The best
color is no color. Diamonds allow light to be reflected and
dispersed as a rainbow of color. This light dispersion, or color
flash, has no effect on the technical grading of color. The absolute
finest colorless stone carries a D rating, descending through each
letter of the alphabet to Z, designating a diamond of light yellow,
brown, or gray. This body color may be caused by the presence of
trace elements, such as nitrogen, within the atomic framework of the
carbon crystal. These trace elements are so minute that they are
scientifically measured in parts per million (ppm). As the body
color becomes more intense, the grade for color descends the scale.
These gradations are so minute and precise that discerning a single
grade (even by an expert) under less than ideal laboratory
conditions is extremely difficult. It is always best to compare
diamonds graded by either the Gemological Institute of America (GIA)
or the American Gem Society (AGS) for accurate color grading. When
directly comparing diamonds for color, most consumers are unable to
detect a difference unless they are at least two or three color
grades apart. We recommend selecting a diamond with a color grade of
K or better.
FANCY COLOR
It is often
surprising to learn that diamonds also occur by rare accidents of
nature in shades of pink, blue, green, amber, or even red. These
rarely occurring colors are referred to as fancies and are evaluated
by a different set of color standards. These standards take into
consideration various factors such as hue and saturation. Fancy
colored diamonds are the most expensive because of their extreme
rarity. Some fancy colors can cost hundreds of thousands of dollars
for diamonds of one carat or less!
FLUORESCENCE
Fluorescence is not directly related to a diamond’s
color. This separate characteristic refers to the diamond’s ability
to fluoresce under ultraviolet (UV) light. Our sun emits some UV
light, but it is usually not great enough to detect fluorescence.
The most common source of UV is a black light. When exposed to UV
light, many diamonds will give off a distinctive glowing blue
coloration. Although fluorescence may be displayed in various
colors, blue is the most common in diamonds. The fluorescence of a
diamond is defined by its intensity as either None, Faint, Medium,
Strong, or Very Strong. Although fluorescence is a characteristic
that can be measured, it is seldom an issue when selecting a
diamond.
