While traveling from the basement of the world, projected into the lava of volcanoes and recovered under the ground in the driest areas, the diamond can collect breaks, small marks or tiny crystals. Its rating will be assigned based on the size, position and nature of those inclusions.
FL: Flawless - Pure with magnifying glass 10X
Surface and interior of the stone perfectly pure
May have: an extra facet, a raw witness (piece of uncut rough diamond), invisible growth lines, a laser inscription on the girdle
IF: Internally Flawless, perfect internal purity
Interior of the stone perfectly pure.
The difference with FL is a very slight surface imperfection, that a slight polishing can erase – it’s equivalent to a FL diamond barely scratched
VVS1 – VVS2 : Very very slightly Included
Very difficult to observe with a magnifying glass: Tiny inclusions, crystals, natural, etc.
Inclusion visible from the breech (not the table)
The difference between VVS1 and VVS2 is the position of inclusion, more or less close to the table or crown
VS1 – VS2 : Very slightly Included
Hard to observe with a magnifying glass: Very small crystals / small feathers / small cloud ...
Extremely discreet. The difference between VS1 and VS2 is the position of the inclusion, more or less close to the table or crown
SI1 – SI2 : Slightly Included
Inclusions easy (Si1) to very easy (Si2) to see with a magnifying glass, invisible to the naked eye.
Inclusions are difficult to see by the crown. Inclusions are of larger sizes and less well placed than in a VS stone
I1 – I2 – I3: Included
Obvious inclusions to see with a magnifying glass and the naked eye.
I2-I3 diamonds shows a certain decrease in the strength and brilliance
SI3 is an appellation for stones equivalent to I1 but is not recognized by certification laboratories