Diamond Florescence

Fluorescence is the glow that can be seen sometimes when an object emits visible light. Certain diamonds fluoresce to some extent when subjected to ultraviolet (UV) rays from sources like the sun and fluorescent lamps, and they occasionally emit a yellow or orange light. When the UV light source is turned off, these diamonds quit fluorescing. Although some diamonds fluoresce when exposed to UV light sources, the overall fluorescence of diamonds should not be a major factor when buying a diamond because its effects are minimal.


(Diamonds seen with a UV lamp)

diamond under normal light

(Diamonds seen under normal lighting)

Do all diamonds exhibit fluorescence?

Roughly 30% of diamonds exhibit fluorescence to some degree.

Does fluorescence affect the value or appearance of a diamond?

Several industry experts believe that blue fluorescence in diamonds can make color grade I to M diamonds appear more colorless under UV light, such as sunlight. This advantage may enable near colourless to faintly yellow diamonds with extremely strong to medium bluish fluorescence to be significantly more expensive per carat than similar diamonds without fluorescence.

On the other hand, diamonds with bluish fluorescence in the D to H color range are often deemed less desirable by the trade. To put it another way, diamonds with these color grades may appear fuzzy or oily if the intensity of the bluish fluorescence is particularly high. Even yet, not all diamonds with very strong blues fluorescence have an oily appearance. On the plus side, however, they can be more affordable than diamonds without blue fluorescence.

Is diamond fluorescence good or bad?

The beauty of a diamond is in the eye of the beholder, so some people may see the fluorescence and others may not. Some people might like it or not. Actually, fluorescence shouldn’t be a big deal when buying diamonds because it doesn’t degrade the diamond’s structure or have any other bad effects on it.