There is common misconception that a diamond exhibiting fluorescence
under ultra violet light has some kind of colour defect or transparency
issue.
This NOT true at all. The naturally occurring fluorescence phenomenon
is a unique completely hidden feature, which is present to some level in
approximately 30% of all diamonds.
The effect is seen in Diamonds which have Carbon bonds which include boron.
Boron causes the diamond to glow when held under a powerful ultra violet light also known as blacklight.
The amount of boron in the Carbon bond making up the diamond will
determine the level of fluorescence. Fluorescence is rated by the
Laboratory as Very Strong, Strong, Medium, Faint, None. This relates to
the strength of the fluorescent glow under ultra violet light.
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