Reederite-(Y)

General Information:
 Chemical Formula:
Na15Y2(CO3)9(SO3F)Cl
 Composition:
(Molecular Weight = 1,197.26 gm)
Sodium 28.80 % Na
Yttrium 14.85 % Y 
Carbon 9.03 % C 
Sulfur 2.68 % S 
Chlorine 2.96 % Cl
Oxygen 40.09 % O 
Fluorine 1.59 % F 
 Empirical Formula:
Na15Y2(CO3)9(SO3)FCl
 Environment:
Inclusions in a trona-filled vug in a sodalite xenolith in syenite.
 IMA Status:
Approved IMA
 Locality:
Poudrette Quarry, Mont Saint-Hilaire, Rouville County, Quebec, Canada.
 Name Origin:
For Dr. Richard J. Reeder, currently co-editor of the American Mineralogist.
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
yellow or orange brown.
 Density:
2.91
 Diaphaniety:
Transparent
 Habits:
Blocky - Crystal shape tends to be equant (e.g. feldspars)., Granular - Generally occurs as anhedral to subhedral crystals in matrix.,
 Hardness:
3-3.5 - Calcite-Copper Penny
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous (Glassy)
 Streak:
white
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