Windmountainite
A valid IMA mineral species
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About Windmountainite
Formula:
◻Fe3+2Mg2◻2Si8O20(OH)2(H2O)4 · 4H2O
Colour:
Orange-brown
Lustre:
Silky, Dull
Hardness:
2
Specific Gravity:
2.51 (Calculated)
Crystal System:
Monoclinic
Member of:
Name:
Named for Wind Mountain, New Mexico, USA, the type locality.
"Associated minerals include albite, aegirine, fluorapophyllite-(K), natrolite, neotocite, and montmorillonite, the last of these being observed to replace primary windmountainite. It has a dull luster, silky in aggregates, is translucent and has an orange-brown streak. It does not fluoresce under short-, medium-, or long-wave ultraviolet radiation." (Leung & McDonald, 2020).
Unique Identifiers
Mindat ID:
53877
Long-form identifier:
mindat:1:1:53877:6
IMA Classification of Windmountainite
Approved
IMA Formula:
◻Fe3+2Mg2Si8O20(OH)2·8H2O
Approval year:
2019
First published:
2020
Type description reference:
Leung, Derek D., McDonald, Andrew M. (2020) Windmountainite, □Fe3+2Mg2□2Si8O20(OH)2(H2O)4·4H2O, a new modulated, layered Fe3+-Mg-silicate-hydrate from Wind Mountain, New Mexico: Characterization and origin, with comments on the classification of palygorskite-group minerals. The Canadian Mineralogist, 58 (4) 477-509 doi:10.3749/canmin.1900063
Classification of Windmountainite
9.EE.20
9 : SILICATES (Germanates)
E : Phyllosilicates
E : Single tetrahedral nets of 6-membered rings connected by octahedral nets or octahedral bands
9 : SILICATES (Germanates)
E : Phyllosilicates
E : Single tetrahedral nets of 6-membered rings connected by octahedral nets or octahedral bands
Mineral Symbols
As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.
| Symbol | Source | Reference for Standard |
|---|---|---|
| Wmt | IMA–CNMNC | Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43 |
Physical Properties of Windmountainite
Silky, Dull
Transparency:
Translucent
Comment:
Silky in aggregates
Colour:
Orange-brown
Streak:
Orange-brown
Hardness:
2 on Mohs scale
Hardness Data:
Estimated
Tenacity:
Brittle
Cleavage:
Distinct/Good
Two good cleavages (predicted) on {110}
Two good cleavages (predicted) on {110}
Fracture:
Splintery
Density:
2.51 g/cm3 (Calculated)
Chemistry of Windmountainite
Mindat Formula:
◻Fe3+2Mg2◻2Si8O20(OH)2(H2O)4 · 4H2O
Element Weights:
Crystallography of Windmountainite
Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
B2/m
Setting:
C2/m
Cell Parameters:
a = 13.759(3) Å, b = 17.911(4) Å, c = 5.274(1) Å
β = 106.44(3)°
β = 106.44(3)°
Ratio:
a:b:c = 0.768 : 1 : 0.294
Unit Cell V:
1,246.57 ų (Calculated from Unit Cell)
Morphology:
Acicular to bladed crystals, elongate on [001] and flattened on the pinacoid {010}.
X-Ray Powder Diffraction
Powder Diffraction Data:
| d-spacing | Intensity |
|---|---|
| 10.592 Å | (100) |
| 5.453 Å | (16) |
| 4.484 Å | (19) |
| 4.173 Å | (28) |
| 3.319 Å | (53) |
| 3.271 Å | (13) |
| 2.652 Å | (30) |
| 2.530 Å | (27) |
Reference:
Leung, Derek D., McDonald, Andrew M. (2020) Windmountainite, □Fe3+2Mg2□2Si8O20(OH)2(H2O)4·4H2O, a new modulated, layered Fe3+-Mg-silicate-hydrate from Wind Mountain, New Mexico: Characterization and origin, with comments on the classification of palygorskite-group minerals. The Canadian Mineralogist, 58 (4) 477-509 doi:10.3749/canmin.1900063
Geological Environment
Paragenetic Mode(s):
| Paragenetic Mode | Earliest Age (Ga) |
|---|---|
| Stage 4b: Highly evolved igneous rocks | >3.0 |
| 35 : Ultra-alkali and agpaitic igneous rocks |
Type Occurrence of Windmountainite
General Appearance of Type Material:
Orange-brown, radiating aggregates. Tightly bound bundles (up to 0.02 × 6 mm) of acicular to bladed crystals.
Place of Conservation of Type Material:
Type material is deposited in the mineralogical collections of the Canadian Museum of Nature, P.O. Box 3443, Station D, Ottawa, Ontario K1P 6P4, Canada, catalogue number CMNMC 87260
Geological Setting of Type Material:
Phonolite dike
Associated Minerals at Type Locality:
Reference:
Leung, Derek D., McDonald, Andrew M. (2020) Windmountainite, □Fe3+2Mg2□2Si8O20(OH)2(H2O)4·4H2O, a new modulated, layered Fe3+-Mg-silicate-hydrate from Wind Mountain, New Mexico: Characterization and origin, with comments on the classification of palygorskite-group minerals. The Canadian Mineralogist, 58 (4) 477-509 doi:10.3749/canmin.1900063
Synonyms of Windmountainite
Other Language Names for Windmountainite
Dutch:Windmountainiet
German:Windmountainit
Relationship of Windmountainite to other Species
Member of:
Other Members of Palygorskite Group:
| Ikorskyite | KMn3+(Si4O10) · 3H2O | Mon. 2/m : P21/b |
| Palygorskite | ◻Al2Mg2◻2Si8O20(OH)2(H2O)4 · 4H2O | Mon. 2/m : B2/m |
| Raite | Mn2+Mn2+2Na2(◻1.75Ti0.25)Si8O20(OH)2(H2O)4 · Na(H2O)6 | Orth. 222 : C222 |
| Tuperssuatsiaite | Fe3+Fe3+2(Na◻)◻2Si8O20(OH)2(H2O)4 · 2H2O | Mon. 2/m : B2/m |
| 'Unnamed (Na-Ca-Fe-Silicate-Hydrate)' | NaCa(Fe2+,Al,Mn)5[Si8O19(OH)](OH)7 · 5H2O | Tric. 1 : P1 |
| Windhoekite | Fe3+(Fe3+1.67◻0.33)Ca2◻2Si8O20(OH)2(H2O)4(OH)2 · 6H2O | Mon. 2/m : B2/m |
| Yofortierite | Mn2+Mn2+2Mn2+2◻2Si8O20(OH)2(H2O)4 · 4H2O | Mon. 2/m : B2/m |
Common Associates
Associations Based on Photo Data:
Related Minerals - Strunz-mindat Grouping
| 9.EE. | Cairncrossite | Sr2Ca7-xNa2x(Si4O10)4(OH)2(H2O)15-x |
| 9.EE.05 | Bementite | Mn7Si6O15(OH)8 |
| 9.EE.07 | Innsbruckite | Mn33(Si2O5)14(OH)38 |
| 9.EE.10 | 'Brokenhillite' | Mn8Si6O15(OH)10 |
| 9.EE.10 | Mcgillite | (Mn,Fe)8Si6O15(OH)8Cl2 |
| 9.EE.10 | Friedelite | Mn2+8Si6O15(OH,Cl)10 |
| 9.EE.10 | Pyrosmalite-(Mn) | Mn2+8Si6O15(OH,Cl)10 |
| 9.EE.10 | Pyrosmalite-(Fe) | Fe2+8Si6O15(OH,Cl)10 |
| 9.EE.15 | Nelenite | Mn2+16As3+3Si12O36(OH)17 |
| 9.EE.15 | Schallerite | Mn2+16As3Si12O36(OH)17 |
| 9.EE.20 | Palygorskite | ◻Al2Mg2◻2Si8O20(OH)2(H2O)4 · 4H2O |
| 9.EE.20 | Yofortierite | Mn2+Mn2+2Mn2+2◻2Si8O20(OH)2(H2O)4 · 4H2O |
| 9.EE.20 | Windhoekite | Fe3+(Fe3+1.67◻0.33)Ca2◻2Si8O20(OH)2(H2O)4(OH)2 · 6H2O |
| 9.EE.20 | Ikorskyite | KMn3+(Si4O10) · 3H2O |
| 9.EE.20 | Tuperssuatsiaite | Fe3+Fe3+2(Na◻)◻2Si8O20(OH)2(H2O)4 · 2H2O |
| 9.EE.20 | 'Unnamed (Na-Ca-Fe-Silicate-Hydrate)' | NaCa(Fe2+,Al,Mn)5[Si8O19(OH)](OH)7 · 5H2O |
| 9.EE.25 | Sepiolite | Mg4(Si6O15)(OH)2 · 6H2O |
| 9.EE.25 | Loughlinite | Na2Mg3Si6O16 · 8H2O |
| 9.EE.25 | Falcondoite | (Ni,Mg)4Si6O15(OH)2 · 6H2O |
| 9.EE.25 | Kalifersite | (K,Na)5Fe3+7Si20O50(OH)6 · 12H2O |
| 9.EE.30 | Orlymanite | Ca4Mn3Si8O20(OH)6 · 2H2O |
| 9.EE.30 | Tungusite | Ca4Fe2Si6O15(OH)6 |
| 9.EE.30 | Gyrolite | NaCa16Si23AlO60(OH)8 · 14H2O |
| 9.EE.35 | Reyerite | (Na,K)2Ca14(Si,Al)24O58(OH)8 · 6H2O |
| 9.EE.35 | Kodamaite | Na3(Ca5Na)Si16O36(OH)4F2 · (14-x)H2O |
| 9.EE.35 | Truscottite | (Ca,Mn)14Si24O58(OH)8 · 2H2O |
| 9.EE.40 | Natrosilite | Na2Si2O5 |
| 9.EE.45 | Makatite | Na2Si4O8(OH)2 · 4H2O |
| 9.EE.50 | Varennesite | Na8Mn2Si10O25(OH,Cl)2 · 12H2O |
| 9.EE.55 | Raite | Mn2+Mn2+2Na2(◻1.75Ti0.25)Si8O20(OH)2(H2O)4 · Na(H2O)6 |
| 9.EE.60 | Intersilite | Na6Mn2+Ti[Si10O24(OH)](OH)3 · 4H2O |
| 9.EE.65 | Zakharovite | Na4Mn5Si10O24(OH)6 · 6H2O |
| 9.EE.65 | Shafranovskite | Na3K2(Mn,Fe,Na)4[Si9(O,OH)27](OH)2 · nH2O |
| 9.EE.70 | Zeophyllite | Ca13Si10O28(OH)2F8 · 6H2O |
| 9.EE.75 | Minehillite | (K,Na)2-3Ca28Zn4Al4Si40O112(OH)16 |
| 9.EE.80 | Fedorite | (Na,K)2-3(Ca4Na3)Si16O38(OH,F)2 · 3.5H2O |
| 9.EE.80 | Martinite | (Na,◻,Ca)12Ca4(Si,S,B)14B2O38(OH,Cl)2F2 · 4H2O |
| 9.EE.80 | Ellingsenite | Na5Ca6Si18O38(OH)13 · 6H2O |
| 9.EE.85 | Lalondeite | (Na,Ca)6(Ca,Na)3Si16O38(F,OH)2 · 3H2O |
Fluorescence of Windmountainite
Does not fluoresce
Other Information
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.
Internet Links for Windmountainite
mindat.org URL:
https://www.mindat.org/min-53877.html
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References for Windmountainite
Reference List:
Miyawaki, Ritsuro, Hatert, Frédéric, Pasero, Marco, Mills, Stuart J. (2019) IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) NEWSLETTER 51. European Journal of Mineralogy, 31 (5-6) 1099-1104 doi:10.1127/ejm/2019/0031-2894
Leung, Derek D., McDonald, Andrew M. (2020) Windmountainite, □Fe3+2Mg2□2Si8O20(OH)2(H2O)4·4H2O, a new modulated, layered Fe3+-Mg-silicate-hydrate from Wind Mountain, New Mexico: Characterization and origin, with comments on the classification of palygorskite-group minerals. The Canadian Mineralogist, 58 (4) 477-509 doi:10.3749/canmin.1900063
Localities for Windmountainite
Showing 2 localities.
symbol to view information about a locality.
The Locality List
- 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).
All localities listed without proper references should be considered as questionable.
Namibia | |
| Weissman (2021) |
USA (TL) | |
| Miyawaki et al. (2019) +1 other reference |
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Wind Mountain, Cornudas Mountains, Otero County, New Mexico, USA