AGS fluorescence: negligible… but I see bright blue?

[Sprinkles&Stones]

Hi!

I just got my beautiful WF ACA studs. Of course being a PSer, first thing I do is whip out the loupe and my black light.

I noticed one of the diamonds lights up bright blue under my fluorescence black light. I don’t mind it, but when I checked both my AGS reports I see both of the diamonds are listed as “Fluorescence : Negligible”.

My stud seems to light up to the same level as my other GIA diamonds graded with medium and strong fluorescence.

My question is: how strict is the AGS when grading fluorescence? To me, negligible would be barely visible under black light, not bright blue.

Should I be worried that something is amiss? Is this normal for WF ACA diamonds, or normal for AGS to not match?

 

[Karl_K]

Ags “Fluorescence : Negligible” means less than medium.

Most consumer uv lights will often give a stronger response in the diamond than the official uv light source used to set the grade.

 

[Karl_K]

Also go by what you see by eye, call phone cameras can make faint look like very strong as they have built in processing to enhance dark images.

 

[Sprinkles&Stones]

Thank you @Karl_K ! That makes sense. I learned something new

 

[oldminer]

That amount of a UV reaction is not "Negligible by AGS Standards, I believe. I was told that AGS used Negligible for the least amount of UV fluorescence they could see, not just less than Medium. GIA uses None when there still is Some, which boggles the mind, but uses Faint and Slight before grading Medium and I continue to think AGSL does the same.

Maybe someone will come online and make it clear for me and for you. Possibly the diamonds in the earrings will look fine under normal lighting anyway, but what you are showing is not "negligible", unless AGSL has now decided to mimic the GIA's weird approach to the use of None.

 

[CircularBrilliant]

Here is AGS's explanation of how they grade fluorescence: https://www.americangemsociety.org/ags-laboratories/ags-laboratories-consumer-homepage/fluorescence/

"At AGS Laboratories, we decided to include None, Very Faint, and Faint into one grade, 'Negligible.' Why? Because fluorescence in these small ranges have little impact on how the diamond appears face-up, so our scale has only four grades: Negligible, Medium, Strong, and Very Strong."

 

[oldminer]

Here is AGS's explanation of how they grade fluorescence: https://www.americangemsociety.org/ags-laboratories/ags-laboratories-consumer-homepage/fluorescence/

"At AGS Laboratories, we decided to include None, Very Faint, and Faint into one grade, 'Negligible.' Why? Because fluorescence in these small ranges have little impact on how the diamond appears face-up, so our scale has only four grades: Negligible, Medium, Strong, and Very Strong."

THANKS CB. Always good to learn something new. Much appreciated!!
I don't agree with what they decided, since the amount of fluorescence is quite apparent, but I do understand the the visual effect of less than medium is Negligible. That does make good sense if you look at it that way..

Learning a bit more every day makes up for things one forgets over the years. Adopting this broader grading is something to consider doing myself.

 

[CircularBrilliant]

THANKS CB. Always good to learn something new. Much appreciated!!
I don't agree with what they decided, since the amount of fluorescence is quite apparent, but I do understand the the visual effect of less than medium is Negligible. That does make good sense if you look at it that way..

Learning a bit more every day makes up for things one forgets over the years. Adopting this broader grading is something to consider doing myself.

I was surprised by it too!

 

[Sprinkles&Stones]

That amount of a UV reaction is not "Negligible by AGS Standards, I believe. I was told that AGS used Negligible for the least amount of UV fluorescence they could see, not just less than Medium. GIA uses None when there still is Some, which boggles the mind, but uses Faint and Slight before grading Medium and I continue to think AGSL does the same.

Maybe someone will come online and make it clear for me and for you. Possibly the diamonds in the earrings will look fine under normal lighting anyway, but what you are showing is not "negligible", unless AGSL has now decided to mimic the GIA's weird approach to the use of None.

Thank you for explaining that! I agree, I feel that it’s more than negligible !

 

[Sprinkles&Stones]

Here is AGS's explanation of how they grade fluorescence: https://www.americangemsociety.org/ags-laboratories/ags-laboratories-consumer-homepage/fluorescence/

"At AGS Laboratories, we decided to include None, Very Faint, and Faint into one grade, 'Negligible.' Why? Because fluorescence in these small ranges have little impact on how the diamond appears face-up, so our scale has only four grades: Negligible, Medium, Strong, and Very Strong."

Thank you! I didn’t know that! That is very helpful

 

[Texas Leaguer]

AGSL decided to take a different approach to reporting on fluorescence many years ago, and everything that has been learned about the property in recent years has validated that decision.

First, faint to medium fluorescence has been shown in GIA studies to have virtually zero impact on appearance or performance. Second, trying to slice and dice levels of fluoro in the none-to-faint category is a fools errand, considering the lack of an absolute standard for excitation. And even the same device in the lab can produce different excitation as it ages. Not to mention the plethora of devices now available to consumers that produce widely varying observations.

It is only when fluoro reaches a minimum of medium that there is even potential for positive (whitening) or negative (haziness or diminished contrast) impacts. And even at medium it is debatable whether any impacts can be seen at all by typical observers in typical lighting environments.

It is not until intensity reaches strong and very strong that any effects are likely to be noticed, if they are noticed at all. Therefore, grouping less than medium as 'negligible' is the logically correct approach.

If there is one thing to criticize it is GIA's use of the term 'none' to include diamonds that have 'some' fluorescence!!

Traditionally lab reporting on fluorescence was intended simply as another piece of information to help positively identify the diamond. In recent years the reporting has become intermingled with performance characteristics, which has resulted in consumer confusion and new areas of debate in the trade.

 

[LilAlex]

"...Because fluorescence in these small ranges have little impact on how the diamond appears face-up..."

Funny that they use that rationale when nearly all the single-level distinctions in grading parameters "have little impact on how the diamond appears face-up." Think VVS1 vs VVS2, D vs E, etc.

 

[Sprinkles&Stones]

AGSL decided to take a different approach to reporting on fluorescence many years ago, and everything that has been learned about the property in recent years has validated that decision.

First, faint to medium fluorescence has been shown in GIA studies to have virtually zero impact on appearance or performance. Second, trying to slice and dice levels of fluoro in the none-to-faint category is a fools errand, considering the lack of an absolute standard for excitation. And even the same device in the lab can produce different excitation as it ages. Not to mention the plethora of devices now available to consumers that produce widely varying observations.

It is only when fluoro reaches a minimum of medium that there is even potential for positive (whitening) or negative (haziness or diminished contrast) impacts. And even at medium it is debatable whether any impacts can be seen at all by typical observers in typical lighting environments.

It is not until intensity reaches strong and very strong that any effects are likely to be noticed, if they are noticed at all. Therefore, grouping less than medium as 'negligible' is the logically correct approach.

If there is one thing to criticize it is GIA's use of the term 'none' to include diamonds that have 'some' fluorescence!!

Traditionally lab reporting on fluorescence was intended simply as another piece of information to help positively identify the diamond. In recent years the reporting has become intermingled with performance characteristics, which has resulted in consumer confusion and new areas of debate in the trade.

Thank you Bryan! I just wanted to add that I am a huge Fluor fan! I love my diamonds with fluorescence and think it's super "kitchen kewl" as our friend Karl would say

I was just confused as to what negligible meant when I could see blue. Thanks for chiming in! That makes a lot of sense.
I love my new studs and can't wait to add more ACA's to my collection

 

[Sprinkles&Stones]

Funny that they use that rationale when nearly all the single-level distinctions in grading parameters "have little impact on how the diamond appears face-up." Think VVS1 vs VVS2, D vs E, etc.

That's a really good point.... I never thought of it like that!

 

[yssie]

It really does seem that sometimes the graders just pull fluor assignments out of hats. I’ve seen some in-my-opinion-quite-thoroughly-bizarre fluor grading in my own stones from GIA.

@Sprinkles&Stones For future reference - you can have your vendor check stones in-house before shipping out to you. I always do, I don’t trust the lab report. Almost any vendor will be willing to do that for you in the non-melee sizes! And these particular studs - I can say that this discrepancy would bother me, but I’m not you of course! If it bothers you then talk to your rep and see what they can do, I’m confident WF will make you happy

 

[Sprinkles&Stones]

It really does seem that sometimes the graders just pull fluor assignments out of hats. I’ve seen some in-my-opinion-quite-thoroughly-bizarre fluor grading in my own stones from GIA.

@Sprinkles&Stones For future reference - you can have your vendor check stones in-house before shipping out to you. I always do, I don’t trust the lab report. Almost any vendor will be willing to do that for you in the non-melee sizes! And these particular studs - I can say that this discrepancy would bother me, but I’m not you of course! If it bothers you then talk to your rep and see what they can do, I’m confident WF will make you happy

that's an excellent idea, I didn't think of that before! I naively just assumed that "oh those reports are 100% accurate and include everything I could ever need to know" - haha. Thank you!

I don't mind the fluor, an I feel much better knowing now that fluor gradings seem to be all over the place and subject to the grader's own discretion, more so than other aspects of the grading. I was worried there for a minute!

 

[yssie]

that's an excellent idea, I didn't think of that before! I naively just assumed that "oh those reports are 100% accurate and include everything I could ever need to know" - haha. Thank you!

That’s not an unreasonable assumption! Sadly it’s just not the case…

I don't mind the fluor, an I feel much better knowing now that fluor gradings seem to be all over the place and subject to the grader's own discretion, more so than other aspects of the grading. I was worried there for a minute!

Glad to hear it

 

[nojs]

Excellent info on fluorescence, thank you who have participated! I personally love fluorescence and feel that it should be more valued now that we have so many lab diamonds around (nothing wrong with those per se). Fluorescence in a diamond is a proof of a natural origin, at least for the time being.

 

[Texas Leaguer]

Funny that they use that rationale when nearly all the single-level distinctions in grading parameters "have little impact on how the diamond appears face-up." Think VVS1 vs VVS2, D vs E, etc.

To a large extent the value of natural, Earth-mined diamonds is predicated on rarity. Thus, the grades (at the upper levels especially) are very small increments corresponding to how frequently or how rarely they come out of the ground.

Which is why it makes little sense to grade synthetic diamonds in the same way. Rarity is not a factor for products capable of being mass produced.

 

[max1111]

It seems insane to me that these can both be in the same grade.

 

[Sprinkles&Stones]

It seems insane to me that these can both be in the same grade.

My thoughts too!

 

[Diamond Girl 21]

Using the scale above is what I was taught at GIA. I find it very concerning that diamonds with fluorescence, even minimal, would be graded as having none.

 

[Sprinkles&Stones]

Using the scale above is what I was taught at GIA. I find it very concerning that diamonds with fluorescence, even minimal, would be graded as having none.

I agree! And that both of these diamonds would be I the same grade!

 

[oldminer]

AGS does not grade "None" when there is "Some". They grade Negligible.
GIA grades "None" when there is less than "Faint". This seems a poor choice.
To me and many others, Negligible is the right word to use for none to less than faint. AGS is using Negligible to mean that there is no visible effect below medium which while technically correct, gives rise to the issues raised in the thread. Neither lab is making the best use of words and creating needless confusion.

 

[Diamond Girl 21]

AGS does not grade "None" when there is "Some". They grade Negligible.
GIA grades "None" when there is less than "Faint". This seems a poor choice.
To me and many others, Negligible is the right word to use for none to less than faint. AGS is using Negligible to mean that there is no visible effect below medium which while technically correct, gives rise to the issues raised in the thread. Neither lab is making the best use of words and creating needless confusion.

This helps clarify things, although I don't like the way either lab chooses to grade it. Thank you.

 

[max1111]

AGS does not grade "None" when there is "Some". They grade Negligible.
GIA grades "None" when there is less than "Faint". This seems a poor choice.
To me and many others, Negligible is the right word to use for none to less than faint. AGS is using Negligible to mean that there is no visible effect below medium which while technically correct, gives rise to the issues raised in the thread. Neither lab is making the best use of words and creating needless confusion.

Negligible would be a better word for GIA but what's more problematic is grouping stones that traditionally have at least a 10% spread in price into the same grade. That is not a consumer focussed move.

What's next? VVS1 graded as IF since no-one can see the difference face up.

 

[yssie]

To a large extent the value of natural, Earth-mined diamonds is predicated on rarity. Thus, the grades (at the upper levels especially) are very small increments corresponding to how frequently or how rarely they come out of the ground.

Which is why it makes little sense to grade synthetic diamonds in the same way. Rarity is not a factor for products capable of being mass produced.

At the risk of derailing this thread for half a moment… This is the best, simplest explanation I’ve seen. Thank you

And I completely agree!! There’s just no point in evaluating something that can be mass produced at will using factors that are driven fundamentally by scarcity in nature. The only metrics that matter for lab stones are what can be appreciated with the naked eye.

 

[max1111]

Negligible would be a better word for GIA but what's more problematic is grouping stones that traditionally have at least a 10% spread in price into the same grade. That is not a consumer focussed move.

What's next? VVS2 graded as IF since no-one can see the difference face up.

Correction

 

[Texas Leaguer]

I agree! And that both of these diamonds would be I the same grade!

Here is what GIA says about their None designation:

"A fluorescence description of 'none' represents a range of fluorescence from indiscernible to very faint. Used for identification purposes."

We should not consider fluorescence a "grade" per se. It is an observation that was always intended to simply help identify the stone, in a holistic way together with the other data on a report.

It has come to be regarded by the market as something more like a grade. And that has caused confusion because of the variables involved in the observation of fluorescence, especially outside of the labs. Not to mention what, if any, bearing it has on the appearance of the diamond.

Recent studies have shown that the property is very benign in terms of impacting appearance or performance of the diamond. There are some valid considerations to be explored with strong and very strong, but otherwise whether a diamond has some level of fluorescence it's pretty much a moot point.

There is clearly bias in the marketplace that is irrational, given the facts as we know them today. Just as there is bias on the part of those selling fluorescent diamonds and touting it as a benefit for lower colors. That too is a dubious claim given the science.

 

[Sprinkles&Stones]

Here is what GIA says about their None designation:

"A fluorescence description of 'none' represents a range of fluorescence from indiscernible to very faint. Used for identification purposes."

We should not consider fluorescence a "grade" per se. It is an observation that was always intended to simply help identify the stone, in a holistic way together with the other data on a report.

It has come to be regarded by the market as something more like a grade. And that has caused confusion because of the variables involved in the observation of fluorescence, especially outside of the labs. Not to mention what, if any, bearing it has on the appearance of the diamond.

Recent studies have shown that the property is very benign in terms of impacting appearance or performance of the diamond. There are some valid considerations to be explored with strong and very strong, but otherwise whether a diamond has some level of fluorescence it's pretty much a moot point.

There is clearly bias in the marketplace that is irrational, given the facts as we know them today. Just as there is bias on the part of those selling fluorescent diamonds and touting it as a benefit for lower colors. That too is a dubious claim given the science.

Thanks for explaining that!