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Mendozite

A valid IMA mineral species - grandfathered
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About MendoziteHide

08592580017271925081525.jpg
Flag of Mendoza province, Argentina
Formula:
NaAl(SO4)2 · 11H2O
Colour:
Colourless (turns white upon exposure); colourless in transmitted light.
Hardness:
3
Specific Gravity:
1.730
Crystal System:
Monoclinic
Name:
Named after the province of Mendoza, Argentina, that includes the supposed type locality of St. Juan.

Closely related to the members of the Alum Group.


Unique IdentifiersHide

Mindat ID:
2643
Long-form identifier:
mindat:1:1:2643:3

IMA Classification of MendoziteHide

Approved, 'Grandfathered' (first described prior to 1959)
IMA Formula:
NaAl(S6+O4)2·11H2O

Classification of MendoziteHide

7.CC.15

7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
C : Sulfates (selenates, etc.) without additional anions, with H2O
C : With medium-sized and large cations
29.5.4.1

29 : HYDRATED ACID AND NORMAL SULFATES
5 : AB(XO4)2·xH2O
25.6.13

25 : Sulphates
6 : Sulphates of Al and Tl

Mineral SymbolsHide

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

SymbolSourceReference for Standard
MzIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of MendoziteHide

Transparency:
Transparent
Colour:
Colourless (turns white upon exposure); colourless in transmitted light.
Hardness:
Cleavage:
Distinct/Good
{100}, good; {001} and {010}, indistinct.
Density:
1.730 g/cm3 (Measured)    1.781 g/cm3 (Calculated)

Optical Data of MendoziteHide

Type:
Biaxial (-)
RI values:
nα = 1.449(1) nβ = 1.461(3) nγ = 1.463(3)
2V:
Measured: 56° (1), Calculated: 44°
Max. Birefringence:
δ = 0.014
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.

Surface Relief:
Moderate
Dispersion:
r > v distinct

Chemistry of MendoziteHide

Mindat Formula:
NaAl(SO4)2 · 11H2O
Element Weights:
Element% weight
O69.047 %
S14.566 %
Al6.129 %
Na5.222 %
H5.037 %

Calculated from ideal end-member formula.

Crystallography of MendoziteHide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
B2/b
Setting:
C2/c
Cell Parameters:
a = 21.75(3) Å, b = 9.11(1) Å, c = 8.30(1) Å
β = 92.28(5)°
Ratio:
a:b:c = 2.387 : 1 : 0.911
Unit Cell V:
1,643.28 ų (Calculated from Unit Cell)
Z:
4
Morphology:
Artificial crystals are prismatic [001] with large {100}; also pseudo-rhombohedral with {100} and {211}. Fibrous masses.

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0000289MendoziteFang J H, Robinson P D (1972) Crystal structures and mineral chemistry of double-salt hydrates: II. The crystal structure of mendozite, NaAl(SO4)2.11H2O American Mineralogist 57 1081-108819720293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
3.50 Å(100)
4.76 Å(85)
4.58 Å(65)
4.15 Å(50)
3.60 Å(35)
2.644 Å(35)
10.9 Å(30)
Comments:
synthetic

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 7: Great Oxidation Event<2.4
45a : [Sulfates, arsenates, selenates, antimonates]
47a : [Near-surface hydration of prior minerals]
47b : [Sulfates and sulfites]
Stage 10a: Neoproterozoic oxygenation/terrestrial biosphere<0.6
50 : Coal and/or oil shale minerals<0.36
Stage 10b: Anthropogenic minerals<10 Ka
55 : Anthropogenic mine minerals
56 : Slag and smelter minerals (see also #51 and #55)

Type Occurrence of MendoziteHide

Synonyms of MendoziteHide

Other Language Names for MendoziteHide

Related Minerals - Strunz-mindat GroupingHide

7.CC.CobaltoblöditeNa2Co(SO4)2 · 4H2OMon. 2/m : P21/b
7.CC.AndychristyitePbCu2+Te6+O5(H2O)Tric. 1 : P1
7.CC.Ammoniovoltaite(NH4)2Fe2+5Fe3+3Al(SO4)12(H2O)18Iso. m3m(4/m32/m) : Fd3c
7.CC.05KrausiteKFe(SO4)2 · H2OMon. 2/m : P21/m
7.CC.10TamarugiteNaAl(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.15KaliniteKAl(SO4)2 · 11H2OMon. 2/m : B2/b
7.CC.20Alum-(Na)NaAl(SO4)2 · 12H2OIso. m3(2/m3) : Pa3
7.CC.20Lonecreekite(NH4)Fe3+(SO4)2 · 12H2OIso. m3(2/m3) : Pa3
7.CC.20Alum-(K)KAl(SO4)2 · 12H2OIso. m3(2/m3) : Pa3
7.CC.20Tschermigite(NH4)Al(SO4)2 · 12H2OIso. m3(2/m3) : Pa3
7.CC.20LanmuchangiteTl+Al(SO4)2 · 12H2OIso. m3(2/m3) : Pa3
7.CC.25ZincovoltaiteK2Zn5Fe3+3Al(SO4)12 · 18H2OIso. m3m(4/m32/m) : Fd3c
7.CC.25VoltaiteK2Fe2+5Fe3+3Al(SO4)12 · 18H2OIso. m3m(4/m32/m) : Fd3c
7.CC.25MagnesiovoltaiteK2Mg5Fe3+3Al(SO4)12 · 18H2OIso. m3m(4/m32/m) : Fd3c
7.CC.25PertlikiteK2(Fe2+,Mg)2(Mg,Fe3+)4Fe3+2Al(SO4)12 · 18H2OTet. 4/mmm(4/m2/m2/m) : I41/acd
7.CC.25Ammoniomagnesiovoltaite(NH4)2Mg2+5Fe3+3Al(SO4)12 · 18H2OIso. m3m(4/m32/m) : Fd3c
7.CC.30KröhnkiteNa2Cu(SO4)2 · 2H2OMon. 2/m : P21/b
7.CC.35FerrinatriteNa3Fe(SO4)3 · 3H2OTrig. 3 : P3
7.CC.40GoldichiteKFe(SO4)2 · 4H2OMon. 2/m : P21/b
7.CC.45LöweiteNa12Mg7(SO4)13 · 15H2OTrig. 3 : R3
7.CC.50NickelblöditeNa2Ni(SO4)2 · 4H2OMon. 2/m : P21/b
7.CC.50BlöditeNa2Mg(SO4)2 · 4H2OMon. 2/m : P21/b
7.CC.50ChangoiteNa2Zn(SO4)2 · 4H2OMon. 2/m : P21/b
7.CC.55LeoniteK2Mg(SO4)2 · 4H2OMon. 2/m : B2/m
7.CC.55MereiteriteK2Fe(SO4)2 · 4H2OMon. 2/m : B2/m
7.CC.60NickelpicromeriteK2Ni(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.60Nickelboussingaultite(NH4)2Ni(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.60Katerinopoulosite(NH4)2Zn(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.60PicromeriteK2Mg(SO4)2 · 6H2OMon. 2/m : P2/b
7.CC.60CyanochroiteK2Cu(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.60Mohrite(NH4)2Fe(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.60Boussingaultite(NH4)2Mg(SO4)2 · 6H2OMon. 2/m : P21/b
7.CC.65PolyhaliteK2Ca2Mg(SO4)4 · 2H2OTric. 1
7.CC.70LeightoniteK2Ca2Cu(SO4)4 · 2H2OMon. 2/m : B2/b
7.CC.75AmarilliteNaFe(SO4)2 · 6H2OMon. 2/m : B2/b
7.CC.80KonyaiteNa2Mg(SO4)2 · 5H2OMon. 2/m : P21/b
7.CC.85WattevilleiteNa2Ca(SO4)2 · 4H2O (?)Orth.
7.CC.85XocolatliteCa2Mn4+2(Te6+O6)2 · H2OMon. 2/m : P2/m
7.CC.90Eckhardite(Ca,Pb)Cu2+Te6+O5(H2O)Mon. 2/m

Other InformationHide

Notes:
Soluble in H2O
Special Storage/
Display Requirements:
on exposure dehydrates to tamarugite
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 MendoziteHide

References for MendoziteHide

Reference List:

Localities for MendoziteHide

Showing 39 localities.

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.
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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.
Argentina (TL)
 
  • San Juan Province
    • Capital Department
Am Min 57:1081 (1972)
    • Iglesia Department
Angelelli et al. (1983)
Australia
 
  • Western Australia
    • Ravensthorpe Shire
      • Ravensthorpe
Simpson Mineral Collection of the ... +1 other reference
Canada
 
  • British Columbia
    • Kamloops Mining Division
      • Maggie claim group
Schmetzer et al. (1983)
Cape Verde
 
  • Sotavento Islands
    • Fogo Island
Silva et al. (2019)
Chile
 
  • Antofagasta
    • El Loa Province
      • Calama
        • Chuquicamata District
Cook (1978)
  • Tarapacá
    • Tamarugal Province
Peter G. Seroka collection
Costa Rica
 
  • Cartago Province
    • Oreamuno Canton
      • Irazú Volcano
Ulloa et al. (2018)
Germany
 
  • North Rhine-Westphalia
    • Arnsberg
      • Herne
        • Baukau
Weiß (1990)
      • Märkischer Kreis
        • Iserlohn
          • Letmathe
            • Helmke quarry nature reserve
Bender et al. (1994)
Greece
 
  • South Aegean
    • Milos
      • Milos Island
Shepard (1829)
Hungary
 
  • Heves County
    • Pétervására District
      • Recsk
Szakáll et al. (1997)
Szakáll et al. (1996)
Italy
 
  • Campania
    • Metropolitan City of Naples
      • Pozzuoli
70.1911encyclopedia.org (n.d.)
  • Sicily
    • Metropolitan City of Messina
      • Eolie Islands (Aeolian Islands)
        • Lipari
          • Vulcano Island
PANICHI U. (1924)
            • Porto Levante
              • Faraglioni di Levante
                • Faraglione Nico
P.Forti (1994)
Japan
 
  • Shimane Prefecture
Divers (1881)
New Zealand
 
  • Waikato Region
    • Taupo District
Johnstone (1979)
Johnstone (1979)
Nicaragua
 
  • León Department
    • La Paz Centro
      • Momotombo volcano
Hynek et al. (2013, March) +1 other reference
Norway
 
  • Innlandet
Selbekk et al. (2010)
    • Ringebu
      • Fåvang
Broch (1931)
Poland
 
  • Silesian Voivodeship
    • Wodzisław County
      • Radlin
Cu +2 other references
Senegal
 
  • Ziguinchor Region
Montoroi (1995)
Slovakia
 
  • Banská Bystrica Region
    • Žiar nad Hronom District
      • Kremnica
Ďuďa (1993)
USA
 
  • California
    • Amador County
      • Volcano Mining District
        • Volcano
Murdoch (1966)
    • Napa County
      • Yountville
Murdoch et al. (1966)
    • San Bernardino County
      • Hidden Springs
Murdoch et al. (1966)
  • Colorado
    • Eagle County
      • Gilman Mining District (Battle Mountain Mining District; Red Cliff Mining District)
Eckel et al. (1997)
  • Georgia
    • Rabun County
Cook (1978)
AmMin. 20:229
    • Callaway County
      • Fulton
Rocks & Min.
    • St. Louis County
Sherwood et al. (1998)
  • Nevada
    • Esmeralda County
Castor et al. (2004)
  • New Mexico
    • Guadalupe County
Northrop et al. (1996)
    • Torrance County
Northrop et al. (1996)
  • Virginia
    • Chesterfield County
Dietrich (1990)
  • Washington
    • Yakima County
      • Mount Adams
Cannon (1975)
Uzbekistan
 
  • Ferghana Region
    • Uzbekistan District
Uklonskiy et al. (1964) +1 other reference
 
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