Common Jewelry Terms
- Imperfections found on the surface of a Diamond.
- describes how well a diamond reflects white light.
- is a unit of weight measurement used for weighing
diamonds. One carat equals 0.2 grams or 200 milligrams. 142
carats equals one (1) avoirdupois ounce.
- measures the degree of visibility of surface blemishes
or internal inclusions of a diamond.
- Minor inclusion appearing milky rather than dark or ash
like, only minimally detracting from the stone's appearance.
- measures the tint or internal color of a diamond,
ranging from colorless to light brown or yellow.
- refers to the upper domed surface above the girdle of a
cut diamond. The angle of the crown between the girdle and
the table is considered acceptable at between 30.0-37.0
degrees. Crown height is considered acceptable when between
11.0-16.2% of the girdle's diameter.
- CT or CTS
- Stands for total carat weight of singular stone.
- Indicates the total diamond carat weight of the jewelry
- is the end point of the pavilion, finer being considered
better, however a sharp point is susceptible to chipping.
- refers the shape (round, square, emerald, pear, oval,
marquis, etc.) and proportions of a cut diamond.
- is the vertical height of the diamond from the table to
the cutlet. Considered acceptable when between 57.0 to 65.0%
of the girdle's diameter.
- Eye Clean
- Diamond appears to be free of surface blemishes and
inclusions to the naked eye. Diamonds graded SI-2 or better
will appear to be eye clean.
- are the small polished plane surfaces of a cut gem
stone. A brilliant (round), full-cut diamond has 56 facets,
while stones under 3 points can have as few as 16 (single
- Refers to the quality of the diamond's polish and
- Describes the intensity and diversity of the light
spectrum (rainbow colors) emanating from a diamond.
- Refers to the emission of photoluminescence by a diamond
detectable under a black light. Blue fluorescence can
enhance a diamonds color, but other colors are considered
- refers to the edge where the crown and pavilion of a cut
diamond meet, marking the maximum diameter or width of the
diamond. A girdle width of between 2.0-4.0% of the girdle's
diameter is considered acceptable. Too sharp or thin a
girdle increases the likelihood of chipping.
- Girdle Diameter
- is the diameter of the diamond at the point where the
crown and pavilion meet. Other dimension characteristics of
a cut diamond are expressed as a percentage (%) of the
- refers to the internal defects of a diamond, appearing
as ash like flakes, cracks, clouds, or other imperfections.
- Describes the diamond's cut and proportions.
- is the tapered underhalf or base of a cut diamond below
the girdle. The angle of the pavilion from the girdle to the
cutlet is considered acceptable when between 39.7-41.7
degrees. Pavilion depth is considered acceptable when
between 41.5-45.5% of the girdle's diameter.
- is a unit of weight equal to 1/100 of a carat, 100
points equaling one carat, and written as 1.00 carat.
- Describes the luster of a diamond's exterior finish.
- Describes if the diamond is true to its desired shape
and is in balanced proportions.
- is the flat top surface of a cut diamond. Table diameter
is considered acceptable when between 51.4-66.0% of the