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Preiswerkite

A valid IMA mineral species

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Preiswerkite, etc.

Geisspfad pass, Geisspfad area, Binn, Goms, Valais, Switzerland

Preiswerkite

Geisspfad pass, Geisspfad area, Binn, Goms, Valais, Switzerland

Preiswerkite

Geisspfad area, Binn, Goms, Valais, Switzerland

Preiswerkite, etc.

Geisspfad pass, Geisspfad area, Binn, Goms, Valais, Switzerland

Preiswerkite

Geisspfad pass, Geisspfad area, Binn, Goms, Valais, Switzerland

Preiswerkite

Geisspfad area, Binn, Goms, Valais, Switzerland

Preiswerkite, etc.

Geisspfad pass, Geisspfad area, Binn, Goms, Valais, Switzerland

Preiswerkite

Geisspfad pass, Geisspfad area, Binn, Goms, Valais, Switzerland

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About PreiswerkiteHide

Heinrich Preiswerk

Formula:

NaMg₂Al(Al₂Si₂O₁₀)(OH)₂

Colour:

Pale green to colourless

Hardness:

2½

Specific Gravity:

2.96

Crystal System:

Monoclinic

Member of:

Trioctahedral mica Group > Mica Group

Name:

Named by H.R. Keusen and T. Peters in 1980 in honor of Heinrich Preiswerk (19 May 1876 - 24 March 1940), professor in Basel, Switzerland. He spent 30 years mapping the Simplon-Binntal region and the mountains of Ticino.

Type Locality:

ⓘ Geisspfad pass, Geisspfad area, Binn, Goms, Valais, Switzerland

A relatively rare sodic trioctahedral mica.

Chemically similar to dravite.

Unique IdentifiersHide

Mindat ID:

3279

Long-form identifier:

mindat:1:1:3279:3

IMA Classification of PreiswerkiteHide

IMA status:

Approved

IMA Formula:

NaAlMg₂(Si₂Al₂)O₁₀(OH)₂

First published:

1980

Type description reference:

Keusen, H. R., Peters, Tj. (1980) Preiswerkite, an Al-rich trioctahedral sodium mica from the Geisspfad ultramafic complex (Penninic Alps) American Mineralogist, 65 (11-12) 1134-1137

Classification of PreiswerkiteHide

Strunz-mindat (2026):

9.EC.20

9 : SILICATES (Germanates)
E : Phyllosilicates
C : Phyllosilicates with mica sheets, composed of tetrahedral and octahedral nets

Dana 8th ed.:

71.2.2b.15

71 : PHYLLOSILICATES Sheets of Six-Membered Rings
2 : Sheets of 6-membered rings with 2:1 layers

Hey's CIM Ref.:

16.8.1

16 : Silicates Containing Aluminum and other Metals
8 : Aluminosilicates of Mg and alkalis

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.

Symbol	Source	Reference for Standard
Pwk	IMA–CNMNC	Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43
Pwk	Warr (2020)	Warr, L.N. (2020) Recommended abbreviations for the names of clay minerals and associated phases. Clay Minerals, 55, 261–264 doi:10.1180/clm.2020.30

Physical Properties of PreiswerkiteHide

Transparency:

Translucent

Colour:

Pale green to colourless

Hardness:

2½ on Mohs scale

Cleavage:

Perfect
{001}

Density:

2.96 g/cm³ (Measured) 2.94 g/cm³ (Calculated)

Optical Data of PreiswerkiteHide

Type:

Biaxial (-)

RI values:

n_α = 1.560(4) n_β = 1.614(2) n_γ = 1.615(2)

2V:

Measured: 5° to 7°, Calculated: 14°

Max. Birefringence:

δ = 0.055
Based on recorded range of RI values above.

Interference Colours:
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.

Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.

Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.

Thickness: 30 µm Order divisions

Rotation:

Surface Relief:

Moderate (positive)
Relative to Canada balsam mounting medium (n ≈ 1.537).

This shows the grain boundary and Becke line effect under plane-polarised light, based on the contrast between this mineral's average refractive index and the mounting medium. It does not take into account mineral colouration.

Focus:

In focus

Interference Figure:

This shows the idealized biaxial acute bisectrix (Bxa) interference figure - the conoscopic view for a grain cut perpendicular to the acute bisectrix, using this mineral's 2V. The two small white dots mark the melatopes - the points where the two optic axes emerge - and are shown only when they fall within the field of view. The coloured bands are isochromatics, and the dark bands are isogyres.

Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.

Thickness: 30 µm

Stage rotation: 0°

Dispersion:

r < v moderate

Chemistry of PreiswerkiteHide

Mindat Formula:

NaMg₂Al(Al₂Si₂O₁₀)(OH)₂

Element Weights:

Element	% weight
O	47.674 %
Al	20.099 %
Si	13.948 %
Mg	12.070 %
Na	5.709 %
H	0.501 %

Calculated from ideal end-member formula.

Elements listed:

Al, H, Mg, Na, O, Si - search for minerals with similar chemistry

Common Impurities:

Fe,Ca,K,H₂O

Chemical AnalysisHide

Oxide wt%:

	1	2
SiO₂	29.93 %	30.11 %
TiO₂	0.02 %
Al₂O₃	35.98 %	36.66 %
Cr₂O₃	0.04 %
FeO	6.98 %	6.15 %
MnO	0.04 %
CaO	0.16 %
MgO	14.78 %	14.47 %
BaO	0.11 %
Na₂O	7.02 %	7.16 %
K₂O	0.06 %
F	0.041 %
Cl	0.006 %
Total:	95.167 %	94.55 %

Empirical formulas:

Sample ID	Empirical Formula
2	Na_0.96 (Mg_1.50 Fe²⁺_0.36 Al_1.02)_Σ2.88(Al_1.912.09)_Σ4.00O₁₀OH₂

Sample references:

ID	Locality	Reference	Notes
1	Liset eclogite pod, Liset, Selje, Stad, Vestland, Norway	Godard, Gaston, Smith, David (1999) Preiswerkite and Na-(Mg,Fe)-margarite in eclogites. Contributions to Mineralogy and Petrology, 136 (1) 20-32 doi:10.1007/s004100050521	Analyzed with a Cameca SX-50 electronmicroprobe at the University of Paris 7.
2	Charakoma eclogite, Soufli, Evros, Eastern Macedonia and Thrace, Greece	Mposkos, E.; Baziotis, I.; Proyer, A. (2011) Pressure–temperature evolution of eclogites from the Kechros complex in the Eastern Rhodope (NE Greece). International Journal of Earth Sciences, 101 (4). 973-996 doi:10.1007/s00531-011-0699-2	EMPA analysis of a preiswerkite identified in a single composite grain inclusion in a garnet from a kyanite-eclogite.

Crystallography of PreiswerkiteHide

Crystal System:

Monoclinic

Class (H-M):

2/m - Prismatic

Space Group:

B2/b

Setting:

C2/c

Cell Parameters:

a = 5.228(7) Å, b = 9.049(10) Å, c = 9.819(12) Å
β = 100.41°

Ratio:

a:b:c = 0.578 : 1 : 1.085

Unit Cell V:

456.87 Å³ (Calculated from Unit Cell)

Twinning:

Common about [310]

Crystal StructureHide

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Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4

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CIF File Best | x | y | z | a | b | c

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Data courtesy of the American Mineralogist Crystal Structure Database. Click on an AMCSD ID to view structure

ID	Species	Reference	Link	Year	Locality	Pressure (GPa)	Temp (K)
0001621	Preiswerkite	Oberti R, Ungaretti L, Tlili A, Smith D C, Robert J-L (1993) The crystal structure of preiswerkite American Mineralogist 78 1290-1298		1993		0	293
0001620	Preiswerkite	Oberti R, Ungaretti L, Tlili A, Smith D C, Robert J-L (1993) The crystal structure of preiswerkite American Mineralogist 78 1290-1298		1993		0	293

CIF Raw Data - click here to close

data_global
_chemical_name_mineral 'Preiswerkite'
loop_
_publ_author_name
'Oberti R'
'Ungaretti L'
'Tlili A'
'Smith D C'
'Robert J-L'
_journal_name_full 'American Mineralogist'
_journal_volume 78 
_journal_year 1993
_journal_page_first 1290
_journal_page_last 1298
_publ_section_title
;
 The crystal structure of preiswerkite
 Sample: KP17
;
_database_code_amcsd 0001621
_chemical_formula_sum 'Si2 Al3.15 Mg1.85 Na.85 O12 H2'
_cell_length_a 5.228
_cell_length_b 9.049
_cell_length_c 9.819
_cell_angle_alpha 90
_cell_angle_beta 100.41
_cell_angle_gamma 90
_cell_volume 456.873
_exptl_crystal_density_diffrn      2.905
_symmetry_space_group_name_H-M 'C 1 2/m 1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  'x,-y,z'
  '1/2+x,1/2-y,z'
  '-x,y,-z'
  '1/2-x,1/2+y,-z'
  '-x,-y,-z'
  '1/2-x,1/2-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
SiT   0.57400   0.16720   0.21390   0.50000 ?
AlT   0.57400   0.16720   0.21390   0.50000 ?
Mg1   0.00000   0.50000   0.50000   0.85000 ?
Al1   0.00000   0.50000   0.50000   0.15000 ?
Mg2   0.00000   0.83020   0.50000   0.50000 ?
Al2   0.00000   0.83020   0.50000   0.50000 ?
Na   0.00000   0.00000   0.00000   0.85000 ?
O1   0.85590   0.19890   0.15840   1.00000 ?
O2   0.45300   0.00000   0.16510   1.00000 ?
O3   0.63480   0.17030   0.39050   1.00000 ?
O-h4   0.12520   0.00000   0.39890   1.00000 ?
H   0.08310   0.00000   0.29500   1.00000   0.01267
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
SiT 0.00697 0.00705 0.00236 -0.00047 0.00075 -0.00044
AlT 0.00697 0.00705 0.00236 -0.00047 0.00075 -0.00044
Mg1 0.00536 0.00456 0.00331 0.00000 0.00101 0.00000
Al1 0.00536 0.00456 0.00331 0.00000 0.00101 0.00000
Mg2 0.00656 0.00664 0.00283 0.00000 0.00101 0.00000
Al2 0.00656 0.00664 0.00283 0.00000 0.00101 0.00000
Na 0.02545 0.02489 0.00472 0.00000 0.00176 0.00000
O1 0.01259 0.01493 0.00378 0.00047 0.00277 -0.00044
O2 0.01406 0.00996 0.00331 0.00000 0.00101 0.00000
O3 0.01259 0.00996 0.00331 -0.00071 -0.00025 0.00133
O-h4 0.00951 0.03028 0.00189 0.00000 -0.00025 0.00000

X-Ray Powder DiffractionHide

Powder Diffraction Data:

d-spacing	Intensity
9.64 Å	(50)
4.52 Å	(60)
3.215 Å	(50)
2.572 Å	(100)
2.457 Å	(70)
2.149 Å	(60)
1.508 Å	(100)

Geological EnvironmentHide

Paragenetic Mode(s):

Paragenetic Mode	Earliest Age (Ga)
Stage 4b: Highly evolved igneous rocks	>3.0
37 : Layered igneous intrusions and related PGE minerals
Stage 5: Initiation of plate tectonics	<3.5-2.5
40 : Regional metamorphism (greenschist, amphibolite, granulite facies)

Type Occurrence of PreiswerkiteHide

Type Locality:

ⓘ Geisspfad pass, Geisspfad area, Binn, Goms, Valais, Switzerland

General Appearance of Type Material:

Crystals are platy, to 1 mm.

Place of Conservation of Type Material:

Natural History Museum, Bern, Switzerland, B2548.
The Natural History Museum, London, England, 1982,455.

Geological Setting of Type Material:

rodingite dike

Associated Minerals at Type Locality:

Zoisite

Reference:

Keusen, H. R., Peters, Tj. (1980) Preiswerkite, an Al-rich trioctahedral sodium mica from the Geisspfad ultramafic complex (Penninic Alps) American Mineralogist, 65 (11-12) 1134-1137

Other Language Names for PreiswerkiteHide

Dutch:Preiswerkiet

German:Preiswerkit

Russian:Прайсверкит

Simplified Chinese:铝钠云母
镁钠云母

Spanish:Preiswerkita

Relationship of Preiswerkite to other SpeciesHide

Member of:

Trioctahedral mica Group > Mica Group

Other Members of Trioctahedral mica:

Aspidolite	NaMg₃(AlSi₃O₁₀)(OH)₂	Mon. 2/m : B2/m
Balestraite	KLi₂V⁵⁺Si₄O₁₂	Mon. 2 : B2
Biotite	K(Fe²⁺/Mg)₂(Al/Fe³⁺/Mg/Ti)([Si/Al/Fe]₂Si₂O₁₀)(OH/F)₂
Ephesite	NaLiAl₂(Al₂Si₂O₁₀)(OH)₂	Tric. 1 : P1
Garmite	CsLiMg₂(Si₄O₁₀)F₂	Mon.
Hendricksite	KZn₃(Si₃Al)O₁₀(OH)₂	Mon. 2/m : B2/m
Kreiterite	CsLi₂Fe³⁺(Si₄O₁₀)F₂	Mon.
Lepidolite	A field name for the group of Li-rich micas in, or close to, the so-called Polylithionite-Trilithionite ...
Masutomilite	K(LiAlMn²⁺)[AlSi₃O₁₀]F₂	Mon. 2 : B2
Norrishite	KLiMn³⁺₂(Si₄O₁₀)O₂	Mon. 2/m : B2/m
Orlovite	KLi₂Ti(Si₄O₁₀)OF	Mon. 2 : B2
Shirokshinite	K(NaMg₂)(Si₄O₁₀)F₂	Mon. 2/m : B2/m
Shirozulite	KMn²⁺₃(Si₃Al)O₁₀(OH)₂	Mon. 2/m : B2/m
Sokolovaite	CsLi₂Al(Si₄O₁₀)F₂	Mon.
Suhailite	(NH₄)Fe²⁺₃(AlSi₃O₁₀)(OH)₂	Mon. 2/m : B2/m
Tainiolite	KLiMg₂(Si₄O₁₀)F₂	Mon. 2/m : B2/m
Wonesite	(Na,K,◻)(Mg,Fe,Al)₆(Si,Al)₈O₂₀(OH,F)₄	Mon. 2/m : B2/m
'Zinnwaldite'	Mica Group.

Common AssociatesHide

Associations Based on Photo Data:

3 photos of Preiswerkite associated with Pargasite	NaCa₂(Mg₄Al)(Si₆Al₂)O₂₂(OH)₂
3 photos of Preiswerkite associated with Zoisite	(CaCa)(AlAlAl)O[Si₂O₇][SiO₄](OH)
3 photos of Preiswerkite associated with 'Magnesiotaramite'	{Na}{CaNa}{Mg₃AlFe³⁺}(Al₂Si₆O₂₂)(OH)₂
3 photos of Preiswerkite associated with 'Ruby'	Al₂O₃

Related Minerals - Strunz-mindat Grouping Hide

9.EC.	Meifuite	KFe₆(Si₇Al)O₁₉(OH)₄Cl₂	Tric. 1 : P1
9.EC.	Balestraite	KLi₂V⁵⁺Si₄O₁₂	Mon. 2 : B2
9.EC.	Voloshinite	Rb(LiAl_1.5◻_0.5)(Al_0.5Si_3.5)O₁₀F₂	Mon. 2/m : B2/b
9.EC.05	Talc	Mg₃Si₄O₁₀(OH)₂	Tric. 1 : P1
9.EC.05	Minnesotaite	Fe²⁺₃Si₄O₁₀(OH)₂	Tric. 1 : P1
9.EC.05	Willemseite	Ni₃Si₄O₁₀(OH)₂	Mon.
9.EC.10	Fluorluanshiweiite	KLiAl_1.5(Si_3.5Al_0.5)O₁₀F₂	Mon. 2/m : B2/m
9.EC.10	Garmite	CsLiMg₂(Si₄O₁₀)F₂	Mon.
9.EC.10	Gorbunovite	CsLi₂(Ti,Fe)Si₄O₁₀(F,OH,O)₂	Mon.
9.EC.10	Ferripyrophyllite	Fe³⁺Si₂O₅(OH)	Mon. 2/m
9.EC.10	Manganiceladonite	K(MgMn³⁺◻)(Si₄O₁₀)(OH)₂	Mon.
9.EC.10	Luanshiweiite	KLiAl_1.5(Si_3.5Al_0.5)O₁₀(OH)₂	Mon. 2/m : B2/b
9.EC.10	Pyrophyllite	Al₂Si₄O₁₀(OH)₂	Tric. 1
9.EC.15	Paragonite	NaAl₂(AlSi₃O₁₀)(OH)₂	Mon.
9.EC.15	Ferroaluminoceladonite	K(Fe²⁺Al◻)(Si₄O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.15	Nanpingite	CsAl₂(AlSi₃O₁₀)(OH,F)₂	Mon. 2/m : B2/b
9.EC.15	Ferroceladonite	K(Fe²⁺Fe³⁺◻)(Si₄O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.15	Ganterite	Ba_0.5(Na,K)_0.5Al₂(Si_2.5Al_1.5)O₁₀(OH)₂	Mon. 2/m : B2/b
9.EC.15	Kreiterite	CsLi₂Fe³⁺(Si₄O₁₀)F₂	Mon.
9.EC.15	Roscoelite	KV³⁺₂(AlSi₃O₁₀)(OH)₂	Mon. 2/m : B2/b
9.EC.15	Aluminoceladonite	K(MgAl◻)(Si₄O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.15	Tobelite	(NH₄)Al₂(AlSi₃O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.15	Tainiolite	KLiMg₂(Si₄O₁₀)F₂	Mon. 2/m : B2/m
9.EC.15	Celadonite	K(MgFe³⁺◻)(Si₄O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.15	Chromceladonite	K(MgCr◻)(Si₄O₁₀)(OH)₂	Mon. 2 : B2
9.EC.15	Montdorite	KFe²⁺_1.5Mn²⁺_0.5Mg_0.5Si₄O₁₀(F,OH)₂	Mon. 2/m : B2/m
9.EC.15	Chromphyllite	KCr₂(AlSi₃O₁₀)(OH)₂	Mon. 2/m : B2/b
9.EC.15	Boromuscovite	KAl₂(BSi₃O₁₀)(OH)₂	Mon. 2/m
9.EC.15	'UM1988-22-SiO:AlCaFFeHKLiMg'	KLiMgAl₂Si₃O₁₀F₂	Mon.
9.EC.15	Chernykhite	(Ba,Na)(V³⁺,Al,Mg)₂((Si,Al)₄O₁₀)(OH)₂	Mon.
9.EC.15	Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂	Mon. 2/m : B2/b
9.EC.20	Masutomilite	K(LiAlMn²⁺)[AlSi₃O₁₀]F₂	Mon. 2 : B2
9.EC.20	Oxyphlogopite	K(Mg,Ti,Fe)₃[(Si,Al)₄O₁₀](O,F)₂	Mon. 2/m : B2/m
9.EC.20	'Chloroferrokinoshitalite'	(Ba,K)(Fe²⁺,Mg)₃(Al₂Si₂O₁₀)(Cl,OH,F)₂
9.EC.20	Siderophyllite	KFe²⁺₂Al(Al₂Si₂O₁₀)(OH)₂	Mon.
9.EC.20	Sokolovaite	CsLi₂Al(Si₄O₁₀)F₂	Mon.
9.EC.20	Hendricksite	KZn₃(Si₃Al)O₁₀(OH)₂	Mon. 2/m : B2/m
9.EC.20	Tetraferriphlogopite	KMg₃(Si₃Fe³⁺)O₁₀(OH)₂	Mon. 2/m : B2/m
9.EC.20	Fluorannite	KFe²⁺₃(Si₃Al)O₁₀F₂	Mon. 2/m : B2/m
9.EC.20	Aspidolite	NaMg₃(AlSi₃O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.20	Suhailite	(NH₄)Fe²⁺₃(AlSi₃O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.20	Ephesite	NaLiAl₂(Al₂Si₂O₁₀)(OH)₂	Tric. 1 : P1
9.EC.20	Norrishite	KLiMn³⁺₂(Si₄O₁₀)O₂	Mon. 2/m : B2/m
9.EC.20	Phlogopite	KMg₃(AlSi₃O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.20	Yangzhumingite	KMg_2.5(Si₄O₁₀)F₂	Mon. 2/m : B2/m
9.EC.20	Orlovite	KLi₂Ti(Si₄O₁₀)OF	Mon. 2 : B2
9.EC.20	Tetraferriannite	KFe²⁺₃(Si₃Fe³⁺)O₁₀(OH)₂	Mon. 2/m : B2/m
9.EC.20	Shirokshinite	K(NaMg₂)(Si₄O₁₀)F₂	Mon. 2/m : B2/m
9.EC.20	Trilithionite	K(Li_1.5Al_1.5)(AlSi₃O₁₀)(F,OH)₂	Mon. 2/m : B2/b
9.EC.20	Polylithionite	KLi₂Al(Si₄O₁₀)(F,OH)₂	Mon. 2/m : B2/b
9.EC.20	Shirozulite	KMn²⁺₃(Si₃Al)O₁₀(OH)₂	Mon. 2/m : B2/m
9.EC.20	Fluorophlogopite	KMg₃(Si₃Al)O₁₀F₂	Mon. 2/m : B2/m
9.EC.20	Wonesite	(Na,K,◻)(Mg,Fe,Al)₆(Si,Al)₈O₂₀(OH,F)₄	Mon. 2/m : B2/m
9.EC.20	'UM2004-49-SiO:AlCsFHKLi'	(Cs,K)(Al,Li)_2.6((Si,Al)₄O₁₀)(F,OH)₂
9.EC.20	Fluorotetraferriphlogopite	KMg₃(Fe³⁺Si₃O₁₀)F₂	Mon. 2/m : B2/m
9.EC.20	Annite	KFe²⁺₃(AlSi₃O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.20	Eastonite	KMg₂Al(Al₂Si₂O₁₀)(OH)₂	Mon.
9.EC.22	'Pimelite'	Ni₃Si₄O₁₀(OH)₂ · 4H₂O	Hex.
9.EC.30	Margarite	CaAl₂(Al₂Si₂O₁₀)(OH)₂	Mon. 2/m : B2/b
9.EC.35	Kinoshitalite	(Ba,K)(Mg,Mn²⁺,Al)₃(Al₂Si₂O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.35	Ferrokinoshitalite	(Ba,K)(Fe²⁺,Mg)₃(Al₂Si₂O₁₀)(OH,F)₂	Mon. 2/m : B2/m
9.EC.35	Clintonite	CaAlMg₂(SiAl₃O₁₀)(OH)₂	Mon. 2/m : B2/m
9.EC.35	Oxykinoshitalite	(Ba,K)(Mg,Ti,Fe³⁺,Fe²⁺)₃((Si,Al)₄O₁₀)(O,OH,F)₂	Mon. 2/m : B2/m
9.EC.35	Fluorokinoshitalite	BaMg₃(Al₂Si₂O₁₀)F₂	Mon. 2/m : B2/m
9.EC.35	Bityite	CaLiAl₂(AlBeSi₂O₁₀)(OH)₂	Mon. 2/m : B2/b
9.EC.35	Anandite	(Ba,K)(Fe²⁺,Mg)₃((Si,Al,Fe)₄O₁₀)(S,OH)₂	Mon. 2/m : B2/b
9.EC.40	Montmorillonite	(Na,Ca)_0.33(Al,Mg)₂(Si₄O₁₀)(OH)₂ · nH₂O	Mon. 2/m : B2/m
9.EC.40	Beidellite	(Na,Ca_0.5)_0.3Al₂((Si,Al)₄O₁₀)(OH)₂ · nH₂O	Mon. 2/m : B2/m
9.EC.40	Volkonskoite	Ca_0.3(Cr,Mg,Fe)₂((Si,Al)₄O₁₀)(OH)₂ · 4H₂O	Mon.
9.EC.40	Nontronite	Na_0.3Fe₂((Si,Al)₄O₁₀)(OH)₂ · nH₂O	Mon. 2/m : B2/m
9.EC.40	Kurumsakite	(Zn,Ni,Cu)₈Al₈V⁵⁺₂Si₅O₃₅ · 27H₂O (?)	Orth.
9.EC.40	Yakhontovite	(Ca,Na)_0.5(Cu,Fe,Mg)₂(Si₄O₁₀)(OH)₂ · 3H₂O	Mon.
9.EC.45	Swinefordite	Li(Al,Li,Mg)₃((Si,Al)₄O₁₀)₂(OH,F)₄ · nH₂O	Mon. 2/m : B2/m
9.EC.45	Hectorite	Na_0.3(Mg,Li)₃(Si₄O₁₀)(F,OH)₂	Mon. 2/m : B2/m
9.EC.45	Zincsilite	Zn₃Si₄O₁₀(OH)₂ · 4H₂O (?)	Mon.
9.EC.45	Hanjiangite	Ba₂CaV³⁺Al(H₂AlSi₃O₁₂)(CO₃)₂F	Mon. 2 : B2
9.EC.45	Spadaite	MgSiO₂(OH)₂ · H₂O (?)
9.EC.45	Ferrosaponite	Ca_0.3(Fe²⁺,Mg,Fe³⁺)₃((Si,Al)₄O₁₀)(OH)₂ · 4H₂O	Mon.
9.EC.45	Stevensite	(Ca,Na)_xMg_3-x(Si₄O₁₀)(OH)₂	Mon.
9.EC.45	Saponite	Ca_0.25(Mg,Fe)₃((Si,Al)₄O₁₀)(OH)₂ · nH₂O	Mon.
9.EC.45	Sauconite	Na_0.3Zn₃((Si,Al)₄O₁₀)(OH)₂ · 4H₂O	Mon.
9.EC.50	Vermiculite	Mg_0.7(Mg,Fe,Al)₆(Si,Al)₈O₂₀(OH)₄ · 8H₂O	Mon. 2/m
9.EC.52	'Tarasovite'	near NaKAl₁₁Si₁₃O₄₀(OH)₉ · 3H₂O
9.EC.55	Clinochlore	Mg₅Al(AlSi₃O₁₀)(OH)₈	Mon. 2/m : B2/m
9.EC.55	Borocookeite	(LiAl₄◻)[BSi₃O₁₀](OH)₈	Mon. m : Bb
9.EC.55	Franklinfurnaceite	Ca₂Fe³⁺Mn²⁺₃Mn³⁺(Zn₂Si₂O₁₀)(OH)₈	Mon. 2 : B2
9.EC.55	Pennantite	Mn²⁺₅Al(AlSi₃O₁₀)(OH)₈	Tric.
9.EC.55	Vakhrushevaite	Mg₅Cr(AlSi₃O₁₀)(OH)₈	Tric. 1
9.EC.55	Nimite	Ni₅Al(AlSi₃O₁₀)(OH)₈	Mon. 2/m : B2/m
9.EC.55	Cookeite	(LiAl₄◻)[AlSi₃O₁₀](OH)₈	Mon. 2/m
9.EC.55	Gonyerite	Mn²⁺₅Fe³⁺(Fe³⁺Si₃O₁₀)(OH)₈	Orth.
9.EC.55	Chamosite	Fe²⁺₅Al(AlSi₃O₁₀)(OH)₈	Mon. 2/m : B2/m
9.EC.55	'Orthochamosite'	(Fe²⁺,Mg,Fe³⁺)₅Al(AlSi₃O₁₀)(OH,O)₈
9.EC.55	Baileychlore	Zn₅Al(AlSi₃O₁₀)(OH)₈	Tric. 1
9.EC.55	Sudoite	Mg₂Al₃(AlSi₃O₁₀)(OH)₈	Mon. 2/m : B2/m
9.EC.55	Glagolevite	Na(Mg,Al)₆(AlSi₃O₁₀)(OH,O)₈	Tric. 1 : P1
9.EC.55	Donbassite	Al_4.33(AlSi₃O₁₀)(OH)₈	Mon. 2 : B2
9.EC.60	Dozyite	Mg₇Al₂(Al₂Si₄O₁₅)(OH)₁₂	Mon.
9.EC.60	Rectorite	(Na,Ca)Al₄((Si,Al)₈O₂₀)(OH)₄ · 2H₂O	Mon.
9.EC.60	Corrensite	(Mg,Fe)₉((Si,Al)₈O₂₀)(OH)₁₀ · nH₂O	Orth.
9.EC.60	Aliettite	Ca_0.2Mg₆((Si,Al)₈O₂₀)(OH)₄ · 4H₂O	Mon.
9.EC.60	Karpinskite	(Ni,Mg)₂Si₂O₅(OH)₂ (?)	Mon.
9.EC.60	Lunijianlaite	Li_0.7Al_6.2(AlSi₇O₂₀)(OH,O)₁₀	Mon.
9.EC.60	Tosudite	Na_0.5(Al,Mg)₆((Si,Al)₈O₁₈)(OH)₁₂ · 5H₂O	Mon. 2 : B2
9.EC.60	Hydrobiotite	K(Mg,Fe²⁺)₆((Si,Al)₈O₂₀)(OH)₄ · nH₂O	Mon. 2/m : B2/m
9.EC.60	Saliotite	(Li,Na)Al₃(AlSi₃O₁₀)(OH)₅	Mon. 2/m : B2/m
9.EC.60	Kulkeite	Mg₈Al(AlSi₇O₂₀)(OH)₁₀	Mon.
9.EC.60	Brinrobertsite	Na_0.3Al₄(Si₄O₁₀)₂(OH)₄ · 3.5 H₂O	Mon.
9.EC.65	Macaulayite	(Fe,Al)₂₄Si₄O₄₃(OH)₂	Mon.
9.EC.70	Burckhardtite	Pb₂(Fe³⁺Te⁶⁺)[AlSi₃O₈]O₆	Trig. 3m(32/m) : P31m
9.EC.75	Niksergievite	(Ba,Ca)₂Al₃(AlSi₃O₁₀)(CO₃)(OH)₆ · nH₂O	Mon.
9.EC.75	Ferrisurite	(Pb,Ca)_2.4Fe³⁺₂(Si₄O₁₀)(CO₃)_1.7(OH)₃ · nH₂O	Mon.
9.EC.75	Surite	(Pb,Ca)₃(Al,Fe²⁺,Mg)₂((Si,Al)₄O₁₀)(CO₃)₂(OH)₂	Mon. 2 : P2₁
9.EC.80	Kegelite	Pb₈Al₄(Si₈O₂₀)(SO₄)₂(CO₃)₄(OH)₈	Mon.

Other InformationHide

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References for PreiswerkiteHide

Reference List:

Keusen, H. R., Peters, Tj. (1980) Preiswerkite, an Al-rich trioctahedral sodium mica from the Geisspfad ultramafic complex (Penninic Alps) American Mineralogist, 65 (11-12) 1134-1137

Holdaway, M.J. (1981) ERRATA. American Mineralogist, 66 (11-12). 1281

Tlili, A., Smith, D. C., Beny, J.-M., Boyer, H. (1989) A Raman microprobe study of natural micas. Mineralogical Magazine, 53 (370) 165-179 doi:10.1180/minmag.1989.053.370.04

Oberti, Roberta, Ungaretti, Luciano, Tlili, Ali, Smith, David C., Robert, Jean-louis (1993) The crystal structure of preiswerkite. American Mineralogist, 78 (11-12) 1290-1298

Rieder, M., Cavazzini, G., D’Yakonov, Y.S., Frank-Kamenetskii, V.A., Gottardt, G., Guggenheim, S., Koval, P.V., Muller, G., Neiva, A.M.R., Radoslovich, E.W., Robert, J.L., Sassi, F.P., Takeda, H., Weiss, Z., Wones, D.R. (1998) Nomenclature of the micas. The Canadian Mineralogist, 36 (3) 905-912

Godard, Gaston, Smith, David (1999) Preiswerkite and Na-(Mg,Fe)-margarite in eclogites. Contributions to Mineralogy and Petrology, 136 (1) 20-32 doi:10.1007/s004100050521

Visser, Diederik; Nijland, Timo G.; Lieftink, Dick J.; Maijer, Cees (1999) The occurrence of preiswerkite in a tourmaline-biotite-scapolite rock from Blengsvatn, Norway. American Mineralogist, 84 (5). p.977-982.

(2001) Preiswerkite. Handbook of Mineralogy. Mineralogical Society of America

Roth, P. (2007) Preiswerkite. in Minerals first discovered in Switzerland and minerals named after Swiss individuals, Kristallografik Verlag (Achberg Germany): 122-123.

Localities for PreiswerkiteHide

Showing 19 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the

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Locality ListHide

- This locality has map coordinates listed.

- This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality.

- Good crystals or important locality for species.

- World class for species or very significant. (TL) - Type Locality for a valid mineral species. (FRL) - First Recorded Locality for everything else (eg varieties). ~~Struck out~~ - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.


Botswana
North-East District ⓘ Vumba Hills	Godard et al. (1999)

China
Anhui Anqing Yuexi County ⓘ Changpu	...

France
Pays de la Loire Loire-Atlantique Nantes Saint-Philbert-de-Grand-Lieu ⓘ La Compointrie	Mposkos et al. (2012)

Greece
Eastern Macedonia and Thrace Evros Soufli ⓘ Charakoma eclogite	Mposkos et al. (2011)
Rhodope Arriana ⓘ Kechros	Mposkos et al. (2012)

Guatemala
Motagua Valley ⓘ Sierra de las Minas	Ostrooumov et al. (2010)
Zacapa Department ⓘ Río La Palmilla	Godard et al. (1999)

Japan
Niigata Prefecture ⓘ Itoigawa City	ID by Dr. Miyajima

Kyrgyzstan
Chuy Region Kemin District ⓘ Aqtyuz eclogite	Orozbaev et al. (2011)

Norway
Agder Froland ⓘ Blengsvatn	Visser et al. (1999)
Vestland Stad Selje Liset ⓘ Liset eclogite pod	Smith et al. (1983) +1 other reference

Switzerland (TL)
Valais Goms Binn Geisspfad area ⓘ Geisspfad pass (TL)	Keusen et al. (1980) +1 other reference
Visp Saas-Almagell ⓘ Allalin area	Stalder et al. (1998)
ⓘ Allalinhorn	Godard et al. (1999)

USA
ⓘ North Carolina	Leonard S.Wiener and Sigrid Ballew
Clay County Buck Creek ⓘ Buck Creek Mine (Cullakenee Mine)	Genth (1891)
ⓘ Shooting Creek	Dana et al. (1892)
Macon County Cowee Valley Ellijay Mining District Franklin Corundum Hill ⓘ Culsagee Mine	Genth (1891)

Vietnam
Yên Bái Province Lục Yên District ⓘ Luc Yen Mine	Krivovichev et al. (2022)

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Preiswerkite

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