Why did I pick a GIA VG cut over a GIA exc cut? Am I Nuts?

[checkers]

I've been reading here for a while absorbing all of the information. I chose to buy the diamond from a local jeweler (in the LA jewelry district) who also is doing two custom rings for me. Fortunately, the jeweler understands that cut is very important to me and has let me look at lots of diamonds under the idealscope.

In all, I looked at approximately 20 stones (all GIA Exc or GIA VG cut) with the idealscope, loupe, and the naked eye. I ignored the certificates during my final selection, and was quite surprised to learn that the stone that I most preferred was rated a GIA very good cut. I purchased this stone, which was actually about $400-$500 less than some of the others, based solely on my preference for it.

Predictably, I'm now having some buyer's remorse and have been plugging all the numbers for this stone into various online cut calculators to see if I got a subpar cut stone. Here's what I've found:

HCA - This stone ranks a 0.5 on the HCA. I do understand that most people prefer a diamond with an HCA of 1-2, but I'm under the impression this is still very good.

GIA - I've played with the GIA calculator and determined that the pavilion angle for this stone is 0.2 degrees from being rated a GIA excellent cut (40.4 = very good, 40.6 would be excellent). Obviously, the cutoff has to happen somewhere, but I do wonder about uncertainty in a pavilion angle measurement. Also, it seems there is a very large range of cuts that falls into the GIA very good category, and this one is quite close to the top of the VG category.

AGS - This is a GIA stone, however, looking at the AGS cut ranking tables in a Peter Yantzer pdf file (found via google) leads me to believe this stone would be rated an AGS1. This further leads me to believe that this is not a perfect cut, but is extremely close.

The stats on the diamond are below. At this point, I'm wondering if I should trust my eyes & judgment or if I should just get an AGS0 cut stone and be done with it. The diamond I picked looked very good on the ideal scope and to my eyes, but I'm wondering if there's some aspect of cut that I'm missing or can't assess. I'm also wondering if there is some aspect of this type of cut that appeals to certain people?

Measurements: 6.54 - 6.57 x 3.94 mm, Carat Weight: 1.03
G, SI2
Cut: VG
Depth: 60.1 %, Table: 56 %
Crown Angle: 34.5°, Crown Height: 15 %
Pavilion Angle: 40.4°, Pavilion Depth: 42.5 %
Star length: 50 %
Lower Half: 70 % (I'm not clear on this measurement, but based on the Yantzer pdf it does impact cut rating and 70% is low, normal is 80%)
Girdle: Thin to Medium, Faceted
Culet: None
Polish: VG, Symmetry: Exc

 

[ML2014]

Hi Checkers-

I am not an expert, but I am someone who went through a very similar experience. I checked out a number of stones, mostly GIA excellent cuts, but could not take my eyes off of one particular VG cut. It has just about the same stats as the one you selected (same CA, same PA, mine has a depth of 61.2% and my lower girdle facets are 85%).

I too started thinking that I made the wrong choice (especially after obsessing over all of the numbers), so I went back to my local jewleler to see more excellent cut stones. Could I see a difference? Maybe, but nothing that was appreciable. Bottom line is, I really love my diamond, and as with most things, when you purchase a diamond I think you make tradeoffs. But I am making that sound bad, and I don''t mean to. What I guess I am saying is that I''ve seen GIA excellent cuts that frankly, didn''t look nearly as nice as my stone. If I had gone just for the cut grading, I would have lost a great stone.

So, long story short, I think most folks here will say that you should buy the diamond, not the paper. Most folks rely on the numbers here because they are buying on-line and don''t have the benefit that you and I did of looking at many stones to narrow down to the ones that spoke to us. So the numbers are more crucial in that situation. You looked at I think you said 20 diamonds ? That is great! Did you view the diamonds in various lighting conditions? That is important. If you are still a bit nervous, you might want to get it appraised by an independent appraiser.

Anyway, as I said, I am no expert, but I decided to keep my diamond and everytime I look at it, it amazes me. So no, I don''t think you are crazy at all- I think you you made an infomed choice balancing what was on paper and what you saw with your eyes. Hope this helps! Maybe someone else will chime in.

 

[ML2014]

Oops, and welcome to PS!

 

[JohnQuixote]

You’re not nuts.

Different metrics differ slightly.You interpreted the AGSL file correctly; those numbers are predicted to receive AGS1 per the cut guidelines with 80% lower halves.The lab would have to see it to know how the 70% lowers, optical sym, etc. would figure in.For that matter, GIA rounds several numbers so it could come out as 40.5/34.7 (for example).

Diamonds are cut at many configurations. Being just outside a top grade doesn’t make yours any less beautiful, particularly at the shallow side of GIA EX, which is more weighted toward steep/deep stones than other systems.Keeping this in perspective, it may help to know that diamonds which would receive AGS4-5 if sent to AGSL are common in commercial markets.

If you're interested, here is an example of how a few different systems (AGS, HCA, AGA and GIA) ‘overlap’ – and don’t.

Pavilion angle is what many consider the most critical element.It's usually good for showing where the ‘center’ of different systems lies:For 53-58% tables, pavilion angles 40.6-41.0 have the greatest approval cross-system. The AGS cut guidelines suggest most 0 candidates right in that range. The HCA and AGA prefer the shallow side (and a bit lower). The GIA system prefers the steep side (and higher).

Technically the caution with pavilions at the shallow side is that the shallower you go the more obstruction will occur; darkness caused by the observer blocking light, especially at a close viewing distance.This is why the HCA recommends shallow-pavilioned stones for pendants/earrings - which are worn in such a manner that obstruction is less of an influence - and ‘older people rings’ - because oldsters cannot focus as closely as youngsters [eh, sonny?] so they keep their rings at more of a distance. See the graphic on this page.

Outside the overlap zone the systems don’t unilaterally agree...and neither did you. In this case you were there and voted with your eyes, which is really the most important thing.

Welcome to PS, and you should know that the folks around here are pretty aggressive about seeing pictures of new pet rocks.

 

[devientdrow]

I don''t think you''re nuts! I purchsed from James Allen and he found 2 stones in my budget. One was a slight bit bigger BARELY noticeable in size G/SI2 (eyeclean)/ GIA Ideal cut the SLIGHTLY smaller was a H/SI1/GIa Ideal cut stone. The second slightly smaller stone had a stronger hearts and arrows pattern, and a better clarity. However my husband and I just liked the first one better. It just had something to it that we loved, and I got it. And yes sometimes I would look on here and get enthralled by the listing of "perfect" stats and think to myself, damn did I bypass the BETTER stone? But really both were excellent and the truth is I got an AWESOME stone, no matter what. And it''s the one that "spoke" to us. Who cares if it isn''t as symmetrical as the other....no one is going to come admire my ring with a scope or anything. So it''s up to you. You JUST picked your so if it''s a matter of getting the best value for your money, I can understand you perhaps trying to go back and change it. However if you feel you got your moneys worth and you really like the stone, that don''t worry about it. You mentioned that they all looked good and performed well, trust your instinct.

 

[Pandora II]

When I purchased a diamond for my FBIL, I had a good selection from my wholesaler in Antwerp to choose from. I choose a Very Good in the end as well. There was nothing "off" with the numbers, and it just kept calling me and my ex-boss back again.

FBIL was a bit worried that it didn''t have the ''ideal'' stamp on it, but i just felt it had something extra. It was 1.5ct so quite a big size. he now tells me that it out sparkles most of the other rings he has seen - and in his line of work he sees a lot of expensive bling!

(He was also chuffed that it appraised better than the HRD cert - and was valued at double what I paid (which was true wholesale plus a discount))

 

[Lynn B]

Ditto all the above...and thritto

to the fact that no, you aren't "nuts"!

Believe me, we are hair-splitters to the nth degree around these parts and we totally understand your angst. But there's a huge difference between your purchase and many others here on PS... and that is -- you have seen the diamond.

The numbers that we crunch around here are especially important when buying a diamond "sight-unseen"... it allows the buyer to have a darn good idea of what that stone is going to look like in person. Certain numbers/combos are generally like a little "safety net"... for the buyer who is purchasing a diamond without the benefit of seeing it first. But numbers alone cannot take into consideration the "personality" or minute nuances that make a diamond especially "beautiful" to the beholder.

You have SEEN the stone... and you have compared it to other (well-cut!) diamonds... the diamond "spoke" to you. That is awesome! I would have no second thoughts. I think you have found your perfect stone!

ETA: Now, pictures please!!!

 

[aljdewey]

Honestly, I''d just trust your eyes.

An AGS1 stone is NOTHING to sneeze at, and it obviously appealed to your eyes. Since you''ll look at your DIAMOND much more than you''ll ever look at the paper

, I''d worry more about pleasing your eye.

Congrats on your new stone!

 

[Rhino]

Just some other things you want to think about ...

Shallow angled GIA VG''s will have a great appearance in spot lighting environments. For you to really see why that stone gets a GIA VG, best bet is to make your comparisons in diffuse type lighting.

Most often diamonds observed in jewelry stores are done in spot lighting so your selection doesn''t come at a surprise, so you may want to make this comparison in diffuse lighting before pulling the trigger. If you are indoors in a store you may want to ask if you can see it outside or by a window allowing natural daylight observance. If it''s sunny out stand in the shade for an accurate assessment of brightness.

You may still prefer it but these are some things you may want to do to be sure. If the pavilion angle is indeed 40.4 the ill effects of this will show up in your diffuse environment.

One other perspective (even though you may never be in this situation) but if you''re ever in a position where you want to trade in or sell back a diamond a GIA Ex will always be in higher demand than a VG.

Hope that helps.

 

[checkers]

Wow, thanks everyone for the responses. It really takes a lot of experience to know all the caveats that come with selecting a cut. I''m particularly interested in what everyone said about lighting conditions and viewing distance. Regarding lighting,I looked at the stones in two environments, what I would call an "office" environment (seated at a desk in a room with some windows and overhead fluorescent lighting), and the same environment with a fluorescent desk lamp directly over the stones (~ 20 inches overhead). I''m not sure if either of these would qualify as spot lighting, and I''ve heard some conflicting things on this.

Regarding viewing distance and darkness, I looked at these stones at no more than 10 - 12 inches away. I certainly didn''t hold them at arms length, but I can see how that could make a difference.

I''ve been thinking more about it since my first post, and I''m wondering if spread figured into this as well. The stone I selected has a good spread for the carat weight, and I''m wondering if I went for size. I know that cut is more important than size, but size is such a noticeable attribute it''s hard to overlook. The other variable I didn''t really get into was the clarity. Since I looked at largely SI2 stones I saw a *huge* variety of inclusions, from ones visible to my untrained naked eye, to ones that left me pleasantly surprised at 10x. The stone I picked was truly eye clean and looked very good under the loupe. Obviously, this was a factor as well.

I don''t have any pictures since the ring for the diamond is presently being made. Thanks for all the input, I''m still kind of mulling it over...

 

[marcy]

The visual appearance and performance of a diamond won''t lie; as long as this diamond is what you like; you should be very happy with it and proud of it.