Type IIa diamond w/ fluorescence (question)

[stesy]

Hello everyone,

I purchased a diamond earlier this year with an AGS certificate. It is a 1.24ct D colored IF type IIa diamond.

I told the vendor that I would like it to have no fluorescence and the AGS certificate shows "negligible". When I showed the certificate to a family friend, they told me they had never heard of AGS which prompted me to obtain a certification by GIA. GIA returned nearly identical results as the AGS certificate but the fluorescence was deemed "faint".

My question for my fellow forum members is if it is characteristic for type IIa diamonds to show some fluorescence. I looked around and was told that negligible fluorescence from the AGS could mean none, very faint, or faint. Does this mean that in daylight and room light, it would be impossible to see the difference between two identical diamonds differing only in fluorescence (faint vs none)?

Thank you,
Stephen

 

[musicloveranthony]

You will not see it

 

[musicloveranthony]

I'm curious of the vendor, because that might be the nicest cut I've seen. Jann Paul?

 

[ringo865]

you will never see faint fluorescence in normal indoor lighting, probably would not even see it in sunlight. You would see “something” under black light, but “faint” is just that: “faint”

 

[lovedogs]

Agreed, you won't see any difference IRL

 

[crbl999]

I'm curious of the vendor, because that might be the nicest cut I've seen. Jann Paul?

I agree. Super nice stone! That's Jann Paul's logo on the images.

 

[musicloveranthony]

I agree. Super nice stone! That's Jann Paul's logo on the images.

Ah, good eye! Yeah, that's a magnificent diamond. Now I feel like I need to visit Singapore

 

[stesy]

I'm curious of the vendor, because that might be the nicest cut I've seen. Jann Paul?

Hi Anthony, yes it’s JannPaul! I, too, thought it was one of the nicer cuts even among the super ideal vendors. I’m from California and they were able to ship it to me with no problems.

 

[stesy]

you will never see faint fluorescence in normal indoor lighting, probably would not even see it in sunlight. You would see “something” under black light, but “faint” is just that: “faint”

Thank you for the clarification and reassurance

 

[Garry H (Cut Nut)]

In a few years time you may well be kicking yourself for not buying a blue white type II diamond. Especially if this is for investment.
AGS Negligible goes to GIA's faint/medium border.
High clarity diamonds only benefit from fluorescence since there are no inclusions that can cause milkyness.

 

[stesy]

In a few years time you may well be kicking yourself for not buying a blue white type II diamond. Especially if this is for investment.
AGS Negligible goes to GIA's faint/medium border.
High clarity diamonds only benefit from fluorescence since there are no inclusions that can cause milkyness.

Thank you for your reply. Would you be so kind to explain how fluorescence benefits a high clarity diamond? Additionally, do you know if fluorescence is common in type IIa diamonds? Thank you

 

[Garry H (Cut Nut)]

Thank you for your reply. Would you be so kind to explain how fluorescence benefits a high clarity diamond? Additionally, do you know if fluorescence is common in type IIa diamonds? Thank you

I have seen stats but no memory of which article.
The numbers do differe and I think less common than type i - but type IIb with boron and blue often fluoresce red.

 

[Diamond Girl 21]

In a few years time you may well be kicking yourself for not buying a blue white type II diamond. Especially if this is for investment.
AGS Negligible goes to GIA's faint/medium border.
High clarity diamonds only benefit from fluorescence since there are no inclusions that can cause milkyness.

Is there an issue with a D color diamond with fluorescence being considered a discounted stone, even if lovely to look upon?

 

[Diamond_Enthusiast]

AGS Negligible goes to GIA's faint/medium border.

I was surprised and this is consistent with what I noticed with my AGS Negligible D color diamond!

Ordered that diamond from BGD (signature H&A line, not their Blue range) and it actually looks only a little less fluor than my AGS Strong Blue fluor F from BGD's Blue range!

Personally I like fluor even in high colors (those without transparency issues). They somehow look extra crisp to my eyes.

 

[Garry H (Cut Nut)]

Is there an issue with a D color diamond with fluorescence being considered a discounted stone, even if lovely to look upon?

Not for me - give me a strong blue D E or F any day!
And I live in Australia and spend max time outdoors

 

[Garry H (Cut Nut)]

I was surprised and this is consistent with what I noticed with my AGS Negligible D color diamond!

Ordered that diamond from BGD (signature H&A line, not their Blue range) and it actually looks only a little less fluor than my AGS Strong Blue fluor F from BGD's Blue range!

Personally I like fluor even in high colors (those without transparency issues). They somehow look extra crisp to my eyes.

The blue is additive and so makes the diamond literally brighter. Measurably so.

 

[Texas Leaguer]

My question for my fellow forum members is if it is characteristic for type IIa diamonds to show some fluorescence.

@stesy ,
Yes it is a bit unusual as type IIa diamonds are almost completely devoid of nitrogen which is the cause of most blue fluorescence - the most common type of fluorescence.

Because it is faint, no color is stated on the report as is standard. But it could be that the stone is fluorescing a color other than blue due to some atomic trace element or anomoly in the carbon lattice not related to nitrogen.

If you are interested, you might have your vendor inquire with the labs and see if there are any grading notes on what color was observed.

Congratulations on a super rare gem!

 

[Texas Leaguer]

The blue is additive and so makes the diamond literally brighter. Measurably so.

Would you care to elaborate Garry?

 

[Garry H (Cut Nut)]

Would you care to elaborate Garry?

When UV energy goes into a blue fluorescent diamond a large portion of that energy is emitted as energy in the visible light spectrum as a range of emissions from violet to indigo blue.
As a result the diamond is literally and measurably brighter. This is a fact known to true believers and explains why we prefer strong blue fluorescent diamonds.

In addition if there is any yellowish of course blue being the complimentary color - the diamond appears whiter.
Contrary to Michael Cowing's mistaken study based on his wrong choice of UV measuring instrument (which did not measure the UV in the both the visible violet and the near visible range that contributes the most to N3 blue fluorescence) and his inability to note that the UV that causes fluorescence passes through all windows - in most bright lightings there will be some whitening and brightening effect.

A personal choice is to also prefer blue white diamonds. Diamonds that appear icy bluish white sometimes. I have an F Strong Blue 3.15ct (it was Drena's) that many non expert customers have sworn appears whiter than non D colored diamonds.
I am sure you have seen this several times Bryan? This is visible 405nm cheap LED light. The strongest effect is with around 390, not the 365nm which has mistakenly been used to judge the N3 effect. That standard was used because it was available with old fashioned mercury vapour tubes. and employed for gem ID. It was used because it was there. It was always a mistake and led to so many wrong conclusions.
But you know I have been saying this stuff for more than a decade - I do get a bit annoyed that I have to keep saying it - please listen and do your own research or go back and read the stuff I wrote in in Cowings post.

Here is a simple proof of part one:

 

[diagem]

When UV energy goes into a blue fluorescent diamond a large portion of that energy is emitted as energy in the visible light spectrum as a range of emissions from violet to indigo blue.
As a result the diamond is literally and measurably brighter. This is a fact known to true believers and explains why we prefer strong blue fluorescent diamonds.

In addition if there is any yellowish of course blue being the complimentary color - the diamond appears whiter.
Contrary to Michael Cowing's mistaken study based on his wrong choice of UV measuring instrument (which did not measure the UV in the both the visible violet and the near visible range that contributes the most to N3 blue fluorescence) and his inability to note that the UV that causes fluorescence passes through all windows - in most bright lightings there will be some whitening and brightening effect.

A personal choice is to also prefer blue white diamonds. Diamonds that appear icy bluish white sometimes. I have an F Strong Blue 3.15ct (it was Drena's) that many non expert customers have sworn appears whiter than non D colored diamonds.
I am sure you have seen this several times Bryan? This is visible 405nm cheap LED light. The strongest effect is with around 390, not the 365nm which has mistakenly been used to judge the N3 effect. That standard was used because it was available with old fashioned mercury vapour tubes. and employed for gem ID. It was used because it was there. It was always a mistake and led to so many wrong conclusions.
But you know I have been saying this stuff for more than a decade - I do get a bit annoyed that I have to keep saying it - please listen and do your own research or go back and read the stuff I wrote in in Cowings post.

Here is a simple proof of part one:

I didnt conduct any scientific testing on this but completely agree with Garry...

I do prefer my D colored diamonds to carry at least strong fluorescence (excluding yellow) just because they appear crispier and glowing (as opposed to Garry's brighter claim) to me..., just a visual that for most of diamonds history would command premiums which I completely identify with.

I suppose the great debate is usually considering round brilliants (the standard)..., but I truly find the fluorescence effect uniquely different between the modern RB's or other fancy shapes (splintery visuals) vs, other and usually older (blocky visuals) faceting styles.

And as Garry mentioned...., inclusions will definitely affect fluorescence in a negative manner. After all, internal clouds are usually based on microscopic groupings of inclusions, the denser the cloudier.

 

[Karl_K]

I love strong fluorescence but as long as the labs use light for grading without total uv blocking including 400nm in place the discount should stay.
I will even take strong yellow on tinted or yellow colored diamonds.

faint isn't going to be enough to move a grade so its a non-issue for me.

 

[Garry H (Cut Nut)]

I didnt conduct any scientific testing on this but completely agree with Garry...

I do prefer my D colored diamonds to carry at least strong fluorescence (excluding yellow) just because they appear crispier and glowing (as opposed to Garry's brighter claim) to me..., just a visual that for most of diamonds history would command premiums which I completely identify with.

I suppose the great debate is usually considering round brilliants (the standard)..., but I truly find the fluorescence effect uniquely different between the modern RB's or other fancy shapes (splintery visuals) vs, other and usually older (blocky visuals) faceting styles.

And as Garry mentioned...., inclusions will definitely affect fluorescence in a negative manner. After all, internal clouds are usually based on microscopic groupings of inclusions, the denser the cloudier.

Clouds and Internal graining Yoram.
And this is from earlier this year but as yet un published.
I took the images from Cutwise.com - strong blue fluorescent stone - there are plenty of other examples there.
The numbers are from paint from the same spots


Yun Luo found similar results but she quantified using a different metric.

Measurement and Characterization of the Effects of Blue Fluorescence on Diamond Appearance | Gems & Gemology

Using customized, image-based measurement systems to quantify the effect of fluorescence on the color, brightness, and transparency of gem diamonds viewed in both face-up and table-down orientations.

www.gia.edu

 

[Garry H (Cut Nut)]

I love strong fluorescence but as long as the labs use light for grading without total uv blocking including 400nm in place the discount should stay.
I will even take strong yellow on tinted or yellow colored diamonds.

faint isn't going to be enough to move a grade so its a non-issue for me.

What discount would you agree with and for which stones?
Hazyness discounts for higher clarity stones are simply dumb Karl - it should be a bigger discount for lower clarity.
Color discounts grew not because of anything other than consumers believing the same stuff and anti vaxxers on social media and internet misnformation.

1n 1993 after the Korean affair which started the rap discount list:


Today for faint medium and strong - 2.5 times the discount for top color and clarity:


So what discount is correct Karl.
Do you see that there is no logic, just a buying opportunity.

And as I have been saying for a very long time - if there is enough light to be able to identify a few grades in color then you will see a better color in a stong blue than the lab gave the stone.

 

[Texas Leaguer]

Garry,
Thank you for linking the new GIA study. I had not seen it. There is a lot to chew on there!

I need to re-read it (probably multiple times!) but a couple of things are immediately notable. One, as I have speculated in past discussions that haziness in most diamonds is caused by light scattering micro inclusions, independent of fluorescence. But that fluorescence magnifies the problem. This study confirms that suspicion. (It has been my experience that a high percentage strongly fluorescent diamonds are accompanied by twinning wisps and graining which would fall into the category light scattering inclusions). Secondly, I found it interesting that their approach to measuring transparency is by measuring contrast. Since transparency is a significant issue across diamond grades for both fluorescent and non-fluorescent diamonds, the fact that GIA is contemplating adding a transparency metric to future grading reports is welcome news. I have been advocating for that for years.

I will have additional observations after I have a chance to study the article more.

Thanks again for posting.

 

[Texas Leaguer]

btw
I thought this was an odd turn of phrase (in bold):

Fluorescence in diamond is a subject that has generated lively discussion in the trade for decades. It is believed that diamonds with D to F color grades (i.e., colorless), which do not possess enough color to offset the presence of fluorescence,

 

[Karl_K]

What discount would you agree with and for which stones?
Hazyness discounts for higher clarity stones are simply dumb Karl - it should be a bigger discount for lower clarity.
Color discounts grew not because of anything other than consumers believing the same stuff and anti vaxxers on social media and internet misnformation.

1n 1993 after the Korean affair which started the rap discount list:


Today for faint medium and strong - 2.5 times the discount for top color and clarity:


So what discount is correct Karl.
Do you see that there is no logic, just a buying opportunity.

And as I have been saying for a very long time - if there is enough light to be able to identify a few grades in color then you will see a better color in a stong blue than the lab gave the stone.

We are talking about apples and oranges.
Yes hazy discounts should be based on clarity not florescence.
However, the color grade or non-fancy diamonds is the material color not the face up color.
Uv in the grading lighting can interfere with getting an accurate material color grade in highly uv reactive stones.
That uncertainty deserves a discount.
Even gia acknowledges that there is an uncertainty and they just dismiss it based on trade tradition.

 

[Garry H (Cut Nut)]

btw
I thought this was an odd turn of phrase (in bold):

Fluorescence in diamond is a subject that has generated lively discussion in the trade for decades. It is believed that diamonds with D to F color grades (i.e., colorless), which do not possess enough color to offset the presence of fluorescence,

There was more than one author. I have heard Yun Luo on two webinars and it is not likely her contribution.

 

[Garry H (Cut Nut)]

We are talking about apples and oranges.
Yes hazy discounts should be based on clarity not florescence.
However, the color grade or non-fancy diamonds is the material color not the face up color.
Uv in the grading lighting can interfere with getting an accurate material color grade in highly uv reactive stones.
That uncertainty deserves a discount.
Even gia acknowledges that there is an uncertainty and they just dismiss it based on trade tradition.

There are about a dozen historical mistakes in how labs grade diamonds.
Since digital is now possible there is no reason to mislead consumers any longer. All diamonds should be graded for face up colour.

 

[diagem]

There are about a dozen historical mistakes in how labs grade diamonds.
Since digital is now possible there is no reason to mislead consumers any longer. All diamonds should be graded for face up colour.

...and that light is not coming from above (the girdle) only...

 

[Garry H (Cut Nut)]

...and that light is not coming from above (the girdle) only...

The way fancy colored diamonds are graded.
It is not fair that a consumer who wants a colorless 1ct cushion and reads online that I will be safe - and they end up owning a crushed ice cushion facing up L color.