Difference between revisions of "Fluorite"

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(=Optical phenomena)
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Material from Telemark, Norway will show a blue-green thermoluminescence.
 
Material from Telemark, Norway will show a blue-green thermoluminescence.
  
===Optical phenomena==
+
===Optical phenomena===
  
 
====Color change====
 
====Color change====
  
 
Color change fluorite has been reported with a change from blue to purple (much like some color change garnet).
 
Color change fluorite has been reported with a change from blue to purple (much like some color change garnet).

Revision as of 04:59, 20 September 2008

Fluorite
Chemical composition CaF2

Calcium fluoride

Crystal system Cubic
Habit Octahedral, cubes, interpenetrant twins
Cleavage Perfect, octahedral
Fracture Conchoidal
Hardness 4
Optic nature Isotropic
Refractive index 1.434
Birefringence Isotropic
Dispersion Very low, 0.007
Specific gravity 3.18
Lustre Poor vitreous
Fluorescence Bluish-white, purple (LW)
Fluorite


Diagnostics

Thermoluminescence

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.

Optical phenomena

Color change

Color change fluorite has been reported with a change from blue to purple (much like some color change garnet).