florescence on a colorless diamond

[MarineRandy]

I have read many threads regarding florescence and I am unable to draw a conclusion as to wheather this is a good thing or a bad thing on a colorless diamond. Here is the problem, I have found the perfect diamond E color cut: ex poli:ex sym:ex 1.50ct I like everything about this diamond but it says on the cert. that it has strong florescence and I am worried that it might look hazy or have a "milky" appearance. Is this actually true regarding florescence and colorless diamonds ? I have not recieved the diamond yet I am just hoping to get some insight on to this problem.

 

[Deelight]

You would need to ask the vendor selling you the diamond or look at it yourself if you can in sunlight to see if any haziness or oiliness is apparent.

The case for flouro or not is a personal preference some people like some people don''t

 

[rogeshoe57]

Hmm... I got a F 1.37C with Med Fluro and it looks super icey white!

 

[Paul-Antwerp]

The weird thing is that ''the trade'' has grown to dislike fluorescence, while we see here on PS that many consumers love it.

Historically, the trade used to see it as less valuable in the top-colours (say G and better), while it was regarded a bonus and more valuable in lower colours. Probably with new generations coming into the trade, and them learning less by experience and more by focusing on the most expensive stones, many professionals now regard fluorescence as a negative overall.

It is not uncommon to have professionals in our business developing standards that are against the gut-feeling and observations of the consuming public. The way in which most jewelers stress colour and clarity over cut is just another example.

In reality, back to your question, some stones with a grade of strong or very strong fluorescence could indeed have a milky appearance in direct sunlight. The majority however will show you a clear, bright, sparkly ever so slightly bluish tint, that you will probably love.

The percentage of those being milky is very low, but it could be the case. If you have a good vendor, he will not try to sell you that, in fact, he will not have bought it from his supplier. If you have a vendor, however, who wants to whoo you with a very low price, which looks like a fantastic deal, you should be wary.

Live long,

 

[diagem]

Date: 4/19/2008 9:01:59 AM
Author: Paul-Antwerp
The weird thing is that ''the trade'' has grown to dislike fluorescence, while we see here on PS that many consumers love it.

Historically, the trade used to see it as less valuable in the top-colours (say G and better), while it was regarded a bonus and more valuable in lower colours. Probably with new generations coming into the trade, and them learning less by experience and more by focusing on the most expensive stones, many professionals now regard fluorescence as a negative overall.

How historical back do you mean? Not too long ago (30+ years ago)..., strong fluo. in colorless Diamonds was a sought after look/appearance! It was even identified as "Blue-white" Diamonds..., and commanded (sometimes even hefty) premiums!

It is not uncommon to have professionals in our business developing standards that are against the gut-feeling and observations of the consuming public. The way in which most jewelers stress colour and clarity over cut is just another example.

In reality, back to your question, some stones with a grade of strong or very strong fluorescence could indeed have a milky appearance in direct sunlight. The majority however will show you a clear, bright, sparkly ever so slightly bluish tint, that you will probably love.

The percentage of those being milky is very low, but it could be the case. If you have a good vendor, he will not try to sell you that, in fact, he will not have bought it from his supplier. If you have a vendor, however, who wants to whoo you with a very low price, which looks like a fantastic deal, you should be wary.

Live long,

The problem with fluorescence Diamonds started when huge jewelry Corporations like Tiffany & Co etc..., etc..., needed to purchase Diamonds by a system as they purchased Diamonds in huge quantities...

It was a "type" corporate decision to limit their Diamond buyers freedom to purchase Diamonds that possess at a maximum "medium" blue fluo..., and it made sense for a huge Company to work in this fashion as they didnt want to purchase these fluorescence Diamonds based on a stone per stone appearance..., (for example: this Diamond is not milky so its ok..., and that one is a bit milky so its not ok..., type of decisions...)

This decision brought the rest of the high end jewelers to follow suit (wrongfully in my opinion)..., and automatically reject fluorescence Diamonds all together!

A perfect example and answer is listening to our extremely well educated consumer''s here on PS..., for some reason

(a right one if I may add my personal opinion) a lot of them rather prefer the unique positive appearance that comes with the majority of fluorescence Diamonds..., and like many said before..., most fluorescence Diamonds do not appear milky when exposed to different lights!

Think about this..., with the prices of Diamonds shooting up as they are..., it will be sooner than later that these fluorescence Diamonds will even out in demand and price! Its the right time to put your hands on a beautiful fluorescence Diamond (with no negative appearance) as they are still considered a bit less expensive than their counterparts.

Just my opinion!

 

[Paul-Antwerp]

Diagem,

Your comments seem very logical to me. It might well be that the ''corporisation'' of some big companies has been at the source of this illogical trade-situation.

Live long,

 

[kcgunesq]

Date: 4/19/2008 1:07:23 AM
Author:MarineRandy
I have read many threads regarding florescence and I am unable to draw a conclusion as to wheather this is a good thing or a bad thing on a colorless diamond. Here is the problem, I have found the perfect diamond E color cut: ex poli:ex sym:ex 1.50ct I like everything about this diamond but it says on the cert. that it has strong florescence and I am worried that it might look hazy or have a 'milky' appearance. Is this actually true regarding florescence and colorless diamonds ? I have not recieved the diamond yet I am just hoping to get some insight on to this problem.

As you should do anyhow, take your diamond to an independent appraiser as soon as you receive it, who can evaluate whether it is causing any detriment.

Personally, as a consumer, I worked hard to find a diamond (EC F VVS1)for my wife with at least MB flouro. I love it. I only wish that I could have found a SB or VSB in an otherwise suitable diamond.

As a side benefit, if I remember the charts I've seen, an E with SB will probably sell at a discount of about 7-10% compared to a Faint, Neg or none. So you hopefully bought an extra cool diamond at a great price.

ETA: NOTE TO INDUSTRY - I probably would have paid a premium of 5% for MB and as much as 10% for SB or VSB.

 

[WinkHPD]

Date: 4/19/2008 9:36:36 AM
Author: DiaGem

Date: 4/19/2008 9:01:59 AM

Author: Paul-Antwerp

The weird thing is that ''the trade'' has grown to dislike fluorescence, while we see here on PS that many consumers love it.


Historically, the trade used to see it as less valuable in the top-colours (say G and better), while it was regarded a bonus and more valuable in lower colours. Probably with new generations coming into the trade, and them learning less by experience and more by focusing on the most expensive stones, many professionals now regard fluorescence as a negative overall.


How historical back do you mean? Not too long ago (30+ years ago)..., strong fluo. in colorless Diamonds was a sought after look/appearance! It was even identified as ''Blue-white'' Diamonds..., and commanded (sometimes even hefty) premiums!


It is not uncommon to have professionals in our business developing standards that are against the gut-feeling and observations of the consuming public. The way in which most jewelers stress colour and clarity over cut is just another example.


In reality, back to your question, some stones with a grade of strong or very strong fluorescence could indeed have a milky appearance in direct sunlight. The majority however will show you a clear, bright, sparkly ever so slightly bluish tint, that you will probably love.


The percentage of those being milky is very low, but it could be the case. If you have a good vendor, he will not try to sell you that, in fact, he will not have bought it from his supplier. If you have a vendor, however, who wants to whoo you with a very low price, which looks like a fantastic deal, you should be wary.


Live long,

The problem with fluorescence Diamonds started when huge jewelry Corporations like Tiffany & Co etc..., etc..., needed to purchase Diamonds by a system as they purchased Diamonds in huge quantities...


It was a ''type'' corporate decision to limit their Diamond buyers freedom to purchase Diamonds that possess at a maximum ''medium'' blue fluo..., and it made sense for a huge Company to work in this fashion as they didnt want to purchase these fluorescence Diamonds based on a stone per stone appearance..., (for example: this Diamond is not milky so its ok..., and that one is a bit milky so its not ok..., type of decisions...)


This decision brought the rest of the high end jewelers to follow suit (wrongfully in my opinion)..., and automatically reject fluorescence Diamonds all together!


A perfect example and answer is listening to our extremely well educated consumer''s here on PS..., for some reason

(a right one if I may add my personal opinion) a lot of them rather prefer the unique positive appearance that comes with the majority of fluorescence Diamonds..., and like many said before..., most fluorescence Diamonds do not appear milky when exposed to different lights!


Think about this..., with the prices of Diamonds shooting up as they are..., it will be sooner than later that these fluorescence Diamonds will even out in demand and price! Its the right time to put your hands on a beautiful fluorescence Diamond (with no negative appearance) as they are still considered a bit less expensive than their counterparts.

Just my opinion!

Oh no! Just when I am really enjoying my verbal jousts with DiaGem he goes and ruins it all by saying something that I am 100% in agreement with. Now what will I do for fun?

There are threads here, and also somewhere, a video that I made some months ago that shows some fluorescent diamonds versus non fluorescent diamonds and it was clear to see that unless you have an overblue (stone becomes oily or milky in sunlight) that fluorescence adds greatly to the viewing pleasure of most people. Once they have seen it, nine out of ten of my clients tell me they like what they see or that they don''t even see it at all. One out of ten will tell me that that wonderful light blue color in the sunlight bothers them. (Of course, they do not call it wonderful, that''s just me...)

Wink

P.S. DiaGem, I look forward to continuing our ongoing disagreements about almost every thing else...

 

[diagem]

Date: 4/19/2008 1:31:10 PM
Author: Wink

Date: 4/19/2008 9:36:36 AM
Author: DiaGem

Date: 4/19/2008 9:01:59 AM

Author: Paul-Antwerp

The weird thing is that ''the trade'' has grown to dislike fluorescence, while we see here on PS that many consumers love it.


Historically, the trade used to see it as less valuable in the top-colours (say G and better), while it was regarded a bonus and more valuable in lower colours. Probably with new generations coming into the trade, and them learning less by experience and more by focusing on the most expensive stones, many professionals now regard fluorescence as a negative overall.


How historical back do you mean? Not too long ago (30+ years ago)..., strong fluo. in colorless Diamonds was a sought after look/appearance! It was even identified as ''Blue-white'' Diamonds..., and commanded (sometimes even hefty) premiums!


It is not uncommon to have professionals in our business developing standards that are against the gut-feeling and observations of the consuming public. The way in which most jewelers stress colour and clarity over cut is just another example.


In reality, back to your question, some stones with a grade of strong or very strong fluorescence could indeed have a milky appearance in direct sunlight. The majority however will show you a clear, bright, sparkly ever so slightly bluish tint, that you will probably love.


The percentage of those being milky is very low, but it could be the case. If you have a good vendor, he will not try to sell you that, in fact, he will not have bought it from his supplier. If you have a vendor, however, who wants to whoo you with a very low price, which looks like a fantastic deal, you should be wary.


Live long,

The problem with fluorescence Diamonds started when huge jewelry Corporations like Tiffany & Co etc..., etc..., needed to purchase Diamonds by a system as they purchased Diamonds in huge quantities...


It was a ''type'' corporate decision to limit their Diamond buyers freedom to purchase Diamonds that possess at a maximum ''medium'' blue fluo..., and it made sense for a huge Company to work in this fashion as they didnt want to purchase these fluorescence Diamonds based on a stone per stone appearance..., (for example: this Diamond is not milky so its ok..., and that one is a bit milky so its not ok..., type of decisions...)


This decision brought the rest of the high end jewelers to follow suit (wrongfully in my opinion)..., and automatically reject fluorescence Diamonds all together!


A perfect example and answer is listening to our extremely well educated consumer''s here on PS..., for some reason

(a right one if I may add my personal opinion) a lot of them rather prefer the unique positive appearance that comes with the majority of fluorescence Diamonds..., and like many said before..., most fluorescence Diamonds do not appear milky when exposed to different lights!


Think about this..., with the prices of Diamonds shooting up as they are..., it will be sooner than later that these fluorescence Diamonds will even out in demand and price! Its the right time to put your hands on a beautiful fluorescence Diamond (with no negative appearance) as they are still considered a bit less expensive than their counterparts.

Just my opinion!

Oh no! Just when I am really enjoying my verbal jousts with DiaGem he goes and ruins it all by saying something that I am 100% in agreement with. Now what will I do for fun?

There are threads here, and also somewhere, a video that I made some months ago that shows some fluorescent diamonds versus non fluorescent diamonds and it was clear to see that unless you have an overblue (stone becomes oily or milky in sunlight) that fluorescence adds greatly to the viewing pleasure of most people. Once they have seen it, nine out of ten of my clients tell me they like what they see or that they don''t even see it at all. One out of ten will tell me that that wonderful light blue color in the sunlight bothers them. (Of course, they do not call it wonderful, that''s just me...)

Wink

P.S. DiaGem, I look forward to continuing our ongoing disagreements about almost every thing else...

Wink..., what''s wrong with you..., its your fault..., you are/were not supposed to AGREE WITH ME!!!

 

[spike13]

A PS''er just posted pics of her ring that has MB flr. There''s one in the sun that shows what it looks like:
https://www.pricescope.com/community/threads/my-new-ring.83451/

Personally, I think it looks quite pretty.

 

[WinkHPD]

Date: 4/19/2008 1:40:00 PM
Author: DiaGem

Date: 4/19/2008 1:31:10 PM
Author: Wink

Date: 4/19/2008 9:36:36 AM
Author: DiaGem

Date: 4/19/2008 9:01:59 AM

Author: Paul-Antwerp

The weird thing is that ''the trade'' has grown to dislike fluorescence, while we see here on PS that many consumers love it.


Historically, the trade used to see it as less valuable in the top-colours (say G and better), while it was regarded a bonus and more valuable in lower colours. Probably with new generations coming into the trade, and them learning less by experience and more by focusing on the most expensive stones, many professionals now regard fluorescence as a negative overall.


How historical back do you mean? Not too long ago (30+ years ago)..., strong fluo. in colorless Diamonds was a sought after look/appearance! It was even identified as ''Blue-white'' Diamonds..., and commanded (sometimes even hefty) premiums!


It is not uncommon to have professionals in our business developing standards that are against the gut-feeling and observations of the consuming public. The way in which most jewelers stress colour and clarity over cut is just another example.


In reality, back to your question, some stones with a grade of strong or very strong fluorescence could indeed have a milky appearance in direct sunlight. The majority however will show you a clear, bright, sparkly ever so slightly bluish tint, that you will probably love.


The percentage of those being milky is very low, but it could be the case. If you have a good vendor, he will not try to sell you that, in fact, he will not have bought it from his supplier. If you have a vendor, however, who wants to whoo you with a very low price, which looks like a fantastic deal, you should be wary.


Live long,

The problem with fluorescence Diamonds started when huge jewelry Corporations like Tiffany & Co etc..., etc..., needed to purchase Diamonds by a system as they purchased Diamonds in huge quantities...


It was a ''type'' corporate decision to limit their Diamond buyers freedom to purchase Diamonds that possess at a maximum ''medium'' blue fluo..., and it made sense for a huge Company to work in this fashion as they didnt want to purchase these fluorescence Diamonds based on a stone per stone appearance..., (for example: this Diamond is not milky so its ok..., and that one is a bit milky so its not ok..., type of decisions...)


This decision brought the rest of the high end jewelers to follow suit (wrongfully in my opinion)..., and automatically reject fluorescence Diamonds all together!


A perfect example and answer is listening to our extremely well educated consumer''s here on PS..., for some reason

(a right one if I may add my personal opinion) a lot of them rather prefer the unique positive appearance that comes with the majority of fluorescence Diamonds..., and like many said before..., most fluorescence Diamonds do not appear milky when exposed to different lights!


Think about this..., with the prices of Diamonds shooting up as they are..., it will be sooner than later that these fluorescence Diamonds will even out in demand and price! Its the right time to put your hands on a beautiful fluorescence Diamond (with no negative appearance) as they are still considered a bit less expensive than their counterparts.

Just my opinion!

Oh no! Just when I am really enjoying my verbal jousts with DiaGem he goes and ruins it all by saying something that I am 100% in agreement with. Now what will I do for fun?

There are threads here, and also somewhere, a video that I made some months ago that shows some fluorescent diamonds versus non fluorescent diamonds and it was clear to see that unless you have an overblue (stone becomes oily or milky in sunlight) that fluorescence adds greatly to the viewing pleasure of most people. Once they have seen it, nine out of ten of my clients tell me they like what they see or that they don''t even see it at all. One out of ten will tell me that that wonderful light blue color in the sunlight bothers them. (Of course, they do not call it wonderful, that''s just me...)

Wink

P.S. DiaGem, I look forward to continuing our ongoing disagreements about almost every thing else...

Wink..., what''s wrong with you..., its your fault..., you are/were not supposed to AGREE WITH ME!!!

I know, it must be a Saturday thing, I was bitten by a tick this morning, feeling dizzy, where


am



i

(Fade to black)

 

[Garry H (Cut Nut)]

excellent discussion

top marks to you''all

BTW for newbie readers - no well cut diamond looks good in direct sunlight. You can search here and find at least 20 to 50 posts of new diamond owners asking why their beauty looks dark in direct sunlight.
So an oliy appearance in direct sun light is a non issue - maybe 5% of Very Strong Blues will be oily in shaded sunlight - have your back to the sun so your body shades the diamond for testing.

 

[Paul-Antwerp]

Date: 4/19/2008 4:36:28 PM
Author: Garry H (Cut Nut)
excellent discussion

top marks to you''all

BTW for newbie readers - no well cut diamond looks good in direct sunlight. You can search here and find at least 20 to 50 posts of new diamond owners asking why their beauty looks dark in direct sunlight.
So an oliy appearance in direct sun light is a non issue - maybe 5% of Very Strong Blues will be oily in shaded sunlight - have your back to the sun so your body shades the diamond for testing.

Garry, shouldn''t that read: no diamond looks at its best in direct sunlight ?

If I remember correctly what Peter Yantzer last year revealed about the ongoing AGS scintillation studies, he gave us this remark. The probability of observing a scintillation event in direct sunlight (I believe in a well-cut round) is around 3%. I would guess that this probability goes down with cut-quality going down.

And maybe the overabundance of ozone in our summers, compared to the whole in the ozone-layer around your parts of the world also makes a difference. Just guessing. What do you think?

Live long,

 

[WinkHPD]

Date: 4/19/2008 4:36:28 PM
Author: Garry H (Cut Nut)
excellent discussion

top marks to you''all

BTW for newbie readers - no well cut diamond looks good in direct sunlight. You can search here and find at least 20 to 50 posts of new diamond owners asking why their beauty looks dark in direct sunlight.

So an oliy appearance in direct sun light is a non issue - maybe 5% of Very Strong Blues will be oily in shaded sunlight - have your back to the sun so your body shades the diamond for testing.

Hmmm, you must not have any of well cut AGS 0 cut grades handy to look at in the direct sunlight. They may not look their best, but they still look good! Maybe it is a latitude thing?

I take my clients out of doors to look at my diamonds in the shade and in the sunlight, and I get NO complaints about looking dark. I do however have a few people who disregard my advice not to stare at their diamond in the sun and end up with spots dancing in their eyes for a while.

Maybe I can find the copy of the GIA or AGS report that John Quixote sent me last year, I believe the percentage of over blues is much lower than 5%.

Wink


Wink

 

[Ellen]

Since we''re on the subject, and this is such a good thread, I have a question I hope can be answered by the real experts once and for all.

At what level of blue flo does a stone begin to face up whiter/brighter? I always thought (by reading a post or two on here) that it had to be at least strong. But I have read some posters saying that medium will do it. Could someone please enlighten us all on which it is please?

 

[Ellen]

Date: 4/20/2008 12:56:05 PM
Author: Ellen
Since we're on the subject, and this is such a good thread, I have a question I hope can be answered by the real experts once and for all.

At what level of blue flo does a stone begin to face up whiter/brighter? I always thought (by reading a post or two on here) that it had to be at least strong. But I have read some posters saying that medium will do it. Could someone please enlighten us all on which it is please?

Anybody??

 

[Paul-Antwerp]

Date: 4/20/2008 12:56:05 PM
Author: Ellen
Since we''re on the subject, and this is such a good thread, I have a question I hope can be answered by the real experts once and for all.

At what level of blue flo does a stone begin to face up whiter/brighter? I always thought (by reading a post or two on here) that it had to be at least strong. But I have read some posters saying that medium will do it. Could someone please enlighten us all on which it is please?

The problem is that we just do not check this regularly ourselves. And then the question is whether the stone facing up whiter is a result of the cut or of the fluorescence, or of both.

If I check Rapaport however, he publishes a monthly chart in which fluorescence (starting from Medium) carries a price-premium for stones, starting from I-colour down.

Live long,

 

[Ellen]

Date: 4/21/2008 8:23:58 AM
Author: Paul-Antwerp

The problem is that we just do not check this regularly ourselves. And then the question is whether the stone facing up whiter is a result of the cut or of the fluorescence, or of both.

If I check Rapaport however, he publishes a monthly chart in which fluorescence (starting from Medium) carries a price-premium for stones, starting from I-colour down.

Live long,

Maybe I should have added, in ideal cut stones, as that was what I was thinking of when I asked. But thanks for the info Paul!

 

[diagem]

Date: 4/21/2008 8:23:58 AM
Author: Paul-Antwerp

Date: 4/20/2008 12:56:05 PM
Author: Ellen
Since we''re on the subject, and this is such a good thread, I have a question I hope can be answered by the real experts once and for all.

At what level of blue flo does a stone begin to face up whiter/brighter? I always thought (by reading a post or two on here) that it had to be at least strong. But I have read some posters saying that medium will do it. Could someone please enlighten us all on which it is please?

The problem is that we just do not check this regularly ourselves. And then the question is whether the stone facing up whiter is a result of the cut or of the fluorescence, or of both.

If I check Rapaport however, he publishes a monthly chart in which fluorescence (starting from Medium) carries a price-premium for stones, starting from I-colour down.

Live long,

Ellen, here are just some reasons why its hard to answer your question

It depends on who calls the grade and if it is called accurately!
It also depends on the transparency of the Diamond material itself and if the fluorescence is evenly spread through out the body of the Diamonds or is located in specific zones.

And not to mentions Paul comment on who is the credit due..., the cutter or mother nature?

Too many factors which are based on a stone per stone basis!

The Rapaport guide for fluorescence Diamonds has stayed the same since I remember it. And is based on value according to a standard market view!
He automatically undervalues "all" the high colored Diamonds with fluorescence which I think is non-professional all together!

 

[Ellen]

DiaGem, thanks. I can see there are more variables that I had considered. I was just hoping to get some kind of guidance for posters when they present a possible stone with say med. and J color, and ask if that''s going to help it. I thought asking might help me out, but I see it''s not that simple.

So, should this question arise (in ideal cut stones, I and lower), would it be accurate to say, it''s possible with med., but not in fact a certainty? Or would that even go for med. to very strong flo? And let''s assume these are GIA and AGS stones.

 

[diagem]

Date: 4/21/2008 8:51:12 AM
Author: Ellen
DiaGem, thanks. I can see there are more variables that I had considered. I was just hoping to get some kind of guidance for posters when they present a possible stone with say med. and J color, and ask if that''s going to help it. I thought asking might help me out, but I see it''s not that simple.

So, should this question arise (in ideal cut stones, I and lower), would it be accurate to say, it''s possible with med., but not in fact a certainty? Or would that even go for med. to very strong flo? And let''s assume these are GIA and AGS stones.

Ellen..., its kinda like fancy shape appearance based on numbers..., you can really visualize the appearance when you see the stone with YOUR eyes...

Some J colored Diamonds with faint will appear whiter than a J with Med and visa~versa!
Easy to speculate as it would make perfect sense that a J with med. fluo will make the appearance look whiter..., but no way is it for certain!

 

[Ellen]

Date: 4/19/2008 4:36:28 PM
Author: Garry H (Cut Nut)
excellent discussion

top marks to you''all

BTW for newbie readers - no well cut diamond looks good in direct sunlight. You can search here and find at least 20 to 50 posts of new diamond owners asking why their beauty looks dark in direct sunlight.
So an oliy appearance in direct sun light is a non issue - maybe 5% of Very Strong Blues will be oily in shaded sunlight - have your back to the sun so your body shades the diamond for testing.

I beg to differ sir. I took this yesterday while sitting in the sun on the patio, after thinking about you saying this. Granted, they do go dark, but they also do this.

 

[Ellen]

Date: 4/21/2008 8:58:48 AM
Author: DiaGem

Ellen..., its kinda like fancy shape appearance based on numbers..., you can really visualize the appearance when you see the stone with YOUR eyes...

Some J colored Diamonds with faint will appear whiter than a J with Med and visa~versa!
Easy to speculate as it would make perfect sense that a J with med. fluo will make the appearance look whiter..., but no way is it for certain!

Ok, I will just avoid the flo questions.

 

[WinkHPD]

Date: 4/21/2008 8:35:19 AM
Author: DiaGem

Date: 4/21/2008 8:23:58 AM

Author: Paul-Antwerp

Date: 4/20/2008 12:56:05 PM

Author: Ellen

Since we''re on the subject, and this is such a good thread, I have a question I hope can be answered by the real experts once and for all.


At what level of blue flo does a stone begin to face up whiter/brighter? I always thought (by reading a post or two on here) that it had to be at least strong. But I have read some posters saying that medium will do it. Could someone please enlighten us all on which it is please?

The problem is that we just do not check this regularly ourselves. And then the question is whether the stone facing up whiter is a result of the cut or of the fluorescence, or of both.


If I check Rapaport however, he publishes a monthly chart in which fluorescence (starting from Medium) carries a price-premium for stones, starting from I-colour down.


Live long,

Ellen, here are just some reasons why its hard to answer your question


It depends on who calls the grade and if it is called accurately!

It also depends on the transparency of the Diamond material itself and if the fluorescence is evenly spread through out the body of the Diamonds or is located in specific zones.


And not to mentions Paul comment on who is the credit due..., the cutter or mother nature?


Too many factors which are based on a stone per stone basis!


The Rapaport guide for fluorescence Diamonds has stayed the same since I remember it. And is based on value according to a standard market view!

He automatically undervalues ''all'' the high colored Diamonds with fluorescence which I think is non-professional all together!

This has got to stop!

You are ruining everything. What will our fans think when they see us agreeing lebenty seben times in just three or four days. Will they come to our contests just to see us hug and tip a beer together? I think NOT!.

Sigh.

Still, I must wholeheartedly and loudly declare my complete and unequivocal support for your statement. Some of the most beautiful diamonds I have ever seen have strong or very strong blue on their papers, and rarely, some of the ugliest.

Each stone must be judged on its own merits, and here sadly, is one area that the paper does not help us since no comment is made as to the affect the fluorescence has on the appearance of the stone. So sad, and really, so easily doable.

Now please, for the sake of the children, say something mean about my passion for AGS 0 cutting.

Wink

P.S. All kidding aside, your comment is brilliant!

 

[WinkHPD]

I vaguely remembered getting this from John Quixote and saving it someplace a year or so ago. GIA did a study that is listed here:

http://lgdl.gia.edu/pdfs/w97_fluoresce.pdf

Here are a couple of exerpts.

"In the table-up position (as is commonly encountered in jewelry), diamonds described as strongly or very strongly fluorescent were, on average, reported as having a better color appearance than less fluorescent stones. In this study, blue fluorescence was found to have even less effect on transparency. These observations confirm GIA GTL’s experience grading millions of diamonds over the decades... ...The present study also challenges the trade perception that fluorescence usually has a negative effect on better-color diamonds. Our results show that the diamond industry would be better served by considering each individual diamond on its own visual merits."

"For the experienced observers, we found that, in
general, the strength of fluorescence had no widely
perceptible effect on the color appearance of diamonds
viewed table-down (as is typical in laboratory
and trade grading). In the table-up position (as is
commonly encountered in jewelry), diamonds
described as strongly or very strongly fluorescent
were, on average, reported as having a better color
appearance than less fluorescent stones. In this
study, blue fluorescence was found to have even
less effect on transparency. These observations confirm
GIA GTL’s experience grading millions of diamonds
over the decades."

Wink