Diamond fluorescence refers to the intensity of a coloured glow (usually blue) that is visible when a diamond is exposed to UV light. In some instances, diamonds with strong fluorescence may look milky and lifeless in daylight, but in most cases, the appearance of a diamond with strong fluorescence is rarely affected. Diamonds with none or a faint fluorescence are rarer than those with a strong or very strong fluorescence.
For diamonds with faint or no fluorescence, this does not affect the natural appearance of the diamond but a more fluorescent diamond glows in natural sunlight too and this can be perceived as being undesirable in a white diamond.
The degree of fluorescence can vary as around one-third of all diamonds show some fluorescence, with 95% exuding a blue colour – though green and yellow fluorescence diamonds can also be found, though much rarer than those with a blue hue.
Fluorescence is one indicator or grading variable for a diamond, but its presence does not necessarily affect how a diamond looks.
Fluorescence ranges from none through faint to medium, strong and very strong. A diamond with a strong or very strong fluorescence can sometimes have a milky appearance, although this is exhibited by less than 2% of diamonds with a strong or very strong fluorescence grade.
At Taylor & Hart, we inspect all of our diamonds and only offer diamonds that carry the maximum possible brilliance. In particular, we recommend fluorescence of “none” and “faint” because we believe your diamond should look beautiful in all lighting conditions and these two grades are least affected by fluorescence.