Diamond Fluorescence

Fluorescence, the effect ultraviolet (UV) light has on a diamond, is an important consideration when selecting a diamond. When UV light strikes a diamond with fluorescent properties, the stone emits a glow that is usually blue, but can also be shades of green, yellow, white, pink, orange, and red. The sources of fluorescence, boron and nitrogen, are the same mineral properties that lend to diamond color.

Fluorescence can occur in different intensities. Gemological laboratories rate the fluorescence of each diamond on a scale from "None" to "Very Strong". (Want to speak with a diamond expert? Call 866-737-0754 for expert advice on fluorescence.)

Diamond Fluorescence
None, Nil, Negligible
No fluorescence, no influence on color.
Faint, Slight
Weak fluorescence, not a significant influence on color (barely perceptible).
Average fluorescence, small influence.
Strong, Extremely Strong
Strong influence, substantial color influence.

The Effect Fluorescence has on a Diamond

Fluorescence can enhance or detract from the beauty of a diamond. The bluish tint can improve a lower-color diamond (J-M color rated) by cancelling out the faint yellow, resulting in a colorless appearance. However, in a very high-color diamond (D-F color rated), fluorescence may have the opposite effect.

In a small number of diamonds, the presence of strong fluorescence creates a hazy, milky, oily, or cloudy appearance. For this reason, very fluorescent diamonds can be valued lower than similar diamonds with fluorescent ratings of "None," "Faint," or "Medium." If you have selected a diamond with "Strong" or "Very Strong" fluorescence, please contact a Brilliance diamond and jewelry expert to have it visually inspected before purchasing

Guidance & Advice: Fluorescence

Depending on the color of a diamond, the fluorescence can either enhance or diminish the beauty of a diamond. When in doubt, always ask a gemologist to make sure the diamond fluorescence doesn’t affect the brilliance or sparkle.

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