Cut grade deduction due to brillianteering

[just_browsing]

I finally got my SARIN and light trace reports back for my 1.35ct IF H diamond, and the thing that jumped out at me was the estimated GIA cut grade of FAIR. The actual GIA report graded the cut as EXCELLENT. I know the GIA excellent range is already pretty wide, but could this diamond have been significantly overgraded even by GIA's own standards?
http://www.gia.edu/cs/Satellite?pag...&c=Page&cid=1355954554547&reportno=7201537694

The fine print in the SARIN report notes "Cut grade deduction due to brillianteering." I've read the past articles on painting and digging, and the girdle profile on the report does seem to indicate some brillianteering issues. However, the light trace image looks great and I do not notice any girdle issues from the video, so maybe it should not be a huge concern. I've been skeptical of this diamond because it seems to be a great value ($7850) for its specs.

It would seem odd to utilize painting or digging on a diamond of this size. Could the girdle profile simply indicate a diamond that was not precisely cut even though it received a GIA Triple Ex? Also I would only expect a difference in one cut grade and not a deduction from excellent to fair.

 

[just_browsing]

Any thoughts about painting or digging on this diamond before I make my final decision? Both gemologists I've talked to did not see any issues with brillianteering and the GIA report grades this an excellent cut, but I wanted to make sure to get one more opinion from the experts here on Pricescope.

I think the light trace image looks really good, but understand that it is computer generated.

Thanks!

 

[denverappraiser]

Sarin is a tool for measuring all of those various angles and such. Sarin doesn't assign a grade and it doesn't assign deductions. That's coming from the dealer (or their supplier). Talk to them about it. Brillianteering is something will ding for, and they apparently didn't do it in this case, so we're seeing a difference between how your grader uses his/her Sarin and GIA uses theirs.

 

[kenny]

Any thoughts about painting or digging on this diamond before I make my final decision?

I'm no cut expert or pro, but I am a consumer with some diamond experience.
If I were to plan to keep this diamond forever I'd not care that it had painting and digging.
In fact I once saw an Eightstar diamond cut, which I believe is heavily brillianteered, and I'd LOVE to own one!

Dinging it seems to be an industry hang up that I suspect is related to a perception of cheating while cutting.
IMO it's just smart cutting and all that matters is how it looks.

BUT

If I thought I ever might want to sell it or upgrade it then I would not buy it.
Good, bad, right, or wrong, the market is the market.
Even if it's stupid that it is getting dinged, it is getting dinged ... and that may matter to buyers who are poorly informed, insecure and fearful of what they don't understand, aka the majority.
Hence it may take longer to sell and sell for a lower price ... much like a diamond with fluorescence.
Unfair, but it is what it is.

How do you know if it'll be a keeper or a stepping stone?
(Stepping stone ... Hahah, I should trademark that!)
Your first stone is more-likely to be a stepping stone, especially since you've found PS.
If this is your third upgrade over a 15 year period then you are experienced and the stone is more likely to be a keeper.

 

[just_browsing]

Thanks for your responses. I've sat down in the store with this stone for a long long time and compared it to an AGS 1 cut diamond and it looked beautiful. I'm hoping that this is that forever stone and the price is right!

To clarify, the GIA report actually shows an excellent cut grade, so I was just wondering if GIA could have grossly overgraded this stone based on their criteria.

 

[Rhino]

Sarin is a tool for measuring all of those various angles and such. Sarin doesn't assign a grade and it doesn't assign deductions. That's coming from the dealer (or their supplier). Talk to them about it. Brillianteering is something will ding for, and they apparently didn't do it in this case, so we're seeing a difference between how your grader uses his/her Sarin and GIA uses theirs.

Hey bossman. While its true the Sarin doesn't assign a "hard grade" it's estimations are 99% and it does assign deductions for brillianteering (painting and digging).

Peace,
Jon

 

[denverappraiser]

We’re apparently talking about that 1%

In any case, the point of my post was that it’s not Sarin who’s doing it. It’s a piece of software that’s estimating using data derived from a Sarin scanner. These are not all the same and they don’t all use the same rules. Even the various versions sold by Sarin, and they’re numerous, aren’t all using the same rules. The dealer is who supplied it, and that puts them in the hot seat for what it does or doesn't mean.

We have 3 possibilities here:
1) An error by GIA, the software, or both.
2) A calibration discrepancy between the dealer’s equipment and GIA’s (GIA uses Sarin equipment), or a scanning error during one or both scans.
3) A difference in the algorithm used on the dealer’s computer vs. GIA’s.

 

[Texas Leaguer]

We’re apparently talking about that 1%

In any case, the point of my post was that it’s not Sarin who’s doing it. It’s a piece of software that’s estimating using data derived from a Sarin scanner. These are not all the same and they don’t all use the same rules. Even the various versions sold by Sarin, and they’re numerous, aren’t all using the same rules. The dealer is who supplied it, and that puts them in the hot seat for what it does or doesn't mean.

We have 3 possibilities here:
1) An error by GIA, the software, or both.
2) A calibration discrepancy between the dealer’s equipment and GIA’s (GIA uses Sarin equipment), or a scanning error during one or both scans.
3) A difference in the algorithm used on the dealer’s computer vs. GIA’s.

I would guess #2 is the likely culprit. The official measurement and final authority is the one done by GIA. And as OP says, the ASET light map does not show evidence. So the painting and/or digging out is probably very minor and did not pass the threshhold of the GIA penalty.
It is possible that GIA have changed their algorithm to treat this issue more rationally. As Kenny says, certain brillianteering techniques are not meant to swindle, but rather to improve optics. Those that produce a brighter stone without causing other issues should not be penalized in my opinion. If changes have been made at GIA and the software on the local machine has not been updated, it is possible that #3 is at play.

 

[sharonyanddave]

It is possible that GIA have changed their algorithm to treat this issue more rationally.

Do you have any evidence GIAL has changed its cut grading at all concerning painting and digging or the way it measures girdles measurements in recent years?

Do you have any evidence GIAL has stated in any way their current cut grading is not rational with respect to painting and digging and a change is even necessary?

I suspect the answer to both of these is No and your contrary opinion to GIA and GIAL is framed in an unrealistic supposition.

 

[Texas Leaguer]

It is possible that GIA have changed their algorithm to treat this issue more rationally.

Do you have any evidence GIAL has changed its cut grading at all concerning painting and digging or the way it measures girdles measurements in recent years?

Do you have any evidence GIAL has stated in any way their current cut grading is not rational with respect to painting and digging and a change is even necessary?

I suspect the answer to both of these is No and your contrary opinion to GIA and GIAL is framed in an unrealistic supposition.

I am not aware of any change in GIA grading in this respect. My statement that it is possible that they have tweaked the algorithm is pure speculation. That their penalty system for this issue is too much of a "one size fits all" approach is my personal opinion based upon seeing some of the most carefully crafted, brightest, precision cut diamonds in the world get dinged to VG by their system.
The purpose behind the penalty is to keep from rewarding cutters for using tricks to retain unnecessary weight or to make symmetry faults at the girdle less noticeable. But non-standard indexing can also be used to fine tune and maximize brightness without any other purpose or collateral affects. You may or may not like the flavor such stones (like Eightstar), that's a taste thing which GIA has gone to great lengths to preserve, but to penalize for it from a cut quality perspective is simply not rational. Especially in light of a very broad EX category that rewards cutters for overly steep and deep proportions that retain unnecessary weight and result in loss of performance.

 

[John P]

If I were to plan to keep this diamond forever I'd not care that it had painting and digging.

Kenny, with respect, this is like saying "If I planned to keep this diamond forever I'd not care that it has inclusions." ...Meaning, the scope of "brillianteering" variance includes a massive range with results from benign to malevolent. In much the same way as "inclusions" can run from benign pinpoints to malevolent cavities/chips.

In fact I once saw an Eightstar diamond cut, which I believe is heavily brillianteered, and I'd LOVE to own one!

NOW you're being more specific. Eightstar's brillianteering choice was limited to crown-only painting - two-clicks on the polishing tang, - generally equaling an indexing variation of 7-8 degrees. It brought the upper-halves closer in angle to each other so dispersive fans were less broken up: Resulting in bigger, more frequent fire seen in low light along the girdle.

1. See the leftmost column in the graphic below, Crown-Only > Painting > 1A > 7 and 8°. That's rather benign; although the 2006 GIA system penalizes any diamond painted or dug to that degree, in order to catch more deleterious 'swindling.'

2. Now look at > Digging > 1B, just to the right of 1A. You can see where digging on the crown with two clicks is entirely different, as it creates a dangerous knife-edge girdle and much less intense light return.

Edited to add - Pricescope picture shrinkage alert! Click to see the graphic at full size.
https://www.pricescope.com/files/images/journal/Visible_Effects/image006.gif

Original article:
https://www.pricescope.com/journal/visible_effects_painting_digging_superideal_diamonds

 

[just_browsing]

Thank you for all the detailed responses. While I'm inclined to trust the GIA report cut grade, I've been somewhat skeptical of this diamond because it seems like a very good value for a well cut 1.35ct H IF diamond ($7851). The estimated fair cut grade I received from Ritani only served to reinforce that skepticism. However, I assume Ritani is a lot more likely to have an incorrectly calibrated machine than GIA. To my untrained eye, the diamond looks excellent in person, but I'm planning on taking the diamond to a local appraiser/gemologist for a second opinion.

I've read the GIA literature on painting and digging, and I can't see any evidence of it in the face up view of the diamond. However, the video of the diamond does seem to show some unevenness in the girdle width at the junctions. Unfortunately, I was only able to get a light trace image and not an actual ASET of the diamond to verify.

At the end of the day, if the diamond looks good in person and checks out with the gemologist, I'm inclined to keep it regardless of painting or digging, especially since I'm hoping to keep this one forever. I'll report back after I meet with the gemologist.

Here's an actual image of the diamond:


The video can be found here:
https://www.ritani.com/diamonds/round-diamond-1-35-Carat-H-color-GIA-certified/D-WS10H9

 

[Texas Leaguer]

Thank you for all the detailed responses. While I'm inclined to trust the GIA report cut grade, I've been somewhat skeptical of this diamond because it seems like a very good value for a well cut 1.35ct H IF diamond ($7851). The estimated fair cut grade I received from Ritani only served to reinforce that skepticism. However, I assume Ritani is a lot more likely to have an incorrectly calibrated machine than GIA. To my untrained eye, the diamond looks excellent in person, but I'm planning on taking the diamond to a local appraiser/gemologist for a second opinion.

I've read the GIA literature on painting and digging, and I can't see any evidence of it in the face up view of the diamond. However, the video of the diamond does seem to show some unevenness in the girdle width at the junctions. Unfortunately, I was only able to get a light trace image and not an actual ASET of the diamond to verify.

At the end of the day, if the diamond looks good in person and checks out with the gemologist, I'm inclined to keep it regardless of painting or digging, especially since I'm hoping to keep this one forever. I'll report back after I meet with the gemologist.

Here's an actual image of the diamond:


The video can be found here:
https://www.ritani.com/diamonds/round-diamond-1-35-Carat-H-color-GIA-certified/D-WS10H9

I would be definitely be inclined to trust the GIA report on this issue. Specifically because their painting and digging penalty is strict. I think you would have a much harder decision if GIA dinged the stone to VG. Then you would have to decide to keep the stone because you like it despite the cut pedigree not being the best. As it is, if you like the stone and your expert does not find anything amiss, there would be no reason in my mind not to go forward.

 

[just_browsing]

I met with one gemologist and several sales people and the general consensus was this was an excellent cut stone and they would not be able to find me a better stone for the price. The one concern the gemologist had was that the color looked like it was on the lower end of the H range. He did not see any issues with the cut of the diamond. However, he was pushing hard to try to sell me one of his diamonds. In the end, he was still not able to match the price I got on this stone even if we went down to a VS2 clarity (which was the clarity range I was originally considering). He even tried to sell me into the I color range since he considered this stone to be closer to an I, but I would have been able to get a much better price for an I color diamond online. So I think the lesson here is to be prepared with as much knowledge as possible when you walk into a retail store, and I have to thank all the posters on this site for everything I have learned during my search. Now I think it's time to find that perfect setting!

Thank you!