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Mohrite

A valid IMA mineral species
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About MohriteHide

03012500017271925338911.jpg
Karl Friedrich Mohr
Formula:
(NH4)2Fe(SO4)2 · 6H2O
Colour:
Pale green to colorless
Lustre:
Vitreous
Hardness:
2 - 2½
Specific Gravity:
1.800 - 1.862
Crystal System:
Monoclinic
Name:
Named in 1964 by Carlo Lorenzo Garavelli in honor of Karl Friedrich Mohr [November 4, 1806 Koblenz, Germany – September 28, 1879], after whom the synthetic compound was originally named. Mohr was initially a business chemist, and he made many contributions to apparatus design, such as improved burets. His improvements to methods of volumetric analysis were important in quantitative chemical analysis. His theoretical contributions were very significant including his 1837 promulgation of a succinct description of the Conservation of Energy. Mohr was the author of books on chemistry as well as geology. Late in life, he came out of early retirement and worked as professor of pharmacy at the University of Bonn.

Unique IdentifiersHide

Mindat ID:
2742
Long-form identifier:
mindat:1:1:2742:3

Similar NamesHide

MarriteA valid IMA mineral species - grandfatheredAgPbAsS3
MeieriteA valid IMA mineral speciesBa44Si66Al30O192Cl25(OH)33
MohiteA valid IMA mineral speciesCu2SnS3
MohsiteA synonym of Dessauite-(Y)
Mohsite (of Levy)A synonym of Ilmenite
MoiraiteA valid IMA mineral species - pending publicationPb12Sb8As8S36
MooreiteA valid IMA mineral species - grandfatheredMg92Mn2Zn4(SO4)2(OH)26 · 8H2O
MouriteA valid IMA mineral speciesUMo5O12(OH)10
MuiriteA valid IMA mineral speciesBa10(Ca2Mn2+Ti)[Si8O24]O2Cl10
MöhniteA valid IMA mineral species(NH4)K2Na(SO4)2

IMA Classification of MohriteHide

Approved
IMA Formula:
(N3-H4)2Fe2+(S6+O4)2·6H2O
Approval year:
1964

Classification of MohriteHide

7.CC.60

7 : SULFATES (selenates, tellurates, chromates, molybdates, wolframates)
C : Sulfates (selenates, etc.) without additional anions, with H2O
C : With medium-sized and large cations
29.3.7.1

29 : HYDRATED ACID AND NORMAL SULFATES
3 : A2B(XO4)2·xH2O
25.11.16

25 : Sulphates
11 : Sulphates of Fe and other metals

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

Physical Properties of MohriteHide

Vitreous
Transparency:
Transparent
Colour:
Pale green to colorless
Hardness:
2 - 2½ on Mohs scale
Cleavage:
Perfect
Perfect on {102}
Distinct on {010}
Density:
1.800 - 1.862 g/cm3 (Measured)    1.838(32) g/cm3 (Calculated)

Optical Data of MohriteHide

Type:
Biaxial (+)
RI values:
nα = 1.48 - 1.486 nγ = 1.486 - 1.497
2V:
Measured: 65° to 75°
Max. Birefringence:
δ = 0.006 - 0.011
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:
relatively strong

Chemistry of MohriteHide

Mindat Formula:
(NH4)2Fe(SO4)2 · 6H2O
Element Weights:
Element% weight
O57.121 %
S16.354 %
Fe14.241 %
N7.144 %
H5.141 %

Calculated from ideal end-member formula.

Crystallography of MohriteHide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P21/b
Setting:
P21/c
Cell Parameters:
a = 6.24(1) Å, b = 12.65(2) Å, c = 9.32(2) Å
β = 106.79°
Ratio:
a:b:c = 0.493 : 1 : 0.737
Unit Cell V:
704.32 ų (Calculated from Unit Cell)
Z:
2
Morphology:
Subhedral crystals, irregular lamellae
Comment:
Synthetic

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0010076MohriteFiggis B N, Kucharski E S, Reynolds P A, Tasset F (1989) The structure of (ND4)2Fe(SO4)2*6D2O at 4.3 K by neutron diffraction Acta Crystallographica C45 942-9441989synthetic0293
CIF Raw Data - click here to close

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 7: Great Oxidation Event<2.4
45a : [Sulfates, arsenates, selenates, antimonates]
45b : [Other oxidized fumarolic minerals]
Geological Setting:
Boriferous fumaroles and geysers.

Type Occurrence of MohriteHide

Synonyms of MohriteHide

Other Language Names for MohriteHide

Dutch:Mohriet
German:Mohrit
Simplified Chinese:六水铵铁矾
Spanish:Mohrita
Traditional Chinese:六水銨鐵礬

Relationship of Mohrite to other SpeciesHide

Other Members of Picromerite Group:
Boussingaultite(NH4)2Mg(SO4)2 · 6H2OMon. 2/m : P21/b
CyanochroiteK2Cu(SO4)2 · 6H2OMon. 2/m : P21/b
Katerinopoulosite(NH4)2Zn(SO4)2 · 6H2OMon. 2/m : P21/b
Nickelboussingaultite(NH4)2Ni(SO4)2 · 6H2OMon. 2/m : P21/b
NickelpicromeriteK2Ni(SO4)2 · 6H2OMon. 2/m : P21/b
PicromeriteK2Mg(SO4)2 · 6H2OMon. 2/m : P2/b
Forms a series with:

Common AssociatesHide

Associations Based on Photo Data:
4 photos of Mohrite associated with Tschermigite(NH4)Al(SO4)2 · 12H2O
2 photos of Mohrite associated with Mascagnite(NH4)2SO4
1 photo of Mohrite associated with PyriteFeS2

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.15MendoziteNaAl(SO4)2 · 11H2OMon. 2/m : B2/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.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 water
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 MohriteHide

References for MohriteHide

Localities for MohriteHide

Showing 22 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.
Canada
 
  • Québec
    • Montérégie
      • La Vallée-du-Richelieu RCM
        • Mont Saint-Hilaire
Horváth (2007)
  • Saskatchewan
Greengrass et al. (1999)
Czech Republic
 
  • Hradec Králové Region
    • Trutnov District
      • Radvanice
Jirásek (2001)
  • Karlovy Vary Region
    • Sokolov District
      • Horní Slavkov
Plášil et al. (2006)
      • Krásno
Sejkora et al. (2006)
  • Liberec Region
Scharm +7 other references
  • Moravian-Silesian Region
    • Ostrava-City District
      • Ostrava
Matýsek et al. (2022)
Germany
 
  • Baden-Württemberg
    • Freiburg Region
      • Ortenaukreis
        • Oberwolfach
Walenta (1992)
Hungary
 
  • Baranya County
    • Komló District
      • Komló
GEODA 2007/1
    • Pécs District
Szakáll et al. (2008)
Italy (TL)
 
  • Tuscany
    • Grosseto Province
      • Montieri
Garavelli (1964)
Kenya
 
  • Trans-Nzoia County
    • Mount Elgon
Bowell et al. (1996)
New Zealand
 
  • Waikato Region
    • Taupo District
Johnstone (1979)
Johnstone (1979)
Peru
 
  • Arequipa
    • Caylloma Province
      • Chivay District
Ciesielczuk et al. (2013)
Poland
 
  • Silesian Voivodeship
    • Rybnik
      • Niedobczyce
Kruszewski et al. (2020)
    • Wodzisław County
      • Radlin
Kruszewski (2012)
      • Rydułtowy
        • ROW Ruch Rydułtowy Mine
Kruszewski et al. (2020)
      • Wodzisław Śląski
Kruszewski et al. (2018)
Russia
 
  • Chelyabinsk Oblast
Cesnokov et al. (1998)
Switzerland
 
  • Valais
    • Goms
      • Binn
        • Fäld
Analyses by N. Meisser (Musée cantonal de géologie, Lausanne)
USA
 
  • Kentucky
    • Floyd County
Hower et al. (2013)
 
and/or  
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