Mineral - Childrenite
Childrenite
Chemical Properties
Mineral Class
Phosphates
Toxicity
none
Formula
(Fe²⁺,Mn²⁺)Al[(OH)₂|PO₄]·H₂O
Unit Cell
a=10.40 b=13.39 c=6.92 Z=8
Physical Properties
Hardness
5
Streak
white
Density
Normal (2-3,5)
Cleavage
Indistinct after {100}
Fracture
uneven
Tenacity
Brittle
Optical Properties
Color
brown
Birefringence
0.042
Luster
Vitreous,
Resinous
Transparency
translucent,
transparent
Pleochroism
X= Gelb-Braun
Y= Rosa
Z= Rosa-Farblos
Geomineralogical Properties
Crystal System
orthorhombic
Point Group
orthorhombic-pyramidal - mm2
Space Group
Ccc2 (37)
Habit
prismatic, pyramidal, tabular
Formation
Through hydrothermal processes during the late stage of the cooling of granitic lithium-bearing pegmatites, usually through the alteration of primary phosphates under the influence of iron and manganese solutions.
Paragenesis
Twinning
Rarity
Rather rare
Synonyms
Childrenite
Composition
Elements
Mass
P₂O₅
29.92
Al₂O₃
21.43
FeO
28.56
MnO
3.11
CaO
0.65
Na₂O
0.37
H₂O
15.80
England (Palache et al. 1952)