Judge Cut Purely on the Numbers

[orgopeach]

I''m in the market for an e-ring. I have researched the PS website and as a result of my newfound knowledge and interest ordered the IS and ASET scopes. I am scheduled to visit with a jeweler - (recommended by a friend) in the LA jeweler district mid-December. (I also plan to visit Eli''s and Oscar''s.) In the meanwhile, I have been window-shopping online at GOG, WF, and JA. My criteria is 1.35-1.55c, D-F, and IF-VS1. To do a preliminary analysis of the cut, I am running the measurements of the rock through AGA Grader and the HCA. Basically, I want the rock to have the best fire, brillance, and scillitation for my budget <20k. Is this the best way to screen the rocks before I actually look at them in person or order them to view?

To me, the numbers look good for this one. ~15.5k
http://www.goodoldgold.com/diamond/5062

However, the LA jeweler''s rocks look crappy by the numbers. Attached is GIA report. Over the phone, she keeps mentioning triple excellent, ideal cut, and H&A. I believe the price is ~12.5k.

 

[stone-cold11]

At 61.6% depth, 57% table, 35° crown angle, 40.8° pavilion angle, it score a HCA = 1.6.

Looks great to me for cut. Why do you say it is not?

EDT to add:

I see, the GOG stone score a 1.1. But you are not suppose to judge a stone by the score, only to remove the non-performing ones, which to us is anything > 2. So 1.1 vs 1.6 is not really any indications of performance, some people will like 1.1 some 1.6 some 0.5 etc...

And the Price looks great too. A JA 1.3c F VVS1 is price around 18k.

 

[neatfreak]

Both stones look like they are likely to be beautiful...not sure what you mean by one looking crappy by the numbers? If these are the two in question they both look really nice.

 

[Regular Guy]

Date: 12/9/2008 4:45:58 PM
Author:orgopeach
To do a preliminary analysis of the cut, I am running the measurements of the rock through AGA Grader and the HCA. Basically, I want the rock to have the best fire, brillance, and scillitation for my budget <20k. Is this the best way to screen the rocks before I actually look at them in person or order them to view?

To me, the numbers look good for this one. ~15.5k
http://www.goodoldgold.com/diamond/5062

Yes and no. Yes, the principle is good. But save yourself some time and rework the procedure. I found that (single) one in a couple of seconds, using this.

I do find, though, JA is not reliably included in that db...so you may have to...as you''ve been doing...search them manually. Or...decide as I do...to only look there for AGS0 options. When you find them...ignore running the HCA, because the AGS0 documentation is more conclusive to begin with.

 

[orgopeach]

Will a better HCA score <>definitely[/b] mean a better fire, brilliance, and scintillation?

 

[John P]

Date: 12/10/2008 12:29:29 AM
Author: orgopeach
Will a better HCA score <>definitely[/b] mean a better fire, brilliance, and scintillation?

A number
It is an absolutely useful tool for identifying diamonds predicted to perform versus those that likely won't, but Garry's instructions to use it for rejection (not final selection) are key: http://diamonds.pricescope.com/ideal.asp

As a comparison, you can use a chalk outline to predict how someone will look, but it gives limited info.

 

[swingirl]

Stones that score 2 and below are considered Excellent (by the HCA grading scale) and worth investigating further. Since the score is arrived at by an average of 4 things the variation between 0 and 2 is due to the stone scoring differently in the categories. One stone might score higher in Fire but lower in Light Return. Another could score high in Scintillation but lower in Fire. So 1.9 isn''t better or worse than 0.9, they are just different. Some people have preferences. And some people have found stones they love that scored in the 2-3 range. But they saw them in person and made their choice based on what their eyes liked.

I hope this helps.

 

[Lorelei]

Date: 12/9/2008 4:45:58 PM
Author:orgopeach
I''m in the market for an e-ring. I have researched the PS website and as a result of my newfound knowledge and interest ordered the IS and ASET scopes. I am scheduled to visit with a jeweler - (recommended by a friend) in the LA jeweler district mid-December. (I also plan to visit Eli''s and Oscar''s.) In the meanwhile, I have been window-shopping online at GOG, WF, and JA. My criteria is 1.35-1.55c, D-F, and IF-VS1. To do a preliminary analysis of the cut, I am running the measurements of the rock through AGA Grader and the HCA. Basically, I want the rock to have the best fire, brillance, and scillitation for my budget <20k. Is this the best way to screen the rocks before I actually look at them in person or order them to view?

To me, the numbers look good for this one. ~15.5k
http://www.goodoldgold.com/diamond/5062

However, the LA jeweler''s rocks look crappy by the numbers. Attached is GIA report. Over the phone, she keeps mentioning triple excellent, ideal cut, and H&A. I believe the price is ~12.5k.

This could be a good diamond, the angles are hovering around what we call the steep deep zone but not all diamonds will show any darkness or light leakage as a result as GIA rounds the angles. Plus you have your Idealscope to use to see the diamond in person, then you will be able to judge it and see whether it is an option for you. Also unless you wanted VVS clarity then you could drop to VS and still have a very clean diamond, but this is personal preference.