DIRK WIERSMA / SCIENCE PHOTO LIBRARY DIRK WIERSMA / SCIENCE PHOTO LIBRARY
Purple fluorite crystals. Fluorite, also called fluorspar, is a mineral form of calcium fluoride (CaF2). Many samples of fluorite fluoresce when exposed to ultraviolet (UV) light. The UV light is absorbed and the energy released in the form of visible light. The fluorescence of fluorite may be due to impurities such as yttrium (a transition metal) or organic matter in the crystal lattice. Therefore, the colour of visible light emitted can depend on where the original specimen was formed.
Model release not required. Property release not required.