Agrellite

Agrellite (NaCa2[F|Si4O10]) is a mineral found in Quebec, Canada.
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General Information:
 Chemical Formula:
NaCa2Si4O10F
 Composition:
(Molecular Weight = 394.48 gm)
Sodium 5.83 % Na
Calcium 20.32 % Ca
Silicon 28.48 % Si
Oxygen 40.56 % O 
Fluorine 4.82 % F 
 Empirical Formula:
NaCa2(Si4O10)F
 Environment:
Alkalic igneous rocks of the Sheffield Lake complex.
 IMA Status:
Approved IMA 1973
 Locality:
Kipawa River, Villieu Township, Temiscaming County, Quebec, Canada.
 Name Origin:
Named for Stuart O. Agrell, British mineralogist, Cambridge University.
Physical Properties:
 Cleavage:
[110] Perfect, [110] Perfect, [010] Poor
 Color:
white, grayish white, or greenish white.
 Density:
2.88 - 2.9, Average = 2.88
 Diaphaniety:
Translucent
 Habits:
Lath - Shaped like a small, thin plaster lath, tabular (rectangular) in shape., ,
 Hardness:
5.5 - Knife Blade
 Luminescence:
Fluorescent.
 Luster:
Vitreous - Pearly
 Streak:
white
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