Question for the Color Sensitive Ladies/Gents.

[Garry H (Cut Nut)]

Dear Carrot,

You seemed to have raised the ire of some folk

That is not a bad thing if it helps educate people.

A couple of observations after skimming this last lot of posts.

The picture here shows the modeled variation in color of diamond that can result in different types of cut. In the face up position there is clearly a difference between the color we see in a round brilliant and a princess. It is no accident that most fancy yellow diamonds are made darker, and hence more valuable, by not making them round brilliants. So when folk say "my diamond looks whiter because it is a well cut round brilliant" they are reporting a well known and scientifically evident bit of physics. if you or oters want to learn more about this then this link is where we are discussing the lighting types that GIA used in its Cut study and its new grading system. Yuri, Sergey and Marty are scientists who know what they are talking about. Note that fire is not greatly impacted by the absorption of specific blue wave lengths - there are technical reasons for this, but one way to experiment yourself is to look for green fire in any diamond - it is rare. Yellow is the next rarest; this has nothing to do with nitrogen type blue absorption.
https://www.pricescope.com/community/threads/why-did-gia-included-steep-deep-diamonds-in-excellent.32135/page-4

Other comments people made - like is D really rare. Yes it is - do a search for G, or H, or I and see how many round brilliants are listed on Pricescope, then try D and E.

I regulalry test people buying diamonds and very few can see D - G, and about 50% can pick D from H in shaded daylight in well cut rounds. Princess and other cuts are a different story - one reason I do not like radiants in colourless stones is they show color more.
No one can pick the brilliance and fire difference between D and G stones.

 

[aljdewey]

Date: 8/19/2005 6:42:58 AM
Author: TimeTraveller
What a fiesty thread.

I respect and highly value posts made by both aljdewey and sjz. aljdewey, you may find it a surprise when I say that generally, I very much look forward to your posts in any thread because I usually find you're the voice of reason with lots of objectivity. So before reading any further, I want to re-iterate how much I generally value your posts and I hold your opinions in high regard.

Actually, I am surprised.....surprised and highly flattered. Very much.

Thanks for such a nice sentiment!

However, with this specific topic, I side completely with Mr Carrot and sjz. With due respect aljdewey, it really does not matter that you and Mara are color-insensitive. Color may be subjective when you're looking at it, but color or the lack of color as it exists in nature is objective--not subjective. The very fact that you and Mara are color in-sensitive actually should make general readers more cautious when reading your posts on the subject of color. You may not perceive the color difference, but others might very well.

I think, TT, that this whole thread got a bit off track simply because someone else said (paraphrasing).."in general, well cut stones in lower colors will face up similarly to higher colors." That ultimately turned this whole thing into a J debate for some, and for me, that's totally NOT what it's about. I'll tell you honestly, I couldn't give a rat's behind whether anyone, *myself* included, buys or likes a J stone. Truly.

I know it's a very subtle distinction, but there IS a difference between saying "my J looks like a G" and "I cannot see a color difference between my J and my H stones, BUT THAT DOESN'T MEAN YOU WOULDN'T." I capitalize this last part not to yell at you, TT, or anyone else, but it seems many keep missing this very important qualifier.

If I say "this is how I see it, but you may not", that should NOT be interpreted to mean "ALL J stones will face up like G stones." That's not what it says, and it's not what it means. Further, as Mara mentioned before, people come here for opinions. The original poster was asking if the color difference between the F and the G stones bothered a group of folks. If one person say "yeah, it bothers me", does that mean everyone should think that it WILL unequivocally bother everyone else? Of course not.

If I say "my H stones faces up like a G", does that mean I think my H *IS* a G? No, of course not. It's an H. It just means that *I*....individually.....perceive the way my diamond faces up to be similar to a G. That's IT.....period. Nothing else meant or intended. It doesn't say you will, and it doesn't say "there's no difference between a G and an H". It says only what it says....that when I look at my H and G stones, it looks to ME like my H faces up like a G.

Of course, since I'm the one saying it, I expect people with an IQ above room temperature to comprehend that I'm offering an OPINION. I'm not a GG, and never claimed to be. I really don't see how that should be confusing. NOW......if I walked around with that appendage Rich Sherwood (the 25+-years-in-the-business-appraiser) has perpetually rooted to his head, had 20 loupes hanging from my arm, and generally looked to be IMPERSONATING an appraiser or gemologist, then yes, I could understand the confusion.

I respect what you've said, TT, and more than that, I respect the lack of hysteria in which you've expressed it.

But I have to say that I feel there is a valued place and space at Pricescope for people to be comfortable sharing how they feel about their stone's color, clarity, tinge, or any other thing. People have to stop interpreting personal opinions as absolutes that have to apply to everyone the same way.

If I say "I prefer vanilla cream", does that mean I'm saying anyone who tastes ice cream will unequivocally prefer, or even LIKE, vanilla ice cream, too? Gosh, how awful would THAT be......we'd have a bunch of unhappy, vanilla-eating people! But if I say I prefer vanilla, and you say you prefer chocolate, then maybe......just maybe......someone reading that will go try BOTH for himself, and then he will know which he prefers.

I may say "I can't perceive tinge in I-colored stones", and you may say "I begin to see tinge in H stones." I expect any reader to know that 1) both are individaul perceptions, and 2) that two people don't see them the same way, so ERGO: Not everyone sees H/I stones the same way, and that means he himself will have to get his fanny out of his armchair and go look at H and I stones himself if he wants to be completely satisfied.

That's the whole point here....for people to give opinions on what works for each of them, and for the reader to use that information NOT as fact, but to help HIM determine HIS preferences. If that point is lost on some folks who just can't or won't appreciate that......well, that's just a shame....and it's their problem to get over.

 

[Richard Sherwood]

Date: 8/19/2005 7:23:30 PM
Author: carrot

The very fact that certain frequencies are filtered out means that less light is leaving the diamond than entered it and this absorption is another factor contributing to light loss that (by definition) reduces the overall light return.

All of that said, I invite any objective diamond buyer to compare a (zero fluorescence) well cut D color diamond to a well cut G color diamond in direct sunlight. If you can''t see the difference, buy the cheaper stone!

When comparing a top performing "D" to a "G", the only perceived difference will be the body color of the diamond, not the amount of light return or intensity of fire.

While your argument holds true on the "macro" level of sunglasses, the perceived difference on the "micro" level of trace element color absorption is imperceptible to the human eye, other than the resultant body color perceived.

What is true "by definition" is not necessarily observable "in practice". It makes no difference to a person that a bullet drops six inches at a thousand yards when it has been fired at him from six feet. The nuance of the physics escapes him.

 

[Richard Sherwood]

Date: 8/19/2005 9:57:34 PM
Author: aljdewey

NOW......if I walked around with that appendage Rich Sherwood (the 25+-years-in-the-business-appraiser) has perpetually rooted to his head, had 20 loupes hanging from my arm, and generally looked to be IMPERSONATING an appraiser or gemologist, then yes, I could understand the confusion.

You must have missed my new picture, Alj. I had the appendage surgically removed.

 

[Garry H (Cut Nut)]

(I have reposted this with the photo rescaled and a few slight edits)

Dear Carrot,

You seemed to have raised the ire of some folk

That is not a bad thing if it helps educate people.

A couple of observations after skimming this last lot of posts.

The picture here shows the modeled variation in color of diamond that can result in different types of cut modelled with the exact same absorption. In the face up position there is clearly a difference between the color we see in a round brilliant and a princess. It is no accident that most fancy yellow diamonds are made darker, and hence more valuable, by not making them round brilliants. So when folk say "my diamond looks whiter because it is a well cut round brilliant" they are reporting a well known and scientifically evident bit of physics. if you or oters want to learn more about this then this link is where we are discussing the lighting types that GIA used in its Cut study and its new grading system. Yuri, Sergey and Marty are scientists who know what they are talking about. Note that fire is not greatly impacted by the absorption of specific blue wave lengths - there are technical reasons for this, but one way to experiment yourself is to look for green fire in any diamond - it is rare. Yellow is the next rarest; this has nothing to do with nitrogen type blue absorption.
https://www.pricescope.com/community/threads/why-did-gia-included-steep-deep-diamonds-in-excellent.32135/page-4

Other comments people made - like is D really rare. Yes it is - do a search for G, or H, or I and see how many round brilliants are listed on Pricescope, then try D and E.

I regulalry test people buying diamonds and very few can see D - G, and about 50% can pick D from H in shaded daylight in well cut rounds. Princess and other cuts are a different story - one reason I do not like radiants in colourless stones is they show color more.
No one can pick the brilliance and fire difference between D and G stones.

Also you describe in some detail how red light is refracted more strongly than blue. Sorry mate, this is wrong. Red emerges from an optically denser material as the least refracted wavelengths.

And, as Rich says, the features you are expecting peple to be able to percieve as a result of absorption are simply too slight to 'see'.

 

[aljdewey]

Date: 8/19/2005 11:16:36 PM
Author: Richard Sherwood


You must have missed my new picture, Alj. I had the appendage surgically removed.

BAH! I didn''t miss it. I know that picture you have up there now was taken circa 1970.......pre-growth!

LMAO!

But we love ya, Rich......sans headlamp or not.

Seriously, I''ve been known to have a thing for men named Rich.

 

[aljdewey]

Date: 8/19/2005 11:07:00 PM
Author: Richard Sherwood

What is true 'by definition' is not necessarily observable 'in practice'.

Ahhhh.....in one sentence, he captures the essence of the point. That's just SO good, I'm gonna have to steal it.....hope you don't mind, Rich.

 

[carrot]

"Also you describe in some detail how red light is refracted more strongly than blue. Sorry mate, this is wrong. Red emerges from an optically denser material as the least refracted wavelengths."


Gary H is correct. The shorter wavelengths (blue, violet) are bent the most and the longer wavelengths (reds) are bent the least.

This is the reason that as the sun sinks below the horizon, reds are seen last. (Although scattering of light by the atmosphere is also a factor in that the shorter wavelengths are scattered away as the sunlight travels a greater distance through the atmosphere when it strikes at a more oblique angle.)

 

[Demelza]

Date: 8/19/2005 7:23:30 PM
Author: carrot
'Thanks for the clarification, Rich. That was very helpful.'

Well, you got the response you were looking for. Unfortunately (with all due respect to Mr. Sherwood) it is not true because physically, it cannot be true.

Carrot -- I'm not sure what you're implying here. I invited the experts to chime in here because it seems like an important issue. As someone who owns a near colorless stone, I wanted to know whether the performance of my diamond is affected by its color grade and I would imagine others here would be interested to know the same. You're making a fairly large claim there -- one which I have never heard asserted or even hinted at in all my time on PS. That in and of itself doesn't mean it's not true, but it seems worth exploring before people start thinking that the only way they can get a top performing diamond is to buy a D. If your eyes tell you that a D diamond produces the best light return, then you should only buy D diamonds. Based on what Rich and Garry have said, however, it doesn't sound like that is actually true in practice. Isn't that a good thing? No one is saying D color diamonds aren't beautiful, but isn't it great that other color diamonds can produce wonderful results as well? As I see it, it's a matter of preference. Some people like icy white diamonds, others appreciate the subtle warmth of near colorless grades, others can't tell the difference between the 2, and still others might prefer a whiter diamond but are willing to sacrifice color for size or clarity. The good news, as I see it, is that no one needs to sacrifice light return as long as the diamond is well-cut. Hooray!

 

[Garry H (Cut Nut)]

Date: 8/20/2005 1:02:37 PM
Author: Demelza

Date: 8/19/2005 7:23:30 PM
Author: carrot
''Thanks for the clarification, Rich. That was very helpful.''

Well, you got the response you were looking for. Unfortunately (with all due respect to Mr. Sherwood) it is not true because physically, it cannot be true.

Carrot -- I''m not sure what you''re implying here. I invited the experts to chime in here because it seems like an important issue. As someone who owns a near colorless stone, I wanted to know whether the performance of my diamond is affected by its color grade and I would imagine others here would be interested to know the same. You''re making a fairly large claim there -- one which I have never heard asserted or even hinted at in all my time on PS. That in and of itself doesn''t mean it''s not true, but it seems worth exploring before people start thinking that the only way they can get a top performing diamond is to buy a D. If your eyes tell you that a D diamond produces the best light return, then you should only buy D diamonds. Based on what Rich and Garry have said, however, it doesn''t sound like that is actually true in practice. Isn''t that a good thing? No one is saying D color diamonds aren''t beautiful, but isn''t it great that other color diamonds can produce wonderful results as well? As I see it, it''s a matter of preference. Some people like icy white diamonds, others appreciate the subtle warmth of near colorless grades, others can''t tell the difference between the 2, and still others might prefer a whiter diamond but are willing to sacrifice color for size or clarity. The good news, as I see it, is that no one needs to sacrifice light return as long as the diamond is well-cut. Hooray!

sucinct

 

[carrot]

Demelza, my apologies. That was poorly worded.


It was not my intention to attempt to raise the contribution of color grade to light return to the level of cut quality. It seems well recognized that cut quality is, by far, the most important consideration regarding light return. I don''t think I said that the only way to get a top performing diamond was to buy a D color stone, if top performing means a high level of light return.

Additionally, the primary considerations related to color grade were expressed earlier. My comments regarding transparency were intended to address an additional attribute of colorless stones, not to distract from or diminish the considerations that high color grade stones are worthy of by their very nature.

I find the transparency of a D color diamond more than just visible, it is breathtaking. As color grades diminish, so does the transparency. The stone is just not as clear, and I''m not talking about inclusions. Whether this makes a measurable contribution to light return or not is not of great importance to me. The overall impression of what I am seeing is. The "crystal clear" character of a colorless diamond speaks for itself. It doesn''t need to be quantified to appeal to me.

 

[Richard Sherwood]

Date: 8/20/2005 6:16:21 PM
Author: carrot

As color grades diminish, so does the transparency. The stone is just not as clear...

Carrot, I''m curious as to your experience with handling diamonds. Are you a member of the diamond trade in some respect?

Are you aware of anyone besides yourself who holds this position?

I''m not trying to hold your feet to the fire, I''m just curious.

 

[carrot]

Mr. Sherwood,

You could start with the dictionary.

transparent

adjective

1. Free from what obscures or dims

Transparency, permitting the free passage of electromagnetic radiation



You could also check here and here and here and here and here and here and here and here.

 

[sjz]

This has indeed been a very interesting and educational thread!

 

[Richard Sherwood]

Okay, now I begin to see where you're coming from. Good research job.

These sites all describe the difference in the D,E & F grades as being a difference in "transparency" rather than a difference in color, and then the other grades being progressively deeper shades of body color.

From this it seems you have extrapolated that there must be a consequent diminishment of perceivable brilliance and fire. And indeed, you've got one fellow agreeing with you on the first site listed, in which he states:

"It's mostly undetectable to the naked eye. Even so, a colorless diamond, like a clear window, allows more light to pass through which in turn gives more sparkle and fire compared to less transparent diamonds."

Like the question I asked you, I'd be curious what this person's experience in handling diamonds is, and whether he or she is a member of the diamond trade. No name, credentials, affilations, experience or location is mentioned anywhere in the site. It seems to be a "referral" site directing consumers to different vendors. My guess would be the person that made this statement is neither a gemologist or diamantaire.

The only (near) correct portion of this statement, in my opinion, is that "it's mostly undectable to the naked eye", although you could drop the "mostly".

The "transparency" referred to in these sites is referring to the subtle difference of body color (or tone) in the D, E & F grades. They're trying to describe the nuance of body tone in these "colorless" grades. As I grade diamonds daily, I understand what they are trying to convey, and it is not a diminishment of brilliance, nor fire.

I'll try an additional analogy, since the bullet analogy didn't seem to fly.

You're a burglar, walking through a dark room, when a pinpoint white light beam falls on your forehead. You freeze, your attention riveted to it's source. Then next to it, a pinpoint red light beam of the same candlepower falls on your forehead as well. All the components of the white light spectrum except red have been eliminated from this beam, yet I guarantee you it looks every bit as bright to the person perceiving it as the white. Some people might even perceive the concentration of color as being "more brilliant".

I've seen plenty of "M" color diamonds with as much brilliance and fire as a "D" color. There is no diminishment of these components, as well as no diminishment of the transparency of the crystal. Some factors can diminish diamond crystal transparency to the eye, but body color from trace mineral elements is not one of them. Unless I have missed it for the past twenty-six years.

 

[Garry H (Cut Nut)]

Date: 8/20/2005 10:35:43 PM
Author: carrot
Mr. Sherwood,

You could start with the dictionary.

transparent

adjective

1. Free from what obscures or dims

Transparency, permitting the free passage of electromagnetic radiation



You could also check here and here and here and here and here and here and here and here.

OK Carrot, we can see you have been led astray by some educational program that taught a lot of people the same clap trap.
This quote seems typical from one of your links
"Color grades D through F are so slight that they are best described as differences in transparency"

 

[sjz]

Richard or Garry, could either one of you speak to this question...will the presence of body color in a diamond affect the amount or type of colored flashes? This is something I've always wondered about, and now I kind of have an inkling after reading some of your posts. I own a fancy yellow colored stone, and have seen some chamgaigne colored diamonds as well. I don't seem to notice as many of the rainbow colored flashes of light coming from those colors as I do my whiter colored diamonds. They seem to have a great deal of sparkle and fire to my eye, though. Will there be less colored flahses or different colored flahses in a diamond with more hue or saturation of color than in a more colorless grade of diamond?

Sorry if my terminology isn't correct, but I hope one of you gets what I'm trying to say.

 

[Richard Sherwood]

Date: 8/21/2005 9:53:36 AM
Author: sjz

Richard or Garry, could either one of you speak to this question...will the presence of body color in a diamond affect the amount or type of colored flashes?

I own a fancy yellow colored stone, and have seen some chamgaigne colored diamonds as well. I don't seem to notice as many of the rainbow colored flashes of light coming from those colors as I do my whiter colored diamonds. They seem to have a great deal of sparkle and fire to my eye, though. Will there be less colored flahses or different colored flahses in a diamond with more hue or saturation of color than in a more colorless grade of diamond?

SJZ, probably what you're noticing is the typical difference in cut quality between a fancy colored diamond and a white diamond. Fancy colored diamonds are cut with the emphasis on bringing out the most saturated hue possible. Brilliance and fire concerns take a second place to this.

White diamonds however, rest upon their brilliance and fire for a major part of their appeal, and are cut to maximize these features.

 

[carrot]

"I also do not personally consider I colored to be a beautiful diamonds. "

Gary H (Cut Nut)

(from this thread)


Gary, would you be kind enough to explain what it is about the color grades of H and above that you find beautiful and why you do not find the color grade I and (presumably) below not beautiful?

 

[Serg]

I do not see any reason Why even F(G) can not be more transparent than D.

D is most white, it is not signify D is most transparent .

In any case Human eye can not distinguish transparency D 1 ct diamond from transparency F 1 ct diamond. You can see difference in color( Saturation) just

 

[sjz]

Date: 8/21/2005 11:16:27 AM
Author: Richard Sherwood

Date: 8/21/2005 9:53:36 AM
Author: sjz

Richard or Garry, could either one of you speak to this question...will the presence of body color in a diamond affect the amount or type of colored flashes?

I own a fancy yellow colored stone, and have seen some chamgaigne colored diamonds as well. I don''t seem to notice as many of the rainbow colored flashes of light coming from those colors as I do my whiter colored diamonds. They seem to have a great deal of sparkle and fire to my eye, though. Will there be less colored flahses or different colored flahses in a diamond with more hue or saturation of color than in a more colorless grade of diamond?

SJZ, probably what you''re noticing is the typical difference in cut quality between a fancy colored diamond and a white diamond. Fancy colored diamonds are cut with the emphasis on bringing out the most saturated hue possible. Brilliance and fire concerns take a second place to this.

White diamonds however, rest upon their brilliance and fire for a major part of their appeal, and are cut to maximize these features.

Oh wow, I never knew that. I''ve seen pictures of some of the world famous fancy colored diamonds, and they usually don''t appear to be symetrical to me. I always wondered why that was, and now I know!

Are the hues more saturated in different parts of the crystal in a fancy color? Is that why the cut focuses more on bringing out the hue saturation than light return? If I''m not getting this straight, I hope you let me know. This all really fascinates me!

 

[sjz]

Carrot, if you read this http://www.gia.edu/pdfs/04_Diamonds_optics_1.pdf#search="diamond optics" it will help to explain what Richard and Garry are talking about.

The fire and light return of diamonds isn't based as much on transparency as it is their reflective and refractive properties. Espcially their high percentage of refraction. A diamond has a 17% degree of refraction as opposed to transparent glass, which has a 4% degree of refraction. That's what makes the light return and sparkle of a diamond, not so much the transparency.

 

[carrot]

Serg,

When you use the term transparent, is it in the context of "an absence of a reduction in the ability to resolve detail" (as in the case of a camera lens which reduces certain wavelengths of light without reducing the resolution of an image) or "an absence of attenuation of any part of the visible spectrum" or both?

Are you saying that as saturation increases, transparency does not decrease?

Thanks.

 

[Garry H (Cut Nut)]

Sergey means it is possibly for a D color diamond to not transmit as much light as an F or G.
Not all the causes or reduced transperency are as a result of absorption of specific visible colored spectra.

Iabout H / I:
It is my experiance that this is the most critical boundary where people can see the biggest difference in colorless / tinted.
This is also reflected in the pricing of SI and VS clarity grades - I is a lot cheaper in Round Brilliants - it is a bigger jump than F/G or I/J. reason - more people find H more beautiful or desirable or whatever than I.

But I am yet to hear a customer say "This I does not sparkle as much."

 

[Serg]

Re: Are you saying that as saturation increases, transparency does not decrease?

Carrot,
Do you like games? I more prefer the work.

Colorless does not signify zero absorption. D color has absorption.

Do virtual experience: Take G diamond and increase absorption in yellow-red part spectrum. Which grade color could you receive? Could you receive D color?

You can do it in real world with K diamond and blue filter.

And of course diamond transparency depends from polish and cut