Color
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. 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.
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!
Fluoresence
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.
