Montmorillonite [ (Na,Ca)0.3(Al,Mg)2Si4O10(OH)2·nH2O ]

Material properties

Formulas (Na,Ca)0.3(Al,Mg,Fe)2Si4O10(OH)2·nH2O, (Na,Ca)0.3(Al,Mg)2Si4O10(OH)2·nH2O
Abbreviation Mnt
Variant Fe
Classifications Minerals containing OH, Smectite (group), Minerals containing H2O
Luminescence emitters OH, Si-O
IMA Status Grandfathered (pre-IMA), 1847
Search other databases webmineral.com, mindat.org, rruf.info, mineralienatlas.de, Handbook of Mineralogy, American Mineralogist Crystal Structure Database
Crystal symmetry Monoclinic, Point group 2/m, Space group C2/m (#12)
Tags Hydrated , Hydroxide, Hydroxide , Mineral, Aluminosilicate

Composition

Al, O, Mg, Si, H, Na, Ca

Specimens of Montmorillonite

Name Owner Materials Phase purity Image Spectra Techniques
Saz-1 Montmorillonite CSIRO Montmorillonite (99.2%) 99.2 0
SCa-3 Montmorillonite CSIRO Montmorillonite (97.7%), Quartz 97.7 0
Swy-1 Montmorillonite CSIRO Montmorillonite (90.1%), Orthoclase, Quartz 90.1 0
APIH23 Montmorillonite / Calcite CSIRO Calcite, Montmorillonite (85.5%) 85.5 0
Swy-2 Montmorillonite CSIRO Montmorillonite (84.9%), Orthoclase, Quartz 84.9 0
STx-1 Montmorillonite / Cristobalite CSIRO Cristobalite, Montmorillonite (80.3%) 80.3 0
Swa-1 Montmorillonite / Quartz CSIRO Goethite, Montmorillonite, Fe (79.0%), Quartz 79.0 0
SBCa-1 Montmorillonite / Quartz CSIRO Anatase, Kaolinite, Montmorillonite (70.8%), Quartz 70.8 0
M2803 Malachite / Montmorillonite / Goethite CSIRO Goethite, Hematite, Malachite, Montmorillonite (21.4%), Quartz 21.4 0
API-H46-1 Palygorskite / Montmorillonite / Sepiolite CSIRO Montmorillonite (20.2%), Palygorskite, Quartz, Sepiolite 20.2 0
MT8388a Palygorskite / Montmorillonite / Quartz CSIRO Goethite, Montmorillonite (16.4%), Palygorskite, Quartz 16.4 0
PFl-1 Palygorskite / Montmorillonite CSIRO Fluor-elbaite, Goethite, Montmorillonite (14.4%), Palygorskite, Quartz 14.4 0
MES078 Hedenbergite / Montmorillonite CSIRO Hedenbergite, Magnesite, Montmorillonite (14.0%), Pyrite, Quartz 14.0 0
M0891 Goethite / Montmorillonite CSIRO Goethite, Hematite, Microcline, Montmorillonite (12.3%), Quartz 12.3 0
M1646 Goethite / Malachite / Hematite CSIRO Goethite, Hematite, Malachite, Montmorillonite (5.5%), Quartz 5.5 0
M0834 Albite / Augite / Sanidine CSIRO Albite, Ca, Ankerite, Augite, Forsterite, Fe, Ilmenite, Montmorillonite (5.2%), Sanidine 5.2 0
MT8407 Meionite / Prehnite CSIRO Kaolinite, Meionite, Montmorillonite (3.2%), Muscovite-1M, Muscovite-2M1, Prehnite, Pumpellyite-(Mg), Cr, Scapolite 3.2 1 Reflectance
API13 Kaolinite / Halloysite CSIRO Albite, Halloysite, hkl, Illite-Smectite 12.0A, Kaolinite, Montmorillonite (2.8%), Orthoclase, Quartz 2.8 0