities of the diamond. Your help is highly appreciated.

 

[JulieN]

The -0005 is better. You can see in the photo that the -0034 i significantly darker looking due to its shallow proportions.

 

[yssie]

https://myapps.gia.edu/ReportCheckPortal/getReportData.do?&reportno=1139464687&weight=1.50
https://myapps.gia.edu/ReportCheckPortal/getReportData.do?&reportno=2145798741&weight=1.51

Ditto. Would go w/ the 35/40.8 - w/ the other shallower one numbers on the reports + GIA rounds pav up make the 35/40.8 the safer blind option..

 

[nkc]

Thank you JulieN and Yssie.

Could you please educate me on why the shallower one shows slightly better optical brilliance in the report? Also, shall I ignore the HCA score? The first scores 1.6 while the second (shallower) scores 0.6.

Thank you for your reply.

 

[JulieN]

HCA scores of under 1 are on the shallow side and sometimes make better earring/pendant stones where they will not be seen up close.

If you scroll down to the proportions section at the bottom of the page, I expect yours to be in between the "shallow" and "very shallow" examples. http://ideal-scope.com/1.using_reference_chart.asp

You can read this for an explanation http://goodoldgold.com/4Cs/Cut/Proportions/

 

[nkc]

JulieN,

I only see pictures of ideal, shallow, deep, etc. cuts. No dimentions are indicated. Do you think both diamonds are shallow? Why?

I was trying to understand why the shallower diamond indicated better optical brilliance in the certificate but now I'm confused!

 

[JulieN]

the second one is shallow. the first one will be brighter.

 

[nkc]

JulieN,

When is a diamond considered shallow (what dimensions)?

If the first is brighter, why does the second show better optical brilliance results in the report?

 

[JulieN]

The optical brilliance thing only shows leakage. Both stones are not leaky.

Pavilion angle <=40.5 is shallow and needs to be checked. It can work with complimentary crown angles but there is a difference compared to a traditional Tolkowsky.

 

[nkc]

Thank you JulieN

Any other comments about the first diamond? What do you think about the H&A and overall symmetry? Is there anything else that can be better?

 

[John P]

At the given measurements neither diamond is what the trade would consider shallow.
GIA rounds some of the number on grading reports.

So the reported 34.5/40.6 could actually be 34.7/40.7.
And the reported 35.0/40.8 could actually be 34.8/40.7.

There's no way to tell which has meaningfully steeper or shallower proportions.

The given photos are not taken in a way that demonstrates cut precision. I tend to agree that the standard GCAL photo scheme makes the diamond ending in "005" have less obstruction in the published photomicrograph. But that may simply be a function of the proximity of the black camera lens to the diamond's table.

Edited to add: Woops. I went Black Friday numbers-crazy. Revised data above...same message.

 

[Karl_K]

So the reported 34.5/40.6 could actually be 34.7/40.7.

Gcal says 34/40.4 which is shallow.
GIA says 34.5/40.6 badly rounded.
Who knows which is more correct.
Strike one

Looking at the gcal picture it does show more obstruction than other well cut examples.
So that is strike 2.

buying blind
Strike 3

Its out!! :}

 

[nkc]

Thanks John and Karl
I agree with John that both fall within the ideal proportion range. But, I understand that the first (005) is a safer/ better choice.
Any other comments about the first diamond? What do you think about the H&A and overall symmetry? Is there anything else that can be better?

 

[nkc]

John Pollard Diamond Expert Advice Needed ASAP

John Pollard,

I like the diamond ending in 0005 but would like to check if you see anything that could be better. I have been told by GCAL that it's excellent H&A. Is there anything else I should check? Do you see anything that could be an area of concern?

 

[Doc_1]

So the reported 34.5/40.6 could actually be 34.7/40.7.

Gcal says 34/40.4 which is shallow.
GIA says 34.5/40.6 badly rounded.
Who knows which is more correct.
Strike one

Looking at the gcal picture it does show more obstruction than other well cut examples.
So that is strike 2.

buying blind
Strike 3

Its out!! :}

Sorry to interrupt this thread and apologize to the OP but i would like an opinion on a stone i am interested in posted:
[URL='https://www.pricescope.com/community/threads/what-do-you-think-of-this-round-please.182514/']https://www.pricescope.com/community/threads/what-do-you-think-of-this-round-please.182514/[/URL]
Sorry again i wish the forum has the option of PM members.

 

[John P]

Re: John Pollard Diamond Expert Advice Needed ASAP

John Pollard,

I like the diamond ending in 0005 but would like to check if you see anything that could be better. I have been told by GCAL that it's excellent H&A. Is there anything else I should check? Do you see anything that could be an area of concern?

NKC: The numbers are promising. Beyond that, without an ASET or ideal-scope (minimum) I can't comment decisively. The GCAL images are helpful in seeing that it has a nice level of cut-precision. Certainly better than average. As far as the level of "H&A" precision goes, that designation can mean different things. Standards vary quite a bit. Based on experience and observation GCAL's standards are not the loosest, but they are not the strictest. To make a meaningful judgment I'd need to see the diamond.

 

[nkc]

John Pollard,

Thank you for your reply.

I just found this on Blue Nile website. They say that all thier signature diamonds are hearts and arrows (link below):

http://www.bluenile.com/signature-ideal-round-diamonds

I understand that it is difficult to make a decision without seeing the diamond. But with the information we have and if you were buying a diamond, would you consider buying this?

Also, is there any other concerns or anything I should check? The light performance is rated as EX on GCAL, do I need further info on this?

 

[Karl_K]

I just found this on Blue Nile website. They say that all thier signature diamonds are hearts and arrows (link below):

No diamond is h&a unless h&a images are shown to prove it.
That level of proof is needed from any vendor.
Since they do not do so they are not accepted as h&a here.

 

[nkc]

Karl,

I beleive their statement is correct unless there's something I don't understand. Why would a big company post a false statement on their website?

 

[diamondseeker2006]

They can define "hearts and arrows" any way they want. Whether or not they use the same standards as other vendors, we have no idea since they do not provide the hearts images (or any images, for that matter).

We see stones on here frequently that have laser inscriptions that say "hearts and arrows". That doesn't mean a thing, either.

 

[nkc]

Who sets the standards?

Any jeweller can say that his standards are the best. How do we know?

 

[nkc]

Thank you guys but my question is addressed to John Pollard.

 

[John P]

I had a long layover in the BA lounge at Heathrow airport today. Apologies in advance for the length of my response. Karl and diamondseeker2006 said, in a nutshell, what I'll elaborate-on.

Karl, I beleive their statement is correct unless there's something I don't understand. Why would a big company post a false statement on their website?

Not false. Just not meaningful. Many sellers advertise diamonds as being “H&A” but the label can mean different things, just as it does when sellers promote diamonds as “ideal” - or a car salesman says something is a “cream-puff.”

RE Ideal: Imagine three companies... Company A is a small seller focused on boutique quality; only promoting diamonds with AGS Ideal light performance as “ideal.” Company B is a volume seller with a big inventory, promoting all AGS 0 and GIA EX diamonds as “ideal” - whether or not they conform to AGS criteria. Company C is a sketchy outfit with reports from labs you’ve never heard of. They slap the “ideal” label on every diamond in the store as a positive buzzword – including diamonds which would make any cut enthusiast cringe.

So when it comes to “ideal” as a descriptor, we can expect the standards, meaningfulness, value - and markups - between those three companies to be different. Even though the descriptor is the same.

Moving to H&A: Let’s say Company A is aware of the original production and grading standards in Japan and the current HRD system of grading H&A. They only promote diamonds conforming to such standards as “H&A.” They also go to the expense of photographing and providing H&A images, demonstrating the level of cut-precision in each diamond (as much as is possible via 2D photo)... Company B, the volume seller, claims their “signature” line is “H&A” but they don’t provide photos or published criteria. Some of those diamonds will show some kind of H&A pattern as a cutting by-product (see RE Mass-Production below) but the most elite H&A diamonds will not be common there; simply because the producers of diamonds with painstaking 3D cut-precision can sell them to cut-focused dealers for more money (like Company A)... Then you have Company C. They have low caliber “toy” viewers in their stores which can make even marginal crowns look symmetrical. Some do what diamondseeker2006 described: They ask GIA to inscribe “Hearts and Arrows” on the grading report, regardless of the actual precision, so that when a consumers sees the words “Hearts and Arrows” on the GIA report they can be convinced that the lab judged the diamond to be H&A, and so it is worth more. Well the lab did nothing of the sort; they just wrote the inscription the dealer asked-for. He could just have easily asked for “D Flawless” to be inscribed on a J-SI2.

RE Mass-Production: With producers cutting millions of carats each year and with tools improving there will logically be round diamonds which show some kind of Hearts & Arrows pattern, even if they were not planned that way. These "happy accidents” finish with enough 2D precision (usually in the crown or "arrows") to be separated out for marketing and sale as Hearts & Arrows diamonds in places with viewers, but not with the precision - or expense or weight sacrifice - of a dedicated top H&A production. You can see examples of the "happy accident" H&As in some of our USA malls. But with no regulation or standards enforced, they vary wildly in consistency.

At least with terms like “ideal” and “excellent” we have meaningful lab grading to serve as some sort of reference. Currently no major USA lab makes an assessment of H&A (this will eventually change). The result is that any seller can claim that any diamond is a “H&A” diamond with no need to enforce meaningful standards. On my home computer I have many, many photos of diamonds sold as being "Hearts & Arrows" which clearly don't have what I consider a necessary level of cut-precision, by any critical definition.

Until a major USA laboratory begins grading 2D H&A patterns (the first stepping stone) and eventually steps up to to grading 3D cut precision (which goes beyond "H&A" patterning) the purchase of generic H&A diamonds in the USA is a buyer-beware proposition. It is also important to note that diamonds can be cut with precision but fail to have been crafted with the critical angles required for optimal light performance: The two are exclusive of each-other, and no current USA grading system accounts for both elements.

The bottom line: Without some kind of evidence (2D photos at a minimum, a recognized and controlled 3D cut precision standard as a maximum) there simply isn’t any way to communicate what level of cut precision or H&A any given diamond has. That’s what drives the replies you’ve received so far.

Who sets the standards? Any jeweller can say that his standards are the best. How do we know

Bingo. And I believe it serves some further food for thought... If - by definition - 90% of all round brilliant diamonds are in the bottom 90% of total cut-quality, how can 100% of sellers claim to have “the best” ?

 

[nkc]

I had a long layover in the BA lounge at Heathrow airport today. Apologies in advance for the length of my response. Karl and diamondseeker2006 said, in a nutshell, what I'll elaborate-on.

Karl, I beleive their statement is correct unless there's something I don't understand. Why would a big company post a false statement on their website?

Not false. Just not meaningful. Many sellers advertise diamonds as being “H&A” but the label can mean different things, just as it does when sellers promote diamonds as “ideal” - or a car salesman says something is a “cream-puff.”

RE Ideal: Imagine three companies... Company A is a small seller focused on boutique quality; only promoting diamonds with AGS Ideal light performance as “ideal.” Company B is a volume seller with a big inventory, promoting all AGS 0 and GIA EX diamonds as “ideal” - whether or not they conform to AGS criteria. Company C is a sketchy outfit with reports from labs you’ve never heard of. They slap the “ideal” label on every diamond in the store as a positive buzzword – including diamonds which would make any cut enthusiast cringe.

So when it comes to “ideal” as a descriptor, we can expect the standards, meaningfulness, value - and markups - between those three companies to be different. Even though the descriptor is the same.

Moving to H&A: Let’s say Company A is aware of the original production and grading standards in Japan and the current HRD system of grading H&A. They only promote diamonds conforming to such standards as “H&A.” They also go to the expense of photographing and providing H&A images, demonstrating the level of cut-precision in each diamond (as much as is possible via 2D photo)... Company B, the volume seller, claims their “signature” line is “H&A” but they don’t provide photos or published criteria. Some of those diamonds will show some kind of H&A pattern as a cutting by-product (see RE Mass-Production below) but the most elite H&A diamonds will not be common there; simply because the producers of diamonds with painstaking 3D cut-precision can sell them to cut-focused dealers for more money (like Company A)... Then you have Company C. They have low caliber “toy” viewers in their stores which can make even marginal crowns look symmetrical. Some do what diamondseeker2006 described: They ask GIA to inscribe “Hearts and Arrows” on the grading report, regardless of the actual precision, so that when a consumers sees the words “Hearts and Arrows” on the GIA report they can be convinced that the lab judged the diamond to be H&A, and so it is worth more. Well the lab did nothing of the sort; they just wrote the inscription the dealer asked-for. He could just have easily asked for “D Flawless” to be inscribed on a J-SI2.

RE Mass-Production: With producers cutting millions of carats each year and with tools improving there will logically be round diamonds which show some kind of Hearts & Arrows pattern, even if they were not planned that way. These "happy accidents” finish with enough 2D precision (usually in the crown or "arrows") to be separated out for marketing and sale as Hearts & Arrows diamonds in places with viewers, but not with the precision - or expense or weight sacrifice - of a dedicated top H&A production. You can see examples of the "happy accident" H&As in some of our USA malls. But with no regulation or standards enforced, they vary wildly in consistency.

At least with terms like “ideal” and “excellent” we have meaningful lab grading to serve as some sort of reference. Currently no major USA lab makes an assessment of H&A (this will eventually change). The result is that any seller can claim that any diamond is a “H&A” diamond with no need to enforce meaningful standards. On my home computer I have many, many photos of diamonds sold as being "Hearts & Arrows" which clearly don't have what I consider a necessary level of cut-precision, by any critical definition.

Until a major USA laboratory begins grading 2D H&A patterns (the first stepping stone) and eventually steps up to to grading 3D cut precision (which goes beyond "H&A" patterning) the purchase of generic H&A diamonds in the USA is a buyer-beware proposition. It is also important to note that diamonds can be cut with precision but fail to have been crafted with the critical angles required for optimal light performance: The two are exclusive of each-other, and no current USA grading system accounts for both elements.

The bottom line: Without some kind of evidence (2D photos at a minimum, a recognized and controlled 3D cut precision standard as a maximum) there simply isn’t any way to communicate what level of cut precision or H&A any given diamond has. That’s what drives the replies you’ve received so far.

Who sets the standards? Any jeweller can say that his standards are the best. How do we know

Bingo. And I believe it serves some further food for thought... If - by definition - 90% of all round brilliant diamonds are in the bottom 90% of total cut-quality, how can 100% of sellers claim to have “the best” ?

John Pollard,
Thank you for your reply. I have some questions and comments but cannot spent much time here this week. I will be back next week with some questions. In the meanwhile, I would appreciate it if you could post a picture of what you think is perfect hearts & arrows and another picture of a diamond claimed to be H&A.
denverappraiser provided some good information in his reply to a question I posted on another thread. It seems that there isn't set standards regarding H&A. Each grader may have a different definition.
I also think if a seller does not provide pictures it does not mean their diamonds are not H&A especially if they have a great return policy. Also, how do we know that those who provide pictures are actually providing pictures for the same diamond you're buying?
Most important, how do we know whose standards and definitions are most accurate?