In everyday practice, most diamonds are viewed in daylight. In truth,
daylight is too variable and contains too much ultraviolet to be used
in the grading of stones. The light from most ordinary fluorescent lamps
contains too much ultraviolet for accurate color grading, and incandescent
bulbs are too yellow and too intense. The best grading lights are "daylight"
fluorescent lamps. They produce light that is fairly close to noon sunlight,
with minimal amounts of ultraviolet.
But, as was mentioned, most diamonds are not viewed under such consistent
lighting conditions when they are shown to friends and loved ones. For
this reason and others, diamonds are often given a fluorescence classification.
There are a vast many types of classifications, most of which will not
appear in our listing due to their negative effects on diamonds.
There are several, however, that can actually have a positive effect
on a diamond. To start, the optimum classification to have would be
"none" (N, NO or sometimes just blank) in most cases. A few other classifications
include "faint" or "faint blue" (F or FB). If just "faint" is given,
it is assumed that the color of the Fluorescence is blue. Such a classification
is actually beneficial to the look of diamonds in the lower color ranges
(H, I or below but really in J or lower). From there the classification
moves down to "medium" or "medium blue" (M or MB) and lower.
As we do not directly control the input of each stone, it is impossible
for us to control the codes that are used. We have, however, become
quite good at interpreting what the codes out there stand for. If you
have any questions about a specific code, please don't hesitate to Contact