Diamond Basics
Diamond Fluorescence: Good or Bad?
About a third of diamonds glow under UV light. Usually harmless — sometimes even beneficial.
What it is
Trace nitrogen or boron causes a visible glow, usually blue, under ultraviolet light. Reports grade it None, Faint, Medium, Strong or Very Strong.
Impact on appearance
Medium blue fluorescence can make faintly yellow stones look whiter. Very strong fluorescence occasionally causes a hazy look in high colour grades, so always view the stone in daylight.
Verification tools & references
Every Riakoob piece arrives certified, insured and covered by our 12-month value promise.
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