| F-J | K-O |
P-T | U-Z
Shape | Feather
Thickness | Heart-Shape
Cut | HRD
flat planes or surfaces on a diamond. Each facet must be cut in exact geometric
relation to the other facets to create the most fire and brilliance.
Shape: any diamond shape other than round.
a type of inclusion that occurs naturally in diamonds. Feathers are simply small
fractures, shaped like a bird's feather, that touch the stone's surface. Feathers
are noted on the diamonds grading report.
the qualities imparted to a diamond by the skill of the diamond cutter. The term
"finish" covers every aspect of a diamond's appearance that is not a
result of the diamond's inherent nature when it comes out of the ground. When
a gemologist grades finish, he considers the execution of the diamond's design,
the precision of its cutting details, and the quality of its polish. On a diamond's
grading report, you will see the diamonds finish, graded according to two
separate categories: polish and symmetry.
when exposed to ultraviolet light, small percentages of diamonds fluorescence,
or emit light. Fluorescence does not necessarily affect a diamond's value; however,
it is listed on a diamond grading report as None, Faint, Slight, Medium, Strong
or Extreme. Some reports also list the colour of the fluorescence (e.g. blue,
yellow, white, etc.). Be aware that stones which give off blue light may actually
be more valuable, since the blue light can make them appear "whiter"
in daylight or fluorescent lighting.
the outermost edge of a diamond that sits in the setting, separating the upper
and lower sections of the stone. The girldle varies in thickness, depending on
how it was faceted by a cutter during manufacturing.
Thickness: a diamond's girdle, or outermost edge that separates the upper
and lower sections of the stone, varies in thickness depending on how it was faceted
by a cutter during manufacturing. If the girdle is too thin, or the stone may
chip. If it is too thick, the diamonds brilliance may be reduced. A properly
cut girdle should be even all the way around. If the girdle appears to be a wide
band around the diamond, it's probably too thick. If you can hardly see it, it's
probably too thin.
a type of fancy diamond cut, which is cut to resemble the popular Valentine's
'De Hoge Raad voor Diamant' is a prestigious independent European gemological
certification laboratory based in Antwerp, Belgium that began grading diamonds
and providing grading reports in 1976. The HRD does not sell diamonds, but acts
as a consultant in the grading of precious gems. It is important to note that
a grading report provided by any gemological laboratory is NOT a statement of
the monetary value of a particular stone (like an appraisal), but a professional
opinion that evaluates only its quality.
International Gemological Institute. One of the largest, most respected
gemological institutions in the world. The IGI is an independent laboratory whose
trained gemologists grade diamond quality and provide a grading report along with
each stone they grade. The IGI does not sell diamonds, but acts as a consultant
in the grading of precious gems, as well as provides educational courses in diamonds
and diamond grading. Founded in Antwerp in 1975, the IGI has offices in Antwerp,
New York, Bangkok and Mumbai.
a small cloud, feather, crystal or other blemish that occurs naturally inside
or on the surface of diamonds. The fewer inclusions, the more rare the diamond
and the greater its value. A truly flawless diamond is extremely rare.
Setting: invisible-set diamonds are placed very closely together, with
the metal concealed underneath the diamonds, giving the appearance of a continuous,
uninterrupted surface. Since the metal is not seen, this type of setting is an
excellent way to showcase the brilliance of the diamonds themselves. It also allows
an increased amount of light to enter the stone (and, thus give off more brilliance),
since there are no prongs or bezels impeding the light's entry.
on diamonds: A-E | F-J
| K-O | P-T