Vol 3.6 "Artificial Lighting" June 14, 2004

It’s June 14, 2004, 11:35 AM. Last week we buried our 40th President of
the United States, Ronald Wilson Reagan. What an incredible life this man had
‘”successful actor, governor and then president. He met the love of his life
at age 41; the same age I am now. Wow. One of the things that most impressed
me about President Reagan (there are many), was his capacity to strive for
excellence. He didn’t seem like a man who settled'”even when he could have
retired many times over in the course of his life. It’s almost like he got
three lives out of his one life on earth. Each day when I wake up I promise
myself that I’m going to do my best, not waste time, and make a difference in
at least one other person’s life. It’s not always easy. I think there is a
lazy Fred inside of me that wants to perpetually goof off and stay in bed. I
fight with Lazy Fred every day. In fact, I fight with Lazy Fred, Angry Fred,
Sleepy Fred, and many other good-for-nothing Freds as well. It’s hard to know
when you’ve done your best. Leonardo DaVinci once said, ‘As a well spent day
brings happy sleep, so life well used brings happy death.’ President Reagan
had a life well used. I hope I can say the same some day.

Here is a sneak peek at the Article of the Month for July. All the Best.

Talk to you soon,


First Impressions on GIA’s New Cut Grading System

In 1955, Gemological Institute of America’s (GIA) Gem Trade Lab (GTL) began
issuing Lab Grading Reports for diamonds. Concept: In order to assign a
value to a diamond, you need to know its quality. GIA hit a home-run by
creating a standardized system for grading diamonds (the four C’s; carat
weight, clarity, color, and cut). Also, with GIA as an industry watch dog,
misgrading or misrepresentation by unscrupulous jewelers could be avoided.

At first, it worked. Jewelers knew that if they had a good diamond, the ideal
thing was to send it in for a Lab Grading Report. Then a funny thing
happened; others realized there was money to be made in having the power to
bless or condemn a diamond’s quality, so they started their own labs (EGL,
IGI, HRD, AGS, etc.).

The word certificate (see my article, Certifiable: Lab Grading Reports, Are
They Just a Piece of Paper?) started being thrown around and it was implied
that a diamond didn’t have any value without its ‘papers.’ What the public
wasn’t aware of, was the labs do not discriminate which diamonds they issue
reports on. Any diamond sent in, regardless of quality, got ‘papers’ (Lab
Grading Report) so the jeweler could reference it during the sale.

While I wrote at great length on the current validity of lab grading reports
in Certifiable: Lab Grading Reports, Are They Just a Piece of Paper, this
article focuses on a new aspect of Lab Grading Reports that will be
incorporated into the reports in the Fall of 2004 by GIA'”a cut grading
system. While the exact details are still unknown; here’s what we know for

According to Tom Moses, GTL’s VP, computer-generated models were used to
determine the most appropriate set of proportions (for round stones) to
increase the amount of sparkle (brilliance + dispersion) and scintillation of
a diamond to the viewer’s eyes. After the computer model calculations were
done, Human Eye Measurement (HEM) was needed to solidify the predictions. It
has been reported by GTL that over 65,000 observations were made to quantify
if human preferences matched what the computer light tracing experiments
predicted would be the most optimal way to cut a diamond. NOTE: While 65,000
observations sounds like 65,000 people were used in the trial, in fact only
350 people were used. Every time they looked at a diamond, even if it was
more than once, it was counted as an observation. (One million hits on a
website doesn’t mean one million unique visitors found the site.) A reported
2000 diamonds were used for the calculations.

Regardless, after GTL’s models suggested that the current cutting standards
for ‘Ideal’ or ‘Class 1’ were too strict, the 350 participants couldn’t agree
with GTL’s conclusions on which diamonds were more sparkly. Instead of going
back to the drawing board, GTL blamed the disagreement on poor lighting. They
then cranked up the lighting until the observations matched the predictions.

This leads me to an important point; the models appear to ignore
mathematicians Tolkowsky and Ditchburn’s work on proportions and light return
in respect to their guidelines for maximum and minimum tolerances. If larger
table percentages and larger depth percentages are acceptable, it will allow
jewelers to sell what was previously considered a poorly-proportioned diamond
as a well-proportioned one, as was first reported in the May 16, 2004 article
in National Jeweler by Victoria Gomelsky:

‘When the system is introduced, it will profoundly change the way that
manufacturers cut diamonds and retailers sell them. The latter are among
those who are concerned about the trade’s lack of preparedness for such a
development. They fear that consumers accustomed to the Ideal Cut will lose
confidence in the industry’s ability to agree on the issue of diamonds
appearance. But supporters say a third-party evaluation of cut will help
people at all points of the supply chain sell diamonds previously considered

In the article ‘Grading the Make’ by Rob Bates, Senior Editor of Jewelers
Circular Keystone, he writes that the only way GIA could get their numbers to
jive was to choose a ‘standardized lighting environment!’

Unless you’re Michael Jackson, you don’t live in a standardized lighting
environment! We live in cloudy days and fluorescent lit offices; sunny days
and candle lit restaurants. Any test to determine a diamond’s beauty must
consist of multiple lighting environments. The diamond that averages the best
under lighting conditions that range from the best to the worst should be
declared the winner. That’s how a decathlete is declared the world’s greatest
athlete. Not because he’s best in all events, but because his accumulative
score in ten events ranks him the best.

Labeling a diamond as well-proportioned when it isn’t is a lose-lose situation.

The founder and president of Diamond Cutters International, is one of the worlds top diamond experts, as well as a three-time Guinness Book record holder in jewelry design.
Fred The Diamond Guy
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