The Fluorescence is a reaction of the carbon of the diamond when exposed to the energy of different rays .
Fluorescence is the property that the diamond can change or generate a color by the excitation radiation such as X-rays or ultraviolet rays.
The excitement of a diamond with ultraviolet rays usually generates a blue or green color, orange, yellow or even pink.
A diamond when exposed to ultraviolet rays and remain dark has no fluorescence.
Some diamonds have a degree of strong fluorescence predominantly blue when exposed to the sunlight which can greatly alter their color, appearing whiter than actually they are.
Diamond-fluorescence standards are used to determine the degree of fluorescence.
30 to 40% of jewelery diamonds are with fluorescence. The rarest diamonds are those that are not fluorescent. An average fluorescence, strong or very strong drives a discount of the value of diamonds with color D to H. For tinted diamonds this discount is not applied.
The classification to express the degree of diamond fluorescence is:
None – Slight or Faint – Medium – Strong – Very Strong which you will find on the authenticity certificates.