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Montmorillonite

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Formula:
(Na,Ca)
 
0.33
(Al,Mg)
 
2
(Si
 
4
O
 
10
)(OH)
 
2
· nH
 
2
O
System:MonoclinicColour:White, buff, yellow, ...
Hardness:1 - 2
Member of:Smectite Group
Name:For the type locality at Montmorillon, Vienne, Poitou-Charentes, France.
Isostructural with:Smectite Group

Classification of Montmorillonite

IMA status:Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
Strunz 8th edition ID:8/H.18-20
Nickel-Strunz 10th (pending) edition ID:9.EC.40

9 : SILICATES (Germanates)
E : Phyllosilicates
C : Phyllosilicates with mica sheets, composed of tetrahedral and octahedral nets
Dana 8th edition ID:71.3.1a.2

71 : PHYLLOSILICATES Sheets of Six-Membered Rings
3 : Sheets of 6-membered rings with 2:1 clays
Hey's CIM Ref.:16.7.9

16 : Silicates Containing Aluminum and other Metals
7 : Aluminosilicates of Mg
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Type Occurrence of Montmorillonite

Type Locality:Montmorillon, Vienne, Poitou-Charentes, France
General Appearance of Type Material:Compact earthy massive mineral.
Year of Discovery:1847

Occurrences of Montmorillonite

Geological Setting:Alteration product of volcanic tuffs and ash. Late-hydrothermal formation in various rocks.

Physical Properties of Montmorillonite

Lustre:Dull, Earthy
Diaphaneity (Transparency):Translucent
Comment:Low luster because of fine-grained nature of the mineral
Colour:White, buff, yellow, green, rarely pale pink to red
Comment:Pink to red coloration is due to high valance Mn
Streak:white
Hardness (Mohs):1 - 2
Comment:Soft because of fine-grained occurrence
Cleavage:Perfect
on {001}
Fracture:Irregular/Uneven
Density (measured):2 - 3 g/cm3

Crystallography of Montmorillonite

Crystal System:Monoclinic
Class (H-M):2/m - Prismatic
Space Group:B2/m {B1 1 2/m} {C2/m} {C1 2/m 1}
Cell Parameters:a = 5.17Å, b = 8.94Å, c = 9.95Å
β = 99.54°
Ratio:a:b:c = 0.578 : 1 : 1.113
Unit Cell Volume:V 453.53 ų (Calculated from Unit Cell)
Z:1
Morphology:Scaly crystals, clayey, compact, massive
X-Ray Powder Diffraction:
d-spacingIntensity
15.0 (100)
5.01 (60)
4.50 (80)
3.77 (20)
3.02 (60)
1.70 (30)
1.50 (50)
1.49 (50)
Comments:Basal spacings sensitive to interlayer hydration. Dehydrated montmorillonite may have a 13.6 Angstrom spacing.

Optical Data of Montmorillonite

Type:Biaxial (-)
RI values: nα = 1.485 - 1.535 nβ = 1.504 - 1.550 nγ = 1.505 - 1.550
2V:Measured: 5° to 30°
Birefringence:0.02
Maximum Birefringence:δ = 0.020

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:Low
Dispersion:none
Pleochroism:Visible
Comments:X= colorless to pale brown, yellow green
Y= dark brown to yellow-green, olive-green, pale yellow
Z= brown to olive-green, pale yellow
Comments:Usually not pleochroic; pleochroism dependent on chemical substitution

Chemical Properties of Montmorillonite

Formula:
(Na,Ca)
 
0.33
(Al,Mg)
 
2
(Si
 
4
O
 
10
)(OH)
 
2
· nH
 
2
O
Simplified for copy/paste:(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2·nH2O
Essential elements:Al, H, Na, O, Si
All elements listed in formula:Al, Ca, H, Mg, Na, O, Si
Common Impurities:Fe,K

Relationship of Montmorillonite to other Species

Series:Forms a series with Beidellite (see here)
Member of:Smectite Group
Other Members of Group:

- +
Aliettite
Ca
 
0.2
Mg
 
6
((Si,Al)
 
8
O
 
20
)(OH)
 
4
· 4H
 
2
O
Beidellite
(Na,Ca
 
0.5
)
 
0.3
Al
 
2
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· nH
 
2
O
Ferrosaponite
Ca
 
0.3
(Fe
2+
 
,Mg,Fe
3+
 
)
 
3
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· 4H
 
2
O
Hectorite
Na
 
0.3
(Mg,Li)
 
3
(Si
 
4
O
 
10
)(F,OH)
 
2
Nontronite
Na
 
0.3
Fe
 
2
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· nH
 
2
O
Pimelite
Ni
 
3
Si
 
4
O
 
10
(OH)
 
2
·4H
 
2
O
Saliotite
(Li,Na)Al
 
3
(AlSi
 
3
O
 
10
)(OH)
 
5
Saponite
Ca
 
0.25
(Mg,Fe)
 
3
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· nH
 
2
O
Sauconite
Na
 
0.3
Zn
 
3
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· 4H
 
2
O
Stevensite
(Ca,Na)
 
x
Mg
 
3-x
(Si
 
4
O
 
10
)(OH)
 
2
Swinefordite
Li(Al,Li,Mg)
 
4
((Si,Al)
 
4
O
 
10
)
 
2
(OH,F)
 
4
· nH
 
2
O
Volkonskoite
Ca
 
0.3
(Cr,Mg,Fe)
 
2
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· 4H
 
2
O
Yakhontovite
(Ca,Na)
 
0.5
(Cu,Fe,Mg)
 
2
(Si
 
4
O
 
10
)(OH)
 
2
· 3H
 
2
O
Zincsilite
Zn
 
3
(Si
 
4
O
 
10
)(OH)
 
2
· 4H
 
2
O
Structurally related to group(s):
Montmorillonite-Vermiculite Group
Related Minerals - Nickel-Strunz Grouping):

- +
9.EC.05Minnesotaite
(Fe,Mg)
 
3
(Si
 
4
O
 
10
)(OH)
 
2
9.EC.05Talc
Mg
 
3
(Si
 
4
O
 
10
)(OH)
 
2
9.EC.05Willemseite
(Ni,Mg)
 
3
(Si
 
4
O
 
10
)(OH)
 
2
9.EC.10Ferripyrophyllite
Fe
3+
2
(Si
 
4
O
 
10
)(OH)
 
2
9.EC.10Pyrophyllite
Al
 
2
(Si
 
4
O
 
10
)(OH)
 
2
9.EC.15Boromuscovite
KAl
 
2
(BSi
 
3
O
 
10
)(OH)
 
2
9.EC.15Celadonite
K(Mg,Fe
2+
 
)Fe
3+
 
(Si
 
4
O
 
10
)(OH)
 
2
9.EC.15Chernykhite
(Ba,Na)(V
3+
 
,Al,Mg)
 
2
((Si,Al)
 
4
O
 
10
)(OH)
 
2
9.EC.15Montdorite
(K,Na)
 
2
(Fe
2+
 
,Mn
2+
 
,Mg)
 
5
(Si
 
4
O
 
10
)
 
2
(OH,F)
 
4
9.EC.15Muscovite
KAl
 
2
(AlSi
 
3
O
 
10
)(OH)
 
2
9.EC.15Nanpingite
CsAl
 
2
(AlSi
 
3
O
 
10
)(OH,F)
 
2
9.EC.15Paragonite
NaAl
 
2
(AlSi
 
3
O
 
10
)(OH)
 
2
9.EC.15Roscoelite
K(V
3+
 
,Al)
 
2
(AlSi
 
3
O
 
10
)(OH)
 
2
9.EC.15Tobelite
(NH
 
4
,K)Al
 
2
(AlSi
 
3
O
 
10
)(OH)
 
2
9.EC.15Aluminoceladonite
K(Mg,Fe
2+
 
)Al(Si
 
4
O
 
10
)(OH)
 
2
9.EC.15Chromphyllite
K(Cr,Al)
 
2
(AlSi
 
3
O
 
10
)(OH,F)
 
2
9.EC.15Ferro-aluminoceladonite
K(Fe
2+
 
,Mg)(Al,Fe
3+
 
)(Si
 
4
O
 
10
)(OH)
 
2
9.EC.15Ferroceladonite
K(Fe
2+
 
,Mg)(Fe
3+
 
,Al)(Si
 
4
O
 
10
)(OH)
 
2
9.EC.15Chromceladonite
K(Mg,Fe
2+
 
)(Cr,Al)(Si
 
4
O
 
10
)(OH)
 
2
9.EC.15Tainiolite
KLiMg
 
2
(Si
 
4
O
 
10
)F
 
2
9.EC.15Ganterite
(Ba,Na,K)(Al,Mg)
 
2
(AlSi
 
3
O
 
10
)(OH)
 
2
9.EC.20Annite
KFe
2+
3
(AlSi
 
3
O
 
10
)(OH)
 
2
9.EC.20Ephesite
LiNaAl
 
2
(Al
 
2
Si
 
2
O
 
10
)(OH)
 
2
9.EC.20Hendricksite
K(Zn,Mg,Mn
2+
 
)
 
3
(AlSi
 
3
O
 
10
)(OH)
 
2
9.EC.20Masutomilite
(K,Rb)(Li,Mn
3+
 
,Al)
 
3
(AlSi
 
3
O
 
10
)(F,OH)
 
2
9.EC.20Norrishite
KLiMn
3+
2
(Si
 
4
O
 
10
)O
 
2
9.EC.20Phlogopite
KMg
 
3
(AlSi
 
3
O
 
10
)(OH,F)
 
2
9.EC.20Polylithionite
KLi
 
2
Al(Si
 
4
O
 
10
)(F,OH)
 
2
9.EC.20Preiswerkite
NaMg
 
2
Al(Al
 
2
Si
 
2
O
 
10
)(OH)
 
2
9.EC.20Siderophyllite
KFe
2+
2
Al(Al
 
2
Si
 
2
O
 
10
)(OH)
 
2
9.EC.20Tetraferriphlogopite
KMg
 
3
(Fe
3+
 
Si
 
3
O
 
10
)(OH,F)
 
2
9.EC.20Fluorotetraferriphlogopite
KMg
 
3
(Fe
3+
 
Si
 
3
O
 
10
)F
 
2
9.EC.20Wonesite
(Na,K)(Mg,Fe,Al)
 
6
((Al,Si)
 
4
O
 
10
)
 
2
(OH,F)
 
4
9.EC.20Eastonite
KMg
 
2
Al(Al
 
2
Si
 
2
O
 
10
)(OH)
 
2
9.EC.20Tetraferriannite
KFe
2+
3
((Fe
3+
 
,Al)Si
 
3
O
 
10
)(OH)
 
2
9.EC.20Trilithionite
K(Li,Al)
 
3
(AlSi
 
3
O
 
10
)(F,OH)
 
2
9.EC.20Fluorannite
KFe
2+
3
(AlSi
 
3
O
 
10
)(F,OH)
 
2
9.EC.20Shirokshinite
KNaMg
 
2
(Si
 
4
O
 
10
)F
 
2
9.EC.20Shirozulite
K(Mn
2+
 
,Mg)
 
3
(AlSi
 
3
O
 
10
)(OH)
 
2
9.EC.20Sokolovaite
CsLi
 
2
Al(Si
 
4
O
 
10
)F
 
2
9.EC.20Aspidolite
NaMg
 
3
(AlSi
 
3
O
 
10
)(OH)
 
2
9.EC.20Fluorophlogopite
KMg
 
3
(AlSi
 
3
O
 
10
)(F,OH)
 
2
9.EC.20UM2004-49-SiO:AlCsFHKLi
(Cs,K)(Al,Li)
 
2.6
((Si,Al)
 
4
O
 
10
)(F,OH)
 
2
9.EC.20Suhailite
(NH
 
4
)Fe
2+
3
(AlSi
 
3
O
 
10
)(OH)
 
2
9.EC.20Yangzhumingite
KMg
 
2.5
(Si
 
4
O
 
10
)F
 
2
9.EC.20Orlovite
KLi
 
2
Ti(Si
 
4
O
 
10
)OF
9.EC.20Oxyphlogopite
K(Mg,Ti,Fe)
 
3
[(Si,Al)
 
4
O
 
10
](O,F)
 
2
9.EC.25Brammallite
(Na,H
 
3
O)(Al,Mg,Fe)
 
2
((Si,Al)
 
4
O
 
10
)(OH)
 
2
9.EC.30Margarite
CaAl
 
2
(Al
 
2
Si
 
2
O
 
10
)(OH)
 
2
9.EC.35Anandite
(Ba,K)(Fe
2+
 
,Mg)
 
3
((Si,Al,Fe)
 
4
O
 
10
)(S,OH)
 
2
9.EC.35Bityite
LiCaAl
 
2
(AlBeSi
 
2
O
 
10
)(OH)
 
2
9.EC.35Clintonite
Ca(Mg,Al)
 
3
(Al
 
3
SiO
 
10
)(OH)
 
2
9.EC.35Kinoshitalite
(Ba,K)(Mg,Mn
2+
 
,Al)
 
3
(Al
 
2
Si
 
2
O
 
10
)(OH)
 
2
9.EC.35Ferrokinoshitalite
(Ba,K)(Fe
2+
 
,Mg)
 
3
(Al
 
2
Si
 
2
O
 
10
)(OH,F)
 
2
9.EC.35Oxykinoshitalite
(Ba,K)(Mg,Ti,Fe
3+
 
,Fe
2+
 
)
 
3
((Si,Al)
 
4
O
 
10
)(O,OH,F)
 
2
9.EC.35Fluorokinoshitalite
BaMg
 
3
(Al
 
2
Si
 
2
O
 
10
)F
 
2
9.EC.40Beidellite
(Na,Ca
 
0.5
)
 
0.3
Al
 
2
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· nH
 
2
O
9.EC.40Kurumsakite
(Zn,Ni,Cu)
 
8
Al
 
8
V
5+
2
Si
 
5
O
 
35
· 27H
 
2
O (?)
9.EC.40Nontronite
Na
 
0.3
Fe
 
2
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· nH
 
2
O
9.EC.40Volkonskoite
Ca
 
0.3
(Cr,Mg,Fe)
 
2
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· 4H
 
2
O
9.EC.40Yakhontovite
(Ca,Na)
 
0.5
(Cu,Fe,Mg)
 
2
(Si
 
4
O
 
10
)(OH)
 
2
· 3H
 
2
O
9.EC.45Hectorite
Na
 
0.3
(Mg,Li)
 
3
(Si
 
4
O
 
10
)(F,OH)
 
2
9.EC.45Saponite
Ca
 
0.25
(Mg,Fe)
 
3
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· nH
 
2
O
9.EC.45Sauconite
Na
 
0.3
Zn
 
3
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· 4H
 
2
O
9.EC.45Spadaite
MgSiO
 
2
(OH)
 
2
· H
 
2
O (?)
9.EC.45Stevensite
(Ca,Na)
 
x
Mg
 
3-x
(Si
 
4
O
 
10
)(OH)
 
2
9.EC.45Swinefordite
Li(Al,Li,Mg)
 
4
((Si,Al)
 
4
O
 
10
)
 
2
(OH,F)
 
4
· nH
 
2
O
9.EC.45Zincsilite
Zn
 
3
(Si
 
4
O
 
10
)(OH)
 
2
· 4H
 
2
O
9.EC.45Ferrosaponite
Ca
 
0.3
(Fe
2+
 
,Mg,Fe
3+
 
)
 
3
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· 4H
 
2
O
9.EC.50Vermiculite
(Mg,Fe,Al)
 
3
((Al,Si)
 
4
O
 
10
)(OH)
 
2
· 4H
 
2
O
9.EC.55Baileychlore
(Zn,Fe,Al,Mg)
 
6
((Si,Al)
 
4
O
 
10
)(OH)
 
8
9.EC.55Chamosite
(Fe
2+
 
,Mg)
 
5
Al(AlSi
 
3
O
 
10
)(OH)
 
8
9.EC.55Clinochlore
(Mg,Fe
2+
 
)
 
5
Al(AlSi
 
3
O
 
10
)(OH)
 
8
9.EC.55Cookeite
(Al
 
2
Li)Al
 
2
(AlSi
 
3
O
 
10
)(OH)
 
8
9.EC.55Franklinfurnaceite
Ca
 
2
Fe
3+
 
Mn
2+
3
Mn
3+
 
(Zn
 
2
Si
 
2
O
 
10
)(OH)
 
8
9.EC.55Gonyerite
(Mn
2+
 
,Mg)
 
5
Fe
3+
 
(Fe
3+
 
Si
 
3
O
 
10
)(OH)
 
8
9.EC.55Nimite
(Ni,Mg,Al)
 
6
((Si,Al)
 
4
O
 
10
)(OH)
 
8
9.EC.55Orthochamosite
(Fe
2+
 
,Mg,Fe
3+
 
)
 
5
Al(AlSi
 
3
O
 
10
)(OH,O)
 
8
9.EC.55Pennantite
Mn
2+
5
Al(AlSi
 
3
O
 
10
)(OH)
 
8
9.EC.55Sudoite
(Mg,Fe
2+
 
)
 
2
Al
 
3
(AlSi
 
3
O
 
10
)(OH)
 
8
9.EC.55Donbassite
Al
 
4.33
(AlSi
 
3
O
 
10
)(OH)
 
8
9.EC.55Glagolevite
Na(Mg,Al)
 
6
(AlSi
 
3
O
 
10
)(OH,O)
 
8
9.EC.55Borocookeite
Li
 
1+3x
Al
 
4-x
(BSi
 
3
O
 
10
)(OH)
 
8
9.EC.60Aliettite
Ca
 
0.2
Mg
 
6
((Si,Al)
 
8
O
 
20
)(OH)
 
4
· 4H
 
2
O
9.EC.60Corrensite
(Mg,Fe)
 
9
((Si,Al)
 
8
O
 
20
)(OH)
 
10
· nH
 
2
O
9.EC.60Dozyite
Mg
 
7
Al
 
2
(Al
 
2
Si
 
4
O
 
15
)(OH)
 
12
9.EC.60Hydrobiotite
K(Mg,Fe
2+
 
)
 
6
((Si,Al)
 
8
O
 
20
)(OH)
 
4
· nH
 
2
O
9.EC.60Karpinskite
(Ni,Mg)
 
2
Si
 
2
O
 
5
(OH)
 
2
(?)
9.EC.60Kulkeite
Mg
 
8
Al(AlSi
 
7
O
 
20
)(OH)
 
10
9.EC.60Lunijianlaite
Li
 
0.7
Al
 
6.2
(AlSi
 
7
O
 
20
)(OH,O)
 
10
9.EC.60Rectorite
(Na,Ca)Al
 
4
((Si,Al)
 
8
O
 
20
)(OH)
 
4
· 2H
 
2
O
9.EC.60Saliotite
(Li,Na)Al
 
3
(AlSi
 
3
O
 
10
)(OH)
 
5
9.EC.60Tosudite
Na
 
0.5
(Al,Mg)
 
6
((Si,Al)
 
8
O
 
18
)(OH)
 
12
· 5H
 
2
O
9.EC.60Brinrobertsite
Na
 
0.3
Al
 
4
(Si
 
4
O
 
10
)
 
2
(OH)
 
4
· 3.5 H
 
2
O
9.EC.65Macaulayite
(Fe,Al)
 
24
Si
 
4
O
 
43
(OH)
 
2
9.EC.70Burckhardtite
Pb
 
2
(Fe
3+
 
,Mn
3+
 
)Te
4+
 
(AlSi
 
3
O
 
10
)O
 
2
(OH)
 
2
· H
 
2
O
9.EC.75Ferrisurite
(Pb,Ca)
 
2.4
Fe
3+
2
(Si
 
4
O
 
10
)(CO
 
3
)
 
1.7
(OH)
 
3
· nH
 
2
O
9.EC.75Surite
(Pb,Ca)
 
3
(Al,Fe
2+
 
,Mg)
 
2
((Si,Al)
 
4
O
 
10
)(CO
 
3
)
 
2
(OH)
 
2
9.EC.75Niksergievite
(Ba,Ca)
 
2
Al
 
3
(AlSi
 
3
O
 
10
)(CO
 
3
)(OH)
 
6
· nH
 
2
O
9.EC.80Kegelite
Pb
 
8
Al
 
4
(Si
 
8
O
 
20
)(SO
 
4
)
 
2
(CO
 
3
)
 
4
(OH)
 
8
Related Minerals - Hey's Index Grouping:

- +
16.7.1Pyrope
Mg
 
3
Al
 
2
(SiO
 
4
)
 
3
16.7.2Sapphirine
(Mg,Fe)
 
4-x
Al
 
4+x
[Al
 
4+x
Si
 
2-x
O
 
18
]O
 
2
16.7.3Sapphirine-1A
(Mg,Al,Fe
2+
 
)
 
8
[(Al,Si,Fe
3+
 
)
 
6
O
 
18
]O
 
2
16.7.4Magnesiochloritoid
MgAl
 
2
(SiO
 
4
)O(OH)
 
2
16.7.5Kulkeite
Mg
 
8
Al(AlSi
 
7
O
 
20
)(OH)
 
10
16.7.6Palygorskite
(Mg,Al)
 
5
(Si,Al)
 
8
O
 
20
(OH)
 
2
· 8H
 
2
O
16.7.7Saponite
Ca
 
0.25
(Mg,Fe)
 
3
((Si,Al)
 
4
O
 
10
)(OH)
 
2
· nH
 
2
O
16.7.8Aliettite
Ca
 
0.2
Mg
 
6
((Si,Al)
 
8
O
 
20
)(OH)
 
4
· 4H
 
2
O
16.7.10Baumite
(Mg,Al,Mn,Zn,Fe)
 
3
(Si,Al)
 
2
O
 
5
(OH)
 
4

Other Names for Montmorillonite

Synonyms:
AmagorsiteDaunialiteFuller's EarthGoumbrineGumbrine
StolpeniteWalkerite (of Dana)Walkthon
Other Languages:
Catalan:Montmorillonita
Dutch:Montmorilloniet
Esperanto:Montmorijonito
French:Montmorillonite
German:Montmorillonit
Fullererde
Giliabit
Stolpenit
Hebrew:מונטמורילוניט
Hungarian:Montmorillonit
Italian:Montmorillonite
Japanese:モンモリロン石
Polish:Montmorillonit
Portuguese:Montmorillonita
Russian:Монтмориллонит
Simplified Chinese:蒙脱石
Slovak:Montmorillonit
Spanish:Montmorillonita
Stolpenita
Traditional Chinese:蒙脫石
Ukrainian:Монтморилоніт
Varieties:
AlumodeweyliteAskaniteBatrachiteCalcium-MontmorilloniteDelanovite

Other Information

Fluorescence in UV light:Usually not fluorescent, except by mixtures with autunite, etc.
Thermal Behaviour:Basal spacings collapse to lower values with dehydration
Health Warning:No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

References for Montmorillonite

Reference List:

- +
Grim, Ralph Early & G. Kulbicki (1961), Montmorillonite: high-temperature reactions and classification: American Mineralogist: 46: 1329-1369.

Tettenhorst, R. and W.D. Johns (1966), Interstratification in montmorillonite: Clays and Clay Minerals: 25: 85-93.

McAtee, J.L. & W. Henslee (1969), Electron microscopy of montmorillonite dispersed at various pH: American Mineralogist: 54: 869-874.

Shutov, V.D., V.A. Drits, and B.A. Sakharov (1969a), On the mechanism of a postsedimentary transformation of montmorillonite into hydromica. In L. Heller, Ed., Proceedings International Clay Conference, Tokyo, 1969, 1: 523-532, Jerusalem University.

Shutov, V.D., V.A. Drits, and B.A. Sakharov (1969b), On the mechanism of a postsedimentary transformation of montmorillonite into hydromica: Discussion. In L. Heller, Ed., Proceedings International Clay Conference, Tokyo, 1969, 2: 126-129, Jerusalem University.

Tettenhorst, R. and Roberson, H.E. (1973) X-ray diffraction aspects of montmorillonite. American Mineralogist: 58: 73-80.

Gillespie, J. B., J.D. Lindberg & M.S. Smith (1974), Visible and near-infrared absorption coefficients of montmorillonite and related clays: American Mineralogist: 59: 1113-1116.

Lagaly, G., M. Fernandez-Gonzalez, and A. Weiss (1976), Problems in layer-charge determination of montmorillonites: Clay Minerals: 11: 173-187.

Sherman, D.M. and N. Vergo (1988), Optical spectrum, site occupancy, and oxidation state of Mn in montmorillonite: American Mineralogist: 73: 140-144.

American Mineralogist (1989): 74: 627.

Muller, F., G. Besson, A. Manceau, and V.A. Drits (1997), Distribution of isomorphous cations within octahedral sheets in montmorillonite from Camp-Bertaux: Physica and Chemistry of Minerals: 24: 159-166.

Christidis, George 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.

Internet Links for Montmorillonite

Search Engines:
  • Look for Montmorillonite on Google
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  • External Links:
  • Look for Montmorillonite on Webmineral
  • Look for Montmorillonite on Athena Mineralogy
  • Look for Montmorillonite on Wikipedia
  • Look for Montmorillonite on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Montmorillonite details from Handbook of Mineralogy (PDF)
  • Mineral Dealers:
  • Find Montmorillonite on www.crystalclassics.co.uk
  • rare and unusual minerals mainly crystallized
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  • Fine Minerals from Weinrich Minerals, Inc.
  • Fabre Minerals - search for Montmorillonite specimens
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  • Wilensky Fine Minerals
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  • Top quality minerals from Kristalle of California
  • Specimens:The following Montmorillonite specimens are currently listed for sale on minfind.com.

    Localities for Montmorillonite

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