Mineral - Anatase
Anatase
Chemical Properties
Mineral Class
Oxides and Hydrxides
Toxicity
none
Formula
TiO₂
Unit Cell
a=3.78 c=9.51 Z=4
Physical Properties
Hardness
5.5 - 6
Streak
white
Density
Heavy (3,5-6)
Cleavage
Perfect after {001} and {011}
Fracture
conchoidal
Tenacity
Brittle
Optical Properties
Color
blackbrowngraygreengreen grey
Birefringence
0.073
Luster
Metallic,
Adamantine
Transparency
translucent,
transparent,
opaque
Pleochroism
Schwach
Geomineralogical Properties
Crystal System
tetragonal
Point Group
ditetragonal-dipyramidal - 4/m 2/m 2/m
Space Group
I4 1 /amd (141)
Habit
dipyramidal, tabular
Formation
Secondary from other titanium minerals in hydrothermal veins and veins; metamorphism; igneous; in carbonatites
Paragenesis
Twinning
Rare on {112}
Rarity
Common
Synonyms
Anatase
Composition
Elements
Mass
TiO₂
98.36
SnO₂
0.20
Al₂O₃
0.15
Fe₂O₃
0.84
CaO
0.15
Brazil (Deer et al. 1997)
Name and first discovery : Named in 1801 by Rene Just Haüy, from the Greek word "anatasis" which means "extension", due to the increased height of the dipyramidal anatase crystals in contrast to other tetragonal minerals.
Chemism : Polymorphic with Akaogiite, Brookite, Riesite, Rutile
Synonyms : Dauphinite, Hydrotitanite, Octahedrite, Octahedrite, Oisanit, Wiserin
Varieties : Gel-Anatase, Niobium-Anatase, Xanthitane
Abbreviation : Ant
literature
Deer, WA, Howie, RA, & Zussman, J. (Eds.). (1997). Rock-forming minerals: disilicates and ring silicates, volume 1B. Geological Society of London.