What is Diamond Fluorescence?

Diamond fluorescence is graded with descriptive terms that indicate the severity of the fluorescence—the GIA rates diamond fluorescence as either None, Faint, Medium, Strong, or Very Strong. During the grading process, the diamond will be compared to master diamonds of different fluorescence grades, until a match is found.

• None - The diamond has no fluorescence
• Faint (Faint Blue) -The diamond has minimal fluorescence
• Medium (Medium Blue) -The diamond has slightly noticeable fluorescence, and may appear hazy sunlight
• Strong (Medium Blue) -The diamond has noticeable fluorescence, and will appear hazy in sunlight
• Very Strong (Very Strong Blue) -The diamond has severely noticeable fluorescence, and will appear very hazy in
  sunlight

No, not all diamonds exhibit fluorescence. Only around 30% of diamonds do, which means that finding a diamond without fluorescence for your engagement ring is possible. We suggest opting for diamonds with no fluorescence or minimal fluorescence at most.

The desirability of diamond fluorescence depends on the diamond's color grade. In diamonds with high-quality color grades, fluorescence is considered undesirable. When exposed to ultraviolet light, such as sunlight, the diamond may emit a medium blue or strong blue light, resulting in a hazy appearance. However, in lower color grades, the blue light emitted can offset the diamond's yellow tinge. For diamonds with color grades I to M, some degree of fluorescence can be advantageous, although the stone may appear hazy in sunlight. Consider diamonds with color grades between D to F and either None or Faint fluorescence for a bright, clear, and icy-looking diamond.