Mineral phase
IMA name
Stishovite
Class
non-silicate mineral
Compound type
oxide-hydroxide
Formula
$SiO_2$
Chemical formula
SiO2
Elemental formula
Si O2
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$Si$ Silicon element 1 constituent element main
$O$ Oxygen element 2 constituent element main
Chemical bonds
  Bond Number
$\geq Si-O-$ 6
Oxides
Formula $SiO_{2}$
Mass fraction (%) 100.0

Strunz

Class
oxides - hydroxides - arsenites (04)
Division
metal:oxygen = 1:2 and similar (04.D)
Family
with small cations: Silica family (04.DA)
Code
04.DA.40

Dana

Major class
oxides and hydroxides (III)
Class
simple oxides (04)
Type
with a cation charge of 4+ (A++++O2) (04.04)
Group
Rutile group (Tetragonal: P4/mnm) (04.04.01)
Code
04.04.01.09
Phase type
crystalline
Crystal system
tetragonal
Crystal class
ditetragonal-dipyramidal
Crystal class symbol
4/mmm (D4h)
Crystal spacegroup
P4(2)/mnm
Molar mass
60.08 $g/mol$
Density
4.35 (calc. 4.287) $g/cm^3$
State NTP
metastable solid - other solid
Phase transitions
Phase transition type Other phases Temperature - Pressure
solid-solid Coesite (metastable below 1.9 GPa) metastable below 7.9 GPa at room T, below 11 GPa at 1400°C
Phase transitions comments
the stable phase at NTP is $\alpha-Quartz$
Refringence type
uniaxial
Refringence sign
positive
Birefringence
0.027
Refraction index $n_o$ (w)
1.799 - 1.800
Refraction index $n_e$ (e)
1.826 - 1.845
Pure color
colorless
Color
colorless
Diaphaneity
transparent to translucent
Luster
vitreous