Zunyite

Zunyite is a sorosilicate mineral, Al13Si5O20(OH,F)18Cl, composed of aluminium, silicon, hydrogen, chlorine, oxygen, and fluorine. It was discovered in 1884, and named for its discovery site, the Zuni mine in Colorado.
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(n.)
A fluosilicate of alumina occurring in tetrahedral crystals at the Zu/i mine in Colorado.
  

General Information:
 Chemical Formula:
Al13Si5O20(OH,F)18Cl
 Composition:
(Molecular Weight = 1,156.74 gm)
Aluminum 30.32 % Al
Silicon 12.14 % Si
Hydrogen 1.39 % H 
Chlorine 3.06 % Cl
Oxygen 49.79 % O 
Fluorine 3.28 % F 
 Empirical Formula:
Al13Si5(O)20(OH)16F2Cl
 Environment:
Metamorphosed highly aluminous shales
 Locality:
Postmasburg, South Africa.
Physical Properties:
 Cleavage:
[111] Good
 Color:
colorless, gray white, pink, or reddish white.
 Density:
2.88
 Diaphaniety:
Transparent
 Habits:
Crystalline - Fine - Occurs as well-formed fine sized crystals., ,
 Hardness:
7 - Quartz
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous (Glassy)
 Streak:
white
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