Difference between revisions of "Fluorite"

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[[image:Fluorite_barite_galena.jpg |left|framed|Fluorite with Barite and Galena <br /> Elmwood Mine, Carthrage, Tennessee ]]
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[[image:Fluorite_sphalerite_barite.jpg|left|framed| Fluorite with Sphalerite and Barite <br /> Elmwood Mine, Carthrage, Tennessee ]]
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===Thermoluminescence===
 
===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.<br />
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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.<br />
 
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).<br />
 
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).<br />
 
Material from Telemark, Norway will show a blue-green thermoluminescence.
 
Material from Telemark, Norway will show a blue-green thermoluminescence.

Revision as of 10:04, 26 September 2010

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 with Barite and Galena
Elmwood Mine, Carthrage, Tennessee
Fluorite with Sphalerite and Barite
Elmwood Mine, Carthrage, Tennessee


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).