Comparison help please

[Carneios]

Which is better? A 0.90ct G VVS2 or a 0.90ct F VS2?? Help

 

[Anthony Marziatico]

From what I've learned on my brief time on the forums is that people require more measurements than that.

Are you able to post pictures of the GIA reports? Maybe I can start you off in the right direction and then someone can pick up the rest.

 

[Carneios]

Shape: Round Round
Carat: 0.9 0.9
Color: F G
Clarity: VS2 VVS2
Lab: GIA GIA
Cut: Ideal Ideal
Depth: 64.7 66.1
Table: 58 55
Girdle: VeryThick Medium
Culet: None
Polish: VG X
Symmetry: G VG
Fluorescence: N M
Measurements: 5.90 x 5.96 x 3.84 5.91 x 5.95 x 3.92
Crown Angle: 38 39
Crown Depth: -1 -1
Pavilion Angle: 39.6 40
Pavilion Depth: 41.5 0.42
Hearts & Arrows: false false
HCA: EX EX

 

[flyingpig]

Both are not good. They are not well cut.
Do not use HCA on stones that are not GIA ex cut or AGS ideal/ex cut; it fails miserably.

 

[OoohShiny]

38 and 39 crown angle? That is steep!

 

[Carneios]

Both are not good. They are not well cut.
Do not use HCA on stones that are not GIA ex cut or AGS ideal/ex cut; it fails miserably.

I'm confused, because they both say ideal cut. And I don't know what you mean by do not use HCA. Sorry. Just trying to understand.

 

[Carneios]

38 and 39 crown angle? That is steep!

Don't know what that means either. What range should I be searching for then?

 

[flyingpig]

table 54-58, crown 34-35, pavilion 40.6-40.8, depth less than 62.3
Something like this..
https://www.jamesallen.com/loose-di...g-color-vs2-clarity-excellent-cut-sku-3081352

 

[Carneios]

table 54-58, crown 34-35, pavilion 40.6-40.8, depth less than 62.3
Something like this..
https://www.jamesallen.com/loose-di...g-color-vs2-clarity-excellent-cut-sku-3081352

That is a beauty, but about $2,000 more than my budget.

 

[flyingpig]

With 3k budget, you need to downgrade your carat, color and clarity.
0.9c G VS is not realistic.

https://www.jamesallen.com/loose-di...h-color-vs2-clarity-excellent-cut-sku-3193741

 

[LLJsmom]

Please read for basic info about choosing a beautiful modern round brilliant diamond.

With rounds:
The entire purpose of faceting a diamond is to reflect light.
How well or how poorly a diamond does this determines how beautiful it is.
How well a diamond performs is determined by the angles and cutting. This is why we say cut is king.
No other factor: not color, not clarity has as much of an impact on the appearance of a diamond as its cut. An ideal H will out white a poorly cut F. With round diamonds even a GIA triple Excellent is not enough. And you must stick to GIA and AGS only (HPD in Europe is good as well). EGL is a bad option: https://www.pricescope.com/community/threads/egl-certification-are-any-of-them-ok.142863/
So how to we ensure that we have the right angles and cutting to get the light performance we want?
https://www.pricescope.com/wiki/diamonds/diamond-cut
Well one method is to start with a GIA Ex, and then apply the HCA to it. YOU DO NOT USE HCA for AGS0 stones generally, though you can. In general, AGS0 trumps HCA though as one examines the actual stone and the other does not.
https://www.pricescope.com/wiki/diamonds/holloway-cut-advisor
The HCA is a rejection tool. Not a selection tool. It uses 4 data points to make a rudimentary call on how the diamond may perform.
If the diamond passes then you know that you are in the right zone in terms of angles for light performance. Under 2 is a pass. Under 2.5-2.1 is a maybe. 2.6 and over is a no. No score 2 and under is better than any other.
Is that enough? Not really.

So what you need is a way to check actual light performance of your actual stone.
That's what an idealscope image does. https://www.pricescope.com/wiki/diamonds/firescope-idealscope
It shows you how and wear your diamond is reflecting light, how well it is going at it, and where you are losing light return. That is why you won't see us recommending Blue Nile, as they do not provide idealscope images for their diamonds. BGD,BE, James Allen, GOG, HPD, ERD and WF do.

The Idealscope is the 'selection tool'. Not the HCA.
So yes, with a GIA stone you need the idealscope images. Or you can buy an idealscope yourself and take it in to the jeweler you are working with to check the stones yourself. Or if you have a good return policy (full refund minimum 7 days) then you can buy the idealscope, buy the stone, and do it at home.

Now if you want to skip all that... stick to AGS0 stones and then all you have to do is pick color and clarity and you know you have a great performing diamond. Because AGS has already done the checking for you. That's why they trade at a premium. Some AGS0's are better than others though, so pay attention to any ASET or IS provided.

In general with rounds, you will want a table 60% or less. A depth between 59 and 62.4. Crown angle 33.5-35. Pavilion Angle: 40.6-41 (there is a little give on this). And the crown and pavilion angles must be complimentary which is what the HCA checks for you.

 

[ringo865]

GIA does not have an "ideal" cut grade. So there's a red flag. Both are way too deep if that's correct. 64.7 and 66.1. It should be 62.4 max. Other problems addressed above, along with a tutorial on what to look for. Your budget and/or expectations may need a tweak.

You undoubtedly came to the right place to get a beautiful stone. Keep looking.