High and low end colors

[Pecel]

Is it true that experts in diamond grading can 'see' a difference in color within one grade? In other words, can they differentiate for example 'low end H' - closer o I, and "high end H' - closer to G? Does one category of color grade always and in every expert eyes' look the same? What about D color? Is there something like D+, plain D and D-almost-E?

 

[kenny]

When diamonds are set the color grades are much harder to differentiate.

When diamonds are loose, side by side, up side down, viewed in the correct region at the correct angle, against a white background, under optimized light, the differences are far easier to make out.

 

[kenny]

When diamonds are set the color grades are much harder to differentiate.

When diamonds are loose, side by side, up side down, viewed in the correct region at the correct angle, against a white background, under optimized light, the differences are far easier to make out.

 

[Dreamer_D]

More colorless grades have a smaller range within the grde I have read. As the diamond gets more tinted, the range of tints of stones that can fall into the grade becomes broader. Seems to me that there is about a one color grade "margin of error" anyways with most diamond grades, even with labs like GIA and AGS. Color differences between grades are *very* subtle. Opinions can vary. As such, one person might say "D" and another "E" and the end grade just depends a little on which grader got assigned the stone that day.

 

[Pecel]

Ok, I do understand that much in color grading depends on personal 'issues'. But my question is, is it objectively possible to say that within one grade there are differences in color? In other words, are there in reality better, whiter and 'icer' D's and "warmer', less 'icy" D's which all are graded as D color, regardless the the human factor, but still observable?

 

[slg47]

Ok, I do understand that much in color grading depends on personal 'issues'. But my question is, is it objectively possible to say that within one grade there are differences in color? In other words, are there in reality better, whiter and 'icer' D's and "warmer', less 'icy" D's which all are graded as D color, regardless the the human factor, but still observable?

I doubt this would be observable in a D graded by a reputable lab.

 

[diagem]

D's are supposed to be pure and colorless. But I must admit that I have witnessed a range in the GIA grading on D's.
AGS on the other hand is much tougher and getting a D is no easy task.

My opinion of course.

Type IIa's are by all means non-observable.

 

[Pecel]

But I must admit that I have witnessed a range in the GIA grading on D's.

And this is precisely what I'm asking. Would you qualify any of those lower end D's as E color? Or were they just D color diamonds, less "D-ish" than some others you saw, but still D? I wonder if you have ever found a rocky specimen which color exceeded every other D range diamond you had stumbled on?

Topic doesn't seem to be very interesting for most Pricescopers, but for me is quite intriguing. At least as a theoretical hipotesis

 

[denverappraiser]

Every color grade represents a range and the ranges are quite tight. It's done by experts comparing the subject stone to others under controled lighting conditons. This doesn't even create unanimous agreement even among graders at the same time and in the same lab. If 2 out of 3 graders at GIA call it a D, it's a D and the outlier opinion is discarded. They aren't averaged. Trying to narrow that down to a sub-category of D is out of the question. There are already too many sub-categories.

 

[diamondseeker2006]

The color I is where I have been able to see a difference. Some are quite near colorless, and others I can easily see a tint from the side. I can't imagine being able to see a difference between D and E with the eyes without having it next to another stone in a grading set up.