The 4C’s of Diamonds
The certificate is the passport from the polished diamond. It is determined by the 4C’s.
Carat:
The weight of a diamond is expressed in carats. One carat = 0.2 grams and one carat = 100 points.
Clarity:
Clarity refers to the presence ( or absence) of inclusions or blemishes within a diamond. “Blemishes” refers to surface imperfections, while “inclusions” speaks to unique characteristics inside the diamond.
Scale of purities:
IF (internally flawless)
No visible inclusion with a loupe 10x
VVS1-2 (very very slightly included)
Inclusions or blemishes very difficult to see with a loupe 10x
VS1-2 (very slightly included)
Inclusions or blemishes difficult to see with a loupe 10x
SI1-2 (slightly included)
Inclusions or blemishes easy to see with a loupe 10x
PI1 (Imperfect)
Inclusions or blemishes very easy to see with a loupe 10x
PI2 (Imperfect)
Inclusions or blemishes very easy to see with the naked eye
PI3 (Imperfect)
Big Inclusions or blemishes very easy to see with the naked eye
Colour
The majority of good quality diamonds are colourless to slightly yellowish. The colour grade is determined by comparison with a series of master stones, the best grade being colourless (Exc. White+ (D)).
Diamonds can also occur in all ranges of colours, from brownish to striking yellow, pink, purple, red, blue and green. These are called ‘fancy colours’.
Some diamonds react to ‘UV-light’ (black light) with a grading scale for the fluorescence from ‘nil’ to ‘strong’.
Cut
Proportions are determinative for the brilliancy and the ‘fire’ of a diamond. Symmetry describes the variation of the different parameters that define the proportions. Polish describes the finish of the facets.
Each of these individual parameters within the CUT, will be graded from EX till Poor make.
EX (excellent make)
VG (very good make)
G (good make)
POOR (poor make)