Lab Fluorite Faceted Loose Gems Blue Fluorescent Scintillator

These are loose calibrated faceted stones of blue glow lab fluorite, a wonderful mineral that is only rarely cut as gemstones. Natural fluorite has an incredible range of colors, not just purple and green but reds, yellows, blues, and more.  On top of that, fluorite can have strong fluorescence.  In fact, it can be so strong that fluorescence is named after fluorite.  This Europium-doped fluorite is grown for science - these crystals are valuable because they are extremely sensitive to many kinds of radiation (not just UV), so can be used as 'scintillators' for detecting the presence of x-rays.  Eu:Fluorite's glow is strong enough to change its color in direct sunlight, shifting from clear and colorless to a refreshing blue.  (So blue, that it can get too bright and overwhelms our digital camera, turning the photo purple!) You might be wondering "why are fluorite gems is so rare when it's so cool?" That's because fluorite is a really tricky material to cut.  It has low Moh's hardness