Magnesiosadanagaite

General Information:
 Chemical Formula:
(K,Na)Ca2(Mg,Fe++,Al,Ti)5[(Si,Al)8O22](OH)2
 Composition:
(Molecular Weight = 900.44 gm)
Potassium 3.26 % K 
Sodium 0.64 % Na
Calcium 8.90 % Ca
Magnesium 6.75 % Mg
Titanium 1.33 % Ti
Aluminum 8.24 % Al
Iron 9.30 % Fe
Silicon 18.71 % Si
Hydrogen 0.22 % H 
Oxygen 42.64 % O 
 Empirical Formula:
K0.75Na0.25Ca2Mg2.5Fe2+1.5Al0.75Ti0.25(Si6Al2O22)(OH)2
 Environment:
Banded skarns and recrystallized limestones.
 IMA Status:
Approved IMA
 Locality:
Myojin Island, Ehime Prefecture, Japan.
 Name Origin:
Named for the composition and for Ryoichi Sadanaga (1920-), professor emeritus, University of Tokyo.
Physical Properties:
 Cleavage:
[110] Perfect
 Color:
dark brown or black.
 Density:
3.27
 Diaphaniety:
Transparent to Translucent
 Hardness:
6 - Orthoclase
 Luster:
Vitreous (Glassy)
 Streak:
light brown
More details...

General Information:
 Chemical Formula:
(K,Na)Ca2[Mg3(Al,Fe+++)2][Si5Al3O22](OH)2
 Composition:
(Molecular Weight = 872.23 gm)
Potassium 3.36 % K 
Sodium 0.66 % Na
Calcium 9.19 % Ca
Magnesium 8.36 % Mg
Aluminum 10.05 % Al
Iron 4.80 % Fe
Silicon 19.32 % Si
Hydrogen 0.23 % H 
Oxygen 44.02 % O 
 Empirical Formula:
K0.75Na0.25Ca2Mg3Al1.25Fe3+0.75(Si6Al2O22)(OH)2
 IMA Status:
Proposed IMA (Dana # Added)
 Name Origin:
Named for the composition and for Ryoichi Sadanaga (1920-), professor emeritus, University of Tokyo.
More details...