Diamonds subjected to ultraviolet radiation (366 nm) can give rise to phenomena of fluorescence, which generally occur with blue-blue colors more or less intense, but, more rarely, also yellow, green, pink. It 'important to detect the fluorescence in the diamond, since the high intensity of the phenomenon influences the color of the gemstone. Since the amount of color of the diamond is detected with light sources that also emit ultraviolet rays, the diamonds with high fluorescence will undergo a change in apparent color, and specifically those with violet or blue fluorescence improve color while those that exhibit fluorescence color different can make it worse. Therefore, for the purchase of a diamond for investment, we recommend a fluorescence Weak or Nothing (which does not affect the color).

The fluorescence is evaluated according to the following scale:

• Nothing (None)
• Weak (Faint)
• Media (Medium)
• Strong (Strong)
• Very strong (Very strong)