33 degree crown angle too shallow?

[dveeg]

Looking at a couple of diamonds, should I be concerned with the 33 degree crown angle on this one? Unfortunately I will not be able to get idealscopes of the diamonds

1.10ct
G
VS1
Depth: 59.6, Table: 59, Crown: 33, Pavilion: 40.8
GIA ex, ex, ex
1.1 HCA score

Or is this diamond more promising?
1.09ct
G
VS2 (several twinning wisps)
Depth: 60.2, Table: 58, Crown: 34, Pavilion: 40.6
GIA ex, ex, ex
0.7 HCA score

 

[diamondseeker2006]

Do you have magnified images of the stones? That is better than nothing. I would not consider buying a diamond blind. There are too many sources who will provide an idealscope to buy from one who doesn't. Of course, you can buy an idealscope yourself and learn to use it if you want to go to the trouble of buying the diamond and potentially returning it.

But if I was forced to buy without an idealscope image, I would absolutely stick to 34-35 for the crown angle and 40.6-41.0 for the pavilion angle. GIA rounds their numbers so that crown angle could actually be lower than 33.

 

[dveeg]

Do you have magnified images of the stones? That is better than nothing. I would not consider buying a diamond blind. There are too many sources who will provide an idealscope to buy from one who doesn't. Of course, you can buy an idealscope yourself and learn to use it if you want to go to the trouble of buying the diamond and potentially returning it.

But if I was forced to buy without an idealscope image, I would absolutely stick to 34-35 for the crown angle and 40.6-41.0 for the pavilion angle. GIA rounds their numbers so that crown angle could actually be lower than 33.

Thanks! Do you think several twinning wisps could be a factor? I know making this decision 'blind' isn't great, but unfortunately it is the situation that I'm in

http://www.gia.edu/cs/Satellite?rep...ename=GIA/Dispatcher&c=Page&cid=1355954554547

 

[diamondseeker2006]

Usually twining wisps are okay, but it does say additional twining wisps not shown. There's just no way to know about the light performance of the stone and the effect of the inclusions from the report. I hope since it is VS2 you don't need to worry but I would say you'd have to be at VS1 clarity for clarity to be of no concern at all. If you order without seeing it, can you send it to an independent appraiser and then return it if necessary?

I imagine the first one has a larger diameter than the second one, right?

 

[dveeg]

Usually twining wisps are okay, but it does say additional twining wisps not shown. There's just no way to know about the light performance of the stone and the effect of the inclusions from the report. I hope since it is VS2 you don't need to worry but I would say you'd have to be at VS1 clarity for clarity to be of no concern at all. If you order without seeing it, can you send it to an independent appraiser and then return it if necessary?

I imagine the first one has a larger diameter than the second one, right?

Correct...
The first one (1.10 VS1) has measurements of 6.71 - 6.73 x 4.01 mm. 3.0% (Medium) girdle

...and second one (1.09 VS2 w/ twinning wisps) has measurements of 6.64 - 6.67 x 4.01 mm. 3.5% (Medium-slightly thick) girdle



With the shallow crown on #1, I am concerned that it might not have enough fire

 

[diamondseeker2006]

The first stone is cut more for brightness, which isn't a bad thing. You need to be looking at crown angles in the 34.8-35 range if you want more fire. But trust me, you are likely in lighting environments more often that favor brightness over fire. I have a stone with a high crown and rarely do I see fire. However, either of these two stones could have leakage and one be superior to the other.

Are you limited to these two stones only?

 

[dveeg]

Good point on the brightness vs fire, I appreciate the explanation. I am limited to a choice between these two stones, so I am trying to make the best of the situation. I know she will be happy with either, but I'm just trying to make the most informed decision I can with the amount of information that is available to me....your insight has been very helpful.

 

[dveeg]

After going through lots of different options and examples with my girlfriend, she definitely prefers brilliance and sparkle over fire. Do PS'ers think this would potentially fit that?

 

[dearbornpop]

Hello! I'm considering a diamond with the similar specs. Were you happy with your selection?
Measurements 6.98 – 7.02 x 4.22 mm
Carat Weight 1.28 carat
Color Grade G
Clarity Grade VS1
GIA 3 Excellent

PROPORTIONS:
Depth 60.3 %
Table 59 %
Crown Angle 33°
Crown Height 13.5%
Pavilion Angle 40.8°
Pavilion Depth 43 %
Star Length 45%
Lower Half 80%
Girdle Medium, Faceted, 4.0%
Culet None

 

[Karl_K]

The original poster hasn't been on PS in 2 years.

The problem is GIA rounding making it impossible to know what the real angles are.
In general for a 60/60 style stone an actual 33 crown and a 40.8 pavilion is a good combination.
Like most 60/60 it tends towards the brightness side.
That does not mean it will not have great fire in the right lighting.

 

[WinkHPD]

The original poster hasn't been on PS in 2 years.

The problem is GIA rounding making it impossible to know what the real angles are.
In general for a 60/60 style stone an actual 33 crown and a 40.8 pavilion is a good combination.
Like most 60/60 it tends towards the brightness side.
That does not mean it will not have great fire in the right lighting.

And I will venture that if you put such a diamond side by side with a true super ideal cut diamond that the visual difference would leave you wanting the super ideal in well over 90% of the time. YOU CAN SEE THE DIFFERENCE!

Wink

 

[Karl_K]

The original poster hasn't been on PS in 2 years.

The problem is GIA rounding making it impossible to know what the real angles are.
In general for a 60/60 style stone an actual 33 crown and a 40.8 pavilion is a good combination.
Like most 60/60 it tends towards the brightness side.
That does not mean it will not have great fire in the right lighting.

And I will venture that if you put such a diamond side by side with a true super ideal cut diamond that the visual difference would leave you wanting the super ideal in well over 90% of the time. YOU CAN SEE THE DIFFERENCE!

Wink

Sure many people can see the difference.
The personality of the diamonds would be different.
That does not make a well cut 60/60 a bad diamond.
I don't think it would be anywhere near as cut and dried as 90%.

That does not mean that every 60/60 diamond is going to be well cut.
There are some really badly cut ones out there.
Compare them to a well cut ideal-cut and then it would be more like 90%

 

[dearbornpop]

Thanks! The stone was graded by GIA as a triple-X does that carry any weight?

 

[Karl_K]

Thanks! The stone was graded by GIA as a triple-X does that carry any weight?

very little but some.
The GIA EX cut grade is considered overly generous and the numbers used are rounded averaged then grossly rounded.
However depending on the specifics within the GIA rounding and averaging there is a potential for AGS AGS0 a much stricter standard.

 

[gm89uk]

The original poster hasn't been on PS in 2 years.

The problem is GIA rounding making it impossible to know what the real angles are.
In general for a 60/60 style stone an actual 33 crown and a 40.8 pavilion is a good combination.
Like most 60/60 it tends towards the brightness side.
That does not mean it will not have great fire in the right lighting.

And I will venture that if you put such a diamond side by side with a true super ideal cut diamond that the visual difference would leave you wanting the super ideal in well over 90% of the time. YOU CAN SEE THE DIFFERENCE!

Wink

Would you think this is also true, for an extremely well cut with lovely ASET with a 36/40.6 combo instead of the traditional range for super ideals? I always wonder why 35.5/40.6 are not included in super ideal range..

 

[dearbornpop]

Here is another 60/60 diamond. Can you tell me what's wrong with it? It looks perfect to the untrained eye!

http://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-3712437.htm

 

[bmfang]

Here is another 60/60 diamond. Can you tell me what's wrong with it? It looks perfect to the untrained eye!

http://www.whiteflash.com/loose-diamonds/round-cut-loose-diamond-3712437.htm

I do hope you have realised that the photo on that listing is of a sample diamond image only and does not actually represent the diamond that is listed.

The report for that one looks like a shallow crown coupled with an pavillion that would be within the super-ideal range (so potentially cut for brightness over fire). And it's close to a 60/60. Not my ideal type of diamond, but hey, it takes all kinds to be diamond lovers out there in the world...

 

[Karl_K]

always wonder why 35.5/40.6 are not included in super ideal range..

with a 55% table or smaller and the right minors they can get ags0.
With excellent optical symmetry there is no reason they cant be classified as super-ideals.
Keep in mind there is no standardized criteria for super-ideal.

 

[gm89uk]

always wonder why 35.5/40.6 are not included in super ideal range..

with a 55% table or smaller and the right minors they can get ags0.
With excellent optical symmetry there is no reason they cant be classified as super-ideals.
Keep in mind there is no standardized criteria for super-ideal.

Thanks Karl. You don't think >55 tables with higher crowns are capable of AGS0 (if well cut)? Looking at the AGS charts, a perfectly symmetrical 60 table 36/40.7 seems to be theoretically capable of AGS 0.

I assume by right minors you mean slightly longer LGF% so that there isn't too much over contrast.. I understand what you're saying but across the market; white flash, HPD, Brian gavin, GOG, VC, I've never seen a super ideal with a 35.5 crown (always down graded to expert selection / platinum or whatever is next in line). I know as member of trade you cannot comment on any of those specifically but in general, the super ideal configuration is 34 to 35, 40.6 to <41. As you've confirmed with your previous post there's no reason for a well cut 35.5/40.6 (with a smaller table which is new information for me) to be optically inferior to the traditional quoted range so why do you think this range is excluded? Is it a marketing decision that closer to tolk proportions are likely to be seen as better or a legitimate optical difference?

 

[Karl_K]

always wonder why 35.5/40.6 are not included in super ideal range..

with a 55% table or smaller and the right minors they can get ags0.
With excellent optical symmetry there is no reason they cant be classified as super-ideals.
Keep in mind there is no standardized criteria for super-ideal.

Thanks Karl. You don't think >55 tables with higher crowns are capable of AGS0 (if well cut)? Looking at the AGS charts, a perfectly symmetrical 60 table 36/40.7 seems to be theoretically capable of AGS 0.

I assume by right minors you mean slightly longer LGF% so that there isn't too much over contrast.. I understand what you're saying but across the market; white flash, HPD, Brian gavin, GOG, VC, I've never seen a super ideal with a 35.5 crown (always down graded to expert selection / platinum or whatever is next in line). I know as member of trade you cannot comment on any of those specifically but in general, the super ideal configuration is 34 to 35, 40.6 to <41. As you've confirmed with your previous post there's no reason for a well cut 35.5/40.6 (with a smaller table which is new information for me) to be optically inferior to the traditional quoted range so why do you think this range is excluded? Is it a marketing decision that closer to tolk proportions are likely to be seen as better or a legitimate optical difference?

I am guessing the biggest reason there are not many of them is weight retention and money.
If they are cutting a 35.5 crown they are going to cut the deepest pavilion that will get gia ex. that the rough supports.
The ones intentionally cutting/marketing super-ideals target different proportions.

They do look different than say 34.8/40.8/55t combination but in my opinion they still look as awesome when well cut.
Its like which is better a sausage and bacon pizza or a sausage and mushroom pizza? Both great just different :}

 

[gm89uk]

I am guessing the biggest reason there are not many of them is weight retention and money.
If they are cutting a 35.5 crown they are going to cut the deepest pavilion that will get gia ex. that the rough supports.
The ones intentionally cutting/marketing super-ideals target different proportions.

They do look different than say 34.8/40.8/55t combination but in my opinion they still look as awesome when well cut.
Its like which is better a sausage and bacon pizza or a sausage and mushroom pizza? Both great just different :}

that settles what I'm having for lunch! I've seen some lovely stones in virtual inventory with such proportions. WF for example explicitly state they won't cut greater than 35. I'm just wondering why the ones intentionally cutting for superideal don't consider this proportion? Surely i there are circumstances although rare, where cutting to 35.5 / 40.6 would lead to more weight retention (than 34/41) and still something that could be classified and priced at their top premium. I feel this must be true because there are quite a few virtual inventory 35.5 to 36/40.6. This standard set by super ideal vendors have led to many customers automatically disqualifying such stones from their search as they try to acquire top quality cut without a pricetag. This is a logic I can follow, but what I can't understand is why the superideal vendors have made the marketing decision to not include the higher crowned stones in their top of the line cut (I'm sure many people here would love the emphasis on fire) especially if it's backed up as the finest cut.

Is it because those diamonds look too different from a 34/40.9 diamond that there would be inconsistency in the appearance of a brand? Even then, is that really a reason as there is already reasonable variation between 57/34/40.9 and 54/35/40.6.

It would be great if some of the vendors could chime in. Maybe this would be better as a separate topic, sorry for the hijack diveeg. It was just the comments by Wink here that instigated my thought process.

 

[Karl_K]

There are a lot of different things that go into deciding what to cut or have cut and put under your brand.
Rough availability
affordability/yield
suitability for production
demand
marketing
preference of the brand creator/designer.

Yoram or Paul would likely say that isn't a 1/10th of the considerations.

One thing to consider is how wide a range do you have to chase inclusions or other issues.
For example if you target 40.9/34.9/56t and run into issues you can cut down to 40.6/34 and get a readily salable super-ideal.
You have a large range of lowers 74 to 80+ to work with.
You also have some tolerance for slight digging and painting with out affecting performance.
If you target 40.6/35.5 and run into an issue if you go under 40.5.
On the crown you can run it down to 34 but you lose a lot of weight.
You lower range becomes 77-80+ to keep in the sweet spot.

It gets complicated in a hurry.

 

[Dancing Fire]

Is it because those diamonds look too different from a 34/40.9 diamond that there would be inconsistency in the appearance of a brand? Even then, is that really a reason as there is already reasonable variation between 57/34/40.9 and 54/35/40.6.

Would love to own a well cut diamond with these specs...

 

[pyramid]

Maybe I am wrong or misinterpreted this and Karl K would definitely know. I seem to remember reading years ago from either Brian Gavin or perhaps Garry Holloway. I think it was Brian. That with a 40.6 pavilion if you went over 35 degrees on the crown that you would be bothered with head shadow. I remember Whiteflash when under Brian Gavin having some 40.5 degrees pavilion angles but don't know if they came from their 'cherished' range which was the equivalent of 'expert collection' rather than 'A Cut Above'.

 

[Karl_K]

Maybe I am wrong or misinterpreted this and Karl K would definitely know. I seem to remember reading years ago from either Brian Gavin or perhaps Garry Holloway. I think it was Brian. That with a 40.6 pavilion if you went over 35 degrees on the crown that you would be bothered with head shadow. I remember Whiteflash when under Brian Gavin having some 40.5 degrees pavilion angles but don't know if they came from their 'cherished' range which was the equivalent of 'expert collection' rather than 'A Cut Above'.

You can go down to 40.5 actual angles on all mains under carefully controlled cutting but it falls off a cliff much below that(aprox. 40.45).
It was Paul that had some that went down to the 40.5 range as I remember. There are not many cutters that can pull it off and make them awesome.
In general and especially with gia numbers 40.6 is my bottom limit.
There are some other ways to break that rule for example 40.2/38/50t with 85% lowers is a combo I would love to see but again that is a whole new ball game.