There is much information, not all of it correct, surrounding this characteristic. To better appreciate fluorescence and the role it plays in diamond grading, we must understand what it actually is and how it occurs.
When a diamond forms, trace elements (such as boron or nitrogen) may be present within the atomic structure. When exposed to ultra violet light, electrons in these trace elements absorb energy and they become excited and glow. This glow is what we see with our eye as fluorescence. It is naturally occurring and cannot be enhanced or removed from the diamond. Keep in mind that fluorescence is rarely visible in normal light and that diamonds are awarded a grading for their fluorescent character based on reactions after being exposed to ultraviolet light.
Diamond fluorescence is graded from none through to very strong. Solid Gold Diamonds will rarely hold a diamond in our inventory if it exhibits very strong fluorescence, and this is because a diamond that exhibits very strong fluorescence may appear oily or cloudy.