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Grading-Clarity:
describes the clearness or purity of a diamond. This is determined by the number, size, nature, and location of the internal (inclusions) and external (blemishes) imperfections.
Nitrogen and other elements trapped within a stone during its formation effect the ultimate color, and minerals embedded in a diamond during crystallization will influence the stone’s clarity.
These natural characteristics, called inclusions, make each stone unique; they are natures way of personalizing each diamond.
Gemologists even use these inclusions to determine a diamond's age. The fewer the inclusions, however, the more rare and precious the stone will be considered because nothing will interfere with the passage and reflection of light. The number, color, size, and position of any inclusions will specify a diamond's clarity, but most will not endanger its durability. To establish a diamond's clarity, it must be examined by a trained eye under a 10x magnification; the fewer the inclusions, the more valuable the diamond will be.
Be aware!
Two methods used to enhance the clarity grade given to a diamond are laser drilling and fracture filling.
Laser drilling is the process in which a laser is used to drill a tiny hole into a diamond and the black of the imperfection is then removed.
The second treatment is fracture filling. This method is not permanent and therefore not recommended.
BLEMISHES:
Abrasions:
tiny nicks on facet junctions or the culet; caused by wear or coming in contact with other diamonds.
Extra Facets:
small facets placed to remove imperfections; not part of the cutting style. (Not to be confused with Added Facets which are added symmetrically and are part of the cutting style).
Naturals:
part of the original crystal surface remaining on the polished stone, frequently in the area of the girdle.
Polish Lines and Marks:
tiny parallel lines or surface clouding left by irregular polishing or excessive heating during polishing, respectively.
Rough Girdle:
a grainy or pitted girdle surface usually caused by poor workmanship.
Surface Graining:
structural irregularities in crystal growth; may appear as faint lines, causing grooved or wavy surfaces and often cross facet junctions.
INCLUSIONS:
Bearding:
tiny feathers extending inward from a bruted girdle surface. (Bruting is the process of rubbing two diamonds together to achieve the rounded shape of the diamond).
Cavities and Chips:
large/deep openings, and small/shallow openings in the diamond's surface, respectively.
Clouds:
hazy or milky areas of many very small, usually crystalline inclusions.
Feathers:
cleavages or fractures often white and feathery in appearance. (There are 4 cleavage planes in diamond, which run in octahedral directions. Fractures are breaks along planes other than cleavage planes and may alternate with them to form step-like feathers).
Included Crystals:
mineral crystals, such as garnet or peridot, contained inside a diamond.
Indented Naturals:
natural rough surfaces that penetrate the stone and may distort the girdle outline.
Internal Graining:
regions of irregular crystal growth that may appear as milky or colored lines or streaks, or may be reflective.
Laser Drill Holes:
a tiny tube made by a laser; the surface opening may resemble a pit, while the tube usually resembles a needle.
Needles:
needle-shaped included crystals.
Pinpoints:
areas of minute, dot-like inclusions.
Twinning Wisps:
cloudy areas produced by distorted crystal growth.
Clarity::
All clarity grading is performed at 10-times magnification using a hand loupe or gemological microscope under both artificial daylight and darkfield illumination conditions. Reflected light is used to detect and evaluate blemishes and darkfield light for inclusions. It's the face-up view that usually sets the clarity grade, however the face-up, pavilion and table-to-culet views are all taken into consideration during grading.
Clarity grades are largely determined by the collective visual appearance that a stone's inclusions exhibit in relationship to the size and shape of the stone. It is the consideration of the size, position, number, color/contrast and nature of these inclusions, which leads to the final clarity grade.
Clarity Symbol Meaning Definition:
F - Flawless Free from all blemishes, or inclusions.
IF - Internally Flawless No inclusions visible at 10x magnification.
VVS1 - Very Very Slightly Included #1 Inclusions that are extremely difficult to detect at 10x.
VVS2 - Very Very Slightly Included #2 Inclusions that are very difficult to detect at 10x.
VS1 - Very Slightly Included #1 Minor inclusions, difficult to detect at 10x.
VS2 - Very Slightly Included #2 Minor inclusions, somewhat difficult to detect at 10x.
SI1 - Slightly Included #1 Noticeable inclusions, easy to detect at 10x.
SI2 - Slightly Included #2 Noticeable inclusions, very easy to detect at 10x.
SI3 - Slightly Included #3 Some inclusions may be seen with the unaided eye.
I1 - Included #1 Obvious inclusions. Somewhat easy to detect with the unaided eye.
I2 - Included #2 Obvious inclusions. Easy to locate with the unaided eye.
I3 - Included #3 Obvious inclusions. Very easy to detect with the unaided eye.
The above clarity grading scheme is in accordance with the GIA (Gemological Institute of America).
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