Book 27, Question 87
Why do some minerals glow under a special lamp?
Some minerals soak up invisible ultraviolet light and give back some of the energy as visible light, so they glow bright red, green, or blue.
This is called fluorescence. Fluorite is such a mineral, and it gave the effect its name. Scientists and museums use UV lamps in dark rooms to show glowing rocks. Never shine a UV lamp toward anyone's eyes.