Manandonite

General Information:
 Chemical Formula:
Li2Al4[(Si2AlB)O10](OH)8
 Composition:
(Molecular Weight = 511.82 gm)
Lithium 2.71 % Li
Aluminum 26.36 % Al
Silicon 10.97 % Si
Boron 2.11 % B 
Hydrogen 1.58 % H 
Oxygen 56.27 % O 
 Empirical Formula:
Li2Al5Si2BO10(OH)8
 Environment:
Pegmatites.
 Locality:
Antandrokomby, near Mt. Bity on the Manandona River, Madagascar.
 Name Origin:
Named after its locality.
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
colorless or pearl white.
 Density:
2.89
 Diaphaniety:
Transparent to translucent
 Habits:
Micaceous - Platy texture with "flexible" plates., Pseudo Hexagonal - Crystals show a hexagonal outline., Massive - Lamellar - Distinctly foliated fine-grained forms.
 Hardness:
2.5-3.5 - Finger Nail-Copper Penny
 Luster:
Pearly
 Streak:
white
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