General Information:
Chemical Formula:
NaCa2(Mg,Fe++)4Al(Si6Al2)O22(OH)2
Composition:
(Molecular Weight = 867.37 gm)
Sodium 2.65 % Na
Calcium 9.24 % Ca
Magnesium 8.41 % Mg
Aluminum 9.33 % Al
Iron 6.44 % Fe
Silicon 19.43 % Si
Hydrogen 0.23 % H
Oxygen 44.27 % O
Empirical Formula:
NaCa2Mg3Fe2+Si6Al3O22(OH)2
IMA Status:
Approved IMA 1978
Locality:
Pargas, Finland.
Name Origin:
Named after its locality.
Physical Properties:
Cleavage:
[110] Perfect, [010] Perfect
Color:
bluish green, brown, grayish black, light brown, or dark green.
Density:
3.069 - 3.181, Average = 3.12
Diaphaniety:
Transparent to translucent
Habits:
Tabular - Form dimensions are thin in one direction., ,
Hardness:
6 - Orthoclase
Luster:
Vitreous (Glassy)
Streak:
white
More details...