How GIA grades color in colorless vs. fancy colored diamonds

[kenny]

Based on what I've read here this is my understanding; Pros are welcome to correct me if my understanding is wrong.

Contrary to what many people would think, if you put two colorless GIA H round diamonds side by side, a 1 carat and a 10 carat, they will NOT look the same color.
You will see more color in the larger one, whether face-up looking into the top, or face down-looking into the side of the pavilion with a white background.

Here's my question.
Does GIA give the opposite consideration to weight when grading color intensity of fancy colored diamonds?

Here's why I suspect they do.
In the pic below are two green diamonds, both graded natural Fancy Intense Green by GIA with no color modifiers.
Both pics are from the same vendor, fancydiamonds.net. and have the same white background.
I have read here that this vendor has a good reputation for the honesty of their photography.

The cushion on the left is 2.36 ct and the round on the right is 0.26 ct, almost 10 times smaller.
Note the larger diamond on the left has much weaker color than the smaller one.
This is just the opposite of how GIA grades the color of colorless diamonds.

I realize fancy colors are graded face up and colorless are graded face down.
But that does not affect my question since I'm comparing a fancy color to a fancy color.
I also realize you can't judge color by pics but the difference here is so dramatic and in the opposite direction.

Apparently, larger colorless diamonds in the same color-intensity grade will have more color, but larger fancy colored diamonds in the same color-intensity grade will have less color.

Here are the stones:

The 2.36 ct cushion on the left: http://www.fancydiamonds.net/view_diamonds/3667.htm

The 0.26 ct round on the right: http://www.fancydiamonds.net/view_diamonds/4217.htm

 

[T L]

Re: How GIA grades color in colorless vs. fancy colored diam

Kenny,
Do you have the GIA Colored Diamonds Color Reference Charts? If you do, you would see that within each fancy designation (deep, vivid, intense, etc. . . ) there can be several different shades. Therefore, one fancy intense green may look a different color saturation and/or tone than another fancy intense green shade. For some reason, green isn't in the booklet , but, for example, yellow has about 20 various shades all within fancy deep.

Obviously, cutting a stone will change it's fancy designation. I think after the Whittelsbach was cut, it went from fancy deep greyish blue to fancy intense blue, or something like that. I forget, but the designation did change.

Did you get your green diamond yet? I'm waiting on pins and needles for photos.

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

Yes, I know each grade is a range of hue, tone, saturation etc. and GIA is notorious for their broad ranges within one color grade (fancydiamonds.net has 10 within each GIA grade, but still! come on!
Look at the enormous difference between those two identically-graded greens.
Look at the fact that one is almost 10 times the weight of the other.

I think my question is a reasonable and logical one.

 

[T L]

Re: How GIA grades color in colorless vs. fancy colored diam

Hmmm, I wouldn't really comment on them unless I saw them both side by side in person. I think lighting and colored diamonds often causes huge variations. I'm unsure how Leibish photographs their stones as well, and they may look closer in color if seen IRL next to each other under the same light source.

 

[movie zombie]

Re: How GIA grades color in colorless vs. fancy colored diam

it also appears to me that each stone is held at a different distance from the camera.....the one on the right being closer. this would effect color and could account for some difference in viewing, especially on a monitor.

Mo-Zo

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

Kenny,
Do you have the GIA Colored Diamonds Color Reference Charts? If you do, you would see that within each fancy designation (deep, vivid, intense, etc. . . ) there can be several different shades. Therefore, one fancy intense green may look a different color saturation and/or tone than another fancy intense green shade. For some reason, green isn't in the booklet , but, for example, yellow has about 20 various shades all within fancy deep.

Obviously, cutting a stone will change it's fancy designation. I think after the Whittelsbach was cut, it went from fancy deep greyish blue to fancy intense blue, or something like that. I forget, but the designation did change.

Did you get your green diamond yet? I'm waiting on pins and needles for photos.

I just ordered that chart, and the pink diamond one too. Thanks.
I wonder why GIA omitted green from the chart, but included yellow-green. Hmm.
I wonder if it is related to the difficulty of verifying natural origin of greens.
Perhaps they plan to produce one just for Green, like they did for Pink.

The greenie should be here in a week or so, that is if I don't forget to pick it up.
I get absent minded sometimes.

 

[soberguy]

Re: How GIA grades color in colorless vs. fancy colored diam

I can tell you only that the 4.25 carat natural fancy deep grayish violet I got to play with at Harry Winston was spot on to my eye. The color WAS a fantastic deep violet. The green diamond I played with at Harrod's was the same. I really think the distance from the camera has a lot to do with it also. It also looks like slightly different lighting maybe?? Or angle? Hmmmm... My fancy grayish yellowish green was described exactly right to my eye also... However, the natural fancy gray I have looks slightly bluish green to my eye... who really knows? lol!

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

I really think the distance from the camera has a lot to do with it also.

I think that has no effect.
If anything, would that not blowing up something small make the color of the smaller one MORE diluted, rather than more intense?
The 0.26 ct is blown up (probably by bringing the camera closer before the exposure) so it appears the same size as the 2.36 ct. in the above pic.

Frankly, I believe very strongly that changing the size of an image (especially when done before the pic is even taken) does nothing to the color saturation.

 

[nararabbit]

Re: How GIA grades color in colorless vs. fancy colored diam

I have no idea, just chiming in to say I agree with you. If anything, I think the larger diamond is a hideous color whereas the right one (your baby!) is just beautiful. That these two could be the same grade to me is mind-boggling. Also, I see color modifiers in the left diamond, I'm not sure why they graded it as being without - yours definitely appears to fit its grade. The other doesn't, in my mind...

 

[T L]

Re: How GIA grades color in colorless vs. fancy colored diam

I can tell you only that the 4.25 carat natural fancy deep grayish violet I got to play with at Harry Winston was spot on to my eye. The color WAS a fantastic deep violet. The green diamond I played with at Harrod's was the same. I really think the distance from the camera has a lot to do with it also. It also looks like slightly different lighting maybe?? Or angle? Hmmmm... My fancy grayish yellowish green was described exactly right to my eye also... However, the natural fancy gray I have looks slightly bluish green to my eye... who really knows? lol!

Colored diamonds are strange animals. Although we are able to see color clearly and confidently in colored gems, the color in some colored diamonds is far more subtle, and depending on the lighting, they can look more intense or far less saturated. This is especially true with blues and greens which tend to have a lot of grey in them. I will say that although the green cushion on the left may be unattractive to some people, it is a very rare and valuable color for a diamond, and I can see why it probably has a fancy intense grade. As for your small green, I have never seen a green that intense in color, and so I think it's prudent to judge it in person when you get it. For me, it defies what I see in most greens. I have never seen a minty green diamond with that much saturation. If it truly is how it looks in the photo, perhaps it should have been graded a fancy vivid, but I don't make those decisions.

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

. . . As for your small green, I have never seen a green that intense in color, and so I think it's prudent to judge it in person when you get it. For me, it defies what I see in most greens. I have never seen a minty green diamond with that much saturation. If it truly is how it looks in the photo, perhaps it should have been graded a fancy vivid, but I don't make those decisions.

Frankly I consider the color intensity to be perfect for this cut and size. (Perhaps I'm blinded by love. )
I don't think I'd even want this particular green gem to be more saturated.
I'd certainly not want to see what a Vivid grade would have done to its already sinus-clearing price.
You can really see into this green, almost as if it has its doors and windows proudly open.
Everything about that green is just right; gorgeous in any material but quintessential in a green diamond.

FWIW, it just emerged yesterday from GIA with a new full Colored Diamond Grading Report.
All specs matched the previous report including, most-importantly, the natural origin of that fresh minty green.

Now I have more peace of mind about this natural green diamond - the most risky color to buy.
Also it is nice to get verification no chips have happened since the last report.
To bad it didn't come in at 2.26 ct, a nice number; I was hoping there was some numerical error.

Hot off the press:

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

I certainly acknowledge that I'm no expert on how wide the range is within a GIA fancy color grade.
I hear again and again that the ranges are very wide.
I just ordered GIA's chart of Fancy Colored Diamonds http://store.gia.edu/ProductDetails.asp?ProductCode=colordiambooklet
Still I have a little bit of learning under my belt and the two diamond above have me puzzled.

Yes one diamond is almost 10 times the weight of the other so the camera had to be closer to the small round, but I think that has no effect.
If anything, wouldn't blowing up the small round make its color MORE diluted, rather than more intense?
Honestly, I believe very strongly that changing the size of an image (especially when done before the pic is even taken) does nothing to the color saturation.

I have no argument the GIA color intensity ranges are wide.
I have no argument that whites are graded face down and coloreds face up.
I have no argument that cut can greatly affect color intensity.
I have no argument that the only way to fairly compare these two would be live, side by side and one pic with both side by side is vastly superior to two separate pics.
I have no argument that lighting differences can affect how a diamond looks live and in a pic.
I have no argument that the lighting used by GIA is probably not identical to that used for these pics.

Even after agreeing with everything above that people have brought up . . . still . . . my question remains unanswered.
How is weight taken into account in GIA color grades?
Nothing brought up has answered my question and nothing brought up makes my question invalid.
It is a legit question.

I do not agree that throwing your hands up in the air and saying "Things vary" is a legit answer.
Yes, it is true that things vary, but there is an answer.
GIA graders know the answer.

Everyone understands and agrees in colorless diamonds a much larger stone of the same GIA color grade will show more color.
Is this also true for Fancy Colored diamonds, or is just the opposite as I suspect?
Or, does weight carry no weight whatsoever as has also been mentioned in this thread?

 

[Fly Girl]

Re: How GIA grades color in colorless vs. fancy colored diam

FWIW, it just emerged yesterday from GIA with a new full Colored Diamond Grading Report.
All specs matched the previous report including, most-importantly, the natural origin of that fresh minty green.

Woohoo! Looking forward to more pictures soon of your new pretty!!

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

Getting back to the question, here are 3 possible answers.

Much larger colored diamonds of same GIA color intensity grade will have . . .

1. more color
2. less color
3. the same

. . . than much smaller ones.

I'm sure GIA knows the answer.
Does anyone here?

 

[Leibish & Co.]

Re: How GIA grades color in colorless vs. fancy colored diam

hey all,

This are only my thoughts and my personal opinion...

-Different lighting is definitely a reason, if one stone was taken at a certain hour and another stone at a different hour, it can change the pic dramatically,(the camera is located next to the window in order to get as much Natural light as possible).

-Different angels of holding the stone, maybe more light came in? or the color was reflected differently due to the angle?

-not every stone is Photogenic, funny to say, but there are stones that are not good models, they just don't come up nice in pics, many black windows appear when the picture is taken, Yellow shades of lightning appear in the picture,and the overall appearance just doesn't look nice in a picture like the stone itself really looks, the 2.36ct is one of this kind of stones....doesn't look nice in a picture, but appears much nicer in real life.

-Different hours, different lightning, in hours that the lightning is not good, it can make the stone look much more dull than it really is,

-different levels of shades, ythe 0.26ct stone is very strong in color, the 2.36ct is less strong and has slightly different color(the biggest advantage of this stone is it's size, natural green in this sizes are extremely rare...).

I think the most important reason for the difference is that the 0.26ct has a much nicer color, i have wrote here before already that for some reason the 0.26ct picture appears too minty on Kennys screen, abit over saturated but still the color of the 0.26ct is just better than the 2.36, don't know if it has anything to do with the size, i can only say that it's a better color than the 2.36ct.

Most important, pics are just an illustration tool, we do our very best to have the best pictures as possible, but sometimes the way something looks through the lens may look a bit different in reality since so many factors come in the way. (for better or for worse).

Itzik

 

[T L]

Re: How GIA grades color in colorless vs. fancy colored diam

Itzik,
Have you ever thought of doing videos of stones? I think this would be a great selling tool, and I find that videos are so much better in conveying the true beauty of a colored diamond than a still photograph.

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

Thank you Itzik.

I hear everything you are saying and I understand that can explain the color difference we see.
I'll add that I am not in any way being critical of your photography, though controlled artificial lighting may offer less variable results.
In this age on Internet purchases, let's face it, many of us unfortunately DO depend on photography for our buying decisions.

We all here know of other vendors with intentionally misleading photography practices.
In this particular case a $550,000 green looking less saturated than another of the same grade that is 1/16th the price one would not benefit you, quite the opposite.
So nobody can suggest anything improper is going on here.

Also I understand each grade is a range not one point.

Still . . . even if I had not posted any pics or referenced any particular stones . . . do you, or your staff GG, know whether GIA gives some consideration to weight when grading the intensity of fancy colored diamonds?
Will much larger ones have less, more or the same range of color intensity?

I think everyone assumes if you put 1000 Fancy Intense Greens side by side in weights from one point to 100 carats that they all would fall within the same range.

 

[T L]

Re: How GIA grades color in colorless vs. fancy colored diam

I'm not Itzik, but from my understanding, size has nothing to do with how the GIA grades color. For example, a 20 point diamond and a 20 carat diamond with the same color, will be graded as the same color. Sometimes size causes a change in color (like when the Whittelsbach was recut), but that's a different topic. My only explanation for the above is that the Fancy Intense range of green has several tones and saturation sub-levels. Since Itzik mentioned your stone isn't as minty as the photo, then it's probably closer to the photo of the larger stone IRL than it is in your above comparison photos. Again, it is really important to judge it when you get it in person.

I do agree with Itzik that the sun's rays at a particular time of day can cause variations in color in colored diamonds.

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

Since Itzik mentioned your stone isn't as minty as the photo, then it's probably closer to the photo of the larger stone IRL than it is in your above comparison photos. Again, it is really important to judge it when you get it in person.

Agreed.

But Itzik did write this, " . . . I think the most important reason for the difference is that the 0.26ct has a much nicer color, . . . but still the color of the 0.26ct is just better than the 2.36, don't know if it has anything to do with the size, i can only say that it's a better color than the 2.36ct."

Yes, I know every grade is a range not a point.

Even if they looked identical green in person it is mind blowing that this round diamond (a less color-enhancing cut) 1/10 the weight could have the same strength of color.
That had to be some screaming rough.
I'm really curious if another larger stone was cut from the same rough.

 

[T L]

Re: How GIA grades color in colorless vs. fancy colored diam

Since Itzik mentioned your stone isn't as minty as the photo, then it's probably closer to the photo of the larger stone IRL than it is in your above comparison photos. Again, it is really important to judge it when you get it in person.

Agreed.

But Itzik did write this, " . . . I think the most important reason for the difference is that the 0.26ct has a much nicer color, . . . but still the color of the 0.26ct is just better than the 2.36, don't know if it has anything to do with the size, i can only say that it's a better color than the 2.36ct."

Yes, I know every grade is a range not a point.

Even if they looked identical green in person it is mind blowing that this round diamond (a less color-enhancing cut) 1/10 the weight could have the same strength of color.
That had to be some screaming rough.
I'm really curious if another larger stone was cut from the same rough.

It's really not mind blowing, it's just a stronger saturation for the size. That happens in colored gems all the time. If this stone were blown up to the size of the 2.36 carat gem, it would be more saturated than it is now. The color on your green may be much nicer than the color on the 2.36, but Itzik did say it's not as minty as the photo conveys, so again, (I know I'm beating a dead horse), it's really important to judge it when you get it in person.

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

Agreed, again.

Fortunately Leibish & Co. has a good return policy.
See screen capture I just took below.

 

[T L]

Re: How GIA grades color in colorless vs. fancy colored diam

Liebish is a fine upstanding company with a great reputation among the trade. You really have no worries.

 

[chrono]

Re: How GIA grades color in colorless vs. fancy colored diam

I’m sure you’ll experience no issues when it comes to returns and refunds to Liebish. Let’s just wait to see what it looks like when you receive it although it’s far less exciting than making all these presumptions.

 

[JewelFreak]

Re: How GIA grades color in colorless vs. fancy colored diam

Why are white graded face down & coloreds face up?

--- Laurie

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

Why are white graded face down & coloreds face up?

--- Laurie

Good question.
I don't know but that's never stopped me from opening my big mouth before . . .

Perhaps it is this.
Grading color face up would be preferred since diamonds are mounted face in jewelry up not face down - but the D-Z range of white diamonds results in tiny difference between grades, especially near D.
Face down shows body color better than face up so these tiny differences are easier to detect.

The color grades of fancy colors are much more easily discernible than in whites near D, so face up is fine for grading.

 

[Sagebrush]

Re: How GIA grades color in colorless vs. fancy colored diam

Based on what I've read here this is my understanding; Pros are welcome to correct me if my understanding is wrong.

Contrary to what many people would think, if you put two colorless GIA H round diamonds side by side, a 1 carat and a 10 carat, they will NOT look the same color.
You will see more color in the larger one, whether face-up looking into the top, or face down-looking into the side of the pavilion with a white background.

Here's my question.
Does GIA give the opposite consideration to weight when grading color intensity of fancy colored diamonds?


Neither of the above statements is correct.

I cover the subject of GIA's grading of fancy color diamonds fairly extensively in Secrets Of The Gem Trade. The GIA's approach is quite "theoretical". Remember that in the GIA system gray is not a hue! This is the key. Thus, it is often ignored. That is why gray stones with a hint of blue, i.e. The Wittelsbach becomes "fancy deep blue". The same holds with green. The gray is ignored but only as a hue, the sum total effect of the gray, i.e. the pumping up of the tone is not.

 

[kenny]

Re: How GIA grades color in colorless vs. fancy colored diam

Thanks Mr. Wise.
Your technical input is invaluable.

 

[T L]

Re: How GIA grades color in colorless vs. fancy colored diam

Based on what I've read here this is my understanding; Pros are welcome to correct me if my understanding is wrong.

Contrary to what many people would think, if you put two colorless GIA H round diamonds side by side, a 1 carat and a 10 carat, they will NOT look the same color.
You will see more color in the larger one, whether face-up looking into the top, or face down-looking into the side of the pavilion with a white background.

Here's my question.
Does GIA give the opposite consideration to weight when grading color intensity of fancy colored diamonds?


Neither of the above statements is correct.

I cover the subject of GIA's grading of fancy color diamonds fairly extensively in Secrets Of The Gem Trade. The GIA's approach is quite "theoretical". Remember that in the GIA system gray is not a hue! This is the key. Thus, it is often ignored. That is why gray stones with a hint of blue, i.e. The Wittelsbach becomes "fancy deep blue". The same holds with green. The gray is ignored but only as a hue, the sum total effect of the gray, i.e. the pumping up of the tone is not.

Then why are there colors like Fancy greyish blue? While I do agree that modifiers for the most part are ignored in grading colored diamonds, I do think that grey is sometimes uses in the determination of their color, almost like it were a hue. The Whittelsbach was a fancy deep greyish blue before it was cut.

 

[LD]

Re: How GIA grades color in colorless vs. fancy colored diam

Based on what I've read here this is my understanding; Pros are welcome to correct me if my understanding is wrong.

Contrary to what many people would think, if you put two colorless GIA H round diamonds side by side, a 1 carat and a 10 carat, they will NOT look the same color.
You will see more color in the larger one, whether face-up looking into the top, or face down-looking into the side of the pavilion with a white background.

Here's my question.
Does GIA give the opposite consideration to weight when grading color intensity of fancy colored diamonds?


Neither of the above statements is correct.

I cover the subject of GIA's grading of fancy color diamonds fairly extensively in Secrets Of The Gem Trade. The GIA's approach is quite "theoretical". Remember that in the GIA system gray is not a hue! This is the key. Thus, it is often ignored. That is why gray stones with a hint of blue, i.e. The Wittelsbach becomes "fancy deep blue". The same holds with green. The gray is ignored but only as a hue, the sum total effect of the gray, i.e. the pumping up of the tone is not.

I may be totally wrong but didn't the GIA class the Wittelsbach originally as fancy deep greyish blue (or something similar) but after the re-cut the grey was dropped?

 

[T L]

Re: How GIA grades color in colorless vs. fancy colored diam

Based on what I've read here this is my understanding; Pros are welcome to correct me if my understanding is wrong.

Contrary to what many people would think, if you put two colorless GIA H round diamonds side by side, a 1 carat and a 10 carat, they will NOT look the same color.
You will see more color in the larger one, whether face-up looking into the top, or face down-looking into the side of the pavilion with a white background.

Here's my question.
Does GIA give the opposite consideration to weight when grading color intensity of fancy colored diamonds?


Neither of the above statements is correct.

I cover the subject of GIA's grading of fancy color diamonds fairly extensively in Secrets Of The Gem Trade. The GIA's approach is quite "theoretical". Remember that in the GIA system gray is not a hue! This is the key. Thus, it is often ignored. That is why gray stones with a hint of blue, i.e. The Wittelsbach becomes "fancy deep blue". The same holds with green. The gray is ignored but only as a hue, the sum total effect of the gray, i.e. the pumping up of the tone is not.

I may be totally wrong but didn't the GIA class the Wittelsbach originally as fancy deep greyish blue (or something similar) but after the re-cut the grey was dropped?

Yup, this is from Wikipedia because I had to refresh my memory.

its color grade revised from Fancy Deep Grayish Blue, the same grade given by GIA to The Hope, to the more desirable Fancy Deep Blue

http://en.wikipedia.org/wiki/Wittelsbach-Graff_Diamond