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Natroalunite-2c

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07718120017271925106709.jpg
Natroalunite-2c

Okumanza Hot Spring, Kusatsu, Agatsuma District, Gunma Prefecture, Japan
05586170017271925138285.jpg
Natroalunite-2c, etc.

Cerros Pintados, Tamarugal Province, Tarapacá, Chile
02359720017271925248242.jpg
Natroalunite-2c

Okumanza Hot Spring, Kusatsu, Agatsuma District, Gunma Prefecture, Japan
07718120017271925106709.jpg
Natroalunite-2c

Okumanza Hot Spring, Kusatsu, Agatsuma District, Gunma Prefecture, Japan
05586170017271925138285.jpg
Natroalunite-2c, etc.

Cerros Pintados, Tamarugal Province, Tarapacá, Chile
02359720017271925248242.jpg
Natroalunite-2c

Okumanza Hot Spring, Kusatsu, Agatsuma District, Gunma Prefecture, Japan
08844110017271925275414.jpg
Natroalunite-2c

Okumanza Hot Spring, Kusatsu, Agatsuma District, Gunma Prefecture, Japan
05586170017271925138285.jpg
Natroalunite-2c, etc.

Cerros Pintados, Tamarugal Province, Tarapacá, Chile
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About Natroalunite-2cHide

Formula:
(Na,Ca0.5,K)Al3(SO4)2(OH)6
Hardness:
3 - 4
Specific Gravity:
2 (Calculated)
Crystal System:
Trigonal
Name:
Originally named minamiite for Dr. A. E. Minami (1899-1977), later renamed natroalunite-2c for the structural relation (doubled c-axis) to natroalunite.
Alunite Group.
Originally named minamiite; renamed natroalunite-2c.


Unique IdentifiersHide

Mindat ID:
2715
Long-form identifier:
mindat:1:1:2715:7

Similar NamesHide

NatroaluniteA valid IMA mineral species - grandfatheredNaAl3(SO4)2(OH)6

IMA Classification of Natroalunite-2cHide

IMA status notes:
Published without approval
Approval history:
Published without approval: 2010

Classification of Natroalunite-2cHide

Strunz-mindat (2026):
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
Dana 8th ed.:
30.2.4.5

30 : ANHYDROUS SULFATES CONTAINING HYDROXYL OR HALOGEN
2 : (AB)2(XO4)Zq
Hey's CIM Ref.:
25.6.19

25 : Sulphates
6 : Sulphates of Al and Tl

Physical Properties of Natroalunite-2cHide

Hardness:
3 - 4 on Mohs scale
Density:
2 g/cm3 (Calculated)

Chemistry of Natroalunite-2cHide

Mindat Formula:
(Na,Ca0.5,K)Al3(SO4)2(OH)6
Element Weights:
Element% weight
O56.265 %
Al20.333 %
S16.109 %
Na5.775 %
H1.519 %

Calculated from ideal end-member formula.
Elements listed:
Al, Ca, H, K, Na, O, S - search for minerals with similar chemistry

Crystallography of Natroalunite-2cHide

Crystal System:
Trigonal
Class (H-M):
3m(32/m) - Hexagonal Scalenohedral
Space Group:
R3m
Cell Parameters:
a = 6.98 Å, c = 33.49 Å
Ratio:
a:c = 1 : 4.798
Unit Cell V:
1,413.05 ų (Calculated from Unit Cell)

First Recorded Occurrence of Natroalunite-2cHide

Synonyms of Natroalunite-2cHide

Other Language Names for Natroalunite-2cHide

German:Minamiit
Spanish:Minamiita

Relationship of Natroalunite-2c to other SpeciesHide

Member of:
Alunite Group > Alunite Supergroup
Other Members of Alunite Group:
AluniteKAl3(SO4)2(OH)6Trig. 3m : R3m
Ammonioalunite(NH4)Al3(SO4)2(OH)6Trig.
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
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 Natroalunite-2c associated with JurbaniteAl(SO4)(OH) · 5H2O
1 photo of Natroalunite-2c associated with BotryogenMgFe3+(SO4)2(OH) · 7H2O

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.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.10Ammonioalunite(NH4)Al3(SO4)2(OH)6Trig.
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 Natroalunite-2cHide

References for Natroalunite-2cHide

Localities for Natroalunite-2cHide

Showing 9 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.
Bulgaria
 
  • Pazardzhik Province
    • Panagyurishte Municipality
      • Popintsi
Hikov (2004) +1 other reference
Chile
 
  • Coquimbo
    • Elqui Province
      • Vicuña
Deyell et al. (2005)
  • Tarapacá
    • Tamarugal Province
Peter G. Seroka collection
Costa Rica
 
  • Alajuela Province
    • Sarchí Canton
Rodríguez et al. (2017)
Iceland
 
  • Northeastern Region
    • Þingeyjarsveit
      • Skútustaðahreppur
        • Myvatn
          • Námaskarð Geothermal Area
Carson et al. (2023)
Japan (FRL)
 
  • Gunma Prefecture
    • Agatsuma District
      • Kusatsu
Amer.Min. (1982) +1 other reference
  • Kagoshima Prefecture
    • Ibusuki City
      • Iwato mine
Econ Geol (1989)
  • Tokyo Metropolis
    • Hachijō Subprefecture
      • Aogashima Island
PXRD by John Attard
Russia
 
  • Kamchatka Krai
    • Yelizovsky District
Okrugin (2004)
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