Zirsinalite

General Information:
 Chemical Formula:
Na6(Ca,Mn,Fe++)Zr[Si6O18]
 Composition:
(Molecular Weight = 733.35 gm)
Sodium 18.81 % Na
Calcium 2.73 % Ca
Zirconium 12.44 % Zr
Manganese 2.25 % Mn
Iron 1.52 % Fe
Silicon 22.98 % Si
Oxygen 39.27 % O 
 Empirical Formula:
Na6Ca0.5Mn2+0.3Fe2+0.2ZrSi6O18
 Environment:
Alteration product of lomonosovite and barian lamprophyllite found in a drill core.
 IMA Status:
Approved IMA 1974
 Locality:
Mt. Koashva, Khibiny massif, Kola Peninsula, Russia.
 Name Origin:
Named for its composition (Zircon, Si, Na).
Physical Properties:
 Cleavage:
None
 Color:
colorless or pale yellow gray.
 Density:
2.9
 Diaphaniety:
Transparent
 Hardness:
5 - Apatite
 Luster:
Vitreous (Glassy)
 Streak:
white
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