Mineral phase
IMA name
beta-Quartz
Secondary names
high-Quartz
CAS number
99439-28-8
Type
Class
silicate mineral
Compound type
tektosilicate
Chemical composition
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
Composition comments
Common impurities: traces of Al,Fe,Ti,Li,Ca,Mg, etc
Chemical bonds
  Bond Number
$\geq Si-O-$ 4
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.05

Dana

Major class
silicates (VIII)
Class
tectosilicate Si tetrahedral frameworks (75)
Type
SiO2 with [4] coordinated Si (75.01)
Group
Quartz group (75.01.03)
Code
75.01.03.01
Phase type
crystalline
Crystal system
hexagonal
Crystal class
trapezohedral
Crystal class symbol
622 (D6)
Crystal spacegroup
P6(4)22
Composition order
ordered
Molar mass
60.08 $g/mol$
Density
2.53 $g/cm^3$
State NTP
other solid
Phase transitions
Phase transition type Other phases Temperature - Pressure
solid-solid alpha-Quartz below 573°C at 1 bar, below ~1190°C at ~3.1 GPa
Refringence type
uniaxial
Refringence sign
unknown
Pure color
colorless
Color
colorless, brown, violet, gray, yellow
Diaphaneity
transparent to opaque
Luster
vitreous
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