Constituent
Name
Kaolinite
IMA name
Kaolinite
Class
silicate mineral
Compound type
phyllosilicate
Comments
from Vogt et al. (2002)
Relevance
main - major
Arrangement
single phase
Mass fraction
1.0 ± 0.001
Formula
Al2.(Si2O5)(OH)4
Chemical formula
Al2Si2O5(OH)4
Elemental formula
Al2 Si2 O9 H4
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
Al Aluminium element 2 constituent element main
Si Silicon element 2 constituent element main
O Oxygen element 9 constituent element main
H Hydrogen element 4 constituent element main
Composition comments
Common impurities: Fe, Mg, Na, K, Ti, Ca, H2O
Chemical functions
  Function Number
(OH) 4
Chemical bonds
  Bond Number
OH 1
Oxides
Formula Al2O3 SiO2 H2O
Mass fraction (%) 39.5 46.55 13.96

Strunz

Class
silicates (09)
Division
phyllosilicate (09.E)
Family
with kaolinite layers composed of tetrahedral and octahedral nets (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
Texture
unknown
Molar mass
258.16 g/mol
Density
2.6 g/cm3
Refringence type
biaxial
Refringence sign
negative
Birefringence
0.007
Refraction index nα
1.553 - 1.563
Refraction index nβ
1.559 - 1.569
Refraction index nγ
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