Expert opinion on this round brilliant please

[djm111]

Hi All,

Im looking for some feedback on this diamond''s numbers. Sorry, I do not have any images at this time. The stone is I color, vs2 clarity, excellent cut, excellent symmetry and excellent polish.

GIA Cert
1.249 Round Brilliant
Diameter: (6.89-6.92) 6.91
Table Size: 58.9
Crown Angle: 33.94
Pavilion Angle: 40.67
Star Length: 58.4
Lower Halves: 72.9
Girdle Minimum: 1.82
Girdle Maximum: 2.68
Culet: none
Crown Height: 13.67
Pavilion Depth 42.82
Total Depth: 60.8

 

[stone-cold11]

Numbers looks good.

This is a sarin scan of the stone? GIA numbers are not that precise.

 

[Lorelei]

Date: 7/13/2009 2:14:44 PM
Author:djm111

Hi All,

Im looking for some feedback on this diamond's numbers. Sorry, I do not have any images at this time. The stone is I color, vs2 clarity, excellent cut, excellent symmetry and excellent polish.

GIA Cert
1.249 Round Brilliant
Diameter: (6.89-6.92) 6.91
Table Size: 58.9
Crown Angle: 33.94
Pavilion Angle: 40.67
Star Length: 58.4
Lower Halves: 72.9
Girdle Minimum: 1.82
Girdle Maximum: 2.68
Culet: none
Crown Height: 13.67
Pavilion Depth 42.82
Total Depth: 60.8

Welcome!

The diamond looks good, well worth further investigation. I would assume these are the Sarin results for this diamond?

 

[djm111]

Yes, these numbers are from the sarin report. I asked the vendor for this report because I was concerned about the pavilion angle on the stone. GIA gave it a 40.6 and I know that if a stone''s pavilion angle ends in an odd number the GIA will round up. So, I was worried that the pavilion angle might have actually been 40.5, but thankfully it was closer to 40.7. Also, I viewed the stone under an idealscope and it looked great to my amateur eyes, it had great arrows and there didnt seem to be any light leakage (again I havent looked at many "real life" idealscope images). So, this stone should be a safe bet? It looked great in person under a bunch of different lighting conditions...Nice and bright.

 

[Lorelei]

Date: 7/13/2009 2:29:52 PM
Author: djm111
Yes, these numbers are from the sarin report. I asked the vendor for this report because I was concerned about the pavilion angle on the stone. GIA gave it a 40.6 and I know that if a stone''s pavilion angle ends in an odd number the GIA will round up. So, I was worried that the pavilion angle might have actually been 40.5, but thankfully it was closer to 40.7. Also, I viewed the stone under an idealscope and it looked great to my amateur eyes, it had great arrows and there didnt seem to be any light leakage (again I havent looked at many ''real life'' idealscope images). So, this stone should be a safe bet? It looked great in person under a bunch of different lighting conditions...Nice and bright.

Sounds good and yes the diamond definitely sounds like a real contender!

 

[djm111]

I noticed that the star length on this stone seems to be a little higher than other stones that I looked at. What does this mean in relation to the other proportions on this diamond? In other words, how will this number affect the performance of this diamond (i.e. fire, brightness, and scintillation)? I know that the table percentage is a little high so will the star length help this stone out in that category. Also, I am not familiar with the lower half number which I listed. What is this and how does it play into the performance of this diamond?

 

[Lorelei]

Date: 7/13/2009 2:46:13 PM
Author: djm111
I noticed that the star length on this stone seems to be a little higher than other stones that I looked at. What does this mean in relation to the other proportions on this diamond? In other words, how will this number affect the performance of this diamond (i.e. fire, brightness, and scintillation)? I know that the table percentage is a little high so will the star length help this stone out in that category. Also, I am not familiar with the lower half number which I listed. What is this and how does it play into the performance of this diamond?

This link explains more.

http://www.goodoldgold.com/Articles/MinorFacets/

https://www.pricescope.com/community/threads/how-significant-are-the-star-facets-and-lower-girdles-info.31985/

The star and LGF's fine tune the character of the diamond but the main things are the critical angles, these are more important to overall performance than the former, so don't worry too much, these are good to know but don't tell the whole story. The 58% stars are fine. The lower girdle facets can fine tune the type of sparkle you can see in a diamond, generally speaking thicker/ shorter LGF's can show more chunky broad flashes, thinner/ longer LGF's pin/ sharp sparkle put in very basic terms. Also if you see a diamond with an arrow pattern, shorter LGFs produce thicker arrows, longer thinner arrows. See the first link for diagrams which will make this much clearer.

* quote from above link GOG*

"The star facets are the windows to the hot spots (blacks observed in LightScope analysis) between the arrow heads which are directly influenced by the lower girdle facet length. When diamonds have proper lower girdle facet length, opening these windows increases the *sparks* that fly out from between the fiery arrows, thus increasing both fire and scintillation as observed in direct light conditions. Closing these windows decreases that optical effect. GIA's most recent research shows exactly what I've been discovering concerning this phenomena. Here are examples of diamonds with varying star/upper girdle ratios. ( see this quote and diagrams in GOG link).

The thing to be learned from the above graphic is how the light return through the stars are directly affected by the lower girdle facet lengths. The 2nd and 4th stones have identical star facet lengths yet one has distinct dark blacks at the stars while in the other the blacks are non-existent. The thickness of the pavilion mains are also notably different in the 2 stones which is directly affected by lower girdle facet cutting as well."

 

[djm111]

Thanks for all of the comments. One more question. This stone has a very small cloud listed to the upper right of the center of the stone on the table view diagram of the GIA report. Now, this is a vs2 clarity diamond. I cannot see the cloud with my eyes nor could I locate it with a loupe. So, will this cloud affect the light return of the diamond?

 

[Lorelei]

Date: 7/13/2009 3:16:34 PM
Author: djm111
Thanks for all of the comments. One more question. This stone has a very small cloud listed to the upper right of the center of the stone on the table view diagram of the GIA report. Now, this is a vs2 clarity diamond. I cannot see the cloud with my eyes nor could I locate it with a loupe. So, will this cloud affect the light return of the diamond?

Shouldn''t be an issue with VS2.

 

[stone-cold11]

nope, not an issue with VS2.

 

[djm111]

One last Question. Is a 40.67 pavilion angle a nice angle to have on a diamond? Also, does the 40.67 pavilion angle pair well with the 33.94 (34) crown angle?

 

[Lorelei]

Date: 7/13/2009 3:31:50 PM
Author: Lorelei

Date: 7/13/2009 3:16:34 PM
Author: djm111
Thanks for all of the comments. One more question. This stone has a very small cloud listed to the upper right of the center of the stone on the table view diagram of the GIA report. Now, this is a vs2 clarity diamond. I cannot see the cloud with my eyes nor could I locate it with a loupe. So, will this cloud affect the light return of the diamond?

Shouldn''t be an issue with VS2.

Just reading up on grade setting clouds in VS2, according to one of the experts they are not usually an issue with VS2 but the advice given is to check anway to be sure. So ask the vendor to check it isn''t visible or impacting brilliance to be on the safe side.

 

[Lorelei]

Date: 7/13/2009 4:40:09 PM
Author: djm111
One last Question. Is a 40.67 pavilion angle a nice angle to have on a diamond? Also, does the 40.67 pavilion angle pair well with the 33.94 (34) crown angle?

40.7 is a great pav angle with most crown angles ( you have far more flexibility with crown angle than pavilion) and it is also a good balance for the crown angle here. Excellent combo.

 

[djm111]

great news...Thanks all.

 

[Lorelei]

Date: 7/13/2009 4:47:09 PM
Author: djm111
great news...Thanks all.

Most welcome and let us know how you get on

 

[stone-cold11]

Date: 7/13/2009 4:40:09 PM
Author: djm111
One last Question. Is a 40.67 pavilion angle a nice angle to have on a diamond? Also, does the 40.67 pavilion angle pair well with the 33.94 (34) crown angle?

Within the AGS Ideal, GIA Ex cut range.

 

[djm111]

Date: 7/13/2009 4:41:15 PM
Author: Lorelei

Date: 7/13/2009 3:31:50 PM
Author: Lorelei

Date: 7/13/2009 3:16:34 PM
Author: djm111
Thanks for all of the comments. One more question. This stone has a very small cloud listed to the upper right of the center of the stone on the table view diagram of the GIA report. Now, this is a vs2 clarity diamond. I cannot see the cloud with my eyes nor could I locate it with a loupe. So, will this cloud affect the light return of the diamond?

Shouldn''t be an issue with VS2.

Just reading up on grade setting clouds in VS2, according to one of the experts they are not usually an issue with VS2 but the advice given is to check anway to be sure. So ask the vendor to check it isn''t visible or impacting brilliance to be on the safe side.

Lorelei - Not sure what the term "grade setting" refers to. A little more information, in addition to not being able to see the cloud with my naked eye or the loupe, I was also not able to view it with the idealscope. Does the fact that the cloud is hard to find help in relation to its impact on brilliance?

 

[Lorelei]

Date: 7/13/2009 5:24:34 PM
Author: djm111

Date: 7/13/2009 4:41:15 PM
Author: Lorelei

Date: 7/13/2009 3:31:50 PM
Author: Lorelei

Date: 7/13/2009 3:16:34 PM
Author: djm111
Thanks for all of the comments. One more question. This stone has a very small cloud listed to the upper right of the center of the stone on the table view diagram of the GIA report. Now, this is a vs2 clarity diamond. I cannot see the cloud with my eyes nor could I locate it with a loupe. So, will this cloud affect the light return of the diamond?

Shouldn't be an issue with VS2.

Just reading up on grade setting clouds in VS2, according to one of the experts they are not usually an issue with VS2 but the advice given is to check anway to be sure. So ask the vendor to check it isn't visible or impacting brilliance to be on the safe side.

Lorelei - Not sure what the term 'grade setting' refers to. A little more information, in addition to not being able to see the cloud with my naked eye or the loupe, I was also not able to view it with the idealscope. Does the fact that the cloud is hard to find help in relation to its impact on brilliance?

Grade setting means the reason for the VS2 grade, in other words the diamond was graded VS2 because of this cloud. I was reading up as it was at the back of my mind I needed to double check, and read the opinion of one of the experts, apparently VS2 clouds are not normally an issue but it is prudent to check with the vendor or appraiser that the cloud isn't visible or impacting brilliance - like I said very rare in VS2 but best to check.

 

[stone-cold11]

If an inclusion is grade setting, it will be mark on the inclusion map with the most important inclusions listed first, unless it is listed in the comment as grade setting inclusion not shown.

 

[djm111]

Date: 7/13/2009 5:39:11 PM
Author: Stone-cold11
If an inclusion is grade setting, it will be mark on the inclusion map with the most important inclusions listed first, unless it is listed in the comment as grade setting inclusion not shown.

The cloud is listed first on the inclusion map. Does that mean it is grade setting and if so does that mean that it will affect the light performance? I never even paid any attention to it because it is so small on the inclusion map. I had read that really big clouds are a concern, but the size of this cloud never really struck me as something to be concerned about.

 

[Lorelei]

Date: 7/13/2009 5:48:33 PM
Author: djm111

Date: 7/13/2009 5:39:11 PM
Author: Stone-cold11
If an inclusion is grade setting, it will be mark on the inclusion map with the most important inclusions listed first, unless it is listed in the comment as grade setting inclusion not shown.

The cloud is listed first on the inclusion map. Does that mean it is grade setting and if so does that mean that it will affect the light performance? I never even paid any attention to it because it is so small on the inclusion map. I had read that really big clouds are a concern, but the size of this cloud never really struck me as something to be concerned about.

Inclusions are listed in order of importance. To put this into perspective, it is unlikely the cloud is an issue, but best to check with the vendor to be on the safe side, same as you would with a feather inclusion for example. You would check that a feather isn't in a vulnerable area of the diamond, just check the cloud isn't visible or impacting brilliance. We can't say for sure no as we are not experts nor have we seen the diamond, according to one of our experts it is unlikely to be an issue in VS2 but if he were buying a diamond for himself he would want to double check to be sure.

 

[djm111]

I just want to say thanks to everybody for all of the help during the very complicated process of buying a diamond. As an update, I purchased the stone which is the topic of this thread and I am confident that it be a beautiful center stone for my girlfriend''s engagement ring. Thanks again.

 

[Lorelei]

Date: 7/18/2009 10:31:22 AM
Author: djm111
I just want to say thanks to everybody for all of the help during the very complicated process of buying a diamond. As an update, I purchased the stone which is the topic of this thread and I am confident that it be a beautiful center stone for my girlfriend''s engagement ring. Thanks again.

Many congrats and thanks for the update!!

 

[stone-cold11]

Congrats.