From The Gemology Project
|Chemical composition|| CaF2
|Habit||Octahedral, cubes, interpenetrant twins|
|Dispersion||Very low, 0.007|
|Fluorescence||Bluish-white, purple (LW)|
Fluorite may luminesce when heated. The stored energy from UV radiation is released if heated to a certain temperature and the effect depends on the amount of stored energy.
One can see this when a small amount of fluorite is placed on a teaspoon and heated over a candle for a few minutes (in a dark room).
Material from Telemark, Norway will show a blue-green thermoluminescence.
Color change fluorite has been reported with a change from blue to purple (much like some color change garnet).