General Information:
Chemical Formula:
(Fe++,Mg)9Al4Cl18(OH)12·14(H2O) (?)
Composition:
(Molecular Weight = 1,634.03 gm)
Magnesium 3.35 % Mg
Aluminum 6.60 % Al
Iron 23.07 % Fe
Hydrogen 2.47 % H
Chlorine 39.05 % Cl
Oxygen 25.46 % O
Empirical Formula:
9(Fe2+0.75)9(Mg0.25)Al4Cl18(OH)12·14(H2O)
Environment:
Marine evaporite deposits.
Locality:
Hope, Hanover, Germany.
Name Origin:
Named after Zirkler, director of the Aschersleben potash works, Germany.
Physical Properties:
Cleavage:
[1011] Perfect, [1011] Perfect, [1011] Perfect
Color:
white or light gray.
Density:
2.6
Diaphaniety:
Transparent to translucent
Habits:
Massive - Uniformly indistinguishable crystals forming large masses., ,
Hardness:
3.5 - Copper Penny
Luster:
Vitreous - Dull
Streak:
white
More details...