Mineral - Steenstrupine-(Ce)
Steenstrupine-(Ce)
Chemical Properties
Mineral Class
Silicates
Toxicity
radioactive
Formula
Na₁₄Ce₆Mn²⁺(Mn³⁺Fe³⁺)₂(Zr,Th)(Si₆O₁₈)₂(PO₄)₇(OH)₂·3H₂O
Unit Cell
a=10,46 c=45,48 Z=3
Physical Properties
Hardness
4 - 5
Streak
whitebrownbrown white
Density
Cleavage
nd
Fracture
conchoidal
Tenacity
nd
Optical Properties
Color
blackbrown
Birefringence
0.004
Luster
Vitreous,
Greasy
Transparency
opaque
Pleochroism
Geomineralogical Properties
Crystal System
trigonal
Point Group
Space Group
Habit
coarse, dipyramidal, massive, Rhombohedron, tabular
Formation
Magmatisch, in Pegmatiten von Nephelin-Syeniten
Paragenesis
Twinning
Rarity
Rarely
Synonyms
Steenstrupine-(Ce)
Composition
Elements
Mass
SiO₂
26,72
ZrO₂
3,92
ThO₂
2,13
Y₂O₃
0,36
(Ce,La)₂O₃
29,60
Fe₂O₃
2,67
Mn₂O₃
2,51
Nb₂O₅
4,37
MnO
6,60
MgO
0,31
CaO
2,33
Na₂O
11,23
H₂O
3,45
P₂O₅
8,19
F
1,23
Grönland
Groups and Members
Steenstrupin-Gruppe