Date: 6/22/2010 9:07:39 AM
Author: Stone-cold11
I meant over blue and I stand corrected. I hope that for your sake you can get more studies to back up your opinions. It would be great if the trade came to a consensus since one does not yet exist. Like all industries though, things are always evolving as industry learns more and technology improves.
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.
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.
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.
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
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.
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.Date: 6/22/2010 8:01:53 AM
Author: Isabelle
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.
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."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 way
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.
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.
You're welcome for the info. I wanted to mention that I also enjoyed reading Wink's historical perspective.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.
AGS doesn't downgrade for fluorescence. No lab does, that I know of.
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.
You''re welcome for the info. I wanted to mention that I also enjoyed reading Wink''s historical perspective.
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.
Thanks John,
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.
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.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. 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.Date: 6/22/2010 8:01:53 AM
Author: Isabelle
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.
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