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Ammonioalunite

A valid IMA mineral species
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About AmmonioaluniteHide

Formula:
(NH4)Al3(SO4)2(OH)6
Colour:
Grayish white
Lustre:
Vitreous
Hardness:
2 - 3
Specific Gravity:
2.4
Crystal System:
Trigonal
Name:
The name is derived from "alunite" since it is a member of the Alunite Sub-group. The "Ammonio" prefix designates that it is the (NH4)-dominant member of the sub-group.
This page provides mineralogical data about Ammonioalunite.


Unique IdentifiersHide

Mindat ID:
203
Long-form identifier:
mindat:1:1:203:1

IMA Classification of AmmonioaluniteHide

Classification of AmmonioaluniteHide

7.BC.10

7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
B : Sulfates (selenates, etc.) with additional anions, without H2O
C : With medium-sized and large cations
30.2.4.6

30 : ANHYDROUS SULFATES CONTAINING HYDROXYL OR HALOGEN
2 : (AB)2(XO4)Zq
25.1.10

25 : Sulphates
1 : Sulphates of the alkali metals and ammonium

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

Physical Properties of AmmonioaluniteHide

Vitreous
Transparency:
Transparent, Translucent
Colour:
Grayish white
Comment:
colorless in thin section.
Streak:
White
Hardness:
2 - 3 on Mohs scale
Cleavage:
Perfect
perfect on {0001}(by analogy with the alunite group).
Density:
2.4 g/cm3 (Measured)    2.58 g/cm3 (Calculated)

Optical Data of AmmonioaluniteHide

Type:
Uniaxial (+)
RI values:
nω = 1.590(5) nε = 1.602(5)
Max. Birefringence:
δ = 0.012
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.

Surface Relief:
Moderate

Chemistry of AmmonioaluniteHide

Mindat Formula:
(NH4)Al3(SO4)2(OH)6
Element Weights:
Element% weight
O56.973 %
Al20.589 %
S16.312 %
N3.563 %
H2.564 %

Calculated from ideal end-member formula.

Crystallography of AmmonioaluniteHide

Crystal System:
Trigonal
Cell Parameters:
a = 7.01 Å, c = 17.88 Å
Ratio:
a:c = 1 : 2.551
Unit Cell V:
760.91 ų (Calculated from Unit Cell)
Z:
3
Morphology:
As rhombohedral crystals, to 20 μm, forming granular masses.
Comment:
Point Group: 3 2/m or 3m; Space Group: R3m or R3m. a

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
3.023 Å(100)
5.04 Å(93)
2.996 Å(50)
1.917 Å(32)
2.353 Å(31)
1.753 Å(21)
3.514 Å(19)

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 3b: Earth’s earliest hydrosphere>4.45
14 : Hot springs, geysers, and other subaerial geothermal minerals
Stage 10a: Neoproterozoic oxygenation/terrestrial biosphere<0.6
49 : Oxic cellular biomineralization (see also #44)<0.54
50 : Coal and/or oil shale minerals<0.36
Stage 10b: Anthropogenic minerals<10 Ka
54 : Coal and other mine fire minerals (see also #51 and #56)

Type Occurrence of AmmonioaluniteHide

General Appearance of Type Material:
As rhombohedral crystals, to 20 µm, forming granular masses.
Place of Conservation of Type Material:
National Museum of Natural History, Washington, D.C., USA, 145596.
Geological Setting of Type Material:
Formed in hot springs under very acid conditions, rich in ammonium and sulfate, poor in potassium, below 100 C.
Associated Minerals at Type Locality:

Synonyms of AmmonioaluniteHide

Other Language Names for AmmonioaluniteHide

Relationship of Ammonioalunite to other SpeciesHide

Other Members of Alunite Group:
AluniteKAl3(SO4)2(OH)6Trig. 3m : R3m
Ammoniojarosite(NH4)Fe3+3(SO4)2(OH)6Trig. 3m : R3m
ArgentojarositeAgFe3+3(SO4)2(OH)6Trig. 3m : R3m
Beaverite-(Cu)Pb(Fe3+2Cu)(SO4)2(OH)6Trig. 3m(32/m) : R3m
Beaverite-(Zn)Pb(Fe3+2Zn)(SO4)2(OH)6Trig. 3m(32/m) : R3m
DorallchariteTlFe3+3(SO4)2(OH)6Trig. 3m(32/m) : R3m
HuangiteCa0.5Al3(SO4)2(OH)6Trig. 3m(32/m) : R3m
Hydroniumjarosite(H3O)Fe3+3(SO4)2(OH)6Trig. 3m(32/m) : R3m
JarositeKFe3+3(SO4)2(OH)6Trig. 3m(32/m) : R3m
NatroaluniteNaAl3(SO4)2(OH)6Trig. 3m : R3m
'Natroalunite-2c'(Na,Ca0.5,K)Al3(SO4)2(OH)6Trig. 3m(32/m) : R3m
NatrojarositeNaFe3(SO4)2(OH)6Trig. 3m : R3m
OsarizawaitePb(Al2Cu2+)(SO4)2(OH)6Trig. 3m(32/m) : R3m
PlumbojarositePb0.5Fe3+3(SO4)2(OH)6Trig. 3m(32/m) : R3m
Schlossmacherite(H3O)Al3(SO4)2(OH)6Trig. 3m(32/m) : R3m
WalthieriteBa0.5Al3(SO4)2(OH)6Trig.

Common AssociatesHide

Associations Based on Photo Data:
2 photos of Ammonioalunite associated with Ammoniojarosite(NH4)Fe3+3(SO4)2(OH)6
1 photo of Ammonioalunite associated with Godovikovite(NH4)Al(SO4)2
1 photo of Ammonioalunite associated with Kremersite(NH4,K)2[Fe3+Cl5(H2O)]
1 photo of Ammonioalunite associated with Pyracmonite(NH4)3Fe(SO4)3
1 photo of Ammonioalunite associated with Tschermigite(NH4)Al(SO4)2 · 12H2O

Related Minerals - Strunz-mindat GroupingHide

7.BC.ViskontitePb5Cu2(SO4)3(SeO3)(OH)6Orth. mm2 : Pmn21
7.BC.ZincochenitePb4Zn(OH)6(SO4)2Tric. 1 : P1
7.BC.D'Ansite-(Mn)Na21Mn2+(SO4)10Cl3Iso. 43m : I43d
7.BC.D'Ansite-(Fe)Na21Fe2+(SO4)10Cl3Iso. 43m : I43d
7.BC.Acmonidesite(NH4,K,Pb)8NaFe2+4(SO4)5Cl8Orth. 222 : C2221
7.BC.Adranosite(NH4)4NaAl2(SO4)4Cl(OH)2Tet. 4/mmm(4/m2/m2/m) : I41/acd
7.BC.ChromviskontitePb5Cu2(CrO4)3(SeO3)(OH)6Orth. mm2 : Pmn21
7.BC.BackitePb2AlTeO6ClTrig. 32 : P312
7.BC.Adranosite-(Fe)(NH4)4NaFe3+2(SO4)4Cl(OH)2Tet. 4/mmm(4/m2/m2/m) : I41/acd
7.BC.AgaitePb3CuTeO5(OH)2(CO3) Orth. mm2 : Pca21
7.BC.WildcatiteCaFe3+Te6+O5(OH)Trig. 3m(32/m) : P31m
7.BC.HagstromitePb8Cu2+(Te6+O6)2(CO3)Cl4Orth. mmm(2/m2/m2/m) : Ibam
7.BC.05D'AnsiteNa21Mg(SO4)10Cl3Iso. 43m : I43m
7.BC.07'Apatelite'Fe3(SO4)2(OH)5 · 0.5H2O
7.BC.07'Unnamed (Ba-Fe Vanadate)'Ba, Fe, V, O, H
7.BC.10JarositeKFe3+3(SO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.10DorallchariteTlFe3+3(SO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.10ArgentojarositeAgFe3+3(SO4)2(OH)6Trig. 3m : R3m
7.BC.10NatroaluniteNaAl3(SO4)2(OH)6Trig. 3m : R3m
7.BC.10NatrojarositeNaFe3(SO4)2(OH)6Trig. 3m : R3m
7.BC.10Beaverite-(Cu)Pb(Fe3+2Cu)(SO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.10Beaverite-(Zn)Pb(Fe3+2Zn)(SO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.10WalthieriteBa0.5Al3(SO4)2(OH)6Trig.
7.BC.10HuangiteCa0.5Al3(SO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.10'Natroalunite-2c'(Na,Ca0.5,K)Al3(SO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.10AluniteKAl3(SO4)2(OH)6Trig. 3m : R3m
7.BC.10PlumbojarositePb0.5Fe3+3(SO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.10Karlseifertite Pb(Ga2Ge)(AsO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.10Hydroniumjarosite(H3O)Fe3+3(SO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.10Ammoniojarosite(NH4)Fe3+3(SO4)2(OH)6Trig. 3m : R3m
7.BC.10OsarizawaitePb(Al2Cu2+)(SO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.10Schlossmacherite(H3O)Al3(SO4)2(OH)6Trig. 3m(32/m) : R3m
7.BC.15Ye'elimiteCa4Al6(SO4)O12Iso. 432 : I4132
7.BC.20NabokoiteKCu7(SO4)5(Te4+O3)OClTet. 4/mmm(4/m2/m2/m) : P4/ncc
7.BC.20PuniniteNa2Cu3O(SO4)3Mon. 2/m : B2/b
7.BC.20AtlasoviteK(BiO)Cu6Fe3+(SO4)5O3ClTet. 4/mmm(4/m2/m2/m) : P4/ncc
7.BC.25ChlorothioniteK2Cu(SO4)Cl2Orth. mmm(2/m2/m2/m) : Pnma
7.BC.30EuchlorineKNaCu3(SO4)3OMon. 2/m
7.BC.30FedotoviteK2Cu3(SO4)3OMon. 2/m : B2/b
7.BC.35KamchatkiteKCu3(SO4)2OClOrth. mmm(2/m2/m2/m) : Pnma
7.BC.40PiypiteK4Cu4O2(SO4)4 · (Na,Cu)ClTet. 4 : I4
7.BC.45AlumoklyuchevskiteK3Cu3(Al,Fe3+)(SO4)4O2Tric. 1 : P1
7.BC.45BelousoviteKZn(SO4)ClMon. 2/m : P21/b
7.BC.45KlyuchevskiteK3Cu3(Fe3+,Al)(SO4)4O2Mon. 2
7.BC.47MülleritePb2Fe3+(Te6+O6)ClTrig. 32 : P3112
7.BC.50CaledonitePb5Cu2(SO4)3(CO3)(OH)6Orth. mm2 : Pmn21
7.BC.50ElasmochloiteNa3Cu6BiO4(SO4)5Mon. 2/m
7.BC.52Eleomelanite(K2Pb)Cu4O2(SO4)4Mon. 2/m
7.BC.55FalgariteK4(VO)3(SO4)5Mon. 2/m : B2/b
7.BC.55WherryitePb7Cu2(SO4)4(SiO4)2(OH)2Mon. 2/m : B2/m
7.BC.57KrasheninnikoviteKNa2CaMg(SO4)3FHex. 6/mmm(6/m2/m2/m) : P63/mcm
7.BC.60WulffiteK3NaCu4O2(SO4)4Orth. mm2
7.BC.60ParawulffiteK5Na3Cu8O4(SO4)8Mon. 2/m : P2/b
7.BC.60MammothitePb6Cu4AlSb5+O2(OH)16Cl4(SO4)2Mon. 2 : B2
7.BC.62ShuvaloviteK2(Ca2Na)(SO4)3FOrth. mmm(2/m2/m2/m) : Pnma
7.BC.65SaccoiteCa2Mn3+2F(OH)8 · 0.5(SO4)Tet. 4/mmm(4/m2/m2/m) : P4/ncc
7.BC.65LinaritePbCu(SO4)(OH)2Mon. 2/m : P21/m
7.BC.65Therasiaite(NH4)3KNa2Fe2+Fe3+(SO4)3Cl5Mon. m : Bb
7.BC.65FranksousaitePbCu(Se6+O4)(OH)2Mon. 2/m : P21/m
7.BC.65MunakataitePb2Cu2(Se4+O3)(SO4)(OH)4Mon. 2/m : P21/m
7.BC.65SchmiederitePb2Cu2(Se6+O4)(Se4+O3)(OH)4Mon. 2/m : P21/m
7.BC.70ChenitePb4Cu(SO4)2(OH)6Tric. 1 : P1
7.BC.75KrivovichevitePb3Al(OH)6(SO4)(OH)Trig. 3m : R3c
7.BC.80AnhydrokainiteKMg(SO4)Cl

Other InformationHide

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 AmmonioaluniteHide

References for AmmonioaluniteHide

Localities for AmmonioaluniteHide

Showing 15 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.
Czech Republic
 
  • Central Bohemian Region
Žáček et al. (1995)
Excalibur Mineral Corp. - Mineral News
Zacek et al. (2019)
  • Hradec Králové Region
    • Trutnov District
      • Radvanice
Jirásek (2001)
Germany
 
  • North Rhine-Westphalia
    • Cologne
      • Aachen
        • Alsdorf
Witzke et al. (2015)
  • Thuringia
    • Greiz District
      • Kauern
Witzke et al. (1998)
Hungary
 
  • Baranya County
    • Pécs District
Szabó et al. (2015)
Lebanon
 
  • South Governorate
    • Jezzine District
Kruszewski (2019)
Poland
 
  • Silesian Voivodeship
    • Rybnik
      • Chwałowice
Ciesielczuk et al. (2014)
    • Rybnik County
      • Gmina Czerwionka-Leszczyny
Parafiniuk et al. (2009)
    • Wodzisław County
      • Radlin
Kruszewski et al. (2020)
USA
 
  • California
    • Napa County
      • Knoxville Mining District
        • Knoxville
Journal of Volcanology & Geothermal ...
    • Sonoma County
      • West Mayacmas Mining District
Altaner et al. (1988) +1 other reference
  • Nevada
    • Elko County
Jour.Volcanology & Geothermal Res. ... +1 other reference
    • Washoe County
      • Nightingale Mining District
Castor et al. (2004)
 
and/or  
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