This Simple Trick Reveals Real Diamonds! Fluorescence in diamonds is an effect that occurs when certain trace elements within the crystal structure interact with ultraviolet light. In most natural diamonds, this effect is caused by nitrogen impurities that replace some of the carbon atoms in the diamond’s lattice. When ultraviolet light hits the diamond, these nitrogen atoms absorb high energy photons and release part of that energy as visible light, most often blue. The color and intensity of f