Olgite

General Information:
 Chemical Formula:
Na(Sr,Ba)PO4
 Composition:
(Molecular Weight = 227.95 gm)
Barium 27.11 % Ba
Sodium 10.09 % Na
Strontium 21.14 % Sr
Phosphorus 13.59 % P 
Oxygen 28.08 % O 
 Empirical Formula:
NaSr0.55Ba0.45PO4
 Environment:
Nepheline syenite pegmatite.
 IMA Status:
Approved IMA 1980
 Locality:
Lovozero massif, Kola Peninsula, Russia.
 Name Origin:
Named for Olga Anisimovne-Vorobiova (1902-1974), Russian mineralogist.
Physical Properties:
 Color:
blue or blue green.
 Density:
3.94
 Habits:
Microscopic Crystals - Crystals visible only with microscopes., Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).,
 Hardness:
4.5 - Between Fluorite and Apatite
 Luster:
Vitreous (Glassy)
 Streak:
white
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