Diamond experts, please advise on Hearts & Arrows and ASET Image?

[thesearchbegins]

Hi Pricescope friends,

I have been researching diamond cut quality, hearts & arrows quality and ASET evaluations, but still consider myself quite a novice overall. Would anyone be willing to take a look at these images and help advise on whether you consider these good results? Do you think this diamond has strong light performance?
This is for a diamond I'm evaluating for an engagement ring. I've been doing research online and this looks okay and acceptable to my eyes, but again would value the perspective from the diamond experts who are more seasoned with using ASET scopes. Any insight from the community on here would be greatly appreciated. Thank you all in advance!

 

[Karl_K]

grading report?
Or if you dont want to spend time on it just keep looking.
Hearts image and the aset image are both a fail. The grading report will help tell why it failed.

 

[Karl_K]

Thank you for the fast response @Karl_K! Is the grading report basically the GIA report?

yes

 

[Karl_K]

Also @Karl_K I was wondering if you would consider these images a terrible performance = major fail or average light performance or slightly below average? Curious what degree of bad they are...

I tend to treat aset and h&a images as pass or fail not 85/100. This one the fail goes beyond its just not a top end stone into it has issues.
The grading report might or might provide some insight into why.

 

[thesearchbegins]

@Karl_K I was wondering if you would consider these images a terrible performance = major fail or average light performance or slightly below average? Curious what degree of bad they are...

here are the proportions - is this helpful?

PROPORTIONS​

Depth	62.4%
Table	56%
Crown Angle	35.0°
Crown Height	15.5%
Pavilion Angle	40.8°
Pavilion Depth	43.0%
Star Length	55%
Lower Half	75%
Girdle	Medium to Slightly Thick, Faceted, 4.0%

 

[Karl_K]

@Karl_K I was wondering if you would consider these images a terrible performance = major fail or average light performance or slightly below average? Curious what degree of bad they are...

here are the proportions - is this helpful?

PROPORTIONS​

Depth	62.4%
Table	56%
Crown Angle	35.0°
Crown Height	15.5%
Pavilion Angle	40.8°
Pavilion Depth	43.0%
Star Length	55%
Lower Half	75%
Girdle	Medium to Slightly Thick, Faceted, 4.0%

ok numbers after gia grossly rounds them but its not a good indication of what the angles actually are on the diamond and its just plain messed up.
So the numbers where not helpful other than pointing the finger at the cutter and confirming gia rounding stinks. Anyway time to move on.

 

[thesearchbegins]

oh no! what are you referring to as messed up? Are you saying the proportions may not be honest or that the diamond is terribly cut?

 

[thesearchbegins]

Also, would it make a difference if these ASET images were generated images from diamcalc or from a 3d scan and not images I took myself? (perhaps not, just wanted to check). These are the images that the diamond vendor sent me when I asked for them

 

[Karl_K]

It is not well cut.
Im aware they are generated images from scans.
Real images would probably look as bad.
scan based images tend to understate these kinds of issues.

 

[mrsctobe]

Unpopular opinion but I have a diamond that's cut similarly and it sparkles like mad similar to one that's cut perfectly. Do you really need one where mainly experts can tell the difference, is up to you.

 

[thesearchbegins]

thank you for your honest feedback both @mrsctobe and @Karl_K - I really appreciate it.

@mrsctobe do you have any videos or photos of your diamond ring you would be willing to share? no worries if not, just curious to see how it sparkles!

 

[Diamond_Enthusiast]

Sorry but I also don't think this is a well cut diamond.

Why focus on a stone that isn't well cut when there are other better diamonds to consider?

 

[Karl_K]

Unpopular opinion but I have a diamond that's cut similarly and it sparkles like mad similar to one that's cut perfectly. Do you really need one where mainly experts can tell the difference, is up to you.

This one has some digging issues on the upper girdle facets that are going to be eye visible in some lighting.
Its not just a matter of less good images.

 

[TXwidow]

the very knowledgeable folks here will be happy to provide some wonderful options for you if you provide: budget (for stone?/including setting?) - color limitations - clarity limitations - size desired - presuming a round/brilliant stone.

 

[Ibrakeforpossums]

This one has some digging issues on the upper girdle facets that are going to be eye visible in some lighting.
Its not just a matter of less good images.

Karl, where on those images do you see digging? I'm having the worst time understanding that technique. I've read some articles, it just bounces off.
I sucked at algebra, too.

 

[Karl_K]

Karl, where on those images do you see digging? I'm having the worst time understanding that technique. I've read some articles, it just bounces off.
I sucked at algebra, too.

I am not allowed to draw on a vendors image but the green areas around the edge are the biggest sign but there are others like the variation in the white area at the tip of the stars and the end of the uppers. A small amount or some painting is not as bad but in this case it dips into the looks small in some lighting category.

 

[Ibrakeforpossums]

Thank you. I'll study the images.

 

[Diamond_Enthusiast]

green areas around the edge are the biggest sign

@Ibrakeforpossums have a look at the table of ASET images in the link below (focus on the digging columns) and you'll notice similar green patches on the edge like what appears on the ASET the OP posted.

Visible Effects of Painting & Digging on Superideal Diamonds

With grateful acknowledgment to John Pollard, Sergey Sivovolenko, AGSL and GIA Laboratories for valuable resources and input. Graphics produced with DiamCalc software by OctoNus. Note: This article pertains only to […]

www.pricescope.com

This is a key reason why I didn't like the cut of this stone as well.

 

[thesearchbegins]

@Karl_K and everyone in this thread, thank you for sharing your expertise - I'm learning a lot from your pointers. I was wondering what you all think of these 2 other diamonds? For Diamond 2, I only have the hearts and arrows image (no ASET)

Thank you!


Diamond 1





Diamond 2

 

[John Pollard]

Regarding the diamond in the first post - For the purposes of overall context, with T 56 PA 40.8 and CA 35.0 its average proportions are better than approximately 80% of other diamonds with the GIA Excellent grade. It earns HCA Excellent. It's also a candidate for AGS 0 light performance - meaning it falls there on predictive charts - but the indexing deviations (what @Karl_K referred to as digging) could reduce predicted brightness, if it were to be assessed at the lab.

Unpopular opinion but I have a diamond that's cut similarly and it sparkles like mad similar to one that's cut perfectly. Do you really need one where mainly experts can tell the difference, is up to you.

This is good macro context. Candidly, the diamond in the first post is cut with better angles and performance potential than the vast majority you'll find on the market. In that sense, the term "well-cut" means different things - depending on end-goals.

With that said - @thesearchbegins - you seem to be focusing on top performing and precisely cut candidates. If that's the measuring stick, @Karl_K and @Diamond_Enthusiast are providing great feedback.

If you're seeking top optical precision (aka H&A) here's added context - descending examples. I'd just add that in my experience scan/computer-generated-images of hearts & arrows views are not typically as useful as actual images.

Hearts and Arrows Diamonds: Everything You Need To Know

Find out why a Hearts and Arrows diamond is considered to be so special and why they cost more. Discover the benefits here.

www.pricescope.com

 

[John Pollard]

@Ibrakeforpossums - In terms of ASET interpretation, @Diamond_Enthusiast already provided a link to this article on Painting and Digging, which is somewhat advanced but useful in detecting when a cutter might have played games to reduce girdle thickness or chase out inclusions.

I wrote that article forever-ago. In my travels I used to carry a printed version of this chart to correlate with real diamonds in ASET - to teach jewelers how to spot digging. It was designed for Super Ideal makes (PS definition here) but the light draw against the upper halves will be similar across all RB makes.

 

[Karl_K]

@Karl_K and everyone in this thread, thank you for sharing your expertise - I'm learning a lot from your pointers. I was wondering what you all think of these 2 other diamonds? For Diamond 2, I only have the hearts and arrows image (no ASET)

Thank you!


Diamond 1





Diamond 2

post the numbers from the report.
then separate them into 2 posts.

 

[Karl_K]

@Ibrakeforpossums - In terms of ASET interpretation, @Diamond_Enthusiast already provided a link to this article on Painting and Digging, which is somewhat advanced but useful in detecting when a cutter might have played games to reduce girdle thickness or chase out inclusions.

I wrote that article forever-ago. In my travels I used to carry a printed version of this chart to correlate with real diamonds in ASET - to teach jewelers how to spot digging. It was designed for Super Ideal makes (PS definition here) but the light draw against the upper halves will be similar across all RB makes.

What makes it harder in stones like this one there is not the same amount on each set of uppers. That has been the case more often than not other than the ones like wf new line and 8* where they applied uniform painting.

 

[John Pollard]

What makes it harder in stones like this one there is not the same amount on each set of uppers. That has been the case more often than not other than the ones like wf new line and 8* where they applied uniform painting.

Right. Different means to different ends.

The Eightstar and WFNL (RIP) were premeditated painting plans - to achieve specific visual results (whether you like that result or no).

The stone in the OP here was spot-dug - likely to reduce girdle to STK or chase out an aberration. In these cases the main motivation is not visual. But the result is a visual reduction.

 

[Garry H (Cut Nut)]

It is not well cut.
Im aware they are generated images from scans.
Real images would probably look as bad.
scan based images tend to understate these kinds of issues.

Hi Karl and TSB,
Karl I have only read the first bit of this thread, but enough to challenge you.
do you really believe you could identify that diamond and a few others in a line up with whatever most perfectly cut diamonds - naked eye 3 different lighting environments?
As the inventor of many of the tools we use here on Pricescope, I want to point out the purpose of the tools is to find great looking diamonds.
Fail is a very harsh term.
"not perfect H&A's and a little cheating on some minor girdle facets that could lead to a slight loss of contrast in some lighting environments" would be how I would address this diamond

 

[Karl_K]

Hi Karl and TSB,
Karl I have only read the first bit of this thread, but enough to challenge you.
do you really believe you could identify that diamond and a few others in a line up with whatever most perfectly cut diamonds - naked eye 3 different lighting environments?
As the inventor of many of the tools we use here on Pricescope, I want to point out the purpose of the tools is to find great looking diamonds.
Fail is a very harsh term.
"not perfect H&A's and a little cheating on some minor girdle facets that could lead to a slight loss of contrast in some lighting environments" would be how I would address this diamond

In the same way your trick cz set shows one smaller in some lighting(same issue, steep upper girdle facets) this one would do the same to a lesser degree but detectable to the human unaided eye on parts of the diamond in some lighting.
That is a fail.

 

[Garry H (Cut Nut)]

In the same way your trick cz set shows one smaller in some lighting(same issue, steep upper girdle facets) this one would do the same to a lesser degree but detectable to the human unaided eye on parts of the diamond in some lighting.
That is a fail.

Nonsense Karl, and after the diamond is set total absolute nonsense.
firstly if you model the proportions you sill see that the stars are not very close to 55 - probably 52.6% or some dust on the scan.
The crown angle is a touch lower than 35 degrees.
The green has shifted the light entrance - exit angle the same way that the center of a diamond goes red or green by changing from 40.7 to 40.8 degree pavilion angle.
This diamond has the potential to be superb.
The ray is entering the black circled green section.

 

[thesearchbegins]

Thank you for sharing your perspective again @Karl_K and @John Pollard, thank you sincerely as well! Your insight and structured explanation has been incredibly informative as I think through all the pieces that contribute to a super ideal vs high performance/well cut diamond vs poorly cut and more (e.g. ASET image reading, girdle thickness differences, etc). @Garry H (Cut Nut) - wow, thank you for weighing in as well. I've been reading/following your posts for some time and also purchased an idealscope because of you, so it's an honor to get your response. I was curious where you got that ASET image you posted? Is that a projected model of the diamond from the dimensions in the original post?

I was also wondering if you feel the size/carat weight of a diamond makes any difference in influencing cut quality and light performance (or perhaps it doesn't matter as long as the proportions and table size are within ideal range). Are high quality and well cut diamonds harder to find in the larger diamond sizes?

Everyone in here has been so gracious and generous with your feedback, so thank you all greatly!

 

[Garry H (Cut Nut)]

Unpopular opinion but I have a diamond that's cut similarly and it sparkles like mad similar to one that's cut perfectly. Do you really need one where mainly experts can tell the difference, is up to you.

Absolutely. That diamond will outperform more than 95% of GIA XXX diamonds (assuming no transparency issues)

 

[Garry H (Cut Nut)]

This one has some digging issues on the upper girdle facets that are going to be eye visible in some lighting.
Its not just a matter of less good images.

The stone is more likely slightly out of round Karl and the facets are steeper East west.