in virtually all colors of the rainbow, from the "beautiful
violet" of the Hope diamond to shades of blue, brown,
gray, orange, etc. But colored diamonds are very rare
and precious. Chances are, all the diamonds you'll see in
your diamond shopping will be white or yellow, and the whiter
The yellow color
in diamonds comes from nitrogen, and as a rule, the more yellow
the stone, the less value it has. There's a good reason for
this. The yellowier the stone, the less sharp and sparkly
it appears. A whiter stone lets lighter pass through it, making
it sparkle and shine. The exception to the rule is the canary
diamond, which is a beautiful bright yellow and very expensive.
Some people are more sensitive to the color of diamonds. What
may appear slightly yellow to you may look clear to another
person, so it will take a higher color grade to satisfy you.
way to judge the color of a diamond is to use either a Gran
Fall Spectrum Colorimeter by Gem Instruments or compare it
to a master set.
HERE'S THE COLOR GRADING SCALE: D, E, F refers
to colorless and G, H, I refers nearly to colorless,
J, K, L indicated slightly yellow, M, N, O shows light
yellow P, Q, R, S, T, U, V, W, X shows darker yellow
and Z to Fancy colors.
there are several grades in each category, there are
slight differences between the letter grades. D is the
clearest and most valuable, X is a dingy yellow and
least expensive. Z grade-colored diamonds are the rarest
and most expensive. A diamond so saturated with nitrogen
that it becomes a deep, rich yellow is as rare as a
is a diamond's reaction to ultraviolet (UV) light. Some diamonds
glow in different colors under UV light, and the general rule
is to avoid them. If you put a diamond under UV light and
it glows strong blue, the diamond may look dull in the sunlight.
Diamonds with strong fluorescence may be worth up to 20% less
than diamonds which do not fluoresce. Faint fluorescence which
doesn't fog the diamond is OK.
Corresponding grading means matching clarity grades with color
grades. For every clarity grade, there's a color grade that
corresponds, or makes the best match in determining value.
Diamonds that have corresponding grading sell for higher prices
originally and they also appreciate in value more than diamonds
that don't, and therefore have higher resale value. Buying
a diamond with non-corresponding clarity and color grades
is like buying a pink Porsche: it's okay as long as you don't
try to resell it. The market for pink Porsches just isn't
as good as the market for, say, red Porsches.
The value of
a stone is always based on the lowest clarity or color grade
and its highest corresponding grade. When you don't correspond
the grades — say you buy high clarity and low color, or high
color and low clarity — you'll never get your money back for
the higher grade