2820 West Market St., Akron, OH 44333 (330) 835-3000


Diamond Fluorescence

Fluorescence is the tendency of a diamond to emit a (soft) glow when exposed to ultraviolet light (UV light). The fluorescence effect is present in over 30% of diamonds and is an important consideration when buying a loose diamond.

When UV light strikes a diamond with fluorescent properties, the stone emits a glow. Most often blue, it can also be shades of green, yellow, white or red. Fluorescence can occur in different intensities. Gemological laboratories like the GIA rate diamond fluorescence on a scale from "None" to "Very Strong".


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 fluorescence, substantial color influence.

Is Fluorescence in a Diamond Good?

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 an MJO Jewelers jewelry expert to have it visually inspected before purchasing.

Let's Start a Conversation

Like all relationships, it starts with a simple conversation.