Please Help -- Final Decision!

[fletch173]

After searching several Pittsburgh area B&M family owned jewelers, I''ve found a jeweler that I''m comfortable with [certified gemologist] and I have narrowed it down to a choice between two stones. Here are the details:

Stone 1:
AGS certifed: 01/20/2006 [AGS 0006921906]
7.29x7.32x4.53mm
Cut Grade: NONE
Weight: 1.511 cts.
Depth: 62.1%
Table 54.7%
Pavilion Angle: 40.1
Crown Angle: 36.1
Girdle: Thin to Slighlty Thick, Faceted
Cutlet: Pointed
Polish: Excellent
Symmetry: Excellent
Color Grade (AGS 2.0) -- H
Clarity Grade: (AGS 6.0) -- SI2 (Eye Clean in fact very good clarity and jeweler thinks SI2 is overly critical and I tend to agree based on the stones I''ve looked at in a microscope). Regardless, good SI2
Fluorescence: Negligible
HCA Score: 0.9 Light Return: EX; Fire: EX; Scintillation: Ex; Spread: VG
Price: $8,995
Laser Inscribed
Issue: The lack of an AGS cut grade bothered me and it is due to the date it was certified. i.e. they did not issue cut grades in 2006. The jeweler contacted the lab and they indicated that it would get a cut grade of 3 (sight unseen). He is still trying to follow up and determine why that would be.

Stone #2:
AGS certified: 05/15/2008 [AGS 0009692601]
7.35 - 7.39 x 4.50 mm
Weight: 1.503 cts.
Cut Grade: AGS Excellent 1
HCA Score: 0.4 Light Return: Excellent; Fire: Excellent; Scintillation: Excellent; Spread Very good -- very close to overlapping AGS ideal and GIA excellent range.
Depth: 61.1%
Table: 55.7%
Crown Angle: 34.6
Pavillion Angle 40.5
Color Grade: AGS 2.0 (H)
Clarity Grade: AGS 6 (SI2) -- not as clean as the stone above, but still eye clean.
Fluorescence: Negligible
Price: $9,845 [$850 more than stone 1]
Not laser inscribed

Here is the deal, I''ve looked at these stones at length [in sun light, out of sun light, under different lighting conditions, etc.] and I just really can''t see a difference in cut. The jeweler (licensed gemoligist with GIA) also can not see the difference in cut and thinks they are both excellent in terms of cut. He is not pushing one stone over the other and is completely neutral, stating they are equally priced in terms of his margin. I''d like all opinions and if there is someone from AGS that participates in this forum, it would be great to get there take on stone #1. Bottom line, is stone #2 worth an extra $850? Thanks for your help!

 

[stone-cold11]

I think it is probably due to the deeper nature of stone 1. For a larger stone, it has a smaller apparent size top down and also steeper crown angle, outside of AGA's premier cut ratio, rated 2B cut I think. Probably that's why when AGS was call up and given the numbers, they gave it a cut grade of 3. They didn't do a optical test of it before 2006 I think so they probably do not have an idea of it's real optical performance. That is probably also the reason it was cheaper compared to the other smaller stone but same clarity and color grade.

I would go for stone 1, reason being I prefer a more eye-clean stone. :p Just my 2cents opinion.

 

[Lorelei]

Hi Fletch,

I prefer the second one as the angles are in a '' safer '' range, the pavilion angle is shallow on the first diamond, so I would check that one out very carefully in as many different lights as possible to make sure still looks good.

 

[fletch173]

Thanks for the input! Still not sure which way I will go, but if I do go with stone #2 is it worth having it laser inscribed. I think the jeweler said he would need to send it out and it would cost about $200. Thanks.

 

[UCLABelle]

Stone # 2 seems a bit safer. I would also have it laser inscribed...but that is just my opinion.

 

[John P]

Issue: The lack of an AGS cut grade bothered me and it is due to the date it was certified. i.e. they did not issue cut grades in 2006. The jeweler contacted the lab and they indicated that it would get a cut grade of 3 (sight unseen). He is still trying to follow up and determine why that would be.

Poppycock.

The AGS lab has issued cut grades since 1996. It sounds like a DQR was requested for that diamond instead of a DQD. Look on the report and I suspect it will say "Diamond Quality Report." The AGS report for diamond 2 with the cut grade will say "Diamond Quality Document."

The lab told your jeweler diamond 1 would receive AGS3 based on its major angles. 55, 40.1, 36.1 is predicted as AGS3 in light performance (I have attached the relevant chart from the AGS Cutting Guides, below). You and your jeweler may be interested in knowing that combination would receive VG in cut from GIA (depending on minor facets and brillianteering).

I agree with your jeweler that AGS is pretty strict on clarity. Those eye-clean SI2 grades are nice for clients.

I have not seen these diamonds but I've seen plenty near these basic numbers. Something you need to be aware of is that pavilion angles in this range - paired with those crown angles - are subject to a degree of "head shadow" (also called obstruction or obscuration). Diamond number 1 especially; ergo the lower performance grade. What is obstruction? Naturally your head blocks some of the light getting to the diamond causing parts of it to darken. This is good because it creates contrast between light and dark areas (GIA calls it pattern). As the diamond is tilted those light and dark areas reverse themselves, contributing to scintillation.

Diamonds with shallow pavilions, coupled with certain crowns, pick up more of your head's shadow, especially as you move closer to the diamond. In fact, if you look at this HCA page you will see a graphic indicating "young people rings," "older people rings," and "pendant and earring stones." This follows the cutters line relative to obstruction: Younger rings show the least obstruction (presuming young people will look more closely at their rings), older show slightly more (close-up vision isn't as good in most elders) and pendant/earring stones gather enough obstruction that the author recommends they be used in capacities where head shadow has less effect...for example most people don't "obstruct" a pendant diamond with their heads - unless they are getting pretty fresh.

Based on the numbers I would not select diamond 1 for an engagement ring. I would look at diamond 2 with the obstruction effects in mind, although I've seen wonderful diamonds at this configuration. The minor facets (lower halves especially) can help with this. In short, I suggest you compare diamond 2 to another top cut and check out the head shadow issue. If it's not a concern that would be my recommendation from these you have put forward.

 

[fletch173]

John -- thanks so much for your time and fantastic input. You are exactly right regarding the reports (hadn''t noticed). Dimaond #1 report is a ''Diamond Quality Report'' and Diamond #2 is a "Diamond Quality Document''. The one item I don''t want to compromise on is the cut, and for this reason, I will likely eliminate diamond #1 from the selection process. As a side note, I looked at several ''excellent'' cut GIA diamonds that I''ve elminated because they did not score well on HCA and I did not like the cut as much. If I go with diamond #2 (which is likely), do you think it is worth paying money to have it laser inscribed? Also, assuming I''m OK with the ''shadow'' issue, is there are big difference in cut between AGS1 and AGS0, would it be noticeable? Again, thanks very much for your input!

 

[John P]

Date: 9/19/2008 1:56:44 PM
Author: fletch173
John -- thanks so much for your time and fantastic input. You are exactly right regarding the reports (hadn't noticed). Dimaond #1 report is a 'Diamond Quality Report' and Diamond #2 is a 'Diamond Quality Document'. The one item I don't want to compromise on is the cut, and for this reason, I will likely eliminate diamond #1 from the selection process. As a side note, I looked at several 'excellent' cut GIA diamonds that I've elminated because they did not score well on HCA and I did not like the cut as much. If I go with diamond #2 (which is likely), do you think it is worth paying money to have it laser inscribed? Also, assuming I'm OK with the 'shadow' issue, is there are big difference in cut between AGS1 and AGS0, would it be noticeable? Again, thanks very much for your input!

You're welcome.

GIA EX includes some deeper combos I am not a fan of because they have light leakage.

I looked diamond 2's info up on the AGS site (here). The general numbers put it on the border of AGS0 and 1 for light performance and I think the lower girdle facet length will help mitigate obstruction in this configuration. Do you have the full breakdown of grades? There is a possibility that it received a 1 in polish or symmetry and still got the 0 in light performance.

AGS0 and AGS1 performance differences may be visible or invisible to your eye in the same way VS2 and SI1 can appear identical or different; it depends on the specifics of the stones. In human terms most normal people would be hard pressed to differentiate a single grade without training or acute perception. AGS1 is an extremely good grade, far above average. No matter what input I give though, you're in the best position to make the choice. Do take time to check the effects of head shadow in several lighting conditions and distances, compared to another top candidate.

Laser inscription is useful if you want a quick way to ID your diamond with loupe or scope. However the SI2 inclusions and accompanying plot will be a much more reliable way to do this professionally. Inscriptions can be polished off, but those characteristics were cooked by mama nature and aren't likely going anywhere. It's really whatever you want to do.

 

[customandrew]

"for example most people don''t "obstruct" a pendant diamond with their heads - unless they are getting pretty fresh. "-Pollard...

hahaha...

 

[fletch173]

Thanks, John. I just sent an e-mail to the jeweler requesting a further breakdown of the cut grade since it does not appear on my DQD. Also, your thoughts on laser inscription were helpful. --Scott

 

[fletch173]

Here is the breakout of the score from AGS:

The polish is 0, symmetry is 0, light performance is 1. Cut grade is
1 (excellent).