Diamonds are characterized by three distinctive factors: 1. Carat, 2. Colour, 3. Cut and Clarity.
1. Carat
Carat is the weight of the diamond. 1ct=1 carat=0,2 grams
2.Colour:Comparison of Colour Grading Systems.

GIA |
HRD |
UK |
|
COLOURLESS | D | Exceptional White + | Finest White |
E | Exceptional White | ||
F | Rare White + | Fine White | |
NEAR COLOURLESS |
G | ||
H | White | White | |
I | Slightly Tinted White | Commercial white | |
J | Top Silver Cape | ||
SLIGHTLY TINTED |
K | Tinted White | |
L | Silver Cape | ||
M | Tinted | Light Cape | |
N | |||
VERY LIGHT YELLOW |
O | Cape | |
P | |||
Q | |||
LIGHT YELLOW |
R | ||
S | |||
T | Dark Cape | ||
YELLOW | U | ||
V |
3. Cut
Most diamonds are cut with 58 facets, and a good cut, or make, has more scintillation, more sparkle. It is the work of a master cutter that allows the diamond to be cut in such a way as to permit the maximum amount of light to be reflected through the diamond. The most popular diamonds cuts are the following
Round Brilliant | Oval |
Marquise | Pear |
Heart | Emerald |
Baquette | Princess |
3. Clarity Grading Scale
Pure | Very Very Small Inclusion | Very Small Inclusion | Small Inclusion | Included | |||||
Internally Flawless | VVS1 | VVS2 | VS1 | VS2 | SI1 | SI2 | I1 | I2 | I3 |