Diamond Manual by Orsini - Antwerp Belgium

 

 

 

How is the quality of a diamond defined?

The quality of a diamond is determined by the four C's. Carat, Colour, Clarity and Cut.

What is a carat?

Diamonds are weighed in carats. One carat equals a fifth of a gram. The name "carat" comes from a seed of the carob tree. The seed was called "carubis" and had an approximate weight of about 0.2 grams.
 
.05
.10
.15
.20
.25
.50
.75
1.00
1.25
1.50
1.75

How is the color of a diamond measured?

Colour is graded by comparison to masterstones under standardized artificial light, equivalent to Northern daylight. Indicated colours are only meant to show the difference in shades.
 
D
E
F
G
H
I
J
exc.
white +
exc.
white
rare
white +
rare
white
white
slightly tinted
white

 
K
L
M
N-O
P-R
S-Z
tinted white
tinted colour

How is the clarity of a diamond measured?

A diamond is "loupe clean or internally flawless" if, after examination by an experienced grader with a loupe 10 x under normal light conditions, it has been found free of internal characteristics. The other clarity grades are determined by the size, position, brightness and number of internal characteristics. External characteristics and structure phenomena can be mentioned under "identification marks" or "comments". The lowest clarity grades on the scale (indicated by p for piqué) refer to inclusions that can be seen by an experienced grader with the naked eye.
 
LC/IF
VVS1
VVS2
VS1
VS2

SI1
SI2
P1
P2
P3

What are the possible shapes of a diamond?

Some common diamond shapes are shown below.
 
BRILLIANT
OVAL
MARQUISE
PEAR

HEART
PRINCESS
EMERALD