Grading...the 4 C's
color is graded from D-F (colorless) through G-J (near colorless), K-M
(faint yellow), N-R (very light yellow) down to S-Z (light yellow). In
the K-R range you sometimes get a very light brown called
"champagne" and a darker brown called "cognac", both
very attractive. Even when a stone has a visible tint, such as an M
color, it can still be very lovely if it has good clarity and cut.
also come in a wide variety of other colors, including red, blue, green
and a bright yellow known as "canary." These are graded as Z+
and are known as fancy diamonds. Ones with good color are very rare and
can sell for much more per carat than white diamonds.
is very common for diamonds to be formed in nature with slight
imperfections. These are known as inclusions and can come in many forms,
including tiny white points, dark dots of carbon, or feathery cracks.
The fewer inclusions, the more the stone is worth. A diamond's clarity
ranking is determined by the number, size, type and placement of the
grading ranges from FL (flawless) through VVS (very, very slight
imperfection), VS (very slight imperfection), SI (slight imperfection),
I1 (imperfect, can be seen with the naked eye) to I3, commercial or
cut properly a diamond reflects the light back up through the center of
the stone to give its characteristic sparkle. A poorly cut stone looks
flat like a piece of glass. The quality of the cut is call the
"make", and it ranges from Class 1-Ideal Cut (round diamonds
only), Class 2-Well Cut, Class 3-Average Cut to Class 4-Below Average
Cut. There are six key factors that determine a diamond's class, but
they need to be understood because diamond reports usually give the
factors but do not classify them.
size really mean everything? Learn about caret weight of diamonds.
data on this page and other diamond grading pages is credited to the
book, Jewelry & Gems, The Buying Guide by Antoinette L.
Matlins, PG & A.C. Bonanno, FGA, PG, ASA published by GemStone
Press, Woodstock, Vermont.