General Information:
Chemical Formula:
(Li,Na)Mn++4[Si5O14(OH)]
Composition:
(Molecular Weight = 612.13 gm)
Sodium 0.94 % Na
Lithium 0.85 % Li
Manganese 35.90 % Mn
Silicon 22.94 % Si
Hydrogen 0.16 % H
Oxygen 39.21 % O
Empirical Formula:
Li0.75Na0.25Mn2+4Si5O14(OH)
Environment:
Forms a series with natronambulite.
IMA Status:
Approved IMA 1973
Locality:
Funakozawa mine, Kitakami Mountains, Iwate Prefecture, Japan.
Name Origin:
Named for Matsuo Nambu (1917-), mineralogist, Tohoko University, Japan.
Physical Properties:
Cleavage:
[001] Perfect, [100] Distinct, [010] Distinct
Color:
reddish orange brown.
Density:
3.51
Diaphaniety:
Transparent to Translucent
Hardness:
6.5 - Pyrite
Luster:
Vitreous - Adamantine
Streak:
light yellow
More details...