Which would you buy? Need advice to put me over the edge : )

[lovedogs]

This one looks nice and under budget, but I'm new to this so not quite sure how to judge the cloud inclusions. I'll throw it out here anyway.

https://www.withclarity.com/diamonds/index/diamonddetail/id/6843454386

That one has solid potential. Not sure about the clouds, but hoping they don't affect transparency since it's a VS2 and looks clear in the video. And scores 1.4 on the HCA.

 

[kmajid]

Thanks again for everyone's help! Wondering if any of these should be added to the consideration list. I'm trying to avoid going lower than H, but it seems i may need to have some backup options just in case.

LD12389218
LD11975775
LD11985714

 

[headlight]

All stones mentioned in this thread, with the exception of the one with knot inclusion, are leaky under the table.

How would a buyer know this... How did you know straightaway to be able to weed the bad ones out? Thx!

 

[jp201845]

How would a buyer know this... How did you know straightaway to be able to weed the bad ones out? Thx!

I'm no expert but I'm guessing all the stones in question are from BN, and since there are no advanced images you have to look at the video to determine light leakage....so I'm thinking if some arrows are washed out and not clearly visible there is some kind of light leakage under the table?

 

[flyingpig]

How would a buyer know this... How did you know straightaway to be able to weed the bad ones out? Thx!

I'm no expert but I'm guessing all the stones in question are from BN, and since there are no advanced images you have to look at the video to determine light leakage....so I'm thinking if some arrows are washed out and not clearly visible there is some kind of light leakage under the table?

It takes alot of staring at different videos of different diamonds of all sorts of angles and flaws, and knowing the light structure BN uses. In general, when there is leakage, it appears glassy, windowy, and watery. This is very different from light reflection.
I personally do not like the photographic settings that BN uses. They mask diamonds' flaws rather very well. In addition, diamonds are often tilted.

Take a look at this one. See 2 o'clock under the table. You see black triangles between the arrows and there is glassy apperance. Stuff like this is easy to detect. Some are a bit harder.
https://www.bluenile.com/diamond-details/LD12355234
Under the IS, it would appear like this.
https://www.pricescope.com/communit...ope-need-input-on-this-diamond-please.240443/

PS. Washed out arrows indicate steep crown and deep pavilion, which often cause light leakage, but not always.

 

[headlight]

It takes alot of staring at different videos of different diamonds of all sorts of angles and flaws, and knowing the light structure BN uses. In general, when there is leakage, it appears glassy, windowy, and watery. This is very different from light reflection.
I personally do not like the photographic settings that BN uses. They mask diamonds' flaws rather very well. In addition, diamonds are often tilted.

Take a look at this one. See 2 o'clock under the table. You see black triangles between the arrows and there is glassy apperance. Stuff like this is easy to detect. Some are a bit harder.
https://www.bluenile.com/diamond-details/LD12355234
Under the IS, it would appear like this.
https://www.pricescope.com/communit...ope-need-input-on-this-diamond-please.240443/

PS. Washed out arrows indicate steep crown and deep pavilion, which often cause light leakage, but not always.

So 2 more questions... the input on that thread was that the leakage area wouldn’t be a problem??? Also, what numbers delineate steep crown and deep pavilion? I always see the reference to steep-deep but don’t know what those measurements would be. Thank you!

 

[flyingpig]

So 2 more questions... the input on that thread was that the leakage area wouldn’t be a problem???

As I mentioned, some leakage is easier to detect than others.
https://www.pricescope.com/communit...ope-need-input-on-this-diamond-please.240443/
https://www.jamesallen.com/loose-di...g-color-vs2-clarity-excellent-cut-sku-4798544
The leaky area at 8~9 oclock actually also reflects some amount of light. In this case, the leakage is very hard to detect in both JA video and IRL without backlighting. So, I agree with other members' assessment from that thread that the leakage may not be an issue.
However, https://www.bluenile.com/diamond-details/LD12355234 , this stone has more severe optimal asymmetry than the JA stone does, and light leakage is just too obvious, at least for me.

Also, what numbers delineate steep crown and deep pavilion?

Steep crown and deep pavilion combos always score 2 or great in HCA; Garry really don't like them. Some combos in HCA 2.0~2.4 may be just fine such as 35/41 and 35.5/40.8. But anything steeper and deeper will have light leakage.

 

[headlight]

So a extremely slight difference in the numbers can make suck a difference? My stone is 35 and 40.8 (just off from the example you gave of 35.5 with 40., yet mine gets all excellents for light return, Fire, & scintillation on the HCA. So just that .5 differential would move it over to be considered a steep deep (or at least as far as HCA is concerned)?

 

[jp201845]

So a extremely slight difference in the numbers can make suck a difference? My stone is 35 and 40.8 (just off from the example you gave of 35.5 with 40., yet mine gets all excellents for light return, Fire, & scintillation on the HCA. So just that .5 differential would move it over to be considered a steep deep (or at least as far as HCA is concerned)?

With GIA stupid rounding makes looking at the numbers on the report even more complicated. But nothing wrong with a 35/40.8 combo....

 

[lovedogs]

Thanks again for everyone's help! Wondering if any of these should be added to the consideration list. I'm trying to avoid going lower than H, but it seems i may need to have some backup options just in case.

LD12389218
LD11975775
LD11985714

What do they score on the HCA?

Edit. I never like "clarity grade is based on clouds that aren't shown". Although not sure how much it is an issue for a vs2. I know for SI stones it's a huge red flag.

 

[headlight]

With GIA stupid rounding makes looking at the numbers on the report even more complicated. But nothing wrong with a 35/40.8 combo....

Do you think the GIA Facetware is more accurate? It gives more specific measurements for my stone than does my report (more like an AGS report). If I go by that, the depth on my stone isn’t as bad
But, interesting, Facetware gives my diamond a 62.7 but has 63 on the report, yet I’ve seen other reports on other stones (incl. my sister in law’s with a 62. that state 62.7, etc. and they aren’t rounded on the report. In the case of my sister-in-law’s, her’s is an older report (the blue reports) so I thought maybe GIA wasn’t rounding back then. Yet I’ve seen many stones recently online that didn’t round up to 63 as described above on the newer reports (the brown/gold color). Any insight into this?? (P.S. My sister-in-law’s report is from AFTER they began doing cut grading.)
Furthermore, regarding the rounding, on the Facetware it states 15.8 vs 16 on my report, as well as 42.9 vs 43. So would these non-rounded numbers be the actual measurements? If so, why would GIA “take the time” to round when they have the actual measurements right there when they do the computerized imaging of each stone when it is graded???
Thank you for all your help!

 

[jp201845]

Do you think the GIA Facetware is more accurate? It gives more specific measurements for my stone than does my report (more like an AGS report). If I go by that, the depth on my stone isn’t as bad
But, interesting, Facetware gives my diamond a 62.7 but has 63 on the report, yet I’ve seen other reports on other stones (incl. my sister in law’s with a 62. that state 62.7, etc. and they aren’t rounded on the report. In the case of my sister-in-law’s, her’s is an older report (the blue reports) so I thought maybe GIA wasn’t rounding back then. Yet I’ve seen many stones recently online that didn’t round up to 63 as described above on the newer reports (the brown/gold color). Any insight into this?? (P.S. My sister-in-law’s report is from AFTER they began doing cut grading.)
Furthermore, regarding the rounding, on the Facetware it states 15.8 vs 16 on my report, as well as 42.9 vs 43. So would these non-rounded numbers be the actual measurements? If so, why would GIA “take the time” to round when they have the actual measurements right there when they do the computerized imaging of each stone when it is graded???
Thank you for all your help!

To my knowledge GIA still continues to round angles but I'm not sure of the depth % if that is accurate but I'm assuming it is. The best person to answer your questions in a more technical manner would be @Karl_K since he is the expert. On a side note not exactly sure how reliable GIA Facetware program is ....

 

[headlight]

Thanks so much for all your help and knowledge!

 

[flyingpig]

If so, why would GIA “take the time” to round when they have the actual measurements right there when they do the computerized imaging of each stone when it is graded???

Reason 1. Measurement Uncertainty, Accuracy, and Precision: GIA has multiple labs throughout the world. In addition, there are thousands of vendors and manufacturers with different measuring tools and technicians.

Reason 2. Practicality: The crown angle and pavilion angle are reported to the nearest 0.5 and 0.2 degree. If they are to be rounded to the nearest 0.1 degree, the sample and data size required for creating cut grading system increase by 10 fold. That's alot of work.
We, PSers and trade members, know that every 0.1 degree counts. But it is relevant in certain ranges and for certain combinations of crown and pavilion angles only such as PA 40.3~40.6, PA 40.8~41.2, CA 35~36. Outside these ranges, MRBs behaves very predictably. A MRB with 36/41.4 will appear very similar to a MRB with 35.5/41.2; both with no contrast and with alot of leakage.

 

[Karl_K]

Where are you seeing the GIA Facetware? I checked a couple links and didn't see it.
As far as I know GIA does not release any information other than that on the report.
However there is a facetware option in the scanners so that could be where it came from, the sellers scanner.
I would not expect that big a difference in depth% however.

John or Neil is more up on what GIA is doing than I am.
Since I'm not actively slinging diamonds at this time, I dont pay a lot of attention to what they are doing.
@John Pollard
@denverappraiser

 

[headlight]

Where are you seeing the GIA Facetware? I checked a couple links and didn't see it.
As far as I know GIA does not release any information other than that on the report.
However there is a facetware option in the scanners so that could be where it came from, the sellers scanner.
I would not expect that big a difference in depth% however.

John or Neil is more up on what GIA is doing than I am.
Since I'm not actively slinging diamonds at this time, I dont pay a lot of attention to what they are doing.
@John Pollard
@denverappraiser

John, I just got it through the GIA website! Even a google search for it takes you right to the page!

 

[headlight]

Sorry, meant to say Karl!

 

[headlight]

Reason 1. Measurement Uncertainty, Accuracy, and Precision: GIA has multiple labs throughout the world. In addition, there are thousands of vendors and manufacturers with different measuring tools and technicians.

Reason 2. Practicality: The crown angle and pavilion angle are reported to the nearest 0.5 and 0.2 degree. If they are to be rounded to the nearest 0.1 degree, the sample and data size required for creating cut grading system increase by 10 fold. That's alot of work.
We, PSers and trade members, know that every 0.1 degree counts. But it is relevant in certain ranges and for certain combinations of crown and pavilion angles only such as PA 40.3~40.6, PA 40.8~41.2, CA 35~36. Outside these ranges, MRBs behaves very predictably. A MRB with 36/41.4 will appear very similar to a MRB with 35.5/41.2; both with no contrast and with alot of leakage.

Obviously AGS was able to “put in the work” to create an accurate system!

 

[Karl_K]

I just got it through the GIA website! Even a google search for it takes you right to the page!

I thought you were talking about a specific diamonds information coming up in it?

 

[kmajid]

Anyone happen to have an opinion on this stone? For some reason HCA won’t give me a score. Thanks in advance.

https://www.bluenile.com/diamond-details/LD12389218

 

[lovedogs]

Anyone happen to have an opinion on this stone? For some reason HCA won’t give me a score. Thanks in advance.

https://www.bluenile.com/diamond-details/LD12389218

Nope, scores over 2. You need to put in the dimensions of the stone and all the info about depth, angles, table, etc. Your life will be much easier if you use the PS search tool

 

[headlight]

I thought you were talking about a specific diamonds information coming up in it?

yes... when I enter the data off of a lab report.

 

[John P]

Do you think the GIA Facetware is more accurate? It gives more specific measurements for my stone than does my report (more like an AGS report). If I go by that, the depth on my stone isn’t as bad
But, interesting, Facetware gives my diamond a 62.7 but has 63 on the report, yet I’ve seen other reports on other stones (incl. my sister in law’s with a 62. that state 62.7, etc. and they aren’t rounded on the report. In the case of my sister-in-law’s, her’s is an older report (the blue reports) so I thought maybe GIA wasn’t rounding back then. Yet I’ve seen many stones recently online that didn’t round up to 63 as described above on the newer reports (the brown/gold color). Any insight into this?? (P.S. My sister-in-law’s report is from AFTER they began doing cut grading.)
Furthermore, regarding the rounding, on the Facetware it states 15.8 vs 16 on my report, as well as 42.9 vs 43. So would these non-rounded numbers be the actual measurements? If so, why would GIA “take the time” to round when they have the actual measurements right there when they do the computerized imaging of each stone when it is graded???
Thank you for all your help!

Depth %, crown height % and pavilion % are more accurate a diamond's printed report. Scroll down to "Total depth, Crown Height, and Pavilion Depth" explanations on this page.
https://www.gia.edu/facetware-help

FYI: The numbers on the report can provide context clues as to which way angular data was rounded, but it's not an exact science -

Reason 1. Measurement Uncertainty, Accuracy, and Precision: GIA has multiple labs throughout the world. In addition, there are thousands of vendors and manufacturers with different measuring tools and technicians.

+1

 

[Linny]

Reason 1. Measurement Uncertainty, Accuracy, and Precision: GIA has multiple labs throughout the world. In addition, there are thousands of vendors and manufacturers with different measuring tools and technicians.

Reason 2. Practicality: The crown angle and pavilion angle are reported to the nearest 0.5 and 0.2 degree. If they are to be rounded to the nearest 0.1 degree, the sample and data size required for creating cut grading system increase by 10 fold. That's alot of work.
We, PSers and trade members, know that every 0.1 degree counts. But it is relevant in certain ranges and for certain combinations of crown and pavilion angles only such as PA 40.3~40.6, PA 40.8~41.2, CA 35~36. Outside these ranges, MRBs behaves very predictably. A MRB with 36/41.4 will appear very similar to a MRB with 35.5/41.2; both with no contrast and with alot of leakage.

I have a stone that has (GIA) angles 34.5 and 41 and it gets a HCA score of 1.7? Doesn’t this combo indicate potential light leakage? Why doesn’t it score over 2?

 

[headlight]

I have a stone that has (GIA) angles 34.5 and 41 and it gets a HCA score of 1.7? Doesn’t this combo indicate potential light leakage? Why doesn’t it score over 2?

How do you feel about it’s performance?

 

[lovedogs]

I feel like we've gone really off topic here, and should keep this thread about OP.

 

[headlight]

My apologies to OP & contributors.

 

[flyingpig]

I think the discussion is still relevant for OP.
Many of stones mentioned in this thread have CA 34~36.5 and PA 40.6~41 and score somewhat decently in HCA close to 2.0, they appear attractive in videos and photos. But the combination of different CA and PA and every 0.5 and 0.1 degree can make huge difference in the world of ideal cut diamonds, as he/she is finding out in the new thread. https://www.pricescope.com/community/threads/invalid-measurement-in-hca.250180/

 

[Linny]

I have a stone that has (GIA) angles 34.5 and 41 and it gets a HCA score of 1.7? Doesn’t this combo indicate potential light leakage? Why doesn’t it score over 2?

Sorry you are right! I didn’t mean to take the post off topic. I apologize. On the question of stones not coming up in the HCA tool I just put the dimensions in manually, like was mentioned, and it always seems to work that way.

 

[kmajid]

My apologies to OP & contributors.

That's silly. A lot of valuable information has been shared, which has been incredibly helpful! Appreciate the courtesy. This platform and its people are absolutely fantastic!

Sincerely appreciate everyone.