Nagashimalite

General Information:
 Chemical Formula:
Ba4(V+++,Ti)4Si8B2O27Cl(O,OH)2
 Composition:
(Molecular Weight = 1,474.64 gm)
Barium 37.25 % Ba
Titanium 3.25 % Ti
Vanadium 10.36 % V 
Silicon 15.24 % Si
Hydrogen 0.03 % H 
Chlorine 2.40 % Cl
Oxygen 31.46 % O 
 Empirical Formula:
Ba4V3+3TiSi8O28.5Cl(OH)0.5
 IMA Status:
Approved IMA 1980
Physical Properties:
 Cleavage:
None
 Color:
greenish black.
 Density:
4.08
 Hardness:
6 - Orthoclase
 Luster:
Sub Metallic
 Streak:
green
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