Return of the Steep/Deep.....

[FB.]

Lots of people love to hate them.

...and there are certainly incentives to cut heavier stones that can nominally attain the highest cut quality.

But I know of some people who dislike the dark 8 black arrows that are visible against the white background in what are considered to be "super-ideal" cuts.
Apart from steep/deep stones (35/41 or higher), how might those people find a stone that doesn't have the dark arrows?

Maybe a small but significant minority in the GIA study saw something they liked about the lack of prominence of the arrows in a steep deep and were prepared to accept a dark ring as a trade off.

I'm beginning to wonder whether, for varieties sake, a true GIA triple Ex, steep/deep is worthy of addition to the collection.
Ring of death? Yes.
Arrows of death? No.

Simulated images attached.

 

[stone-cold11]

Arrow of death is contrast that only turns black at close range viewing for a TIC stone, around 14inches. Ring of death is always present under all viewing condition and makes the stone face up smaller. So choose your poison.

 

[Regular Guy]

Date: 12/1/2009 12:55:41 PM
Author: Stone-cold11
Arrow of death is contrast that only turns black at close range viewing for a TIC stone, around 14inches. Ring of death is always present under all viewing condition and makes the stone face up smaller. So choose your poison.

Stone, my bad...I didn''t read the recent long discussion on this....but I''m guessing you''ve efficiently summarized it here, yes?

 

[stone-cold11]

RG, not really summarized the other thread, this is just my interpretation of the above images and what they meant.

 

[Mrs Mitchell]

I personally dislike the arrows. Took me a long time to admit that, since I get a strong feeling that we''re supposed to love ''em. Sorry, I just don''t.

 

[kenny]

Arrows are more a photography thing than a real life thing.

When I wear my ideal round I almost never notice the arrows, and they are never black.
They only stand out in photography and even then only when the photographer carefully positions the stone, on-axis, into the camera lens.
Next careful lighting can make the arrows stand out.

Yes in certain lighting I can place the stone precisely on axis and find the arrows but 99.99999% of the time in real life they are not visible.

They are only prominent here because we view zillions of well-taken pics of well-cut diamonds here on PS.
The arrows matter because are an indicator of good cut.

I surely hope people who have never seen a well cut diamond think they function like black arrows permanently painted onto the diamond, always present, and always black.

 

[FB.]

Date: 12/1/2009 3:42:02 PM
Author: Mrs Mitchell
I personally dislike the arrows. Took me a long time to admit that, since I get a strong feeling that we''re supposed to love ''em. Sorry, I just don''t.

According to my observations, well-cut stones (GIA triple-Ex) with around 56% table, 33.5 degree crown angle, 41.4 degree pavilion angle and 80% lower half (all these numbers seem tolerant of GIA rounding-off errors) don''t have noticeable arrows, but also don''t noticeably suffer from the steep/deep ring of death.
HCA rates similar stones with a score of 3-4; a mixture of "good" and "very good" for brightness/fire/scintillation/spread. AGA rates them about cut grade 2A.
But I can''t guarantee to be correct, so don''t blame me if I''ve sent you down the wrong track.

 

[Rockdiamond]

Hi all!!

FB, and anyone else looking and interested...... does the simulated diamond on the far right show what is referred to as the "ring of death"?
I have still not seen good photographic evidence of this "Ring of Death" on GIA EX cut grade stones.

The IS image seems to really show something, yet the simulated diamond itself seems to show pleasant contrast rather than some deadly ring.

Mrs Mitchell, I''m totally with you. No only in that I don''t find the arrows in the photos to be attractive, but more so that there''s a strong sentiment on PS that we "should" love what others do. If we don''t like the "Approved PS make", someone is likely to come in and say that it means we like badly cut diamonds.
The truth is that there''s a range of well cut diamonds in GIA''s EX cut grade. There are different makes that many people found attractive during GIA''s extensive human research. Some of which are stones that are knocked here.
The arrows in photos do not even necessarily indicate "good cut" nor does lack of them indicate otherwise.


FB- Yes, there ARE stones deemed to be "Steep Deep" here that certainly ARE not only "drool worth" but also worthy of purchase.
The main aspect to look for to see if a GIA EX cut grade stone is too deep is it''s spread.
If one likes arrows, or does not like arrows, or the supposed "ring of death" as it''s been depicted photographically is only opinion.

 

[Karl_K]

Date: 12/1/2009 3:51:57 PM
Author: FB.

Date: 12/1/2009 3:42:02 PM

Author: Mrs Mitchell

I personally dislike the arrows. Took me a long time to admit that, since I get a strong feeling that we're supposed to love 'em. Sorry, I just don't.

According to my observations, well-cut stones (GIA triple-Ex) with around 56% table, 33.5 degree crown angle, 41.4 degree pavilion angle and 80% lower half (all these numbers seem tolerant of GIA rounding-off errors) don't have noticeable arrows, but also don't noticeably suffer from the steep/deep ring of death.

HCA rates similar stones with a score of 3-4; a mixture of 'good' and 'very good' for brightness/fire/scintillation/spread. AGA rates them about cut grade 2A.

But I can't guarantee to be correct, so don't blame me if I've sent you down the wrong track.

yes a shallow/steep that is with in reason can hide the arrows and not have the darkness over the lower girdles.
AGS hammers such combos for contrast.
That is one of the bugs in the AGS system.
They only recognize obstruction and leakage as contrast.

 

[e5116]

According to my observations, well-cut stones (GIA triple-Ex) with around 56% table, 33.5 degree crown angle, 41.4 degree pavilion angle and 80% lower half (all these numbers seem tolerant of GIA rounding-off errors) don't have noticeable arrows, but also don't noticeably suffer from the steep/deep ring of death.
HCA rates similar stones with a score of 3-4; a mixture of "good" and "very good" for brightness/fire/scintillation/spread. AGA rates them about cut grade 2A.
But I can't guarantee to be correct, so don't blame me if I've sent you down the wrong track.

FB

FB, can you simulate this diamond (56% table, 33.5 crown, 41.4 pavilion) like you did for the ones above? Or perhaps you didn't do the simulation yourself, but rather got the pictures from somewhere else. But I'm curious as to the result. If anybody else could do a similar simulation, it would be greatly appreciated. I actually purchased a diamond with those exact specs (actually 57% table, 60.3% depth, but crown and pav are the same) and it scores a 3.7 on the HCA and a 1B on the AGA scale (GIA gave it an excellent cut grade...). Obviously, this diamond wouldn't be chosen by many on this board, but after comparing it to a diamond that scored a 0.9 on the HCA with a very reputable independent appraiser in a fairly poorly lit gemology lab, that's the one I went with. And the appraiser wholeheartedly agreed. Obviously, different strokes for different folks.

 

[Karl_K]

Here you go...
This combo is very particular about the lgf%.
The muted arrows are apparent in the simulated IS.
33.5 41.4 80lgf% 55% stars

 

[e5116]

Awesome, thanks Karl.

 

[FB.]

Date: 12/1/2009 5:04:10 PM
Author: e5116

According to my observations, well-cut stones (GIA triple-Ex) with around 56% table, 33.5 degree crown angle, 41.4 degree pavilion angle and 80% lower half (all these numbers seem tolerant of GIA rounding-off errors) don''t have noticeable arrows, but also don''t noticeably suffer from the steep/deep ring of death.
HCA rates similar stones with a score of 3-4; a mixture of ''good'' and ''very good'' for brightness/fire/scintillation/spread. AGA rates them about cut grade 2A.
But I can''t guarantee to be correct, so don''t blame me if I''ve sent you down the wrong track.

FB

FB, can you simulate this diamond (56% table, 33.5 crown, 41.4 pavilion) like you did for the ones above? Or perhaps you didn''t do the simulation yourself, but rather got the pictures from somewhere else. But I''m curious as to the result. If anybody else could do a similar simulation, it would be greatly appreciated. I actually purchased a diamond with those exact specs (actually 57% table, 60.3% depth, but crown and pav are the same) and it scores a 3.7 on the HCA and a 1B on the AGA scale (GIA gave it an excellent cut grade...). Obviously, this diamond wouldn''t be chosen by many on this board, but after comparing it to a diamond that scored a 0.9 on the HCA with a very reputable independent appraiser in a fairly poorly lit gemology lab, that''s the one I went with. And the appraiser wholeheartedly agreed. Obviously, different strokes for different folks.

I''ve added 33.5 / 41.4 to the earlier images.

 

[FB.]

Date: 12/1/2009 5:01:11 PM
Author: Karl_K

Date: 12/1/2009 3:51:57 PM
Author: FB.

Date: 12/1/2009 3:42:02 PM

Author: Mrs Mitchell

I personally dislike the arrows. Took me a long time to admit that, since I get a strong feeling that we''re supposed to love ''em. Sorry, I just don''t.

According to my observations, well-cut stones (GIA triple-Ex) with around 56% table, 33.5 degree crown angle, 41.4 degree pavilion angle and 80% lower half (all these numbers seem tolerant of GIA rounding-off errors) don''t have noticeable arrows, but also don''t noticeably suffer from the steep/deep ring of death.

HCA rates similar stones with a score of 3-4; a mixture of ''good'' and ''very good'' for brightness/fire/scintillation/spread. AGA rates them about cut grade 2A.

But I can''t guarantee to be correct, so don''t blame me if I''ve sent you down the wrong track.

yes a shallow/steep that is with in reason can hide the arrows and not have the darkness over the lower girdles.
AGS hammers such combos for contrast.
That is one of the bugs in the AGS system.
They only recognize obstruction and leakage as contrast.

Thanks, Karl.
It''s good to have an expert''s confirmation that my visual observations are roughly correct.

 

[FB.]

David, yes, the "ring of death" is visible just inside the edge of the table on the fourth stone in the simulation.

 

[Rockdiamond]

Thanks FB!

In your opinion, comparing to the other simulated stones, does the "ring of death" look bad to you- or possibly different in such a way others might consider it attractive?

You phrased it well in the beginning of the thread.
Why is it a "ring of death" when darkness in the arrows is praised?

 

[FB.]

David

I don't see how the ring of death looks much worse than the black arrows and some of my friends agree. That's why I started the thread.
Some people hate the ring of death. Some people hate the arrows. We have representatives of both sides posting on this thread. So maybe GIA didn't get it quite as wrong as is thought.
Perhaps, during the GIA observation study, when faced with a choice of black arrows or ring of death, enough people preferred a ring of death that GIA felt compelled to include it - to cater for all tastes. It just so happens that the cutters weren't likely to complain about being able to retain a little extra from the rough.

Perhaps - like our forum member e5116 - some observers in GIA's study might have vastly preferred a 33.5/41.4 instead of a steep/deep, as a way to get rid of the black arrows.

I don't know whether it's my eyes, or whether it's genuine, but an ideal cut has lots of small flashes of fire, compared to the "deep" pavilion stones (41.0-41.6), which seem to have many fewer flashes, but the flashes are larger and tend to "linger" for about twice as long as an ideal's firey flash.

 

[Rockdiamond]

I love you fb...ehehe

Seriously- thank you for looking at this with an open mind, and pointing out aspects of this I''ve been hammering away at for , literally, years.

Based on what you wrote FB, would you agree that the term "Ring of Death" is a bad choice of words? ( joining other pejorative terms like "steep deep" "obstruction issues" and the famous "leakage")

 

[Karl_K]

Date: 12/1/2009 6:52:02 PM
Author: FB.

Perhaps, during the GIA observation study, when faced with a choice of black arrows or ring of death, enough people preferred a ring of death that GIA felt compelled to include it - to cater for all tastes. It just so happens that the cutters weren't likely to complain about being able to retain a little extra from the rough.

Keep in mind that GIA grades are based on mostly industry observers not consumers.
Since many in the trade are used to seeing and selling steep/deep diamonds they didn't get downgraded.
Picture a room full of David's and that is who the GIA grades are based on.
Then add in an artificial lighting environment.
Result:
Near total disconnect from reality.

 

[Dancing Fire]

Date: 12/1/2009 3:48:37 PM
Author: kenny
Arrows are more a photography thing than a real life thing.

When I wear my ideal round I almost never notice the arrows, and they are never black.
They only stand out in photography and even then only when the photographer carefully positions the stone, on-axis, into the camera lens.
Next careful lighting can make the arrows stand out.

Yes in certain lighting I can place the stone precisely on axis and find the arrows but 99.99999% of the time in real life they are not visible.

They are only prominent here because we view zillions of well-taken pics of well-cut diamonds here on PS.
The arrows matter because are an indicator of good cut.

I surely hope people who have never seen a well cut diamond think they function like black arrows permanently painted onto the diamond, always present, and always black.

yep, not even on an 8*

 

[kenny]

EEK.
I forgot a word, don't.

My post should read:
I surely hope people who have never seen a well cut diamond don't think they function like black arrows permanently painted onto the diamond, always present, and always black.


I'm getting old.

 

[Karl_K]

Also keep in mind that these 2 combos both get the exact same grade from GIA because of the lower half rounding, if I added all the other rounding it gets even worse.

 

[FB.]

Date: 12/1/2009 7:07:38 PM
Author: Rockdiamond
I love you fb...ehehe

Seriously- thank you for looking at this with an open mind, and pointing out aspects of this I've been hammering away at for , literally, years.

Based on what you wrote FB, would you agree that the term 'Ring of Death' is a bad choice of words? ( joining other pejorative terms like 'steep deep' 'obstruction issues' and the famous 'leakage')

Well, maybe "ring of death" is a little harsh. But technically, the stone is leaking light at that point when viewed from directly above (although it doesn't leak when viewed from a 10' angle or more). I think that it would be desirable for a stone to avoid leaking light as much as possible (unless it's a fancy colour).
Not wanting to leak light, but wanting to dispose of the "obstructed arrows of death" is why my mention and interest in the 33.5/41.4 combo as an "arrow-less" substitute that is not leaking too much light.

 

[Rockdiamond]

Date: 12/1/2009 7:32:40 PM
Author: Karl_K
Also keep in mind that these 2 combos both get the exact same grade from GIA because of the lower half rounding, if I added all the other rounding it gets even worse.

Karl- your images showed the darkness more acutely.
The images look different than the ones FB posted- his seemed more....colorful(?)

Are yours based on a different lighting simulation/model?

 

[Rockdiamond]

Date: 12/1/2009 7:44:38 PM
Author: FB.

Date: 12/1/2009 7:07:38 PM
Author: Rockdiamond
I love you fb...ehehe

Seriously- thank you for looking at this with an open mind, and pointing out aspects of this I''ve been hammering away at for , literally, years.

Based on what you wrote FB, would you agree that the term ''Ring of Death'' is a bad choice of words? ( joining other pejorative terms like ''steep deep'' ''obstruction issues'' and the famous ''leakage'')

Well, maybe ''ring of death'' is a little harsh. But technically, the stone is leaking light at that point when viewed from directly above (although it doesn''t leak when viewed from a 10'' angle or more). I think that it would be desirable for a stone to avoid leaking light as much as possible (unless it''s a fancy colour).
Not wanting to leak light, but wanting to dispose of the ''obstructed arrows of death'' is why my mention and interest in the 33.5/41.4 combo as an ''arrow-less'' substitute that is not leaking too much light.

FB- the part in bold is where I disagree. Unquestionably dark blotchy areas where the diamond is reflecting the light downward ( referred to as leakage) will be seen as undesirable to many lovers of diamonds.
But with no leakage at all a diamond would have no dimension.
No matter how a diamond is cut as we move it some of the facets will reflect away from our eyes, or focus the reflection away from our eyes. It''s the pattern of reflection directly to our eyes, contrasted against the light reflected elsewhere that give the sparkle we love.
That''s why I question the use of the term "leakage" to describe this aspect of diamonds.
Saying a diamond may have "some dark areas that may be objectionable to some" seems a statement based in reality, and easily understandable.
Saying a diamond has "leakage" makes it sound bad. Sometimes the effect it describes is bad looking, and sometimes it''s not.

 

[Haven]

Date: 12/1/2009 3:42:02 PM
Author: Mrs Mitchell
I personally dislike the arrows. Took me a long time to admit that, since I get a strong feeling that we''re supposed to love ''em. Sorry, I just don''t.

I completely agree with this.
Some rbs have very obvious arrows to my eye, and I really dislike them.
Perhaps some people are arrow-sensitive, just as others are color-sensitive?

 

[Karl_K]

Date: 12/1/2009 11:01:29 PM
Author: Haven


Perhaps some people are arrow-sensitive, just as others are color-sensitive?

that is true I think.

 

[kenny]

Date: 12/1/2009 11:21:36 PM
Author: Karl_K

Date: 12/1/2009 11:01:29 PM
Author: Haven
Perhaps some people are arrow-sensitive, just as others are color-sensitive?

that is true I think.

No . . . those people are just arrow minded.

 

[Mrs Mitchell]

Hahaha! I think there''s something in what you say, Kenny. When I look at my ideal cut rounds, the arrows are the main thing I notice. Possibly because I *know* they are there, like if I''m looking at a stone I know to have an inclusion, once I''ve seen it, however long it took me to spot it, it''s the only thing I see thereafter. Yes, I''m arrow minded.

As for the ring of death, I''ve seen a few that are ugly. However, my current favourite diamond belongs to a classmate and it has something of a ring of death. Well, maybe more a ring of moderate illness, because it isn''t killing the stone by any means. I spend several hours a day looking at it (I will never graduate). It''s a beautiful stone with a big bold personality. I took it home with me last week to give it a good cleaning (had never been cleaned in 24 years and still caught my attention) and I''ve looked at it in a lot of different lighting conditions. I can''t say exactly why, but it''s one of if not the most attractive stone I''ve seen. I love it. It''s around 0.60ct, I wonder if the smaller size helps?

 

[Mrs Mitchell]

Date: 12/1/2009 6:52:02 PM
Author: FB.
David

I don''t see how the ring of death looks much worse than the black arrows and some of my friends agree. That''s why I started the thread.
Some people hate the ring of death. Some people hate the arrows. We have representatives of both sides posting on this thread. So maybe GIA didn''t get it quite as wrong as is thought.
Perhaps, during the GIA observation study, when faced with a choice of black arrows or ring of death, enough people preferred a ring of death that GIA felt compelled to include it - to cater for all tastes. It just so happens that the cutters weren''t likely to complain about being able to retain a little extra from the rough.

Perhaps - like our forum member e5116 - some observers in GIA''s study might have vastly preferred a 33.5/41.4 instead of a steep/deep, as a way to get rid of the black arrows.

I don''t know whether it''s my eyes, or whether it''s genuine, but an ideal cut has lots of small flashes of fire, compared to the ''deep'' pavilion stones (41.0-41.6), which seem to have many fewer flashes, but the flashes are larger and tend to ''linger'' for about twice as long as an ideal''s firey flash.

I notice the same on the flashes of fire, and I much prefer the larger, longer flash. I also prefer the simulations without the arrows, but it was interesting to see them lined up. My eye told me I didn''t care for those with the arrows, but part of my brain told me these were the ''better'' cuts. If I was picking a stone irl I would gravitate towards the ones on the right.