GIA Diamond Essentials assignment 2
Questions and Correct Answers, With Complete
Verified Solution. 2024
Plot
a color-keyed diagram of a gemstone's significant clarity characteristics; it can be
modified for diamonds of any shape. when complete, a plot simplifies the task of finding
a diamond's clarity characteristics.
clarity is also known as ...
purity, or quality (in Europe)
Clarity characteristics form appear at different stages:
during or after formation, can be also caused by cutting or setting process, or even
occur when the diamond is being worned.
loupe
a small portable magnifying lens used by jewelers and watchmakers; from 4X to 30X;
binocular microscope
A tabletop magnifier with two eyepieces
10X
10X magnification is the standard clarity grading.
Graining 晶纹
Sometimes as a crystal grows it develops irregularities in its atomic structure. When that
happens, it forms a clarity characteristic called graining. Graining often looks like faint
lines or streaks. Sometimes the lines are parallel, and sometimes they intersect.
break/feather (cleavage and fracture)
Cleavage is a break parallel to the weakest direction in the gem's structure. It
sometimes has a step-like appearance. A fracture is a break in any other direction. In
the trade, cleavages and fractures are generally called feathers. That's because they
have a white, feathery appearance.
inclusion types
Clarity Grading Factors
size; number; location (position); relief (the contrast between the inclusion and the
diamond); nature (type of inclusion).
one or two large inclusions usually set the grade; a reflector can lower the grade more
than non-reflectors (a reflector in the pavilion can make it looks like many...); inclusions
right under the table are more visible than other locations like under the bezel facets or
near the girdle;
Bruting/round up/girdling
Forming the basic face-up outline of a round or rounded-shape diamond to prepare it for
faceting; can cause bearding
Bearding
Small feathers that extend from the surface of the girdle into the stone [inclusion]
Natural (N)
, a portion of the original surface of a rough diamond left on a fashioned stone; usually on
or near the girdle. [blemish]
Chip (Ch)
A shallow opening that occurs at a girdle edge, facet junction, or culet; is caused by
damage to the stone surface [inclusion]
Polish Lines (PL)
fine parallel grooves and ridges left by polishing; do not pass facet junction, transparent
or white [blemish]
Bruise (Br)
A tiny area of impact accompanied by very small, root-like feathers visible at 10X
magnification; typically occurs at a facet junction. [inclusion]
Cavity (Cav)
An opening on the surface that occurs when part of a feather breaks away, or when a
crystal drops out/is forced out, typically during polishing. [inclusion]
Cloud (Cld)
Many tightly grouped pinpoints that might be too small to distinguish individually at 10X
but together have a hazy appearance. [inclusion]
Crystal (Xtl)
A mineral crystal contained in a diamond. [inclusion]
Etch Channel (EC) 凹蚀管
An angular opening that starts at the surface and extends into the stone, often with
striations perpendicular to its length [inclusion]
Feather (Ftr)
General trade term for a break in a gemstone. Often white and feathery in appearance.
[inclusion]
Indented Natural (IN)
A portion of the rough's original surface, or skin, that dips below the polished diamond's
surface, with depth visible at 10X [inclusion]
Internal Graining (IG)
Lines, angles, or curves that might appear whitish, colored, or reflective or affect
transparency at 10X; caused by irregularities in crystal growth [inclusion]
Internal Laser Drilling (ILD)
Laser drilling within a diamond that doesn't reach the surface; not plotted. [inclusion]
Knot (K)
An included diamond crystal that extends to the surface after fashioning. [inclusion]
Laser Drill-hole (LDH)
A tiny, surface-reaching tunnel produced by a laser light beam. [inclusion]
Needle (Ndl)
A thin, elongated crystal that looks like a tiny rod at 10X. [inclusion]
Patch of Color (Patch)
Naturally occurring radiation stain left on a polished diamond. Typically a blemish, but
can be an inclusion if it extends into the stone when viewed at 10X
Pinpoint (Pp)
A very small included crystal that looks like a tiny dot at 10X. [inclusion]
Twinning Wisp (TW)
Questions and Correct Answers, With Complete
Verified Solution. 2024
Plot
a color-keyed diagram of a gemstone's significant clarity characteristics; it can be
modified for diamonds of any shape. when complete, a plot simplifies the task of finding
a diamond's clarity characteristics.
clarity is also known as ...
purity, or quality (in Europe)
Clarity characteristics form appear at different stages:
during or after formation, can be also caused by cutting or setting process, or even
occur when the diamond is being worned.
loupe
a small portable magnifying lens used by jewelers and watchmakers; from 4X to 30X;
binocular microscope
A tabletop magnifier with two eyepieces
10X
10X magnification is the standard clarity grading.
Graining 晶纹
Sometimes as a crystal grows it develops irregularities in its atomic structure. When that
happens, it forms a clarity characteristic called graining. Graining often looks like faint
lines or streaks. Sometimes the lines are parallel, and sometimes they intersect.
break/feather (cleavage and fracture)
Cleavage is a break parallel to the weakest direction in the gem's structure. It
sometimes has a step-like appearance. A fracture is a break in any other direction. In
the trade, cleavages and fractures are generally called feathers. That's because they
have a white, feathery appearance.
inclusion types
Clarity Grading Factors
size; number; location (position); relief (the contrast between the inclusion and the
diamond); nature (type of inclusion).
one or two large inclusions usually set the grade; a reflector can lower the grade more
than non-reflectors (a reflector in the pavilion can make it looks like many...); inclusions
right under the table are more visible than other locations like under the bezel facets or
near the girdle;
Bruting/round up/girdling
Forming the basic face-up outline of a round or rounded-shape diamond to prepare it for
faceting; can cause bearding
Bearding
Small feathers that extend from the surface of the girdle into the stone [inclusion]
Natural (N)
, a portion of the original surface of a rough diamond left on a fashioned stone; usually on
or near the girdle. [blemish]
Chip (Ch)
A shallow opening that occurs at a girdle edge, facet junction, or culet; is caused by
damage to the stone surface [inclusion]
Polish Lines (PL)
fine parallel grooves and ridges left by polishing; do not pass facet junction, transparent
or white [blemish]
Bruise (Br)
A tiny area of impact accompanied by very small, root-like feathers visible at 10X
magnification; typically occurs at a facet junction. [inclusion]
Cavity (Cav)
An opening on the surface that occurs when part of a feather breaks away, or when a
crystal drops out/is forced out, typically during polishing. [inclusion]
Cloud (Cld)
Many tightly grouped pinpoints that might be too small to distinguish individually at 10X
but together have a hazy appearance. [inclusion]
Crystal (Xtl)
A mineral crystal contained in a diamond. [inclusion]
Etch Channel (EC) 凹蚀管
An angular opening that starts at the surface and extends into the stone, often with
striations perpendicular to its length [inclusion]
Feather (Ftr)
General trade term for a break in a gemstone. Often white and feathery in appearance.
[inclusion]
Indented Natural (IN)
A portion of the rough's original surface, or skin, that dips below the polished diamond's
surface, with depth visible at 10X [inclusion]
Internal Graining (IG)
Lines, angles, or curves that might appear whitish, colored, or reflective or affect
transparency at 10X; caused by irregularities in crystal growth [inclusion]
Internal Laser Drilling (ILD)
Laser drilling within a diamond that doesn't reach the surface; not plotted. [inclusion]
Knot (K)
An included diamond crystal that extends to the surface after fashioning. [inclusion]
Laser Drill-hole (LDH)
A tiny, surface-reaching tunnel produced by a laser light beam. [inclusion]
Needle (Ndl)
A thin, elongated crystal that looks like a tiny rod at 10X. [inclusion]
Patch of Color (Patch)
Naturally occurring radiation stain left on a polished diamond. Typically a blemish, but
can be an inclusion if it extends into the stone when viewed at 10X
Pinpoint (Pp)
A very small included crystal that looks like a tiny dot at 10X. [inclusion]
Twinning Wisp (TW)
