Mineral phase
IMA name
Lizardite 1T
Secondary names
Orthoantigorite
Type
Class
silicate mineral
Compound type
phyllosilicate
Comments
2 others known polytypes: $2H_1$: hexagonal 6mm (P6(3)cm), 6A: ?
Chemical composition
Formula
$Mg_3.Si_2O_5(OH)_4$
Chemical formula
Mg3Si2O5(OH)4
Elemental formula
Mg3 Si2 O9 H4
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$Mg$ Magnesium element 3 constituent element main
$Si$ Silicon element 2 constituent element main
$O$ Oxygen element 9 constituent element main
$H$ Hydrogen element 4 constituent element main
Chemical functions
  Function Number
$(OH)^-$ 4
Chemical bonds
  Bond Number
$O^--H$ 1
Oxides
Formula $MgO$ $SiO_{2}$ $H_{2}O$
Mass fraction (%) 43.63 43.36 13.0

Strunz

Class
silicates (09)
Division
phyllosilicate (09.E)
Family
Phyllosilicates with kaolinite layers (09.ED)
Code
09.ED.15

Dana

Major class
silicates (VIII)
Class
phyllosilicate sheets of six-membered rings (71)
Type
with 1:1 layers (71.01)
Group
Serpentine group (Lizardite subgroup) (71.01.02b)
Code
71.01.02b.02
Phase type
crystalline
Crystal system
trigonal
Crystal class
ditrigonal-pyramidal
Crystal class symbol
3m (C3v)
Crystal spacegroup
P31m
Molar mass
277.11 $g/mol$
Density
2.55 - 2.6 $g/cm^3$
State NTP
solid
Refringence type
biaxial
Refringence sign
negative
Birefringence
0.0055 - 0.012
Refraction index $n_{\alpha}$
1.541 - 1.5625
Refraction index $n_{\beta}$
1.565
Refraction index $n_{\gamma}$
1.553 - 1.568
Dispersion V
weak to distinct
Pure color
white
Color
green, green blue, yellow, white
Diaphaneity
translucent
Luster
waxy
Links