What is Fluorescence in a Diamond?
When it comes to loose diamonds I do much of the training myself. I have the trainee read a particular GIA book and then we go over questions as well selling techniques—only because GIA doesn’t teach selling techniques and I don’t want my employees to get bogged down with the technical lingo but instead how to romance the selling of a diamond.
Eventually, when going over how specific characteristics of a diamond can affect price—fluorescence came up. Unfortunately, when I was at GIA fluorescence was not emphasized and is really not explained in my books. Everything I know about fluorescence has come from wholesalers and learning as I go—how do I explain fluorescence to a staff in training? The only way I could explain it was to show a few diamonds I had on hand with fluorescence. Two of the fluorescing diamonds where in the Near Colorless range and made the diamonds appear whiter and sparkle more. Diamonds of the lower color—appeared to be milky looking and lacked luster.
Could any of you tell me how you would explain fluorescence to someone in training? Why diamonds fluorescence? What is fluorescence? Is it really a bad or good thing—this of course is somewhat opinion based?
FAVOUR commented:
I went to know what fluorescence and it'S USE
John Harris commented:
From the GIA website...
www.gia.edu/library/4286/6285/faq_detail_page.cfm What is
fluorescence? Is it something I should be concerned about? Answer:
Fluorescence is a phenomenon occurring in diamonds and other
gemstones. The fluorescence that occurs naturally in a diamond
arises from submicroscopic structures within the diamond when it is
exposed to UV light. Blue is the most common color of fluorescence,
but others colors are also possible. On our GIA Gem Laboratory
diamond grading reports, the strength of the fluorescence is noted
as none, faint, medium, strong, or very strong. Beginning with
medium, the color of the fluorescence will be noted (ex. blue,
yellow, green, etc.). If fluorescence is faint, the report will not
note the color. Blue is the most common color for a diamond to
fluoresce. GIA has extensively researched the subject of
fluorescence and we published a detailed article describing our
findings in the Winter 1997 issue of Gems & Gemology, entitled
"A Contribution to Understanding the Effect of Blue Fluorescence on
the Appearance of Diamonds." Some jewelers believe that
fluorescence is always an undesirable characteristic. However,
GIA's research indicates that fluorescence is not necessarily
negative, and in some cases, fluorescence actually has a positive
effect by making a diamond appear whiter. The publication is
here... lgdl.gia.edu/pdfs/W97_fluoresce.pdf
neil pennell commented:
Fluorescence can be an attribute or a hindrance depending on its
severity and how its presented. Extreme fluoresence can make a
stone look weird, I've heard it called greasy, but milky is
probably a better discription, In a high dollar stone even moderate
reaction is probably not good, as you may be competing against
another jeweler basically on the cert. Cert vs cert cutomers can
get pretty picayune, probably against their best interest(its
better to 'see' the stone, not get all hung up on minor specs). On
the other, hand moderate fluoescence can perk up a budget stone,
making it appear a little better than its color spec would suggest,
with the right customer this equates to more bang for the buck.
Alexanderr commented:
On floursence, remember that it accounts for only a small portion
of the variance. It is really unimportant as compared to other
factors, but it is a way of casting aspersions on someone else's
stones, if you are into that sort of thing. There was a nice piece
on flourescence in Gems and Gemology a couple of years ago. As I
recall, it came to the opposite conclusion: blue flourescence in
faintly yellow and lower stones would improve the color--that is
they would appear white when flourescing, but in white stones the
advantages of blue flourescene were not siginificance and the
milkyness was an issue.
