Another Fluorescence ques....in bars/clubs

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Post by Isabelle » June 22nd, 2010, 3:49 am
Date: 6/22/2010 9:03:56 AM
Author: Wink
Date: 6/21/2010 7:54:47 PM

Author: Isabelle

Not all diamond experts are on PS though Dreamer. :-) I''m not an expert. I''m not in the trade. But I''ve read literature that says strong blue fluor negatively impacts a diamond''s appearance. I restate that I accept and believe there are diamonds with strong fluor that look great. Maybe some day the presence of strong fluor won''t hurt a diamond''s value on the market, as Stone suggested. But it has for the last 40 years so it''s out there. And there are experts who say it does matter.



Small quibble, more like 32 - 34 years. We were still selling VSB diamonds at a premium in 1975, it was somewhat later, in the late 70''s that fluorescence became a negative. This actually became more universal with the start of the Rap report as he publishes a guide for the effect of fluorescence in his price list, although I am not sure when exactly he started to do that. The late seventies were a tumultuous time in our industry as the price for a one carat diamond that was graded by GIA to be D-IF went from (pricing approximate, I am old and my memory may not be exact) $2,500 per carat wholesale in 1972 to $65,000 per carat between dealers in the NY Diamond Buyer''s Club in Feb of 1980 only to fall back to about $15,000 per carat by June of 1980.


Tumultuous, but VERY VERY interesting!


Wink


P.S. The story of the Rapaport list and the death threats to Martin are another interesting part of this time period, and I imagine already covered somewhere in this wonderful forum.


That is such an interesting story! Thank you for sharing it and educating me. I will look into the Rapaport story. Fascinating.

Post by Isabelle » June 22nd, 2010, 3:50 am
Date: 6/22/2010 8:51:04 AM
Author: Wink
Date: 6/21/2010 6:34:31 PM

Author: Isabelle

John, as always your knowledge is overwhelming. So interesting to note that they''re hard to even find these days and that the discount isn''t usually that much. But then why did that other PSer say she was able to get a much larger stone by going with strong fluor? In any case, when I''m back on my computer I''ll read the article you linked to. I''m currently posting from iPhone which is hard. :-) Thank you John!


Just to point out that John was referring to overblues, the stones that look oily out of doors. These unpleasant looking stones trade at large disounts, unlike the small discounts of fluorescent stones that may or may not have a slight powder blue glow out of doors.


As has been stated above, stones that fluoresce with a beautiful glow used to sell for quite a premium, 5 - 15% was common with an occassional stone bringing 20% if it was particularly striking out of doors. I used to sell many of them during my early days in the industry.


Along came the investment craze of the late 70''s and the shoe clerks now selling diamonds in telephone sweat shops could not understand nor explain fluorescence, and heavens forbid they should ever actually take one outside to see it. It was easier to just discount fluorescent stones than to train the (insult to telemarketers deleted).


Add in the fact that chain stores like Zales needed to buy thousands of diamonds at a time and they did not want to have to go through parcels to pick out the possible overblues, so they also refused to take parcels that contained anything with more than weak fluorescence and you have the beautiful fluorescent stones taking a hit and getting a bad name.


I once went with John Pollard to do a diamond sales training at a wonderful store. During the training session I asked how many disliked fluoresccent stones. Many hands went up. I asked why and many of the same things said above, ie, unpleasant look out of doors, etc, were mentioned. When I asked how many had actually taken one of the stones outside to look at them, not one hand went up! During the course of the day I took the time to take one of their store''s VSB diamonds outside with each of the people who raised their hand about not liking them.


All were surprised by the look of the stone out of doors. It simply was NOT what they had been led to expect. I made no attempt to convince them to like the fluorescent stone, although I think I the stone itself might have convinced some of them, but at least now they had actually seen the fallacy of what they had been saying sight unseen.


RE: why did that other PSer say she was able to get a much larger stone by going with strong fluor?


Without seeing the diamond it would not be possible to know, but given the large difference in price versus the known 1 - 5% discount offered at the trade level, I am going to surmise that it might have had to due with some other factor, ie second hand stone, cutting quality, had the stone in house for years and needed to move it, etc. etc. I can only guess of course, since I know nothing of the stone, but I will guess that there were factors other than fluorescence involved


RE: Rock Diamond''s comment: ... statement about negative comments about fluorescence- no question such misinformation is out there. (bolding is mine)


Sadly, I complete concordance with this. It is amazing to me how much false information about such issues is touted as gospel in the jewelry trade. I can hear the planning session at Jewelers Misinformation Training now. ''Hey, 99.5% of strongly blue fluorescent stones are beautiful and the rest vary in how ugly they are, we better warn the public away from all such stones and sell them all at a huge discount, especially the beautiful ones, just to be safe. Oh, and be sure not to tell them about the beautiful ones, we don''t want to confuse the issue!''


Sigh.


Wink







This history is very interesting. And your point on not having all the stats on the diamond in question is excellent. Thanks Wink.

Post by uvaray » June 22nd, 2010, 3:58 am
Wow - This is quite a discussion. I read all your responses carefully and I feel like we shared a moment - we laughed, we cried, we tried to fix the internet. Even the comic pictures were great!

Basically, these are my takeaways...please tell me if I''m wrong:
1 - I should not consider "value" because I''m screwed in the secondary market anyway so I should get what I want.
2 - There''s still significant misconception about fluorescence. Just about everywhere I looked, I''ve read that the milky or hazy is a rare and I should not be worried. I''ve seen videos and pictures of this as well...but uneducated people put a negative connotation to fluorescence.
3 - Thanks to all your history, I now know that one of the main reasons for the "devalue" of diamonds with fluorescence is from sales people not being able to explain fluorescence. To me this is very simple, but most people can''t (or won''t) listen to anything semi-complicated. UV rays are light rays w/ short wavelengths that human''s can''t see. Because these rays have short wavelengths, they produce blue/purpleish color. Therefore, it''s natural for the diamond to emit the bluish color, if it can reflect the uv rays. And what the fluorescence diamond is doing is segmenting the light spectrum during the "light bounce back" even more than the non-fluorescence diamonds. If I were a physicist, I''d actually prefer a diamond w/ fluorescence because I can perform more tests w/ varying light spectrums.
4 - A few of you made some really good points for my specific case on how it would look in a club, hanging out w/ drunk people. It serves multiple purposes, including serving as a glow stick.

I actually like the bluish glow and I''d like to get this. However, take-away #2 might be the decisive point. Because there are so many misconceptions about fluorescence, my girl friend might be mortified to find her diamond glow. Especially since diamonds are regarded as "colorless" stones. And uneducated people might then question the legitimacy of her stone and I basically would have to explain to these uneducated, non-PriceScope reading savages. This just seems like too much work.

Post by Stone-cold11 » June 22nd, 2010, 4:17 am
Date: 6/22/2010 9:58:45 AM
Author: uvaray

3 - Thanks to all your history, I now know that one of the main reasons for the 'devalue' of diamonds with fluorescence is from sales people not being able to explain fluorescence. To me this is very simple, but most people can't (or won't) listen to anything semi-complicated. UV rays are light rays w/ short wavelengths that human's can't see. Because these rays have short wavelengths, they produce blue/purpleish color. Therefore, it's natural for the diamond to emit the bluish color, if it can reflect the uv rays. And what the fluorescence diamond is doing is segmenting the light spectrum during the 'light bounce back' even more than the non-fluorescence diamonds. If I were a physicist, I'd actually prefer a diamond w/ fluorescence because I can perform more tests w/ varying light spectrums.

Wrong. Not how fluorescence work. An invisible ray reflected back is still invisible. It is quantum mechanics. In the atom that absorbed the UV (any rays actually) rays, the electron is excited, jumps to a higher energy state, when it relaxes, it gives off a particular wavelength of light (color), this color light is specific to that atom/molecule, and that is fluorescence, it is a light emitted, not reflected.

Post by uvaray » June 22nd, 2010, 4:38 am
Ok. That make sense. Laws of thermodynamics transfers energy from an "excited" form to "relax" form through light. But since the atoms still absorb UV light, which is blue/purplish in color, this does explain the color itself. Materials emit "color" based on the light rays they absorb.

Post by Stone-cold11 » June 22nd, 2010, 4:48 am
Date: 6/22/2010 10:38:53 AM
Author: uvaray
Ok. That make sense. Laws of thermodynamics transfers energy from an ''excited'' form to ''relax'' form through light. But since the atoms still absorb UV light, which is blue/purplish in color, this does explain the color itself. Materials emit ''color'' based on the light rays they absorb.


Not true. How do you explain other color fluorescence with that explanation? Yellow fluor with Ultra Yellow rays? Materials emit colors based on how fast and how much they relax from their excited state.

Post by uvaray » June 22nd, 2010, 5:03 am
Ok. I thought about my statement and that doesn't make sense. But, then yours doesn't either. Colors are based on light rays the material absorbs. But, if the material absorbs "invisible" colors, then we still shouldn't be able to see these colors. Unless the only thing we're seeing is not the colors but only the energized glow.

Not that the whys really add anything of value to the fluorescence discussion......

Post by Wink » June 22nd, 2010, 5:09 am
Date: 6/22/2010 9:58:45 AM
Author: uvaray
Wow - This is quite a discussion. I read all your responses carefully and I feel like we shared a moment - we laughed, we cried, we tried to fix the internet. Even the comic pictures were great!

Basically, these are my takeaways...please tell me if I''m wrong:
1 - I should not consider ''value'' because I''m screwed in the secondary market anyway so I should get what I want.
2 - There''s still significant misconception about fluorescence. Just about everywhere I looked, I''ve read that the milky or hazy is a rare and I should not be worried. I''ve seen videos and pictures of this as well...but uneducated people put a negative connotation to fluorescence.
3 - Thanks to all your history, I now know that one of the main reasons for the ''devalue'' of diamonds with fluorescence is from sales people not being able to explain fluorescence. To me this is very simple, but most people can''t (or won''t) listen to anything semi-complicated. UV rays are light rays w/ short wavelengths that human''s can''t see. Because these rays have short wavelengths, they produce blue/purpleish color. Therefore, it''s natural for the diamond to emit the bluish color, if it can reflect the uv rays. And what the fluorescence diamond is doing is segmenting the light spectrum during the ''light bounce back'' even more than the non-fluorescence diamonds. If I were a physicist, I''d actually prefer a diamond w/ fluorescence because I can perform more tests w/ varying light spectrums.
4 - A few of you made some really good points for my specific case on how it would look in a club, hanging out w/ drunk people. It serves multiple purposes, including serving as a glow stick.

I actually like the bluish glow and I''d like to get this. However, take-away #2 might be the decisive point. Because there are so many misconceptions about fluorescence, my girl friend might be mortified to find her diamond glow. Especially since diamonds are regarded as ''colorless'' stones. And uneducated people might then question the legitimacy of her stone and I basically would have to explain to these uneducated, non-PriceScope reading savages. This just seems like too much work.


Hmm, as per your comment on take-away #2, that might be something you discuss with your fine lady.  She might be one of those people who would relish it, or she might be one who would hate it.  As for having to explain to the savages, well that would excite me no end as I love a good cause to champion.

Stone has addressed the issue of the higher state, but I have not seen much mention of the fact that fluorescence can be many colors, incuding yellow and red and can be VERY unattractive at times.  This is yet another reason why a stone really needs to be seen to be fully appreciated, whether in the bad sense or in the good sense of appreciation.

Wink

Post by Stone-cold11 » June 22nd, 2010, 5:15 am
Quantum physic. Excited material emit lights energy to loose the extra energy to return to the more stable base state, before excitation, it is not a reflection of light. Why is glow not a light?

Post by uvaray » June 22nd, 2010, 5:23 am
Glow can emit light, but it''s not the glow itself that''s producing light. Glow is a heated state and it''s the heat that''s dissipating the light.

Regardless, what you''re saying makes sense logically.

Post by Stone-cold11 » June 22nd, 2010, 5:35 am
Date: 6/22/2010 11:23:34 AM
Author: uvaray
Glow can emit light, but it''s not the glow itself that''s producing light. Glow is a heated state and it''s the heat that''s dissipating the light.

Regardless, what you''re saying makes sense logically.


Heat is another form of an excited state, it is at a higher energy then the surrounding.

Post by uvaray » June 22nd, 2010, 5:37 am
I basically said I agree with you......you provided information that I didn't consider and I thought it was a very good point.

Post by Isabelle » June 22nd, 2010, 5:52 am
Date: 6/22/2010 9:58:45 AM
Author: uvaray



I actually like the bluish glow and I''d like to get this. However, take-away #2 might be the decisive point. Because there are so many misconceptions about fluorescence, my girl friend might be mortified to find her diamond glow. Especially since diamonds are regarded as ''colorless'' stones. And uneducated people might then question the legitimacy of her stone and I basically would have to explain to these uneducated, non-PriceScope reading savages. This just seems like too much work.


I think you are making the right decision b/c strong or very strong fluor is discounted in the trade. You might only get a 1% discount when you buy the stone, but you will take more than a 1% hit on the fluor should you try to sell it later. Also, it is controversial. If it weren''t, upper end jewelers wouldn''t make a policy against carrying them particularly for colorless diamonds. And third, there are people who would see it and think "Oooh. It is glowing. That''s fluorescence. That''s baaad." And even if they are dead wrong, that''s what they''d think. In a lot of ways, people have been conditioned to view the presence very strong fluor in a diamond report as poorly as they view the presence of carbon when they examine a diamond with their own eyes. It might be wrong, but it''s definitely the standard belief. And I think AGS grades down a diamond with strong or very strong fluor, so again, the trade is discounting it for a reason. When you can get a beautiful, white, well cut diamond without the presence of strong fluor, why not go that route?

Post by Stone-cold11 » June 22nd, 2010, 6:49 am
Date: 6/22/2010 11:52:03 AM
Author: Isabelle
And I think AGS grades down a diamond with strong or very strong fluor, so again, the trade is discounting it for a reason.


And where did you get that piece of information from? Never heard of that before and my VSB is from AGS and cut graded AGS0.

Post by Dreamer_D » June 22nd, 2010, 7:00 am
Date: 6/22/2010 8:01:53 AM
Author: Isabelle

Date: 6/22/2010 1:08:53 AM
Author: dreamer_d
I do not consider Tiffany''s to be a source of pure unbiased information about diamonds.


I also do not consider McDonald''s to be to be a source of pure unbiased information about nutrition.




That''s sort of sophistry though, isn''t it Dreamer? McDonalds isn''t known as the world''s finest purveyor of burgers. A better analogy would be for you to say that you don''t consider Ferrari to be a source of pure unbiased information about how to make a fast sports car. They might not be unbiased about their own cars, but I think most people would defer to their expertise on on how to make one run fast.
Image

I think McDonald''s has perfected the art of marketing its goods to its target population and highlighting or spinning information in a way that meets its needs, and therin lies my comparison with a multinational corporation like Tiffany. You may not see the parallel, but I certainly do. And I would also take with a grain of salt the information that Ferrari provided in marketing information for its consumers, especially when some of that information was contradicted by many other experts.

One Ring to rule them all.


Post by Dreamer_D » June 22nd, 2010, 7:05 am
Date: 6/22/2010 8:05:31 AM
Author: Isabelle

Date: 6/22/2010 1:25:38 AM
Author: yssie
Some interesting reading I meant to attach earlier, incl an older article so it would probably be wise to proof along the wayImage


http://lgdl.gia.edu/pdfs/W97_fluoresce.pdf


http://www.goodoldgold.com/4Cs/Color/Fluorescence/

http://en.wikipedia.org/wiki/Crystallographic_defects_in_diamond


Thanks Yssie! I read the GIA article! They didn''t get to study VSB fluor diamonds though, b/c to John''s point, they couldn''t find any. I hope they do more studies on it. A follow up would be great. Thank you again for posting the links.

Just for clarification, they actually found VSB stones, they could not find any "overblues" that showed oily or milky appearances: "Although yellow fluorescent diamonds and “overblues” are also of concern in the trade, such stones are so rare that we could not assemble appropriate examples to perform a comparable study."

GIA''s conclusions: "Unlike the notion held by many in the trade, fluorescent diamonds are not as prevalent as nonfluorescent stones, as the GIA Gem Trade Laboratory sample data for more than 26,000 diamonds showed. 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"

The highlighted is of course what we always recommend on PS.

One Ring to rule them all.


Post by Dreamer_D » June 22nd, 2010, 7:28 am
Date: 6/22/2010 11:52:03 AM
Author: Isabelle

Date: 6/22/2010 9:58:45 AM
Author: uvaray



I actually like the bluish glow and I''d like to get this. However, take-away #2 might be the decisive point. Because there are so many misconceptions about fluorescence, my girl friend might be mortified to find her diamond glow. Especially since diamonds are regarded as ''colorless'' stones. And uneducated people might then question the legitimacy of her stone and I basically would have to explain to these uneducated, non-PriceScope reading savages. This just seems like too much work.


I think you are making the right decision b/c strong or very strong fluor is discounted in the trade. You might only get a 1% discount when you buy the stone, but you will take more than a 1% hit on the fluor should you try to sell it later. Also, it is controversial. If it weren''t, upper end jewelers wouldn''t make a policy against carrying them particularly for colorless diamonds. And third, there are people who would see it and think ''Oooh. It is glowing. That''s fluorescence. That''s baaad.'' And even if they are dead wrong, that''s what they''d think. In a lot of ways, people have been conditioned to view the presence very strong fluor in a diamond report as poorly as they view the presence of carbon when they examine a diamond with their own eyes. It might be wrong, but it''s definitely the standard belief. And I think AGS grades down a diamond with strong or very strong fluor, so again, the trade is discounting it for a reason. When you can get a beautiful, white, well cut diamond without the presence of strong fluor, why not go that route?

Really? Where is this shown?  This implies a double hit for flour on the market, once at primary and once at secondary sale. Seems more rasonable to assume that if you get 35% of primary when you sell at secondary, that proportion will holf no matter the characteristics of the stone. So you may get 1% less on resale, but you also paid 1% less, and therefore it is all a wash.  

And I do NOT think it is good practice to look at upper end jewlers and say, "Well they do it, then it must be right/meaningful" when a major reason it is controversial in the first place is because large diamond vendors decided it was controvercial. It is tautology.

I have no vested interest in Flour or no Flour, but I really think there are certain issues that have been marketed to create a tempest in a tea pot, and the dangers of flour is one of them. The "tint" or "yellow" in I/J colored stones is the other. Neither of these misapprehensions benefit consumers and that is why I keep addressing this issue over and over in this thread.

One Ring to rule them all.


Post by Rockdiamond » June 22nd, 2010, 7:44 am
My experience is that in higher colors and clarity, the discount on a strong Blue diamond is much greater than 1%- on large stones I''ve seen it as high as 15% as compared to an inert stone
David Friedlander
President- Diamonds by Lauren/Rock Diamond Corp- Located on 47th Street in NYC
http://diamondsbylauren.com

Post by John Pollard » June 22nd, 2010, 7:49 am
Date: 6/21/2010 6:34:31 PM
Author: Isabelle

John, as always your knowledge is overwhelming. So interesting to note that they're hard to even find these days and that the discount isn't usually that much. But then why did that other PSer say she was able to get a much larger stone by going with strong fluor? In any case, when I'm back on my computer I'll read the article you linked to. I'm currently posting from iPhone which is hard. :-) Thank you John!

You're welcome for the info. I wanted to mention that I also enjoyed reading Wink's historical perspective.

...And I think AGS grades down a diamond with strong or very strong fluor...

AGS doesn't downgrade for fluorescence. No lab does, that I know of.

It may be helpful to offer this perspective: Fluorescence discounting becomes somewhat negligible when you compare it to discounting in categories considered more significant, like color or clarity. Move from D to E in color, or IF to VVS in clarity and you'll find a meaningful discount. Now try moving 5 grades. And, like fluorescence, the discounts may or may not reflect something that's visible to the casual viewer.

On the overall topic GIA's study concludes well, and offers a gentle spanking to trade members who would carrry on old wives' tales about the "evils" of fluorescence: 

"Unlike the notion held by many in the trade, fluorescent diamonds are not as prevalent as nonfluorescent stones, as the GIA Gem Trade Laboratory sample data for more than 26,000 diamonds showed. 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."

Having given this perspective, it's also important to say that it is anyone's right to HATE fluorescence. No problem. I defend their right to hate it. To spit when they hear it. To curl their fists aloft and with angry howls break the clouds!  

In such matters involving personal preference we should just remember that - as we exercise our own right to choose - it's a good idea to respect that others may choose differently... whether fluoro, color, clarity, cut or pie flavor. It's a two-way street.

John Pollard, BME BA AS (WSU) AJP (GIA)
US Executive, Crafted By Infinity
www.CraftedByInfinity.com

Post by Rockdiamond » June 22nd, 2010, 8:38 am
Date: 6/22/2010 1:49:03 PM
Author: John Pollard
Date: 6/21/2010 6:34:31 PM

Author: Isabelle


John, as always your knowledge is overwhelming. So interesting to note that they''re hard to even find these days and that the discount isn''t usually that much. But then why did that other PSer say she was able to get a much larger stone by going with strong fluor? In any case, when I''m back on my computer I''ll read the article you linked to. I''m currently posting from iPhone which is hard. :-) Thank you John!


You''re welcome for the info. I wanted to mention that I also enjoyed reading Wink''s historical perspective.


...And I think AGS grades down a diamond with strong or very strong fluor...


AGS doesn''t downgrade for fluorescence. No lab does, that I know of.


It may be helpful to offer this perspective: Fluorescence discounting becomes somewhat negligible when you compare it to discounting in categories considered more significant, like color or clarity. Move from D to E in color, or IF to VVS in clarity and you''ll find a meaningful discount. Now try moving 5 grades. And, like fluorescence, the discounts may or may not reflect something that''s visible to the casual viewer.


On the overall topic GIA''s study concludes well, and offers a gentle spanking to trade members who would carrry on old wives'' tales about the ''evils'' of fluorescence:


''Unlike the notion held by many in the trade, fluorescent diamonds are not as prevalent as nonfluorescent stones, as the GIA Gem Trade Laboratory sample data for more than 26,000 diamonds showed. 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.''


Having given this perspective, it''s also important to say that it is anyone''s right to HATE fluorescence. No problem. I defend their right to hate it. To spit when they hear it. To curl their fists aloft and with angry howls break the clouds!


In such matters involving personal preference we should just remember that - as we exercise our own right to choose - it''s a good idea to respect that others may choose differently... whether fluoro, color, clarity, cut or pie flavor. It''s a two-way street.


I agree with a lot of what you wrote John- I''m a big advocate for the "live and don''t insult other''s taste about diamonds " part.
We might have a different perspective on the pricing issue- because we''re buying polished from a many sources- meaning that strong blue stones, which are already on the market are what I based my statement on.
Since you are representing a cutter, the discounts you offer for a strong blue might be much smaller ( justifiably so) as compared to stones on the general market.

I do disagree, slightly, about the part in bold- in one specific area. That being Fancy Light, Fancy Yellow, and Fancy Intense Yellow stones with strong blue.
It would be possible to make a case that GIA is tougher on these colors when they are strong blue- although part of this has to do with the stronger effect on perceived color these stones experience. The result is that a Fancy Yellow with Strong blue, viewed in "normal" lighting, may have a color as strong as an inert Fancy Intense Yellow.
David Friedlander
President- Diamonds by Lauren/Rock Diamond Corp- Located on 47th Street in NYC
http://diamondsbylauren.com

Post by Wink » June 22nd, 2010, 9:30 am
Date: 6/22/2010 1:49:03 PM
Author: John Pollard

You''re welcome for the info. I wanted to mention that I also enjoyed reading Wink''s historical perspective.


Thanks John,

Kind of daunting in a way, living through a period that so many of you think of as historical.  LOL!  Some day time will catch up with you and you will be told by your children that your historical perspective is interesting.  Hopefully I will still be here, selling diamonds from my wheel chair and laughing at the irony...

Wink, Geezer Extraordinaire

Post by John Pollard » June 22nd, 2010, 9:38 am
Date: 6/22/2010 2:38:03 PM
Author: Rockdiamond

I do disagree, slightly, about the part in bold- in one specific area. That being Fancy Light, Fancy Yellow, and Fancy Intense Yellow stones with strong blue.
It would be possible to make a case that GIA is tougher on these colors when they are strong blue- although part of this has to do with the stronger effect on perceived color these stones experience. The result is that a Fancy Yellow with Strong blue, viewed in 'normal' lighting, may have a color as strong as an inert Fancy Intense Yellow.

I think you interpreted my statement outside of the envelope I intended. I simply noted that there isn't a policy to penalize (downgrade) fluorescence by lowering another grade. There are other attributes, like details of girdle, culet and finish, which may result in a penalty (a downgrade) to another grade.

Of course there is influence as you note in the fancy colors, especially since they are judged face-up. In the trade a lot of people feel there is also potential for positive influence in near-colorless and down, even when graded face-down. In that broad context I guess judgments can go down or up, depending on the case.

John Pollard, BME BA AS (WSU) AJP (GIA)
US Executive, Crafted By Infinity
www.CraftedByInfinity.com

Post by Allison D. » June 22nd, 2010, 9:53 am
Date: 6/22/2010 1:00:26 PM
Author: dreamer_d

Date: 6/22/2010 8:01:53 AM
Author: Isabelle


Date: 6/22/2010 1:08:53 AM
Author: dreamer_d
I do not consider Tiffany''s to be a source of pure unbiased information about diamonds.


I also do not consider McDonald''s to be to be a source of pure unbiased information about nutrition.




That''s sort of sophistry though, isn''t it Dreamer? McDonalds isn''t known as the world''s finest purveyor of burgers. A better analogy would be for you to say that you don''t consider Ferrari to be a source of pure unbiased information about how to make a fast sports car. They might not be unbiased about their own cars, but I think most people would defer to their expertise on on how to make one run fast.
Image

I think McDonald''s has perfected the art of marketing its goods to its target population and highlighting or spinning information in a way that meets its needs, and therin lies my comparison with a multinational corporation like Tiffany. You may not see the parallel, but I certainly do. And I would also take with a grain of salt the information that Ferrari provided in marketing information for its consumers, especially when some of that information was contradicted by many other experts.

Hee hee - lest anyone think I was talking about the ''mcdonald''s equivalent'' of a PS expert earlier....in my case, it wasn''t Tiffany.

The topic of the GIA study came up in conversation with a well-respected PS vendor, and he was fairly emphatic in his disagreement with the results.  He felt that it (VSB) has to affect light performance in stones at least 2/3 of the time.

Since that''s not my area of training, I didn''t debate and we moved on. 

Like any other highly technical field, experts can and do disagree from time to time, and in those cases the answer is somewhere short of absolute.
(formerly known as aljdewey)

Post by Stone-cold11 » June 22nd, 2010, 9:56 am
Date: 6/22/2010 3:53:03 PM
Author: Allison D.

Hee hee - lest anyone think I was talking about the ''mcdonald''s equivalent'' of a PS expert earlier....in my case, it wasn''t Tiffany.

The topic of the GIA study came up in conversation with a well-respected PS vendor, and he was fairly emphatic in his disagreement with the results. He felt that it (VSB) has to affect light performance in stones at least 2/3 of the time.

Since that''s not my area of training, I didn''t debate and we moved on.

Like any other highly technical field, experts can and do disagree from time to time, and in those cases the answer is somewhere short of absolute.


I think I know who since WF''s ACA will not include fluor stones.

Post by missydebby » June 22nd, 2010, 9:59 am
After reading this thread, I am soooo wanting to check out these here glowin'' stones.

As far as owning one, I''d love to as part of a collection of pieces, but for my ering - I knew I wanted a white clear poppin'' little number. For me, "mind clean" for my ering is ice cold and clear.

I can imagine owning one as a pendant. And I''d try to get as strong a FL as possible without milkiness. Because for me it would have value both as a beautiful object and as a conversation piece. The only problem with having one as an ering (that you wear all the time) would be having the subject come up if you don''t feel like educating people. That can be a drag.

Post by Isabelle » June 22nd, 2010, 10:00 am
Date: 6/22/2010 12:49:09 PM
Author: Stone-cold11
Date: 6/22/2010 11:52:03 AM

Author: Isabelle

And I think AGS grades down a diamond with strong or very strong fluor, so again, the trade is discounting it for a reason.



And where did you get that piece of information from? Never heard of that before and my VSB is from AGS and cut graded AGS0.



I was mistaken on that.- I apologize. I thought I had seen an AGS Report wherein the grade was given next to the fluorescence statement, (like they do with color and such) but I was wrong in my recollection. I don''t really know what you are arguing about anymore though. I have been fully convinced by you, John and David that some Strong or Very Strong fluor stones can look amazing. But I hope you aren''t trying to say that the market grades them equally to non-strong fluor stones. That''s simply not true.

Post by Isabelle » June 22nd, 2010, 10:02 am
Date: 6/22/2010 1:00:26 PM
Author: dreamer_d

I think McDonald''s has perfected the art of marketing its goods to its target population and highlighting or spinning information in a way that meets its needs, and therin lies my comparison with a multinational corporation like Tiffany. You may not see the parallel, but I certainly do.


You''re right. I don''t see the parallel. But I doubt we will see eye to eye on this one so it''s probably best to let it go.
Image

Post by Rockdiamond » June 22nd, 2010, 10:06 am
Date: 6/22/2010 3:38:54 PM
Author: John Pollard
Date: 6/22/2010 2:38:03 PM

Author: Rockdiamond


I do disagree, slightly, about the part in bold- in one specific area. That being Fancy Light, Fancy Yellow, and Fancy Intense Yellow stones with strong blue.

It would be possible to make a case that GIA is tougher on these colors when they are strong blue- although part of this has to do with the stronger effect on perceived color these stones experience. The result is that a Fancy Yellow with Strong blue, viewed in ''normal'' lighting, may have a color as strong as an inert Fancy Intense Yellow.



I think you interpreted my statement outside of the envelope I intended. I simply noted that there isn''t a policy to penalize (downgrade) fluorescence by lowering another grade. There are other attributes, like details of girdle, culet and finish, which may result in a penalty (a downgrade) to another grade.


Of course there is influence as you note in the fancy colors, especially since they are judged face-up. In the trade a lot of people feel there is also potential for positive influence in near-colorless and down, even when graded face-down. In that broad context I guess judgments can go down or up, depending on the case.


Interesting distinction John!
My interpretation is that the downgrades for things like girdle, culet and finish are an integral part of the cut grade itself. The way I see it, it''s really a question of the methodology used to grade the fancy colors that allows this "unwritten rule"- which is not a rule at all- but rather the result of how the colors are graded.


Wink, I''m 53- who you calling old???
David Friedlander
President- Diamonds by Lauren/Rock Diamond Corp- Located on 47th Street in NYC
http://diamondsbylauren.com

Post by Stone-cold11 » June 22nd, 2010, 10:12 am
Date: 6/22/2010 4:00:29 PM
Author: Isabelle

But I hope you aren''t trying to say that the market grades them equally to non-strong fluor stones. That''s simply not true.



Define market grade? Who set them and by what standard? Enforceable? Why?

Post by Yssie » June 22nd, 2010, 10:14 am
Date: 6/22/2010 7:59:32 AM
Author: Isabelle

Actually,that's not arbitrary either. They don't sell stones with inclusions that are visible to the naked eye or a standard loupe. I have an SI1 and I can see the inclusion.

Just a note - this doesn't mean that all SI2s have inclusions visible to the naked eye. All SI1s have inclusions visible in the standard loupe, that's how they're graded, and some SI1s have inclusions visible to the naked eye - as do some VS2s, esp. in larger sizes
Some circumstantial evidence is very strong, as when you find a trout in the milk.
~H.D.Thoreau


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