Zussmanite

General Information:
 Chemical Formula:
K(Fe++,Mg,Mn)13[AlSi17O42](OH)14
 Composition:
(Molecular Weight = 2,147.17 gm)
Potassium 1.82 % K 
Magnesium 1.13 % Mg
Manganese 2.56 % Mn
Aluminum 1.26 % Al
Iron 28.61 % Fe
Silicon 22.24 % Si
Hydrogen 0.66 % H 
Oxygen 41.73 % O 
 Empirical Formula:
KFe2+11MgMn2+AlSi17O42(OH)14
 Environment:
Blue schist facies metamorphic rocks.
 IMA Status:
Approved IMA 1966
 Locality:
Laytonville quarry, 5 miles south of Laytonville, Mendocino Co., California.
 Name Origin:
Named for Jack Zussman (1924-), crystallographer and emeritus professor of geology, Manchester University, England.
Physical Properties:
 Cleavage:
[0001] Perfect
 Color:
light green.
 Density:
3.146
 Diaphaniety:
Translucent
 Luster:
Vitreous (Glassy)
 Streak:
white
More details...

ZUSSMANITE