unit
of measure
conversions
equivalences
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italiano
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english
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diamonds
clarity grading scale
Virtually
all natural diamonds contain identifying characteristics, many
of which are invisible to the naked eye.
Clarity is the degree to which a stone is free from marks called
blemishes and internal features called inclusions.
Inclusions normally have a greater impact on grade, value, beauty,
and durability than do blemishes.
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BLEMISHES:
Imperfections on the outside of a diamond
Chip:
A little piece missing, caused by wear or the cutting process.
Scratch: A line or abrasion.
Fracture: A crack on the diamond's surface.
Polishing lines: Fine lines on the stone's surface formed
during the polishing stage.
Natural: An unpolished part of the diamond.
Extra facets: Additional polished surfaces that shouldn't
be there and spoil the symmetry of a diamond.
Bearding: Very small fractures on an edge of the diamond.
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INCLUSIONS:
Imperfections inside a diamond.
Carbon: Black spots inside a stone.
Feather: Internal cracking.
Crystal: White spots inside a stone.
Pinpoint: Tiny spots, smaller than a crystal.
Cloud: A group of pinpoints, which may give the impression
of a single large inclusion.
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CLARITY:
All clarity grading is performed at 10X 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
grades of diamonds, as established by the Gemological Institute
of America (GIA):
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F
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Flawless
Free from all blemishes, or inclusions. |
Very
rare and very expensive.
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IF
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Internally
Flawless No inclusions visible at 10x magnification. |
Also
very rare and very expensive.
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VVS1
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Very
Very Slightly Included #1 Inclusions that are extremely difficult
to detect at 10x. |
Rare
and expensive.
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VVS2
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Very
Very Slightly Included #2 Inclusions that are very difficult
to detect at 10x. |
-
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VS1
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Very
Slightly Included #1 Minor inclusions, difficult to detect
at 10x. |
-
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VS2
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Very
Slightly Included #2 Minor inclusions, somewhat difficult
to detect at 10x. |
-
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SI1
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Slightly
Included #1 Noticeable inclusions, easy to detect at 10x.
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Good
quality.
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SI2
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Slightly
Included #2 Noticeable inclusions, very easy to detect at
10x. |
-
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SI3
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Slightly
Included #3 Some inclusions may be seen with the unaided eye. |
-
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I1
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Included
(imperfect) #1 Obvious inclusions. Somewhat easy to detect
with the unaided eye. |
Commercial
grade.
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I2
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Included
(imperfect) #2 Obvious inclusions. Easy to locate with the
unaided eye. |
-
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I3
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Included
(imperfect) #3 Obvious inclusions. Very easy to detect with
the unaided eye. |
Not
a pretty diamond.
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shape & carat | clarity
scale | color scale | cut
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