
Diamond Cut: The Shape
CUT of a diamond pertains both to the
shape (round, marquise, princess, etc.), and to the make (how well it is cut for proportion
and finish). These are the only factors in diamond grading that
are controlled by human hands.
First we will talk about
the eight major diamond shapes, your first decision when shopping
for a diamond. On the next page we will describe a few details
about the make of a diamond.
Diamond Shapes

The first step in
choosing a diamond
often involves selecting your favorite (or her favorite) shape.
The Round Brilliant is by far the most popular shape, and it
is the most readily available in every possible quality and size.
Contrary to popular
belief and perhaps your experience in most stores, fancy-shaped
diamonds (as all non-round diamonds are called) are often less
expensive than their round brethren... at the wholesale level.
The Princess cut is
becoming popular because it is both brilliant and unique. The
Princess shape actually saves money for a cutter, since it is
closest to the octahedral "habit" of rough diamond
crystal, the most common formation of diamond in the rough. (The
octahedron is like two pyramids base to base.)
Compared to a Round
Brilliant, a cutter can retain more of the original crystal when
cutting an octahedron into a Princess shape. The square corners
of the rough need to be cut away to create a Round, but they
are saved when cutting a Princess.
The more he saves of
his original rough crystal, the less the cutter loses on his
financial investment in the stone, and therefore you pay less
as well.
But many shapes can
be beautiful if they are cut well, including the Marquise, Oval,
Pear, Radiant, Heart, Emerald and other major shapes. But all
fancy shapes have an inherent difference in the physics of light.
The longer shapes have a slight "bow tie" effect. This
means they have a small zone in the center where light leaks
out the bottom, creating a darker area in the shape of a bow
tie. This is especially true for the Pear, Oval, Marquise, and
Heart shapes.
For ideal proportions
that maximize brilliance, fire and sparkle, you can't beat the
new Round Brilliant Ideal Cut. The science of cutting a diamond
to bring out the full potential of its beauty has developed significantly
in the past 10 years. Many diamond cutters now specialize in
creating ideal proportions, and such stones have become quite
popular. Ideal Cut diamonds command a slight premium because
of 1) the extra care and skill needed during cutting, 2) more
of the rough is usually cut away, and 3) they are scarce and
in high demand.
WARNING:
Knowing the 4 Cs is NOT enough to price a diamond accurately.
At least 13 factors
affect diamond value, including fluorescence, table percentage,
symmetry and other crucial details. However, the 4 Cs are a good
place to learn the basics.
To learn how to calculate a fair price for any
diamond, use our Diamond Pricing Tutorial. It guides you step-by-step through the process of using the best pricing tool online: the large diamond price databases, so you can research prices using real data for stones that are available in the market right now. Nothing is more accurate. The other key is using a helpful, honest, diamond expert who is looking at diamonds every day. If you cannot find a good jeweler, we rate the top dealers for you.

Robert Hensley
President
Diamond Helpers