Help mindat.org|Log In|Register|
Home PageMindat NewsThe Mindat ManualHistory of MindatCopyright StatusManagement TeamContact UsAdvertise on Mindat
Donate to MindatSponsor a PageSponsored PagesTop Available PagesMindat AdvertisersAdvertise on MindatThe Mindat Store
Minerals by PropertiesMinerals by ChemistryRandom MineralSearch by minIDLocalities Near MeSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportAdd Glossary Item
StatisticsMember ListBooks & MagazinesMineral Shows & EventsThe Mindat DirectoryHow to Link to MindatDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Kaolinite

This page is currently not sponsored. Click here to sponsor this page.
Formula:
Al2(Si2O5)(OH)4
System:
Triclinic
Colour:
White to cream and ...
Hardness:
2 - 2½
Name:
Named in 1637 by Song Yingxing for the ancient Chinese type locality "Kaoling (Gaoling)", meaning high ridge.
Mineral used in pre-historic times. Presumably the most important mineral in clay used in pre-historic pottery. http://www.mindat.org/photo-620484.html Sumerian symbol for clay. חלבנהπη in Hebrew. λός in Greek. Lutum in Latin. Kaolinite, by name, was known since the Yuan (Mongol) dynasty in the thirteenth century as "Kaolin earth" and was first properly described by Song Yingxing in 1637 in his book Tian Gong Kai Wu (translated: "Introduction to Heaven's Handicrafts" or "The Exploitation of the Works of Nature"). It's usefullness was introduced to the West by a French priest in 1712 (de Fourestier, 2005).

Found largely in masses - clay beds - usually with a bright white color, also pale yellow to light brown color due to staining or mixture, rarely blue to blue gray.

See also the chemically identical halloysite-7Å.

Classification of Kaolinite

Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
Explanation of status:
Officially "re-described" by Keller et al. (1980).
9.ED.05

9 : SILICATES (Germanates)
E : Phyllosilicates
D : Phyllosilicates with kaolinite layers composed of tetrahedral and octahedral nets
Dana 7th ed.:
71.1.1.2
15.8

15 : Silicates of Aluminum
mindat.org URL:
http://www.mindat.org/min-2156.html
Please feel free to link to this page.

First Recorded Occurrence of Kaolinite

Year of Discovery:
Anci

Occurrences of Kaolinite

Geological Setting:
A primary constiuent of clay beds formed by the decomposition of feldspar-bearing rocks.

Physical Properties of Kaolinite

Waxy, Pearly, Dull, Earthy
Diaphaneity (Transparency):
Translucent, Opaque
Colour:
White to cream and pale-yellow, also often stained various hues, tans and browns being common.
Streak:
White, or paler than the sample.
Hardness (Mohs):
2 - 2½
Hardness Data:
Measured
Tenacity:
Sectile
Cleavage:
Perfect
on {001}.
Fracture:
Irregular/Uneven, Conchoidal, Sub-Conchoidal, Micaceous
Density:
2.63 g/cm3 (Calculated)

Crystallography of Kaolinite

Crystal System:
Triclinic
Class (H-M):
1 - Pedial
Space Group:
P1
Cell Parameters:
a = 5.13Å, b = 8.89Å, c = 7.25Å
α = 90°, β = 104.5°, γ = 89.8°
Ratio:
a:b:c = 0.577 : 1 : 0.816
Z:
1
Morphology:
Visible crystals extremely rare, typically 2-5 nanometer range, but may be up to 1.5 mm across. Platy, pseudohexagonal. Fibers and spheres have been observed using SEM imaging.
X-Ray Powder Diffraction Data:
d-spacingIntensity
7.17(100)
4.37(60)
4.19(45)
3.58(80)
1.62(70)
1.59(60)
1.59(90)
Comments:
Data for For kaolinite-1A: Several polytypes known: -1Md, -2M^1 ("dickite"), -2M^2 ("nacrite"). Each has a slightly different powder pattern.

Optical Data of Kaolinite

Type:
Biaxial (-)
RI values:
nα = 1.553 - 1.563 nβ = 1.559 - 1.569 nγ = 1.560 - 1.570
2V:
Measured: 24° to 50°, Calculated: 44°
Birefringence:
0.017
Max Birefringence:
δ = 0.007
Image shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:
Low
Dispersion:
none
Pleochroism:
Non-pleochroic

Chemical Properties of Kaolinite

Formula:
Al2(Si2O5)(OH)4
Essential elements:
All elements listed in formula:
Common Impurities:
Fe,Mg,Na,K,Ti,Ca,H2O

Relationship of Kaolinite to other Species

Other Members of Group:
AmesiteMg2Al(AlSiO5)(OH)4
AntigoriteMg3(Si2O5)(OH)4
Baumite(Mg,Al,Mn,Zn,Fe)3(Si,Al)2O5(OH)4
Berthierine(Fe2+,Fe3+,Al)3(Si,Al)2O5(OH)4
Brindleyite(Ni,Al)3(Si,Al)2O5(OH)4
Caryopilite(Mn,Mg)3(Si2O5)(OH)4
ChrysotileMg3(Si2O5)(OH)4
Clinochrysotile
CronstedtiteFe22+Fe3+((Si,Fe3+)2O5)(OH)4
DickiteAl2(Si2O5)(OH)4
Fraipontite(Zn,Al)3((Si,Al)2O5)(OH)4
GreenaliteFe2-3(Si2O5)(OH)4
HalloysiteAl2(Si2O5)(OH)4
KellyiteMn22+Al(AlSiO5)(OH)4
LizarditeMg3(Si2O5)(OH)4
ManandoniteLi2Al4(Si2AlB)O10(OH)8
NacriteAl2(Si2O5)(OH)4
Népouite(Ni,Mg)3(Si2O5)(OH)4
Odinite(Fe,Mg,Al,Fe,Ti,Mn)2.4((Si,Al)2O5)(OH)4
Orthochrysotile
Parachrysotile
PecoraiteNi3(Si2O5)(OH)4
Webskyite
9.ED.05DickiteAl2(Si2O5)(OH)4
9.ED.05NacriteAl2(Si2O5)(OH)4
9.ED.05Odinite(Fe,Mg,Al,Fe,Ti,Mn)2.4((Si,Al)2O5)(OH)4
9.ED.10HalloysiteAl2(Si2O5)(OH)4
9.ED.10HisingeriteFe23+(Si2O5)(OH)4 · 2H2O
9.ED.10Halloysite-7ÅAl2(Si2O5)(OH)4
9.ED.15AmesiteMg2Al(AlSiO5)(OH)4
9.ED.15AntigoriteMg3(Si2O5)(OH)4
9.ED.15Berthierine(Fe2+,Fe3+,Al)3(Si,Al)2O5(OH)4
9.ED.15Brindleyite(Ni,Al)3(Si,Al)2O5(OH)4
9.ED.15Caryopilite(Mn,Mg)3(Si2O5)(OH)4
9.ED.15ChrysotileMg3(Si2O5)(OH)4
9.ED.15CronstedtiteFe22+Fe3+((Si,Fe3+)2O5)(OH)4
9.ED.15Fraipontite(Zn,Al)3((Si,Al)2O5)(OH)4
9.ED.15GreenaliteFe2-3(Si2O5)(OH)4
9.ED.15KellyiteMn22+Al(AlSiO5)(OH)4
9.ED.15LizarditeMg3(Si2O5)(OH)4
9.ED.15ManandoniteLi2Al4(Si2AlB)O10(OH)8
9.ED.15Népouite(Ni,Mg)3(Si2O5)(OH)4
9.ED.15PecoraiteNi3(Si2O5)(OH)4
9.ED.15GuidottiiteMn2Fe3+(Fe3+SiO5)(OH)4
9.ED.20Allophane(Al2O3)(SiO2)1.3-2 · 2.5-3H2O
9.ED.20ChrysocollaCu2-xAlx(H2-xSi2O5)(OH)4 · nH2O (x < 1)
9.ED.20ImogoliteAl2SiO3(OH)4
9.ED.20Neotocite(Mn,Fe,Mg)SiO3 · H2O
9.ED.25BismutoferriteFe23+Bi(SiO4)2(OH)
9.ED.25ChapmaniteFe23+Sb3+(Si2O5)O3(OH)
15.1AndalusiteAl2(SiO4)O
15.2KyaniteAl2(SiO4)O
15.3SillimaniteAl2(SiO4)O
15.4MulliteAl4+2xSi2-2xO10-x
15.5PyrophylliteAl2(Si4O10)(OH)2
15.6DickiteAl2(Si2O5)(OH)4
15.7NacriteAl2(Si2O5)(OH)4
15.9Metahalloysite
15.10HalloysiteAl2(Si2O5)(OH)4
15.11Allophane(Al2O3)(SiO2)1.3-2 · 2.5-3H2O
71.1.1.1DickiteAl2(Si2O5)(OH)4
71.1.1.3NacriteAl2(Si2O5)(OH)4
71.1.1.4HalloysiteAl2(Si2O5)(OH)4

Other Names for Kaolinite

Name in Other Languages:
Basque:Kaolinita
Catalan:Caolinita
Cornish:Pri gwynn
Czech:Kaolinit
Estonian:Kaoliniit
Finnish:Kaoliini
French:Kaolinite
Hungarian:Kaolinit
Italian:Caolinite
Norwegian (Bokmål):Kaolinitt
Polish:Kaolinit
Serbian (Cyrillic Script):Каолинит
Simplified Chinese:高岭石
Slovak:Kaolinit
Swedish:Kaolinit
Traditional Chinese:高嶺石
Vietnamese:Cao lanh

Other Information

Not fluorescent in UV.
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Industrial Uses:
Numerous: fillers and coatings in/on papers, for making china and various other earthenware items, an absorbant in dye tracers, a pore-forming enhancer for dye uptake in inks, as an absobant for spills, as a stain preventing coating on lithographic plate

References for Kaolinite

Reference List:
Ross, Clarence Samuel & Paul F. Kerr (1930), The kaolin minerals. USGS Professional Paper 165-E: 151-176.

Brindley, G.W. and Nakahira, M. (1959) The kaolinite-mullite reaction series: I, Survey of outstanding problems. II, Metakaolin. III, The high-temperature phases. Journal of the American Ceramic Society: 42: 311-324.

Conti L., Traversa G. (1968) - Caolinite ottenuta per trasformazione idrotermale della biotite. Periodico di mineralogia –Roma, pp. 605-624.

Bailey, S.W. & R.B. Langston (1969), Anauxite and kaolinite structure identical: Clays and Clay Minerals: 17: 241-243.

Langston, R.B. & J.A. Pask (1969), The nature of anauxite: Clays and Clay Minerals: 16: 425-436.

Leonard, A.J. (1977) Structural analysis of the transition phases in the kaolinite-mullite thermal sequence ournal of the American Ceramic Society: 60: 37-43.

Keller, W.D., Hsia Cheng, Johns, W.D., and Chi-Sheng Meng (1980): Kaolin from the original Kauling (Gaoling) Mine locality, Kiangsi Province, China. Clays and Clay Minerals 28(2), 97-104.

May, H.M., D.G. Kinniburgh, P.A. Helmke, and M.L. Jackson (1986), Aqueous dissolution, solubilities and thermodynamic stabilities of common alumino-siolicate cla minerals; kaolinite and smectite. Geochimica et Cosmochimica Acta 50, 1667-1677.

Bish, D. L., von Dreele, R. B. (1989): Rietveld refinement of non-hydrogen atomic positions in kaolinite. Clays and Clay Minerals 37, 289-296.

Srikrisna, K., Thomas, G., Martinez, R., Corral, M.P., de Aza, S., and Moya, J.S. (1990) Kaolinite-mullite reaction series: a TEM study. Journal of Materials Science: 25: 607-612.

Bish, D. L. (1993): Rietveld refinement of the kaolinite structure at 1.5 K. Clays and Clay Minerals 41, 738-744.

Gaines, Richard V., H. Catherine, W. Skinner, Eugene E. Foord, Brian Mason, Abraham Rosenzweig (1997), Dana's New Mineralogy : The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana: 1407.

Farmer, V. C. (1998): Differing effects of particle size and shape in the infrared and Raman spectra of kaolinite. Clay Minerals 33, 601-604.

Lee, S., Kim, Y.J., and Moon, H.S. (1999) Phase transformation sequence from kaolinite to mullite investigated by an energy-filtering transmission electron microscope. Journal of the American Ceramic Society: 82: 2841-2848.

Farmer, V.C. (2000) Transverse and longitudinal crystal modes associated with OH stretching vibrations in single crystals of kaolinite and dickite. Spectrochimica Acta: A56: 927-930.

Frost, R.L., Fredericks, P.M., Kloprogge, J.T., and Hope, G.A. (2001) Raman spectroscopy of kaolinites using different excitation wavelengths. Journal of Raman Spectroscopy: 32: 657-663.

Balan E, Delattre S, Guillaumet M, Salje E K H (2010): Low-temperature infrared spectroscopic study of OH-stretching modes in kaolinite and dickite. American Mineralogist 95, 1257-1266.

Balan, E., Calas, G. and Bish, D. L. (2014): Kaolin-group minerals: From hydrogen-bonded layers to environmental recorders. Elements 10, 183-188.

Internet Links for Kaolinite

Localities for Kaolinite

map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2015, except where stated. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: April 19, 2015 04:13:46 Page generated: April 12, 2015 02:14:56