Natronambulite

General Information:
 Chemical Formula:
(Na,Li)Mn++4[Si5O14(OH)]
 Composition:
(Molecular Weight = 619.35 gm)
Sodium 2.60 % Na
Lithium 0.34 % Li
Manganese 35.48 % Mn
Silicon 22.67 % Si
Hydrogen 0.16 % H 
Oxygen 38.75 % O 
 Empirical Formula:
Li0.3Na0.7Mn2+4Si5O14(OH)
 Environment:
Found in the mine dump.
 IMA Status:
Approved IMA
 Locality:
Matsumaezawa ore body, Tahohata mine, Ivate Prefecture, Japan.
 Name Origin:
Named for its composition and for Matsuo Nambu (1917-), mineralogist, Tohoko University, Japan.
Physical Properties:
 Cleavage:
[100] Perfect, [001] Perfect
 Color:
pink orange.
 Density:
3.51
 Diaphaniety:
Transparent to Translucent
 Hardness:
5.5-6 - Knife Blade-Orthoclase
 Luster:
Vitreous (Glassy)
 Streak:
very pale orange
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