Constituent
Name
Kaolinite
Class
silicate mineral
Compound type
phyllosilicate
Relevance
impurity
Arrangement
coated core
Mass fraction
0.00013 $\pm$ 0.0001
Abundance comments
Mass fraction uncertain (0.013 for < 2µm size - Vogt 2002)
Formula
$Al_2.(Si_2O_5)(OH)_4$
Chemical formula
Al2Si2O5(OH)4
Elemental formula
Al2 O9 H4 Si2
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$Si$ Silicon element 2 constituent element main
$Al$ Aluminium element 2 constituent element main
$O$ Oxygen element 9 constituent element main
$H$ Hydrogen element 4 constituent element main
Chemical functions
  Function Number
$\bullet (OH)^-$ 4
Chemical bonds
  Bond Number
$H-O^-$ 1
Oxides
Formula $Al_{2}O_{3}$ $H_{2}O$ $SiO_{2}$
Mass fraction (%) 39.5 13.96 46.55

Strunz

Class
silicates (09)
Division
phyllosilicate (09.E)
Family
Phyllosilicates with kaolinite layers (09.ED)
Code
09.ED.05

Dana

Major class
silicates (VIII)
Class
phyllosilicate sheets of six-membered rings (71)
Type
with 1:1 layers (71.01)
Group
Kaolinite group (71.01.01)
Code
71.01.01.02
Phase type
crystalline
Crystal system
triclinic
Crystal class
pedial
Crystal class symbol
1 (C1)
Crystal spacegroup
P1
Molar mass
258.16 $g/mol$
Density
2.6 $g/cm^3$
Refringence type
biaxial
Refringence sign
negatif
Birefringence
0.007
Refraction index $n_{\alpha}$
1.553 - 1.563
Refraction index $n_{\beta}$
1.559 - 1.569
Refraction index $n_{\gamma}$
1.560 - 1.570
Dispersion V
r > v weak
Color
white, brownish white, grayish white, yellowish white, grayish green
Diaphaneity
transparent to translucent
Luster
earthy