does color affect fire

[tommalle]

Does the color grade of a diamond affect the amount of fire a diamond has? From what I have been reading cut has a lot to do with fire but does a D colored diamond have less fire than a H colored diamond because the diamond itself is whiter? I have a D colored diamond. It throws around lots of white light and not so much colored light. I don''t mind it that way at all but I was just wondering why. My old diamond was a G and it did have a little bit more fire.

 

[LGK]

Nah, it's just a cut difference I think. Even within excellent cut parameters, there are diamonds with different personalities based on subtle differences in proportions- more bright white light, more fire, etc. Have you run across the abbreviations FIC, BIC, and TIC? In case you haven't, they stand for Fiery Ideal Cut, Brilliant Ideal Cut, and Tolkowski Ideal Cut. Or, a FIC is ideal cut that has slightly more fire and less white light, a BIC is vice versa, and a TIC has a good balance of both.

That being said, I think there is something about lower colors (like J and especially lower, where you can actually *see* color) that shows fire well- like the body color of the diamond makes the dispersion look more intense because of the contrast... that's just my opinion though, and I'm definitely biased in that I like lower colors like M, N etc.

 

[tommalle]

Those different abbreviations are for rounds only, right? It seems like most people have rounds and there is a lot of info on her pertaining to rounds. I personally like all of the fancy shapes, mostly pears and now I am liking ovals. I tend to see which direction everyone is going in and then I run the other way.

My sister in law has a round and I am not sure of the color but I know it is lower. That thing throws nothing but color all over the place. Mine is the total opposite. It is big and icy white and has tons of brilliance. The more I learn about diamonds the more I notice how different each one can be even with the same numbers they can look really different in person. Before joining PS I actually thought everyone lusted after big D flawless stones, I couldn''t be more wrong...

 

[Lorelei]

Date: 1/7/2009 10:14:44 PM
Author:tommalle
Does the color grade of a diamond affect the amount of fire a diamond has? From what I have been reading cut has a lot to do with fire but does a D colored diamond have less fire than a H colored diamond because the diamond itself is whiter? I have a D colored diamond. It throws around lots of white light and not so much colored light. I don't mind it that way at all but I was just wondering why. My old diamond was a G and it did have a little bit more fire.

Yes, the above abbreviations from LGK are for rounds only.

Fire is a result of proportions and angle combos of a diamond plus conducive lighting, also some configurations can aid fire production, some brilliance etc. I don't think diamond colour affects the colour of fire as far as I am aware. What you are noticing is more likely to be the result of how your two diamonds are cut, particularly the angle ranges.
Concerning fiery ideal cuts ( FIC), generally with these the crown angles are quite steep, combined with a suitable pavilion angle and smaller table. There can be tradeoffs with this type of diamond however as sometimes they have a bit of extra depth and may face up a little smaller for the weight.

This page might help also, http://diamonds.pricescope.com/brill.asp

 

[Garry H (Cut Nut)]

D should have more fire than a low colour like M because the body colour of the M can reduce the range of dispersion in the visible light range.

Between H and D no human could see a difference

 

[Lorelei]

Date: 1/8/2009 5:01:55 AM
Author: Garry H (Cut Nut)
D should have more fire than a low colour like M because the body colour of the M can reduce the range of dispersion in the visible light range.

Between H and D no human could see a difference

Thanks Garry, I was in fact curious about that!

 

[strmrdr]

Date: 1/8/2009 5:01:55 AM
Author: Garry H (Cut Nut)
D should have more fire than a low colour like M because the body colour of the M can reduce the range of dispersion in the visible light range.


Between H and D no human could see a difference

I question how noticeable it would be because the best lighting for fire is also the lighting that would be least affected by the extra absorption because there is plenty of intensity to overcome it.
In theory you are right.
I wonder about in actual practice....
Has someone done a study with identical cut diamonds?

 

[oldminer]

ImaGem does not report a measure of fire since fire is definitely a component of total light return, "Brilliancy". Fire measure does decrease incrementally as the color of a diamond becomes more colored when you eliminate the exact body color of a diamond from the measure. Of course, if one eliminates the exact body color you cannot then tell body color fire or light return apart. Fire is inherent in well cut diamonds and varies greatly as lighting varies. Total light return is a better constant measure to compute. If one casually includes body color as part of fire, then the measure is simply bogus and misleading to everyone.

Dr. Aggarwal has measured this decrease in "fire" for E to L color colored diamonds. It is only one of several reasons that ImaGem does not produce a fire measure. To say it isn''t much noticeable, is accurate, but we grade diamonds with levels way beyond what the eyes can see in order to create meaningful categories of quality. There is little difference in beauty or appearance between D and E color, but the financial change is quite important. Other examples readily apply, too.

People who want "measures" expect more than approximations or what is convenient to report. They want accuracy, and won''t accept a "measure" that we know changes as body color changes.

This is not the only reason for no fire measure, but it is a very good one.

 

[Phoenix]

I have various diamonds of D, E, F, G, H and K colours.

I can't see the difference in my D to G coloured diamonds, even H, in terms of fire, but my K colour diamonds *definitely* exhibit less fire than my other diamonds. I was worried that the cut wasn't as good in my K coloured diamonds but apparently (from my research) the reason for less fire is because the K's hold more body colour and therefore return less fire.

I thought the Gemex/ Brilliancescope tool (like the one that GOG uses) provides some measure of how much fire a diamond gives out (?).

 

[oldminer]

Brillianscope does report "fire", but as color gets to lower grades, it is my observation that they report more fire and less total light return..... We have studied this issue, but want to go forward without denigrating any competitor. It is just the way they appear to report their result. We don''t think a report of "fire" determines the quality of cut anyway.

Like I said, the better color diamonds show little difference to an observer in terms of loss of fire due to more body color, but that does not mean the loss does not exist or that smart tools can''t actually measure the decrease. Since increasing color does lower fire, it becomes a measure of lesser importance than a measure which remains far more relatively constant. There is room for different approaches and different points of view, but eventually we will have to make a consensus agreement.

 

[glitterata]

I think unless you''re comparing identical cuts, the comparison is somewhat meaningless. Won''t cut affect fire far more than color ever will (unless you''re talking about serious fancy colors)?

Of my various diamonds, far and away the most fiery is my L Old European Cut. I''m inclined to believe that''s because of the cut, not the color.

 

[strmrdr]

Date: 1/8/2009 7:23:04 PM
Author: glitterata
I think unless you''re comparing identical cuts, the comparison is somewhat meaningless. Won''t cut affect fire far more than color ever will (unless you''re talking about serious fancy colors)?


Of my various diamonds, far and away the most fiery is my L Old European Cut. I''m inclined to believe that''s because of the cut, not the color.

correct
cut has a huge effect so unless they are cut the same its apples to oranges.
What is interesting is that Paul''s production is consistent enough to make such a study possible if he has similar sized stones available in the 2 color grades.
We should ask Wink, John or Paul to look into this for us.

 

[Phoenix]

Date: 1/8/2009 8:53:27 PM
Author: strmrdr

Date: 1/8/2009 7:23:04 PM
Author: glitterata
I think unless you''re comparing identical cuts, the comparison is somewhat meaningless. Won''t cut affect fire far more than color ever will (unless you''re talking about serious fancy colors)?


Of my various diamonds, far and away the most fiery is my L Old European Cut. I''m inclined to believe that''s because of the cut, not the color.

correct
cut has a huge effect so unless they are cut the same its apples to oranges.
What is interesting is that Paul''s production is consistent enough to make such a study possible if he has similar sized stones available in the 2 color grades.
We should ask Wink, John or Paul to look into this for us.

Glitterata, I was comparing apples to apples. In fact, my K coloured stones are slightly better cut than my other coloured diamonds and yet give out less fire - visbly!!

I second Storm''s request.

I''d like to buy lowered coloured diamonds in order to increase my size but not at the expense of fire - if indeed this is the case.

 

[glitterata]

Phoenix, are the diamonds you''re comparing not just equally well cut, but cut the same way? With the same angles, I mean?

I seem to recall Wink saying on a recent thread that he believes diamonds in warmer colors are MORE fiery. I hope he pops in on this thread to comment.

 

[Phoenix]

Date: 1/8/2009 9:47:52 PM
Author: glitterata
Phoenix, are the diamonds you're comparing not just equally well cut, but cut the same way? With the same angles, I mean?

I seem to recall Wink saying on a recent thread that he believes diamonds in warmer colors are MORE fiery. I hope he pops in on this thread to comment.

No, they're not cut with the same angles, but similar enough and all ideal cut. In my novice opinion and to my untrained eye (LOL), all the higher coloured diamonds are similarly firey and they are much more firey than my K's. That, is enough for me to wonder if the lack of fire is *solely* attributable to the lower colour (?).

I really hope Wink pops in to comment. Thanks to Garry, Dave and Storm - all of whose expert opinions are greatly appreciated.

 

[WinkHPD]

Date: 1/8/2009 5:01:55 AM
Author: Garry H (Cut Nut)
D should have more fire than a low colour like M because the body colour of the M can reduce the range of dispersion in the visible light range.


Between H and D no human could see a difference

Garry, my personal observations would disagree with that statement. I see more fire in the lower colors because of the contrast between the yellow body color and the colors of the dispersion. I am talking about two AGS 0 (ideal) cut diamonds such as those that Infinity cuts. I can not speak for other cuts.

Wink

 

[WinkHPD]

Date: 1/8/2009 8:53:27 PM
Author: strmrdr

Date: 1/8/2009 7:23:04 PM

Author: glitterata

I think unless you''re comparing identical cuts, the comparison is somewhat meaningless. Won''t cut affect fire far more than color ever will (unless you''re talking about serious fancy colors)?



Of my various diamonds, far and away the most fiery is my L Old European Cut. I''m inclined to believe that''s because of the cut, not the color.

correct

cut has a huge effect so unless they are cut the same its apples to oranges.

What is interesting is that Paul''s production is consistent enough to make such a study possible if he has similar sized stones available in the 2 color grades.

We should ask Wink, John or Paul to look into this for us.

Thanks Storm. I can not give any scientific numbers, but can report only my observations, which are in contrast to the comments of Garry and Oldminer. Many of my clients have looked at two identically cut gems side by side and agree with me that the appearance of fire is brighter in the lower colors. Whether the quantity is more or less I can not say. I will say that both are beautiful, and that personal preference rules far more than paper when stones are shown side by side without a discussion of quality grades done before hand.

Wink

 

[Paul-Antwerp]

I saw this morning that my opinion was asked for in this thread. Thank you, Storm.

The problem is that I have a lot to say, but I do not know if any of this is meaningful. Therefore, please take all the following with a huge grain of salt.

As for Garry''s statement that a higher colour should exhibit more fire than the same lower colour, I have no reason to doubt the technical correctness of this.

On the other hand, I also have no reason to doubt Wink''s visual observation, where he reports the opposite.

I also found David''s remark very interesting, where he indicated that Imagem decided for very clear reasons not to include a Fire-measure in their report.

Personally, I find it very hard to report on fire. Trained in diamond-cutting-houses, I am used to observing diamonds in office-environments that do not lend themselves to showing fire. On top of that, in our Dutch diamond-slang, we have been trained incorrectly and we use the term ''vuur'' (literally translated fire) when we are observing scintillation. On top of that, I wear glasses, and I have heard that this reduces the possibility of observing fire. I am not even sure if this last statement is correct.

I am definitely sure that there is a difference between the fire produced by a stone, and the fire being observed. Technically, this might pose a problem since one person may take about what is produced and the other about what is observed. There may be differences there.

Also, as for Garry''s technical statement, I wonder what the effect is of the extra nitrogen in a lower-coloured diamond. There might be a marginal effect on the refractive index of such a stone. But also that is pure speculation.

On top of that, I think that this is highly personal. Some people are more receptive than others when observing fire, I am sure. In that way, I highly doubt the exactness of a few persons trying to observe a small number of our almost-identical stones. Especially since the observation of fire is highly environment-dependent too.

I also wonder if we are not trying to split hairs here. Garry, you remember the L-colour princess that Lieve is wearing, and that you saw at JCK last year. I do not remember your colour-guess face-up, but I do remember one jeweler estimating F. Granted, this was in perfect conditions, under a white suncover outside at the pool on a rather cloudy Las Vegas morning. In other light environments, the stone clearly has a warmer colour and it shows fire like crazy. Do we not agree that Cut-quality probably overcomes any marginal deduction of potential fire due to a lower colour?

I am sorry for all the ''mights'' and speculations in this post. I am unqualified to give a more definite answer.

Live long,

 

[Garry H (Cut Nut)]

After a few very nice glasses of wine tonight, I have to say that Wink and Paul all make wonderful statements. I have no desire to challenge them, and my first D statement was a technical one that can easily fall to ones based on physical observations.

Physics rules!!!!!!

The only value I can add is that we grade color thru the side of the stone and that is clearly the wrong way because we look at the diamonds face up.

 

[oldminer]

Darker colored diamonds often look like they are producing more fire when it is simply more of their colored body color which the observer is seeing. Being able to separate body color transmission from the actual production of fire is a huge stumbling block in making fire a metric.

I fully agree wih Garry that grading color in diamonds should eventually become a face-up situation. I think machines will be utilized especially to tell the finest colors apart, but that is a future prediction and not today''s reality.

 

[Serg]

Date: 1/8/2009 9:54:59 PM
Author: Wink

Date: 1/8/2009 5:01:55 AM
Author: Garry H (Cut Nut)
D should have more fire than a low colour like M because the body colour of the M can reduce the range of dispersion in the visible light range.


Between H and D no human could see a difference

Garry, my personal observations would disagree with that statement. I see more fire in the lower colors because of the contrast between the yellow body color and the colors of the dispersion. I am talking about two AGS 0 (ideal) cut diamonds such as those that Infinity cuts. I can not speak for other cuts.

Wink

re:I am talking about two AGS 0 (ideal) cut diamonds such as those that Infinity cuts

Wink, Could you please publish parameters and size ( or better 3D models) for this two cuts?
I do not think what difference between H and D could be enough to create better Fire contrast even for professionals

 

[WinkHPD]

Date: 1/9/2009 9:33:41 AM
Author: Serg

Date: 1/8/2009 9:54:59 PM

Author: Wink

Date: 1/8/2009 5:01:55 AM

Author: Garry H (Cut Nut)

D should have more fire than a low colour like M because the body colour of the M can reduce the range of dispersion in the visible light range.



Between H and D no human could see a difference

Garry, my personal observations would disagree with that statement. I see more fire in the lower colors because of the contrast between the yellow body color and the colors of the dispersion. I am talking about two AGS 0 (ideal) cut diamonds such as those that Infinity cuts. I can not speak for other cuts.


Wink

re:I am talking about two AGS 0 (ideal) cut diamonds such as those that Infinity cuts


Wink, Could you please publish parameters and size ( or better 3D models) for this two cuts?

I do not think what difference between H and D could be enough to create better Fire contrast even for professionals

I am talking about differences between D and J and M an other low colors in Crafted by Infinity diamonds that are AGS 0 (Ideal) Hearts and Arrows quality cutting. I have seen it many times and with many different diamonds. One of the most dramatic was between a 2ct D and a 3ct J, both Crafted by Infinity diamonds.

I am not talking scientific measurements, but visual observations. Not only mine, but those of many of my clients and also in discussions with many of my peers. Even if technically there is less dispersion, the appearance of the dispersion is, at least to many of us, greater. I do not know why, nor am I interested in trying to prove it, because even if I am scientifically wrong, my observations are correct for me and for those who perceive it the same way.

Not all perceptions of beauty can, or even should be, reduced to numbers on a paper.

Wink

 

[Serg]

Date: 1/9/2009 10:44:04 AM
Author: Wink

Date: 1/9/2009 9:33:41 AM
Author: Serg

Date: 1/8/2009 9:54:59 PM

Author: Wink

Date: 1/8/2009 5:01:55 AM

Author: Garry H (Cut Nut)

D should have more fire than a low colour like M because the body colour of the M can reduce the range of dispersion in the visible light range.



Between H and D no human could see a difference

Garry, my personal observations would disagree with that statement. I see more fire in the lower colors because of the contrast between the yellow body color and the colors of the dispersion. I am talking about two AGS 0 (ideal) cut diamonds such as those that Infinity cuts. I can not speak for other cuts.


Wink

re:I am talking about two AGS 0 (ideal) cut diamonds such as those that Infinity cuts


Wink, Could you please publish parameters and size ( or better 3D models) for this two cuts?

I do not think what difference between H and D could be enough to create better Fire contrast even for professionals

I am talking about differences between D and J and M an other low colors in Crafted by Infinity diamonds that are AGS 0 (Ideal) Hearts and Arrows quality cutting. I have seen it many times and with many different diamonds. One of the most dramatic was between a 2ct D and a 3ct J, both Crafted by Infinity diamonds.

I am not talking scientific measurements, but visual observations. Not only mine, but those of many of my clients and also in discussions with many of my peers. Even if technically there is less dispersion, the appearance of the dispersion is, at least to many of us, greater. I do not know why, nor am I interested in trying to prove it, because even if I am scientifically wrong, my observations are correct for me and for those who perceive it the same way.

Not all perceptions of beauty can, or even should be, reduced to numbers on a paper.

Wink

Wink,
I did not do any research in this field . I believe what you clear saw more fire in 3Ct J than in 2 Ct D,
But I think if we compare 3ct J and 2ct D, 3ct could give more important input than J color. So important to compare parameters( cuts) and facet flatness .
At least I do not see reason for statement what “lower color is increase Fire(Fire contrast)” if lower color diamond has bigger mass and other parameters had not been checked

 

[Rockdiamond]

Interesting thread!

Personally I do not believe that a correlation between color and "fire" can be made.....but I''m also in the category that Wink defined- I use physical observation

I recently looked at a really well cut 1.99carat round diamond that GIA had graded "Fancy Yellow". The stone had amazing sparkle and life ( I suppose you could call it "fire")
As Paul mentioned, the use of the word "fire" leads to ambiguities.


Grading Face up seems to make a whole lot of sense.
There are many cases of near colorless stones- or even those in the L-M-N range where a well trained grader won''t be able to spot the color face up..

 

[strmrdr]

Thank you to everyone that weighted in on this issue.

I have seen some lower colored rounds but didn't really pay that much attention to them but I have seen a couple l/m asschers and I absolutely loved them!
They were old cuts which made them even better! (high crown 1920s originals)

 

[Serg]

Date: 1/9/2009 1:03:44 PM
Author: Rockdiamond
Interesting thread!

Personally I do not believe that a correlation between color and ''fire'' can be made.....but I''m also in the category that Wink defined- I use physical observation

I recently looked at a really well cut 1.99carat round diamond that GIA had graded ''Fancy Yellow''. The stone had amazing sparkle and life ( I suppose you could call it ''fire'')
As Paul mentioned, the use of the word ''fire'' leads to ambiguities.


Grading Face up seems to make a whole lot of sense.
There are many cases of near colorless stones- or even those in the L-M-N range where a well trained grader won''t be able to spot the color face up..

re:but I''m also in the category that Wink defined- I use physical observation .I recently looked at a really well cut 1.99carat round diamond that GIA had graded ''Fancy Yellow''

David,
Fancy color is quite other story, of course Fancy colors background ( instead colorless J) could shift visual perception of Fire

 

[Rockdiamond]

Fancy color is quite other story, of course Fancy colors background ( instead colorless J) could shift visual perception of Fire

True Serg!

But I am also of the belief that the color grading system has certain deficiencies.
For example- a stone graded U-V color by GIA will show some color- set it properly in Yellow Gold and it can look like a "Canary".
Although it''s not a "Fancy Color" based on the name of the GIA grade, many if not most observers, will see it as a fancy color.

Which kind of proves my point- IMO a diamond''s color and it''s fire are two separate issues.

 

[oldminer]

"A diamond's color and fire are two separate issues." I agree and they should not be co-mingled to create a faulty fire metric.

There were several comments about what the grader "sees" as being sufficient for a response. That's fine, but it is no grading system. Besides, the existing system these folks use for color and clarity depend greatly on categories finer than what they can "see". Since we want to grade diamonds this way for color and clarity it certainly makes much more sense to grade light return and any fire that is going to be measured with equally fine categories beyond just what the eyes can see. I assure you that colored light return from a diamond can be measured far more accurately than what your eyes can appreciate.

If we want to grade diamonds with only what the eyes see then we might have the following system for color: DEF GH IJ KL MNOP QRSTU VWXYZ 7 categories instead of 23

If you follow this with clarity you might then have FLIF VVS1toSI1 SI2I1 I2I3 Only four basic categories.

No one would recommend or suggest such a change in the way the existing GIA system works. Since we tend to constantly make finer and finer distinctions with technology, it only seems logical to adopt finely categorized metrics and leave the uninformed grading of "what my eyes can see" to the retail sales staff at department stores and chains. I know it is tempting to simplify down to what the naked eye sees, but this is just not how diamonds are "graded". That's the point I am attempting to make.

I often recommend GHI color diamonds and VS1 to SI1 clarity diamonds to friends and consumers as being "very nice and probably good enough to make most folks happy", but that is to help shoppers, not to subvert the system of pricing or grading.

 

[WinkHPD]

We seem to be wandering into an area that confuses me.

I think our original poster asked an interesting question, and I am probably remiss in not having noted that he/she was talking about a D-G difference. I agree with Sergey and others who have said it is unlikely to notice a difference at this small a differentiation in colors, especially since this is not an easy grade difference to see from a face up position in two AGS Ideal cut diamonds.

I do not think this is a grading issue, or even a grading system issue, I think this is a perception issue, and that is all I have ever tried to say. I have said, and continue to say that my observations are not science, nor intended to be science, just an interesting observation. Ten years ago it would have been hard to get me to agree to show you a stone lower than an H, now I not only show them, but sell them. Why?

Because when well cut, they are BEAUTIFUL.

No science, rocket or other wise, just BEAUTIFUL.

Wink

 

[Rockdiamond]

I''ve always felt that if a machine could see things the eye can''t, the results are meaningless when judging a diamond.
After all, we could use 100 power microscopes instead of loupes.
This is only- to quite Wink again- my observation- I''m sure there''s scientific data to prove otherwise.
But I also disagree that the differences between a D an E and an F are impossible to see. Difficult yes. Impossible, no.
I don''t think that you were trying to say there''s no difference David- rather making a point.

In terms of "what my eye can see" it goes way further than uninformed retail salespeople.
IN my job as diamond buyer, "what my eyes can see" means EVERYTHING.
Sometimes a stone is lucky, and gets graded Fancy Yellow, when it''s really a Fancy Light Yellow.
In this case, my eyes see one thing, but the cutter is going to try to go only by the GIA report.
Such a stone is generally, not a great one to purchase, UNLESS- the cutter prices it based on how it looks as opposed to the GIA color grade.
The opposite stone- one that might get Fancy Yellow on most days, but got Fancy Light Yellow on the day it was graded could be a good stone to buy. No matter how hard the cutter cries that it''s Fancy Yellow, we''re going to pay for a Fancy Light Yellow, if we''re buying it.

At this point, GIA is still using human observation to grade color and clarity- which means they also feel that what the eye sees is most important. I don''t believe that''s about to change.