Natrophilite

Natrophilite is a mineral with the chemical formula NaMnPO4. It is colored yellow. Its crystals are orthorhombic to dipyramidal. It is transparent to translucent. It is not radioactive. Natrophilite is rated 4.5 to 5 on the Mohs Scale.
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General Information:
 Chemical Formula:
NaMnPO4
 Composition:
(Molecular Weight = 172.90 gm)
Sodium 13.30 % Na
Manganese 31.77 % Mn
Phosphorus 17.91 % P 
Oxygen 37.01 % O 
 Empirical Formula:
NaMn2+(PO4)
Physical Properties:
 Cleavage:
[100] Good, [010] Indistinct
 Color:
yellow.
 Density:
3.41
 Diaphaniety:
Transparent to Translucent
 Habits:
Massive - Uniformly indistinguishable crystals forming large masses., ,
 Hardness:
4.5-5
 Luminescence:
Non-fluorescent.
 Luster:
Resinous
 Streak:
white
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