Mineral - Cafarsite
Cafarsite
Chemical Properties
Mineral Class
Arsenates
Toxicity
middle
Formula
(Ca,Na)₁₉Ti₈Fe³⁺₄Fe²⁺₄(AsO₃)₂₈F
Unit Cell
a=15.98 Z=4
Physical Properties
Hardness
5.5 - 6
Streak
brown
Density
Heavy (3,5-6)
Cleavage
Fracture
conchoidal
Tenacity
Brittle
Optical Properties
Color
blackbrown
Birefringence
Luster
Metallic
Transparency
opaque
Pleochroism
Geomineralogical Properties
Crystal System
isometric
Point Group
diploidal - 2/m 3
Space Group
Pn 3 (201)
Habit
dodecahedron, Octahedron, Cube
Formation
Metasomatism
Paragenesis
Twinning
Rarity
Rarely
Synonyms
Cafarsite
Composition
Elements
Mass
As₂O₅
60.0
TiO₂
8.5
Fe₂O₃
11.0
MnO
5.0
CaO
13.0
H₂O
2.4
Switzerland (Graeser 1966)