How Important Is Diamond Cut Grade?

A Quick Lesson "Beyond the 4 Cs" for DiamondTherein lies the dilemma, the trade off the cutting
Shoppersfactory has to make, size and number of stones
The 4 C's of diamond grading are not four C's atover cut quality. For obvious business reasons, the
all because the most important attribute isquality can often be compromised.
"beyond the 4 Cs", beyond what the eye canIt is the rarity of diamonds that drive their value,
see, it adds or detracts from a diamond's beautythe rarer the diamond, the higher the price. Rarity
and more importantly "value" more than anyis defined by the combination of all the 4Cs, this is
other variable in diamond grading.why an "Ideal Cut" diamond demands the
The B in "beyond" stands for brilliance, the mostpremium pricing found in the market place. The
important attribute of a gem grade diamond, inmost rough is lost when creating this rare and
that the beauty of a diamond is actually themagnificent diamond, thus this cut is reserved for
beauty of the brilliance of light. Inherently we allthe highest quality color and clarity stones, only
know this when we see a beautiful stone, but wegem grade stones will be ideal cut. So while there
don't know why. All diamonds appear beautiful andare quality tradeoffs in color and clarity, due to
brilliant in the light of the jewelry store "spotthe loss of rough, no other aspect affects value
lights", but it is in the natural light that the(and price) greater than cut.
difference can truly be seen between an excellentIdeal Cut Diamonds
cut diamond and a poorly cut diamond.The "Ideal Cut" diamond is elusive because it is so
I'm speaking specifically in regard to "gem gradetechnical in nature and cannot be seen by the
diamonds", diamonds with color at J or above andhuman eye. For example, the parameters below
clarity above SI-2. The brilliance (cut) is the mostdefine the Ideal Cut range,
important consideration in the evaluation of quality.Ideal Cut Parameters:
The cut can influence a diamonds value and price- Table Diameter: 52.4% to 57.5%
by as much as 25%. Until recently, it was the- Crown Angle: 33.7 degrees to 35.8 degrees
least documented or understood by the- Girdle Thickness: Thin to Slightly Thick (.51% to
consumer when purchasing a diamond.2.95%)
Cut, the proportions and finish, are what- Pavilion Angle: 40.2 degrees to 41.25 degrees
determine a diamonds optical qualities and cut- Culet: None (Pointed) to Medium
(brilliance) grading assesses the nature of those- Total Depth: 56.88% to 63.92%
optical qualities that make up diamonds brilliance -You can learn more about Ideal Cut Diamonds in
the amount of light and the nature of and balancethe Diamond Education Center.
of light returned to the viewers eye. The cut ofIn my experience, what's important for a
the diamond is also the "unnatural" feature of theconsumer to be aware of is hidden flaws in a
stone, crafted by a human cutter, the artist, anddiamonds cut. When comparing two stones and
the businessman.one seems like a "great deal", this is often where
The Rarity of Diamonds and Cut Dilemmathe discounting occurs (this and fluorescence,
About half of the world's diamonds are minedanother topic). Or, worse yet, proper discounting
from central and southern Africa and the otherhas not occurred. If a consumer is not aware and
half come from various countries such as Canada,merely compares color and clarity he/she may
India, Russia, Brazil, and Australia. Diamonds arenot get the full value unless they know to assess
usually mined from volcanic pipes deep in thethe cut. This does not imply that a diamond needs
earth, where the high pressure and heat provideto be an Ideal Cut to be beautiful; on the
the conditions necessary for diamond formation.contrary, many diamonds in lower cut grades are
Following the technical mining process, the roughbeautiful but you don't want to pay too much.
stones are shipped out to be cut and polished.Ask for Documentation
Traditional diamond cutting centers are located inThe key to diamond shopping, ask for
Antwerp, Amsterdam, Johannesburg, New York,documentation on the diamond cut grade. GIA
and Tel Aviv. Centers have also been recentlyrecently started including this on their
established in China, India, and Thailand.certifications, AGS also has a cut grade. But to
When the "rough" reaches its location, the difficultget the exact proportions, degrees, and angles a
task of cutting can begin. The cutting of diamondsmore detailed analysis is required. This is typically
requires not only a great deal of skill, but a greatdone on a Sarin Proportion Analyzer, which will
deal of specialized tools as well. Cutters must useprovide exact measurements of any diamond
special saws, blades, and grinders to cut a rougheven as small as .10ct.
diamond into a brilliant stone. And even withSo when asked, how important is cut grade, I
modern machinery and techniques the cuttingalways say it is the MOST important. It drives
process always results in a dramatic loss ofbrilliance, beauty, price and ultimately long term
weight in the rough. In fact, is it rarely less thanvalue. At my company, Diamond Design Co. we
50% of the total carat weight that is lost in thefocus on the cut of every stone, from the
cutting and faceting process.smallest to largest, each stone is hand selected,
The cutter has two objectives when cutting aand prior to mounting, measured on a Sarin
stone, although they often conflict with oneProportion Analyzer and selected for ideal
another. The cutter wants to keep the mostproportions and brilliance creating the most
weight possible out of the rough, but also createbeautiful pieces of diamond jewelry.
a cut which is highly valued by the market place.Learn before you buy, read "Beyond the 4Cs".