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I know we're sick of debating FLUORESCENCE but.....

......I have a concern.

I've read a great deal about fluorescence, read a great number of threads, have seen the pictures. I didn't feel I would mind fluorescence in a diamond & it would make my diamond a little more "unique." So I started specifically searching for these diamonds because as I have understood it to be:

- Only 2% of diamonds in the world will have a milky/hazy/oily appearance from VSB fluor based on the GIA study.
- May possibly help a lower color stone (ie. I/J) face up white in some lighting conditions
- the cool glow stick effect in clubs ;))
- Negative connotation due to the scams in the 70's and misconceptions of outdoor appearance
- Can have a bluish/purplish hue outdoors in direct sunlight, but will NOT affect a diamond's performance (diamonds turn dark in direct sunlight any with or without fluor.)
- each diamond with fluor. must be judged individually, on their own merits.

So, I was all for it. But then I read this Journal article on PS & this came up: As posted by Garry in this thread https://www.pricescope.com/community/threads/blue-fluorescence-in-diamonds.120497/page-4


Back to one of the main themes of the article - here is a comment from Tom Tashi as a Letter to the Editor regarding over grading D-Z diamonds by GIA
http://www.gia.edu/research-resources/gems-gemology/issues/summer2009-contents/SU09LT2.pdf

Tom is a very considered and careful Gemologist - those who know him - know that his opinions carry weight.
Here is one paragraph from his letter:

"I was shocked when I first discovered in 1995, by
shielding the Verilux lamps in the GIA DiamondLite with
a clear Makrolon plastic film (which acts as a UV filter),
that stones with very strong blue fluorescence could
appear three or four letter grades lower in color. Similarly,
after sharing my findings and offering others some
Makrolon film for their own experiments, several of my
colleagues and former associates were as shocked as I was
to see these dramatic color shifts in strongly fluorescent
diamonds. I believe this to be a very significant issue in
the accurate color grading of D-to-Z diamonds, and I cannot
accept GIA’s recommendation for their standard viewing
environment."

It seems that although strong fluor. may be a plus for the consumers (mainly the 'non-experts') to have a "J" stone face up 'whiter' due, it may also be "fooling" GIA graders in their labs as well??? Leading to inaccurate color grading of a stone in lower colors?
This concerns me greatly. It seems almost akin to having an EGL graded stone where one may think they're buying one color & actually receiving a color grade much lower.

This has made me pause with my quest to find a stone with fluor. I wouldn't mind it as much if I was searching for an E or F stone; however, in looking for I or even J stones, it can make a big difference.

I did a search & this was briefly discussed in this thread as well (great thread btw) https://www.pricescope.com/forum/ro...ars-clubs-t145168-120.html?hilit=fluorescence where Garry mentioned his methods of minimizing UV light when he grades; however, how am I to know this has been resolved in the GIA labs or any other grading labs for that matter?
 

diamondseeker2006

Super_Ideal_Rock
Premium
Joined
Jan 11, 2006
Messages
58,342
Twinkle, it looks like most of the vendors and appraisers are taking the weekend off, so maybe some will reply to this tomorrow!
 

tyty333

Super_Ideal_Rock
Premium
Joined
Dec 17, 2008
Messages
25,387
You must be an engineer...all teasing aside, I have to say if its good enough for GIA then its good enough for me.

I think for you...you need to order the stone then have it sent to you. Live with it for a few days and decide if you
really love the flour or its not what you had in mind. *I* cant think of any one on PS that has gotten a stone with
blue flour and returned it because they didnt like the flour. Most people are pretty thrilled with the color and the
blue effect flour has in sunlight.

I know nobody wants to pay for an I/J stone when its really a grade or 2 lower. I think if you could have the stone
sent to you then maybe compare it with some other well cut stones in the same color (GIA/AGS0) that might help.
I know this might not be that easy though. Jareds has their Peerless line that could be used for comparison.

You could also work with GOG. They do videos. You could have them bring a stone in with flour and have them
video it with a well cut stone of the same color.

Honestly, if its bothering you, maybe you should go with a non-flour stone. I personally think you should give one
a try though.
 

CaprineSun

Brilliant_Rock
Joined
Sep 30, 2010
Messages
579
tyty333|1301913945|2887282 said:
You must be an engineer...all teasing aside, I have to say if its good enough for GIA then its good enough for me.

I think for you...you need to order the stone then have it sent to you. Live with it for a few days and decide if you
really love the flour or its not what you had in mind. *I* cant think of any one on PS that has gotten a stone with
blue flour and returned it because they didnt like the flour. Most people are pretty thrilled with the color and the
blue effect flour has in sunlight.

I know nobody wants to pay for an I/J stone when its really a grade or 2 lower. I think if you could have the stone
sent to you then maybe compare it with some other well cut stones in the same color (GIA/AGS0) that might help.
I know this might not be that easy though. Jareds has their Peerless line that could be used for comparison.

You could also work with GOG. They do videos. You could have them bring a stone in with flour and have them
video it with a well cut stone of the same color.

Honestly, if its bothering you, maybe you should go with a non-flour stone. I personally think you should give one
a try though.

LOL. No not an engineer. lol :lol:

I have no issues with the actual fluor. at all. I think it's cool. It is the possible effect that it may make a stone look whiter than it should while being graded that concerns me.
But I don't see this issue far off from the very reason EGL stones have a negative rep around here. You pay for one thing but may be getting another. I mean, if a gemologist, who Garry spoke highly of is saying

"....that stones with very strong blue fluorescence could
appear three or four letter grades lower in color. .......I believe this to be a very significant issue in the accurate color grading of D-to-Z diamonds, and I cannot accept GIA’s recommendation for their standard viewing environment."

How can that not raise concern? I'm not trying to be picky if that's the way it comes off. I'm genuinely interested, but I guess no one else seems to. *shrug*

Thanks for the advice & taking the time to respond. :))
 

slg47

Ideal_Rock
Joined
Apr 4, 2010
Messages
9,667
I think the lighting in which grading is done has a UV filter so as to not cause 'inflation' of color grades of stones with fluor.
 

Sheherizaad

Shiny_Rock
Joined
Feb 7, 2011
Messages
244
The whole GIA "report card" process is in my opinion subjective. Yes they do have standards and yes they have the best tools to conform within those standards, but at the end of the day, it's a bunch of people with a lot of experience coming to an agreement on it's overall grades. So while I have confidence that something is not going to go from a D to an G, I think there's some leeway in regard to those "in-between's" (i.e. a D to an E, Excellent vs Ideal cut, VS2 to VS1, etc). I'm sure their principle is to go conservative and that plays a part (which is fine in and of itself).

So when I hear talk of flourescence, I take that into consideration. When my appraiser looked at my stone, he thought it was one color grade better than what it really was due to the flourescence (I know some people on PS will disagree). He compared it to base diamonds that were GIA certified as solid grades (i.e. bonafide D's, E's, F's, G's, etc) and under a bunch of different lighting scenarios. Now, granted, maybe I was just lucky and my stone is super freakishly weird and tripped them up, but he has 20 years experience and my jeweler is actually a gemologist with 15 years under his belt. But I'm happy with their assessments (as well as a GIA certificate of course) in that the flourescence is a BENEFIT when it comes to a warmer color. In my setting it's ridiculously white and only in the sunlight did I see hints of blue (which again, I like).
 
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