Donate now to keep mindat.org alive!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 Mindat
The most common minerals on earthMineral PhotographyThe Elements and their Minerals
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
StatisticsThe ElementsMember ListBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Smectite Group

This page is currently not sponsored. Click here to sponsor this page.
Formula:
A0.3D2-3[T4O10]Z2 · nH2O
Monoclinic clay-like minerals.

Positive identification of minerals in the smectite group may need data from dehydration experiments (thermogravimetric analysis, TGA, or differential thermo-analysis, DTA), and X-ray powder patterns before and after treatment by heating and with organic liquids.

The most common members are montmorillonite, nontronite and saponite. A possible V-dominant member is coded as 'UM1979-21-SiO:AlHNaV'.



Hide all sections | Show all sections

Chemical Properties of Smectite GroupHide

Formula:
A0.3D2-3[T4O10]Z2 · nH2O

Synonyms of Smectite GroupHide

Other Language Names for Smectite GroupHide

Esperanto:Smektitoj
German:Smectit
Simplified Chinese:蒙脱石族
蒙皂石
Spanish:Smectita

Relationship of Smectite Group to other SpeciesHide

Group Members:
Aliettite Ca0.2Mg6((Si,Al)8O20)(OH)4 · 4H2OMon.
Beidellite (Na,Ca0.5)0.3Al2((Si,Al)4O10)(OH)2 · nH2OMon.
Ferrosaponite Ca0.3(Fe2+,Mg,Fe3+)3((Si,Al)4O10)(OH)2 · 4H2O
Hectorite Na0.3(Mg,Li)3(Si4O10)(F,OH)2Mon.
Montmorillonite (Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2OMon. 2/m : B2/m
Nontronite Na0.3Fe2((Si,Al)4O10)(OH)2 · nH2OMon.
Pimelite Ni3Si4O10(OH)2·4H2OHex.
Saliotite (Li,Na)Al3(AlSi3O10)(OH)5Mon.
Saponite Ca0.25(Mg,Fe)3((Si,Al)4O10)(OH)2 · nH2OMon.
Sauconite Na0.3Zn3((Si,Al)4O10)(OH)2 · 4H2OMon.
Stevensite (Ca,Na)xMg3-x(Si4O10)(OH)2Mon.
Swinefordite Li(Al,Li,Mg)4((Si,Al)4O10)2(OH,F)4 · nH2OMon.
Volkonskoite Ca0.3(Cr,Mg,Fe)2((Si,Al)4O10)(OH)2 · 4H2OMon.
Yakhontovite (Ca,Na)0.5(Cu,Fe,Mg)2(Si4O10)(OH)2 · 3H2OMon.
Zincsilite Zn3(Si4O10)(OH)2 · 4H2OMon.

Other InformationHide

Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Smectite Group in petrologyHide

References for Smectite GroupHide

Reference List:
Sort by Year (asc) | by Year (desc) | by Author (A-Z) | by Author (Z-A)
Mering, J. and Oberlin, A. (1967) Electron-optical study of smectites. Clays & Clay Minerals: 15: 3-25.
Schultz, L.G. (1969) Lithium and potassium absorption, dehydroxylation temperature and structural water content of aluminous smectites. Clays and Clay Minerals 17: 115-149.
Harder, H. (1972) The role of magnesium in the formation of smectite minerals. Chemical Geology: 10: 31-39.
Lagaly, G. and Weiss, A. (1975) The layer charge of smectite layer silicates. In S.W. Bale, Editor, Proceedings of International Clay Conference, Mexico p. 157-172. Applied Publishing Ltd., Wilmette, Illinois.
Eslinger, E., Highsmith, P., Albers, D., and deMayo, B. (1979) Role of iron reduction in the conversion of smectite to illite in bentonites in the disturbed belt. Montana: Clays and Clay Minerals: 27: 327-338.
Brigatti, M.F. and Poppi, L. (1981) A mathematical model to distinguish the members of the dioctahedral smectite series. Clay Minerals: 16: 81-89.
Nahon, D., Colin, F., and Tardy, Y. (1982) Formation and distribution of Mg, Fe, Mn- smectites in the first stages of the lateritic weathering of forsterite and tephroite. Clay Minerals: 17: 339-348.
Brigatti, M.F. (1983) Relationships between composition and structure in Fe-rich smectites. Clay Minerals: 18: 177-186.
Talibudeen, O. and Goulding, K.W.T. (1983) Charge heterogeneity in smectites. Clays and Clay Minerals: 31: 37-42.
May, H.M., Kinniburgh, D.G., Helmke, P.A., and Jackson, M.L. (1986) Aqueous dissolution, solubilities and thermodynamic stabilities of common alumino-silicate clay minerals; kaolinite and smectite. Geochimica et Cosmochimica Acta: 50: 1667-1677.
Nadeau, P. and Bain, D. (1986) Composition of some smectites and diagenetic illitic clays and implications for their origin. Clays and Clay Minerals: 34: 455-464.
Decarreau, A., Colin, F., Herbillon, A., Manceau, A., Nahon, D., Paquet, H., Trauth-Badeaud, D., and Trescases, J.J. (1987) Domain segregation in Ni-Fe-Mg-smectites. Clays and Clay Minerals: 35: 1-10.
Iwazaki, T. and Watanabe, T. (1988) Distribution of Ca and Na ions in dioctahedral smectites and interstratified dioctahedral mica/smectites. Clays and Clay Minerals: 36: 73-82.
Madejova, J., Putyera, K., and Čičel, B. (1992) Proportion of central atoms in octahedral layers of smectites calculated from IR spectra. Geologica Carpathica Series Clays: 43: 117-120.
Christidis, G.E. and Dunham, A.C (1997) Compositional variations in smectites: Part II. Alteration of acidic precursors. A case study from Milos Island, Greece. Clay Minerals: 32: 253-270.
Madejova, J., Komadel, P., and Čičel, B. (1994) Infrared study of octahedral site populations in smectites. Clay Minerals: 29: 319-326.
Cuadros, J. and Altaner, S.P. (1998) Compositional and structural features of the octahedral sheet in mixed layer illite-smectite from bentonites. European Journal of Mineralogy: 10: 111-124.
Köster, H.M., Ehrlicher, U., Gilg, H.A., Jordan, R., Murad, E., and Onnich, K. (1999) Mineralogical and chemical characteristics of five nontronites and Fe-rich smectites. Clay Minerals: 34: 579-599.
Manceau, A., Lanson, B., Drits, V.A., Chateigner, D., Gates, W.P., Wu, J., Huo, D., and Stucki, J.W. (2001) Oxidation-reduction mechanism of iron in dioctahedral smectites. I. Crystal chemistry of oxidized reference nontronites. American Mineralogist: 85: 133-152.
Christidis, G.E. and Eberl, D.D. (2003) Determination of layer charge characteristics of smectites. Clays and Clay Minerals: 51: 644-655.
Pironon, J., Pelletier, M., De Donato, P., and Mosser-Ruck, R. (2003) Characterization of smectite and illite by FTIR spectroscopy of interlayer NH4 + cations. Clay Minerals: 38: 201-211.
Sainz-Diaz, C.I., Palin, E.J., Dove, M.T., and Hernandez-Laguna, A. (2003) Monte Carlo simulations of ordering of Al, Fe and Mg cations in the octahedral sheet of smectites and illites. American Mineralogist: 88: 1033-1045.
Sainz-Diaz, C.I., Palin, E.J., Hernandez-Laguna, A., and Dove, M.T. (2003) Octahedral cation ordering of illite and smectite. Theoretical exchange potential determination and Monte Carlo simulation. Physics and Chemistry of Minerals: 30: 382-392.
Gaudin, A., Petit, S., Rose, J., Martin, F., Decarreau, A., Noack, Y., and Borschneck, D. (2004) The accurate crystal chemistry of ferric smectites from the lateritic nickel ore of Murin Murin (Western Australia). II. Spectroscopic (IR and EXAFS) approaches. Clay Minerals: 39: 453-467.
Dainyak, L.G., Drits, V.A., Zviagina, B.B., and Lindgreen, H. (2006) Cation redistribution in the octahedral sheet during diagenesis of illite-smectites from Jurassic and Cambrian oil source rock shales. American Mineralogist: 91: 589-603.
Christidis, G.E. (2006) Genesis and compositional heterogeneity of smectites. Part III: Alteration of basic pyroclastic rocks - A case study from the Troodos Ophiolite Complex, Cyprus. American Mineralogist: 91: 685-701.
Meunier, A. (2006) Why are clay minerals small? Clay Minerals: 41: 551-566.

Internet Links for Smectite GroupHide

Localities for Smectite GroupHide

This 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.

Locality ListShow