Q on Whiteflash ACA Vs Expert Selection

[mayo1209]

What do you guys think of this diamond. Its specs are:

Total Depth %:61.8
Table %:53.8
Crown Angle:33.0
Pavilion Angle:41.0

Why is this diamond considered outside the AGS0 candidate proportions even though it scores .8 on the HCA. Just trying to understand cut better?


http://www.whiteflash.com/round_ideal_cut/Round-Ideal-Cut-cut-diamond-1987251.htm#

 

[Allison D.]

Howdy Mayo - The two primary factors are the the polish/symmetry grades (excellent instead of ideal) and the shallow crown angle (which demerits the proportions grade to AGS1). I see the girdle is thin-thick, too.

The polish difference doesn't impact the light performance, but it's enough to fall shy of the coveted AGS0 moniker. Performance-wise, the average viewer likely might not see much difference between this one and an AGS0.

If this were a college grade, it would be perhaps a 3.9 or 3.8 - still an A, but just not an A+ (as would be a 4.0).

For someone looking to get the most bang for the budget without paying the AGS0 premium, this would be a great option especially considering how few stones there are in the .90-.99 range.

 

[Kaleigh]

Date: 7/29/2009 9:13:22 PM
Author: Allison D.
Howdy Mayo - The two primary factors are the the polish/symmetry grades (excellent instead of ideal) and the shallow crown angle (which demerits the proportions grade to AGS1). I see the girdle is thin-thick, too.

The polish difference doesn''t impact the light performance, but it''s enough to fall shy of the coveted AGS0 moniker. Performance-wise, the average viewer likely might not see much difference between this one and an AGS0.

If this were a college grade, it would be perhaps a 3.9 or 3.8 - still an A, but just not an A+ (as would be a 4.0).

For someone looking to get the most bang for the budget without paying the AGS0 premium, this would be a great option especially considering how few stones there are in the .90-.99 range.

Great post.

 

[mayo1209]

Alj - thanks for the explanation. Is this a Hearts and Arrows diamond? Or does it lose the H&A because of the symmetry grade being excellent? Does this mean light leaks out of this stone?

 

[jet2ks]

Light performance on the stone, as shown by the Idealscope and ASET images, should be very good. It appears from the photos that this diamond probably misses H&A by a little bit.

 

[Lorelei]

Date: 7/29/2009 10:25:18 PM
Author: jet2ks
Light performance on the stone, as shown by the Idealscope and ASET images, should be very good. It appears from the photos that this diamond probably misses H&A by a little bit.

Ditto, also the proportions would disqualify this diamond from being a WF branded ACA h&a, having said that it looks like a great stone and an excellent example of an ES.

 

[Stone-cold11]

No extra light leakage that I can see from the ASET/IS. Physical symm lab grade those not automatically imply optical symm grade, so an Ex/VG symm lab grade can still have a H&A while an Ideal symm lab grade might not.

 

[Lorelei]

Date: 7/29/2009 9:45:38 PM
Author: mayo1209
Alj - thanks for the explanation. Is this a Hearts and Arrows diamond? Or does it lose the H&A because of the symmetry grade being excellent? Does this mean light leaks out of this stone?

A Whiteflash ACA has not and to the best of my knowledge will not have any less than Ideal for both polish and symmetry ( lab graded) so also because it has excellent symmetry this too will disqualify it from ACA status - there are various reasons including the proportions, girdle etc as explained above why this diamond is not an ACA and the excellent symmetry is another one. Even if it does show hearts and arrows it won't be an ACA anyway because of the above. Symmetry basically means how well the facets, table etc all meet together, this is nothing to do with light leakage. The arrows and hearts you see in some diamonds are down to optical symmetry which is a completely different matter to lab graded symmetry.

http://diamonds.pricescope.com/symm.asp

Alj above basically explained all of this far more succinctly!

 

[treefrog]

Note that according to the AGS report, this is actually an Excellent/Excellent on polish and symmetry.

Treefrog

 

[Stone-cold11]

Date: 7/30/2009 11:36:30 AM
Author: treefrog
Note that according to the AGS report, this is actually an Excellent/Excellent on polish and symmetry.

Treefrog

That don''t actually tell us much as I think for a DQR report max grade is only Ex for polish and symm, never ideal.

 

[Lorelei]

Date: 7/30/2009 11:36:30 AM
Author: treefrog
Note that according to the AGS report, this is actually an Excellent/Excellent on polish and symmetry.

Treefrog

That is the highest you can go Fred on a DQR ( diamond quality report) only DQD( diamond quality documents) get the Ideal grades and these are used for ACA''s, Expert Selection will normally get DQR''s.

 

[Allison D.]

Date: 7/30/2009 11:48:59 AM
Author: Stone-cold11

Date: 7/30/2009 11:36:30 AM
Author: treefrog
Note that according to the AGS report, this is actually an Excellent/Excellent on polish and symmetry.

Treefrog

That don''t actually tell us much as I think for a DQR report max grade is only Ex for polish and symm, never ideal.

That''s correct - while it''s possible that the polish would rank ''ideal'', the highest grade it can receive on the DQR is ''Excellent''.

It looks like we have an error in the listing information on the girdle as well, because the grading report has thin-slightly thick. I''ve asked our folks inside to pulll the data and make the needed corrections.

 

[Allison D.]

Mayo, it might very well have an excellent H&A pattern. We won''t sell it as an H&A because our branded line requires ACAs to earn the AGS0 Platinum DQD report and this stone apparently fell juuuuuuuuuust short of that.

 

[treefrog]

Date: 7/30/2009 11:50:37 AM
Author: Lorelei

That is the highest you can go Fred on a DQR ( diamond quality report) only DQD( diamond quality documents) get the Ideal grades and these are used for ACA''s, Expert Selection will normally get DQR''s.

Interesting... I didn''t know that. Must look into that to increase knowledge base.

I was actually referring to a typo though and Allison promptly took care of that.

Treefred