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CA too low, PA too high. Not worth wasting one of the 3 IS images imho.
 
Sure, I've requested the 3661517 for testing. The others are gone. Out of curiosity, why are they others considered Excellent cut, polish, and symmetry when they have bad angles? Like Why would GIA give them this rating but they have bad angles. Makes it really difficult for non-diamond experts to purchase. and it's not small money. it's not like $500 bucks, its like $10k Plus.
 
If you would be willing to drop to around the 1 carat range, I think this is an absolutely beautiful choice that was recently listed on James Allen:
https://www.jamesallen.com/loose-di...f-color-vs1-clarity-excellent-cut-sku-4977800

In fact, I would snatch that one up in a heartbeat and request an IS. Love the pavilion angle of 40.8 and the overall cut of this diamond. I don't think it will last long.

When looking at GIA-graded stones, I would personally stick to pavilion angles of 40.8, particularly where ASET images are not available (As is the case for most of the non-superIdeal vendors). I know that others on here may disagree, but I really don't trust PAs of 40.6 or 41.0 from GIA due to:

1.) GIA-rounding of pavilion angle averages to the nearest 0.2
2.) Less precision of each of the individual lower half facets in stones that are not cut to the exacting proportions of SuperIdeal stones, and
3.) Low accuracy of the scanning equipment used by GIA to calculate these angles

There's been some rather academic discussions on this very issue in recent weeks here on PS, and also there's older threads that can be dug through with relevant information, but with 40.6 and 41.0 PAs, you run the risk of having a few of the individual lower halves crossing below the 40.45 degree and 41.15 degree marks for the reasons described above, which are very likely to create issues with obstruction and leakage, respectively.

If a stone was precision cut where each lower half facet was cut to 40.6 with very little deviation, then the stone would be an excellent performer if paired with a complementary crown angle. Same goes for a stone with a 41.0 PA. In fact, I would say that, the 41.0/35.0 combo that is the beginning of the "steep-deep" classification could still be a beautiful stone if each of the lower halves were between 40.95 and 41.0. But the average stone being graded by GIA doesn't really have this level of precision, to the point where I would not be comfortable purchasing a stone outside of the 40.8 pavilion angle average if I couldn't get an ASET scope image and also see it in person to test for obstruction issues. With 40.8 average for the lower half angles, there's almost no chance of any individual facet crossing these 40.45 or 41.15 boundaries (unless the stone was absolutely horribly cut, in which case simply looking at the arrows pattern would be a dead giveaway for such a stone :mrgreen:).

With a 40.8 GIA-averaged pavilion angle (which could be anywhere from 40.71-40.89 for the actual average), I think anything between 34.0 and 35.0 GIA-average crown angle makes for a beautiful combo if the IdealScope image looks decent, as there's a lot more leeway with the upper halves if the lower halves are on point. If you look at the angles for most of the branded SuperIdeals, there's quite a bit of variation in the crown angles between 34 and 35 degrees, with each brand seeming to have their own "flavor" that they consider ideal, but almost every stone in their inventories is between 40.7 and 40.9 for the pavilion angles as graded by AGS (with a few having 40.6 if tightly cut).

Not sure if any of this makes sense to you, but I could call on the other experts who have been participating in this discussion to perhaps explain it in slightly simpler terms. @John Pollard? :)

Anyway, for a tl:dr version, look at the stone I posted above. :)
 
DMANonAMission said:
Here are two more
https://www.jamesallen.com/loose-di...f-color-vs2-clarity-excellent-cut-sku-4695331
https://www.jamesallen.com/loose-di...f-color-vs2-clarity-excellent-cut-sku-4977768
Click to expand...
GIA Excellent is a very broad rating that includes some stunning options and some real duds. That is why it is only step 1. Step 2 is look at the angles to be within the ranges posted before in post #14. Step 3 is the HCA tool looking for under 2.0. Step 4 is IS or ASET (better of the two, but not always available). In all of this is also using the videos and photos. I also like H&A images when possible.

#1 has poor angle.
#2 has good angles, but it will tend to have less light return upon close examination (i.e. go grey when your head is close). The inclusions are also black and I find them distracting.

How about these?
https://www.jamesallen.com/loose-di...-color-vvs2-clarity-excellent-cut-sku-4770942
https://www.jamesallen.com/loose-di...f-color-vs1-clarity-excellent-cut-sku-4956910
https://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-3968194.htm {super-ideal that slightly over the budget, but gorgeous}
https://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-3970286.htm {I'd probably choose this G over the F for the size, but that is personal}

From JA, make sure to put a hold on any diamonds you want to pursue of they may disappear.
 
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DMANonAMission said:
Sure, I've requested the 3661517 for testing. The others are gone. Out of curiosity, why are they others considered Excellent cut, polish, and symmetry when they have bad angles? Like Why would GIA give them this rating but they have bad angles. Makes it really difficult for non-diamond experts to purchase. and it's not small money. it's not like $500 bucks, its like $10k Plus.
Click to expand...

This is a complicated question, and comes down to a combination of market forces and also what can be considered "good enough" by most members of the population. By market forces, I simply mean the desire of the diamond industry to get the highest price for the largest percentage of cut rough. Not every rough crystal comes out of the ground looking exactly the same (...because it's a rock. And all rocks don't look the same :mrgreen: ). Therefore, not every rough diamond can be used to create a polished diamond of exacting proportions while simultaneously getting the highest yield from the rough. If GIA said "every diamond must be cut with 61.6% depth 56% table 40.8 Pavilion angles and 34.5 crown angles (not saying this is the best combo, it's just an example) to earn GIA excellent", then there would be a lot of diamonds that wouldn't make the cut (pun intended) and would be viewed as inferior from both a consumer desire standpoint and a marketability and pricing standpoint.

It also comes down to what can be viewed as a range of geometric combinations that will be "good enough" to yield a reasonably decent looking diamond. Here on PriceScope, most (OK all :mrgreen: ) of the regular posters are cut fanatics... To an OCD-scientist level. The truth is that, to most people, simply getting a GIA-excellent diamond will probably be enough to satisfy their "Ohhh look, SPARKLY" desires. And let me be the first to say that pretty much any GIA Excellent will look fantastic next to the un-certed "frozen-spit" that most of the mall stores are peddling as a diamond.

But you're found PriceScope, where GIA excellent alone does not a good diamond make. This truly is a wonderful place, because the wise posters here will help you find a "truly excellent" GIA Excellent among the masses. And as you said, spending $10K is not something to take lightly. A well-cut GIA excellent will look even better than your run of the mill GIA Excellent while costing you about the same (or only a little more). More sparkly-ness for the basically the same price? Who would say no to that? :D
 
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Hey All, got the IS report done. below are the results. What are your thoughts?
 

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I agree with your immediate elimination of #1 (3661517). I stated my thought on both of the others above, but repeating here.
4695331 has poor angles and should be eliminated. {https://www.jamesallen.com/loose-di...f-color-vs2-clarity-excellent-cut-sku-4695331"}

4977768 has good angles, but it will tend to have less light return upon close examination (i.e. go grey when your head is close). The inclusions are also black and I find them distracting as they are mirrored throughout the stone's rotation
https://www.jamesallen.com/loose-di...f-color-vs2-clarity-excellent-cut-sku-4977768

If you can get IS for these, great, but both are pretty safe in angles. I personally prefer 4956910.
https://www.jamesallen.com/loose-di...-color-vvs2-clarity-excellent-cut-sku-4770942
https://www.jamesallen.com/loose-di...f-color-vs1-clarity-excellent-cut-sku-4956910

I know you wanted high clarity, but I have to post this because it is lovely, eyeclean and larger than any of the above.
https://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-3950139.htm {1.4 G SI1}

Other WF options
https://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-3986335.htm {1.126 F SI1}
https://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-3968194.htm {super-ideal that slightly over the budget, but gorgeous}
https://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-3970286.htm
 
rockysalamander said:
4977768 has good angles, but it will tend to have less light return upon close examination (i.e. go grey when your head is close). The inclusions are also black and I find them distracting as they are mirrored throughout the stone's rotation
https://www.jamesallen.com/loose-di...f-color-vs2-clarity-excellent-cut-sku-4977768
Click to expand...
Why would this diamond go grey when a person's head is close? A while back, when I was searching for diamond studs, I was surprised and confused to see diamonds I felt had good angles go grey. I didn't buy the diamonds for this very reason but couldn't understand why I was seeing this "greying". Could you further explain the reason for this?
 
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