Crown Height in Cushions...A Discussion

[Lorelei]

As an ongoing discussion from this thread - https://www.pricescope.com/community/threads/cushion-cut-stats-what-do-you-think.136266/ chunkycushionlover as questioned the usefulness of knowing the crown height measurements in cushion cuts.

This is a valid and interesting question and one worth discussing! I personally believe that crown heights in cushions and other fancy shapes are useful to know as PART of the overall picture along with images such as ASET, videos and detailed photographs and so forth. Knowing the crown height won't guarantee the beauty/optics/performance/ fire of any diamond but I think it is a useful value to know. With vendors that provide cushions and other fancy shapes of good cut quality or are cut for optical performance the CH is almost always mentioned and available for the buyer, so it would be interesting to hear from these experts how they feel about the validity of knowing the crown height, not only for them but how useful they feel it is for the cushion/ fancy shape buyer to know.

The question is; is it worth pursuing the crown height and asking a vendor to get this measurement if it isn't already provided or is it not really necessary? The Sarin or Helium scan itself provides other detailed measurements which is really of little to no value to the layperson and even some enthusiasts ( in my opinion) however it seems over a long period of time that the crown height which appears on these scans has been useful to buyers and hobbyists.

Bear in mind that no images or amount of information can truly tell any buyer whether they are going to love a diamond or not or whether a particular stone is going to be suitable without comparing and viewing in person, or that a particular diamond is definitely going to behave in a certain way.

Please discuss!

 

[Karl_K]

With step cuts it is absolutely critical.
The reason being is that the higher the crown for any given table the more and smaller VF''s are created and it increases off axis light draw and fire.
It also tends to throw the virtual facets out of phase which increases contrast.
Phase contrast is another form of contrast that reflector images do not show.
In other words the virtual facets may all show up red in the ASET but they are on and off at different times(out of phase) in the real world.

Flat tops can and do look dead because of ineffective large virtual facets and in phase virtual facets.

With cushions(and RB''s) it works somewhat the same way but not to the extreme it does with step cuts. (large tables favor brightness over fire)
Also flat top cushions are not cut often but they are out there.
Since the crown height is proportional to the crown angle and the table size in cushions and RB''s it is also less vital to know it if you know the others.
However with step cuts it is not proportional to angle and table size as the steps can be different heights.
This image will show it with asscher pavilions, the same applies to the crown.
These 2 will have the exact same sarin numbers all across the board but the pavilion facets are in different places.

 

[Karl_K]

continued:

With step cuts I would put the crown height as 100% need to know with cushions I would put it as nice to know in most cases.

 

[Karl_K]

part 3:
Just read the other thread:
Any time the numbers are out of the norm for a cut the more I would want the crown height and other numbers.
The shallower cushion I would 100% want the crown height.
With the other it would just be nice to know just to make sure it isn''t cut weird.
A good side photo will tell the same thing.

 

[Lorelei]

Date: 2/13/2010 11:37:48 AM
Author: Karl_K
part 3:
Just read the other thread:
Any time the numbers are out of the norm for a cut the more I would want the crown height and other numbers.
The shallower cushion I would 100% want the crown height.
With the other it would just be nice to know just to make sure it isn''t cut weird.
A good side photo will tell the same thing.

Thanks for your input Karl!

 

[diagem]

Date: 2/13/2010 11:54:10 AM
Author: Lorelei

Date: 2/13/2010 11:37:48 AM
Author: Karl_K
part 3:
Just read the other thread:
Any time the numbers are out of the norm for a cut the more I would want the crown height and other numbers.
The shallower cushion I would 100% want the crown height.
With the other it would just be nice to know just to make sure it isn''t cut weird.
A good side photo will tell the same thing.

Thanks for your input Karl!

And with a deep cushion too..., 100%,
Flat top cushions are a majority in the cushion jungle.

 

[Rhino]

I have two thoughts about this subject.

Firstly, while the crown height of a cushion will not necessarily dictate it''s facet structure a tall crown was generally found on the older styled cuts (old mine) typically referred to as the vintage or chunky facet style. There are however chunky faceted cushions with flat crowns too and I''ve also encountered modern faceted cushions with tall crowns as well. Crown height is certainly helpful to know and particularly of value if a consumer enjoys a nice height to the profile of their diamond.

As Karl pointed out it is vital to step cuts and Diagem to cushions although most cushions do not have crowns taller than say 10-14%. Some of the best cuts on the market do indeed have tall crowns of which I''d throw princess cuts into the mix as well. The nicest princess cuts we''ve enountered have had nice tall crowns.

At the same time I would also stress that while knowing the crown height is good information to have, it is not conclusive information if one is seeking to ascertain answers to beauty and overall optical performance. I''ve seen cushions, asschers and princess with tall crowns that have been optically disastrous. For a complete evaluation one must not only have pavilion information but must be intimately familiar with how those pavilion angles/depth work with the given crown height. This is where optical testing is crtical and key as it provides the missing keys if one is familiar with how those optical tests correlate to practical observation.

Knowing crown height alone without seeing how it works in synergy with the pavilion angles, lower half angles and lower half length is moot information and incomplete for the overall picture.

This is what I believe you are communicating too Lorelei.

All the best,

 

[Rhino]

Also on topic ...

On a personal level I LOVE tall crowns. I love a bold profile even though a taller crown deducts from the overall spread of a diamond. People sometimes tend to stress "face up" or "spread" but when you have the proper chemistry between a tall crown coupled with the proper pavilion that *works* with that crown ... I''ll sacrifice a tad of spread for the bold look you attain in the height you will over a flat crown.

I just mounted up an AV OEC for myself around a carat and a half and the dispersion that just comes out of this tall crown is like ...

 

[Lorelei]

Date: 2/13/2010 4:58:01 PM
Author: Rhino
I have two thoughts about this subject.

Firstly, while the crown height of a cushion will not necessarily dictate it''s facet structure a tall crown was generally found on the older styled cuts (old mine) typically referred to as the vintage or chunky facet style. There are however chunky faceted cushions with flat crowns too and I''ve also encountered modern faceted cushions with tall crowns as well. Crown height is certainly helpful to know and particularly of value if a consumer enjoys a nice height to the profile of their diamond.

As Karl pointed out it is vital to step cuts and Diagem to cushions although most cushions do not have crowns taller than say 10-14%. Some of the best cuts on the market do indeed have tall crowns of which I''d throw princess cuts into the mix as well. The nicest princess cuts we''ve enountered have had nice tall crowns.

At the same time I would also stress that while knowing the crown height is good information to have, it is not conclusive information if one is seeking to ascertain answers to beauty and overall optical performance. I''ve seen cushions, asschers and princess with tall crowns that have been optically disastrous. For a complete evaluation one must not only have pavilion information but must be intimately familiar with how those pavilion angles/depth work with the given crown height. This is where optical testing is crtical and key as it provides the missing keys if one is familiar with how those optical tests correlate to practical observation.

Knowing crown height alone without seeing how it works in synergy with the pavilion angles, lower half angles and lower half length is moot information and incomplete for the overall picture.

This is what I believe you are communicating too Lorelei.

All the best,

It is indeed Jon, thank you and thanks for the thoughts and advice!

 

[Lorelei]

Date: 2/13/2010 5:05:43 PM
Author: Rhino
Also on topic ...

On a personal level I LOVE tall crowns. I love a bold profile even though a taller crown deducts from the overall spread of a diamond. People sometimes tend to stress ''face up'' or ''spread'' but when you have the proper chemistry between a tall crown coupled with the proper pavilion that *works* with that crown ... I''ll sacrifice a tad of spread for the bold look you attain in the height you will over a flat crown.

I just mounted up an AV OEC for myself around a carat and a half and the dispersion that just comes out of this tall crown is like ...

I can''t wait to see THIS!!!!!

 

[Rhino]

haha... you''ll see a clip before I leave today.

 

[Lorelei]

Date: 2/13/2010 5:15:23 PM
Author: Rhino
haha... you''ll see a clip before I leave today.

 

[ChunkyCushionLover]

Lorelei,

I think the way you presented this thread gave much too wide latitude in the responses. So I'd like to put it in more simple and focussed terms:

How does knowing the crown height % for a cushion help in overall asessment of a single particular cushion a consumer is considering for selection or rejection purposes?
How does knowing that single piece of information help routinely in threads where customers are asking for opinions on a their potential purchase?

i) with ASETm available
ii) without an ASET available

------------------------------------------------------------------------------------------------------------------------------------------------------------------------

1) I hope we are all in agreement that judging a cushion by the numbers and without images is a difficult task.

2) We do not have the average crown and pavillion angles, LGF%, UGF, Star% , Girdle %, Pavillion Depth % etc etc or often even the proper pavillion facet structure (number of mains)! As I mentioned in the previous thread with a full sarin scan and DiamCalc one could generate images for the stone and evaluate potential light performance, otherwise we are still no closer to a definitive conclusion on optics with Crown Height than we were before.

3) For those of you like Karl who said that knowing the crown height of a 60% depth shallow cushion was important please explain what it helps you evaluate for a single potential choice (not on an academic level)? You want to know if the crown is flat top, moderate or a steep crown but please do take it further, otherwise you are giving your opinion with absolutely no application. Please point me to a thread or provide images where this information was used as a determining factor?

Consider the three following potential proportions for this 60% depth cushion please see the other thread for the other information:

Case I (Flat Crown, Moderate Pavillion)
(Crown 8%, Girdle 4%, Pavillion 48%)

Case II (Moderate Crown, Shallow Pavillion)
(Crown 12 - 18%, Girdle 4%, Pavillion 39 - 44%)

This is more likely the case for this cushion given the 57% table

Case II (Tall Crown, Very Shallow Pavillion)
(Crown 21% Girldle 4%, Pavillion 35%) (Crown Angle ~41 Degrees)

I don't see why putting the stone in either of the three cases will help in evaluation of this cushion, its likely all three scenarios are

but case II is the most promising but that is still way too little information to draw any conclusion.

 

[ChunkyCushionLover]

Date: 2/13/2010 11:26:47 AM
Author: Karl_K
With step cuts it is absolutely critical.
The reason being is that the higher the crown for any given table the more and smaller VF''s are created and it increases off axis light draw and fire.
It also tends to throw the virtual facets out of phase which increases contrast.
Phase contrast is another form of contrast that reflector images do not show.
In other words the virtual facets may all show up red in the ASET but they are on and off at different times(out of phase) in the real world.

Flat tops can and do look dead because of ineffective large virtual facets and in phase virtual facets.

With cushions(and RB''s) it works somewhat the same way but not to the extreme it does with step cuts. (large tables favor brightness over fire)
Also flat top cushions are not cut often but they are out there.
Since the crown height is proportional to the crown angle and the table size in cushions and RB''s it is also less vital to know it if you know the others.
However with step cuts it is not proportional to angle and table size as the steps can be different heights.
This image will show it with asscher pavilions, the same applies to the crown.
These 2 will have the exact same sarin numbers all across the board but the pavilion facets are in different places.

Karl,

My point with Lorelei is restricted to Cushions, the point is well taken that with Large VFs (often found in step cuts) a static ASET image cannot accurately distinguish between areas of obstruction over a wide range of angles or ones where the slightest tilt causes intense light return(ASET RED) rather than obstruction(ASET BLUE). I remember Serg''s example of the Carre diamond ASET as a particularly extreme example. As you have mentioned either implicitly or explicitly in many threads you have difficulty using an ASET as a selection tool for Asschers although it is routinely used as a rejection tool by you and others.

CCL

 

[Lorelei]

Date: 2/14/2010 12:50:01 PM
Author: ChunkyCushionLover
Lorelei,

I think the way you presented this thread gave much too wide latitude in the responses. So I'd like to put it in more simple and focussed terms:

How does knowing the crown height % for a cushion help in overall asessment of a single particular cushion a consumer is considering for selection or rejection purposes?
How does knowing that single piece of information help routinely in threads where customers are asking for opinions on a their potential purchase?

i) with ASETm available
ii) without an ASET available

------------------------------------------------------------------------------------------------------------------------------------------------------------------------

1) I hope we are all in agreement that judging a cushion by the numbers and without images is a difficult task.

2) We do not have the average crown and pavillion angles, LGF%, UGF, Star% , Girdle %, Pavillion Depth % etc etc or often even the proper pavillion facet structure (number of mains)! As I mentioned in the previous thread with a full sarin scan and DiamCalc one could generate images for the stone and evaluate potential light performance, otherwise we are still no closer to a definitive conclusion on optics with Crown Height than we were before.

3) For those of you like Karl who said that knowing the crown height of a 60% depth shallow cushion was important please explain what it helps you evaluate for a single potential choice (not on an academic level)? You want to know if the crown is flat top, moderate or a steep crown but please do take it further, otherwise you are giving your opinion with absolutely no application. Please point me to a thread or provide images where this information was used as a determining factor?

Consider the three following potential proportions for this 60% depth cushion please see the other thread for the other information:

Case I (Flat Crown, Moderate Pavillion)
(Crown 8%, Girdle 4%, Pavillion 48%)

Case II (Moderate Crown, Shallow Pavillion)
(Crown 12 - 18%, Girdle 4%, Pavillion 39 - 44%)

This is more likely the case for this cushion given the 57% table

Case II (Tall Crown, Very Shallow Pavillion)
(Crown 21% Girldle 4%, Pavillion 35%) (Crown Angle ~41 Degrees)

I don't see why putting the stone in either of the three cases will help in evaluation of this cushion, its likely all three scenarios are

but case II is the most promising but that is still way too little information to draw any conclusion.

CCL,

I will leave the CH query concerning the flatter top cushions to Karl and the other experts to give specific examples.

Also I will try to explain again, although I am probably for some reason not getting this across very well...But I think for the most part we are in agreement.
The CH is only part of the story and not something to be used for rejection or selection purposes on any basis - or should not be, nor does it give any real information on optics. CH is not something that will make or break a diamond but it is as Jon says good to know and also of value from an aesthetic point of view for those who like a high profile on their stone, it is however possible however an image would give similar information but unless you are famliiar with estimating CH from an image then that wouldn't help much. Also images have real limitations. For online buyers their best asset is their vendor's eyes and expertise to describe the characteristics of a diamond until they can see the diamond for themselves and compare it with others. Images themselves are not enough I believe to guarantee that a diamond is going to appeal to the buyer/ wearer, nor do they show the personality or the performance nuances of any diamond, videos can help there somewhat but in the end it has to come down to the viewer's own tastes and ideals of beauty - and images can't account for that, they can only take us so far but they can't really depict with any accuracy any aspect of performance. Neither can the CH and thats my point, you can have badly cut stones with a high CH and great looking diamonds with a shallow CH- its not a major determining factor for beauty or performance but I feel its useful to have as a part of the overall picture.

Also as a diamond buyer myself, if the CH measurement is available ( were I fortunate enough to be buying a cushion!!) then I would want that information. For Pricescope purposes, we all work in different ways, CH is something I like to have, it is something you don't feel you need - thats fine, I can request it until I do or do not decide otherwise, you can work without it so don't feel you need it. This is a forum where different opinions abound, advisory techniques etc - as long as these are respected thats great and these types of discussions can help everyone especially as when it comes down to it, for the most part we are still just consumers that lack real experience and expertise.

So to sum up, personally think the info is useful along with images and the other proportions used to evaluate a cushion unless it is proven otherwise to my satisfaction. I will as always keep an open mind but for the time being I will continue as usual to request this info where possible if it isn't already provided, and in many cases it is anyway.

 

[Karl_K]

Date: 2/14/2010 1:00:05 PM
Author: ChunkyCushionLover

My point with Lorelei is restricted to Cushions, the point is well taken that with Large VFs (often found in step cuts) a static ASET image cannot accurately distinguish between areas of obstruction over a wide range of angles or ones where the slightest tilt causes intense light return(ASET RED) rather than obstruction(ASET BLUE). I remember Serg's example of the Carre diamond ASET as a particularly extreme example. As you have mentioned either implicitly or explicitly in many threads you have difficulty using an ASET as a selection tool for Asschers although it is routinely used as a rejection tool by you and others.


CCL

This applies to any cut not just step cuts.
It is very relevant to cushion cuts.

ASET overstates and understates contrast at the same time, tells you nothing about off axis light draw, nothing directly about scintillation (some can be inferred somewhat but can give a false picture), and next to nothing about fire.

example:
if you believe ASET this diamond has almost 0 contrast under the table other than a leaky culet.

 

[Karl_K]

real world has a lot of contrast potential even in flat lighting(which this isn't but it shows out of phase VF's) because the VF's are out of phase.
High crowns enhance this type of contrast.
It is close to impossible for flat tops to have out of phase virtual facets.
Further check out the vid:

http://goodoldgold.com/diamond/6215/

 

[Karl_K]

same thing with an oec/AVR

 

[Karl_K]

near tolk RB''s have built in obstruction contrast on the pavilion mains it is part of the design.
Fancies don''t and the other forms of contrast can play a very important role in their looks and performance.

 

[ChunkyCushionLover]

Date: 2/14/2010 2:27:26 PM
Author: Karl_K
real world has a lot of contrast potential even in flat lighting(which this isn''t but it shows out of phase VF''s) because the VF''s are out of phase.
High crowns enhance this type of contrast.
It is close to impossible for flat tops to have out of phase virtual facets.
Further check out the vid:

http://goodoldgold.com/diamond/6215/

Karl,

Since you brought up the AVC and and in phase out of phase in Old Mine Cushions.

Do you think this stone below then will have real world contrast potential and finding out its crown height is going to help you reccomend it?
I will tell you it has a crown height of 24% and a total depth of 69%. So then what will you say about it?

 

[Karl_K]

Date: 2/17/2010 9:09:29 AM
Author: ChunkyCushionLover

Date: 2/14/2010 2:27:26 PM

Author: Karl_K

real world has a lot of contrast potential even in flat lighting(which this isn''t but it shows out of phase VF''s) because the VF''s are out of phase.

High crowns enhance this type of contrast.

It is close to impossible for flat tops to have out of phase virtual facets.

Further check out the vid:


http://goodoldgold.com/diamond/6215/

Karl,


Since you brought up the AVC and and in phase out of phase in Old Mine Cushions.


Do you think this stone below then will have real world contrast potential and finding out its crown height is going to help you reccomend it?

I will tell you it has a crown height of 24% and a total depth of 69%. So then what will you say about it?

I would say photo not clear enough for decision and ask for an IS/ASET.
Can''t tell if the pavilion is right, there looks to be a large leakage zone but it might just be the lighting.

 

[ChunkyCushionLover]

Date: 2/17/2010 10:46:28 AM
Author: Karl_K

Date: 2/17/2010 9:09:29 AM
Author: ChunkyCushionLover

Date: 2/14/2010 2:27:26 PM

Author: Karl_K

real world has a lot of contrast potential even in flat lighting(which this isn't but it shows out of phase VF's) because the VF's are out of phase.

High crowns enhance this type of contrast.

It is close to impossible for flat tops to have out of phase virtual facets.

Further check out the vid:


http://goodoldgold.com/diamond/6215/

Karl,


Since you brought up the AVC and and in phase out of phase in Old Mine Cushions.


Do you think this stone below then will have real world contrast potential and finding out its crown height is going to help you reccomend it?

I will tell you it has a crown height of 24% and a total depth of 69%. So then what will you say about it?

I would say photo not clear enough for decision and ask for an IS/ASET.
Can't tell if the pavilion is right, there looks to be a large leakage zone but it might just be the lighting.

I chose this diamond to illustrate two points as it has particularly poor light return under the table http://www.goodoldgold.com/diamond/6909/

1) I don't feel you can judge anything precisely about the relative phases of the mains from the height of the crown, this stone has a 2% too deep crown and 2% too shallow pavillion over an AVC and the optics are changed dramatically.
2) Normal pictures are equally inconclusive.

Are you legitimately worried about an 8 main antique cushion looking like a headlight(6215 ASET) under the table with no contrast because you see predominantly red with only a slight bit of leakage and green in the ASET?

 

[diagem]

Date: 2/17/2010 9:09:29 AM
Author: ChunkyCushionLover

Date: 2/14/2010 2:27:26 PM

Author: Karl_K

real world has a lot of contrast potential even in flat lighting(which this isn''t but it shows out of phase VF''s) because the VF''s are out of phase.

High crowns enhance this type of contrast.

It is close to impossible for flat tops to have out of phase virtual facets.

Further check out the vid:


http://goodoldgold.com/diamond/6215/

Karl,


Since you brought up the AVC and and in phase out of phase in Old Mine Cushions.


Do you think this stone below then will have real world contrast potential and finding out its crown height is going to help you reccomend it?
I will tell you it has a crown height of 24% and a total depth of 69%. So then what will you say about it?

I would say it is probably a gorgeous Diamond. With a shallower CH, the overall appearance would look different.

 

[Karl_K]

Date: 2/17/2010 11:41:14 AM
Author: ChunkyCushionLover

I chose this diamond to illustrate two points as it has particularly poor light return under the table http://www.goodoldgold.com/diamond/6909/


1) I don''t feel you can judge anything precisely about the relative phases of the mains from the height of the crown, this stone has a 2% too deep crown and 2% too shallow pavillion over an AVC and the optics are changed dramatically.

The crown is fine the pavilion just doesn''t match it well.
No matter what the pavilion has to compliment the crown that is first and foremost.

 

[diagem]

Date: 2/17/2010 12:59:31 PM
Author: Karl_K

Date: 2/17/2010 11:41:14 AM
Author: ChunkyCushionLover

I chose this diamond to illustrate two points as it has particularly poor light return under the table http://www.goodoldgold.com/diamond/6909/


1) I don''t feel you can judge anything precisely about the relative phases of the mains from the height of the crown, this stone has a 2% too deep crown and 2% too shallow pavillion over an AVC and the optics are changed dramatically.

The crown is fine the pavilion just doesn''t match it well......enough to reflect back light unobstructed..., but it does seem like a great Cushion to me.
No matter what the pavilion has to compliment the crown that is first and foremost.

Sorry to slip in...

And I dont mean anything negatively about it..., but one of the effects of shallow CH & CA on a Cushion is:

https://www.pricescope.com/community/threads/new-cushion-opinions-please.136606/

It still can look amazing (this Cushion does look promising), but different from high CH Cushions...

 

[ChunkyCushionLover]

Date: 2/17/2010 5:10:45 PM
Author: DiaGem

Date: 2/17/2010 12:59:31 PM
Author: Karl_K

Date: 2/17/2010 11:41:14 AM
Author: ChunkyCushionLover

I chose this diamond to illustrate two points as it has particularly poor light return under the table http://www.goodoldgold.com/diamond/6909/


1) I don't feel you can judge anything precisely about the relative phases of the mains from the height of the crown, this stone has a 2% too deep crown and 2% too shallow pavillion over an AVC and the optics are changed dramatically.

The crown is fine the pavilion just doesn't match it well......enough to reflect back light unobstructed..., but it does seem like a great Cushion to me.
No matter what the pavilion has to compliment the crown that is first and foremost.

Sorry to slip in...

And I dont mean anything negatively about it..., but one of the effects of shallow CH & CA on a Cushion is:

https://www.pricescope.com/community/threads/new-cushion-opinions-please.136606/

It still can look amazing (this Cushion does look promising), but different from high CH Cushions...

Lorelei you going to ask for Bluenile to do a sarin in this customer's thread?

I do find it interesting that Diagem has already inferred from the photo, table % and a depth % (without the crown height or angle) that this is a shallow crown and angle, proving my point. We do not need the CH for this stone, the large table, shallow overall depth, and the photograph are enough to infer this information.

Yet when Lorelei started this thread many of you said it was important to know the CH on a 60% depth cushion!

Do we really care that the precise CH for this stone is about 12% - 18%? I don't think so considering 8 main antiques like GOGs AVC have crown heights in the 19 - 23% range. It certainly won't change my mind about this stone, there are much finer examples of this style stone out there with smaller tables and taller crowns.

I've seen much better antique cushions in the 8 main thick cuttiing style, this one has leakage and a pretty big bowtie which isn't going away with a little tilt. Customer got a lower price on it due to Strong Blue Fluoro and several other factors.

 

[Karl_K]

ccl
Every expert who answered in this thread has said that getting the CH was a good thing.
That is the bottom line.

I have explained why.

That something else might not be right so dismiss it before getting the CH is fine.

The main reason to get the Ch on that one is that the numbers are out of the usual range for the cut.
So it is needed to make sure it is not a flat top.

 

[Lorelei]

Date: 2/17/2010 6:39:46 PM
Author: ChunkyCushionLover

Lorelei you going to ask for Bluenile to do a sarin in this customer's thread?

I do find it interesting that Diagem has already inferred from the photo, table % and a depth % (without the crown height or angle) that this is a shallow crown and angle, proving my point. We do not need the CH for this stone, the large table, shallow overall depth, and the photograph are enough to infer this information.

Yet when Lorelei started this thread many of you said it was important to know the CH on a 60% depth cushion!

Do we really care that the precise CH for this stone is about 12% - 18%? I don't think so considering 8 main antiques like GOGs AVC have crown heights in the 19 - 23% range. It certainly won't change my mind about this stone, there are much finer examples of this style stone out there with smaller tables and taller crowns.

I've seen much better antique cushions in the 8 main thick cuttiing style, this one has leakage and a pretty big bowtie which isn't going away with a little tilt. Customer got a lower price on it due to Strong Blue Fluoro and several other factors.

What I do or do not ask for in threads is my decision at that time CCL and it will remain that way I can assure you. I keep an open mind as always and might change my approach should a certain issue be proven to my satisfaction that I should do so. Until that time the way I post and the info I request is my decision and will be respected as such, same with the threads I choose to respond to. Also DiaGem is an expert and cutter who is skilled in evaluating stones from basic images and proportions, I however and other consumers like myself do not possess such skills and therefore would not evaluate a diamond from a basic photograph etc, therefore I have to respectfully disagree that it proves your point. MY point again is that the CH is useful to know ALONG with the rest of the info available on a diamond but it is not a major determining factor for beauty or optical performance.

 

[diagem]

Date: 2/18/2010 6:36:46 AM
Author: Lorelei

Date: 2/17/2010 6:39:46 PM
Author: ChunkyCushionLover

Lorelei you going to ask for Bluenile to do a sarin in this customer''s thread?

I do find it interesting that Diagem has already inferred from the photo, table % and a depth % (without the crown height or angle) that this is a shallow crown and angle, proving my point. We do not need the CH for this stone, the large table, shallow overall depth, and the photograph are enough to infer this information.

Yet when Lorelei started this thread many of you said it was important to know the CH on a 60% depth cushion!

Do we really care that the precise CH for this stone is about 12% - 18%? I don''t think so considering 8 main antiques like GOGs AVC have crown heights in the 19 - 23% range. It certainly won''t change my mind about this stone, there are much finer examples of this style stone out there with smaller tables and taller crowns.
Sure we care..., or at least we should as there is a HUGE difference within this range as well.
I''ve seen much better antique cushions in the 8 main thick cuttiing style, this one has leakage and a pretty big bowtie which isn''t going away with a little tilt. Customer got a lower price on it due to Strong Blue Fluoro and several other factors.

What I do or do not ask for in threads is my decision at that time CCL and it will remain that way I can assure you. I keep an open mind as always and might change my approach should a certain issue be proven to my satisfaction that I should do so. Until that time the way I post and the info I request is my decision and will be respected as such, same with the threads I choose to respond to. Also DiaGem is an expert and cutter who is skilled in evaluating stones from basic images and proportions, I however and other consumers like myself do not possess such skills and therefore would not evaluate a diamond from a basic photograph etc, therefore I have to respectfully disagree that it proves your point. MY point again is that the CH is useful to know ALONG with the rest of the info available on a diamond but it is not a major determining factor for beauty or optical performance.

Couldnt have said it better

.

 

[Lorelei]

Date: 2/18/2010 8:01:25 AM
Author: DiaGem

Date: 2/18/2010 6:36:46 AM
Author: Lorelei

Date: 2/17/2010 6:39:46 PM

What I do or do not ask for in threads is my decision at that time CCL and it will remain that way I can assure you. I keep an open mind as always and might change my approach should a certain issue be proven to my satisfaction that I should do so. Until that time the way I post and the info I request is my decision and will be respected as such, same with the threads I choose to respond to. Also DiaGem is an expert and cutter who is skilled in evaluating stones from basic images and proportions, I however and other consumers like myself do not possess such skills and therefore would not evaluate a diamond from a basic photograph etc, therefore I have to respectfully disagree that it proves your point. MY point again is that the CH is useful to know ALONG with the rest of the info available on a diamond but it is not a major determining factor for beauty or optical performance.

Couldnt have said it better

.

You are welcome DiaGem. This is an important point, we need to keep the knowledge and expertise of the various participants in this thread in mind so that other posters following this thread understand where the opinions given are coming from.