Grading Clarity (Chapter 11, Key Terms & Key Concepts) Flashcards
Visible to the unaided eye,
without magnification.
Eye-visible
Inclusions or
blemishes that establish the clarity grade of
a diamond.
Grade-setting characteristics
A map of a diamond’s inclusions,
blemishes, and facet arrangement.
Plot
Contrast between an inclusion and
its host gem.
Relief
The GIA Diamond Grading System provides a
universally accepted way to communicate
diamond quality.
Key Concept
The effect of clarity characteristics on the clarity
grade is based on their size, number, location,
relief, and nature.
Key Concept
Large inclusions usually have the greatest
influence on the clarity grade.
Key Concept
Because no two diamonds are alike, it’s difficult to
develop a precise description of any clarity grade
except Flawless
Key Concept
Blemishes very rarely have an effect on grades
lower than IF.
Key Concept
A clarity grade is usually determined by the
largest or most visible characteristics.
Key Concept
VS, SI, and I stones can have eye-visible
inclusions.
Key Concept
Accurate clarity grading includes consideration of
the size and shape of the diamond in relation to
its clarity characteristics.
Key Concept
Shows no inclusions and no blemishes when examined under 10x magnification.
Flawless (FL)
Shows only insignificant blemishes-no inclusions-when examined under 10x magnification.
Internally Flawless (IF)
Diamond contains minute inclusions that are difficult to see under 10x magnification.
Very Very Slightly Included (VVS)
Diamond contain minor inclisions that range from difficult (VS1) to somewhat easy (VS2) to see under 10x magnification.
Very Slightly Included (VS1 and VS2)
Diamond contains noticeable inclusions that are easy (SI1) or very easy (SI2) to see under 10x magnification.
Slightly Included (SI1 and SI2)
Diamond contains inclusions that are obvious under 10x magnification. (I1) are quite visible to the unaided eye. (I2) are easily visible and (I3) are extremely ease to see. They affect the stone’s durability.
Included (I1, I2, and I3)
The designation SI means
Slightly Included.
Diamonds with minute inclusions that range from difficult to very difficult to see under 10X are classified
VVS1 and VVS2
In most cases, the easier it is to see a clarity characteristic, the
lower the clarity grade.
A round brilliant-cut VVS diamond could have
a small pinpoint under a lower half facet.
Inclusions are usually most visible when they’re located
directly under the table.
A feather that reaches a bezel surface as well as the surface of the pavilion main directly under that bezel
should be plotted on both the crown and pavilion diagrams.
One factor used to determine the clarity grade of a diamond is an inclusion’s
location.
A stone with only a few extra facets on its pavilion that can’t be seen face-up should be graded
Flawless (FL)
On a plot, drawing a characteristic only in green indicates that it’s
a blemish
The more an inclusion differs in color from its host diamond,
the more obvious it is.
In a stone with these clarity characteristics, which would probably be the grade-setting characteristic?
feather.
Blemishes don’t usually affect the clarity grade in diamonds below
Internally Flawless (IF)
Inclusions or blemishes that establish the clarity grade of a diamond are collectively called
grade-setting-characteristics
VS1 and VS2 stones might have
minor included crystals and feathers.
Which of these would disqualify a stone from being graded IF?
Pinpoint
