Clarity is one of the fundamental attributes of a diamond and it is determined by the size, number position and nature of the inclusions, or internal characteristics of a stone.
The fewer inclusions or blemishes there are in or on the diamond, the higher the clarity grade and therefore value. The type of inclusions that affect the clarity can include scratches, blemishes, and pockets of air or non-diamond material inside or on the surface of a stone.
Accurate grading must be done with loose stones as jewellery mounts and settings can often conceal imperfections.
Diamond clarity is graded according to the size, number, positioning, nature and overall visibility of the inclusions and blemishes affecting a stone. As set out by the GIA*, the scale ranges from Flawless (FL/IF) where the diamond is completely free of inclusions, to Included (I3) where it has prominently visible inclusions.
*Other labs and certificates may differ from the precedence set by the GIA. Read more.
Inclusions and blemishes are structural imperfections which affect the clarity grading of diamonds. Inclusions are largely crystals of diamond or a foreign material that has formed within the stone affecting the internal composition, while blemishes are flaws which affect the stone’s surface. The size, number, colour, location, orientation, and visibility of inclusions and blemishes are all taken into account when evaluating the clarity of a diamond.
‘Fracture filled’ or ‘clarity enhanced’ diamonds are those whose fractures or cracks have been filled in with molten glass to restore and enhance their clarity. While they do make for a cheaper option, clarity enhanced diamonds are often too small or too low quality and therefore rarely certificated. Seventy Seven Diamonds do not offer any fracture filled diamonds; this section has been included merely for reference.