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Muthmannite

A valid IMA mineral species - grandfathered
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09967060017271925283741.jpg
Muthmannite

Săcărâmb, Certeju de Sus, Hunedoara County, Romania
06298380017608249106379.jpg
Muthmannite

Săcărâmb, Certeju de Sus, Hunedoara County, Romania
09967060017271925283741.jpg
Muthmannite

Săcărâmb, Certeju de Sus, Hunedoara County, Romania
07993420017608034872250.jpg
Muthmannite

Săcărâmb, Certeju de Sus, Hunedoara County, Romania
09967060017271925283741.jpg
Muthmannite

Săcărâmb, Certeju de Sus, Hunedoara County, Romania
06298380017608249106379.jpg
Muthmannite

Săcărâmb, Certeju de Sus, Hunedoara County, Romania
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About MuthmanniteHide

08800790017271925324846.jpg
F. Wilhelm Muthmann
Formula:
AuAgTe2
Colour:
Brassy yellow to pale bronze
Lustre:
Metallic
Hardness:
2½
Specific Gravity:
11.04 (Calculated)
Crystal System:
Monoclinic
Name:
Named in honor of Friedrich Wilhelm Muthmann (8 February 1861, Elberfeld - 3 August 1913, Munich), German chemist and crystallographer, and professor at Technische Hochschule, Munich.
Originally described as (Ag,Au)Te, recently redefined as AuAgTe2 (Bindi & Cipriani, 2004).


Unique IdentifiersHide

Mindat ID:
2819
Long-form identifier:
mindat:1:1:2819:2

IMA Classification of MuthmanniteHide

Classification of MuthmanniteHide

Strunz-mindat (2026):
2.CB.85

2 : SULFIDES and SULFOSALTS (sulfides, selenides, tellurides; arsenides, antimonides, bismuthides; sulfarsenites, sulfantimonites, sulfbismuthites, etc.)
C : Metal Sulfides, M: S = 1: 1 (and similar)
B : With Zn, Fe, Cu, Ag, etc.
Dana 8th ed.:
2.8.26.

2 : SULFIDES
8 : AmXp, with m:p = 1:1
Hey's CIM Ref.:
3.3.8

3 : Sulphides, Selenides, Tellurides, Arsenides and Bismuthides (except the arsenides, antimonides and bismuthides of Cu, Ag and Au, which are included in Section 1)
3 : Sulphides etc. of Au

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

Physical Properties of MuthmanniteHide

Lustre:
Metallic
Transparency:
Opaque
Colour:
Brassy yellow to pale bronze
Comment:
pale gray on fresh fracture
Streak:
Black to gray-black
Hardness:
2½ on Mohs scale
Hardness:
VHN15=194 kg/mm2 - Vickers
Cleavage:
Perfect
in zone of elongation
Fracture:
Irregular/Uneven
Density:
11.04 g/cm3 (Calculated)

Optical Data of MuthmanniteHide

Anisotropism:
Very weak
Bireflectance:
very low
Reflectivity:
WavelengthR1 (%)
420nm42.3%
440nm41.3%
460nm40.4%
480nm39.7%
500nm39.2%
520nm38.7%
540nm38.4%
560nm38.2%
580nm38.1%
600nm38.0%
620nm38.0%
640nm38.0%
660nm38.1%
680nm38.2%
700nm38.4%


Graph shows reflectance levels at different wavelengths (in nm). Peak reflectance is 42.3%.
Colour in reflected light:
pale gray
Pleochroism:
Weak
Comments:
very low

Chemistry of MuthmanniteHide

Mindat Formula:
AuAgTe2
Element Weights:
Element% weight
Te45.569 %
Ag19.261 %

Calculated from ideal end-member formula.
Te
Ag
Elements listed:
Ag, Au, Te - search for minerals with similar chemistry
Common Impurities:
Pb,Sb,S

Crystallography of MuthmanniteHide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P2/m
Setting:
P2/m
Cell Parameters:
a = 5.124(2) Å, b = 4.419(1) Å, c = 7.437 Å
β = 89.96°
Ratio:
a:b:c = 1.16 : 1 : 1.683
Unit Cell V:
168.40 ų (Calculated from Unit Cell)
Z:
2
Comment:
some analogies to calaverite

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0003649MuthmanniteBindi L, Cipriani C (2004) Ordered distribution of Au and Ag in the crystal structure of muthmannite, AuAgTe2, a rare telluride from Sacarimb, Western Romania American Mineralogist 89 1505-150920040293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
5.124 Å(12)
3.346 Å(16)
3.052 Å(22)
3.051 Å(19)
2.562 Å(24)
2.488 Å(93)
2.487 Å(100)
2.210 Å(42)
1.8592 Å(22)
1.5931 Å(17)
Comments:
From calculated pattern. Similar to the data for calaverite.

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
High-? alteration and/or metamorphism
33 : Minerals deposited by hydrothermal metal-rich fluids (see also [#12])

Type Occurrence of MuthmanniteHide

Other Language Names for MuthmanniteHide

Related Minerals - Strunz-mindat GroupingHide

2.CB.RichardsiteZn2CuGaS4Tet. 42m : I42m
2.CB.OkruginiteCu2SnSe3Mon. m : Bb
2.CB.HanswilkeiteKFeS2Mon. 2/m : B2/b
2.CB.AuroselenideAuSeMon. 2/m : B2/m
2.CB.Ruizhongite(Ag2◻)Pb3Ge2S8Iso. 43m : I43d
2.CB.AgmantiniteAg2MnSnS4Orth.
2.CB.TolstykhiteAu3S4Te6Tric. 1 : P1
2.CB.GachingiteAu(Te1-xSex)Orth. mmm(2/m2/m2/m)
2.CB.05aHawleyiteCdSIso. 43m : F43m
2.CB.05'UM1998-15-S:CuFeZn'Cu2Fe3Zn5S10
2.CB.05aColoradoiteHgTeIso. 43m : F43m
2.CB.05aMetacinnabarHgSIso. 43m : F43m
2.CB.05aTiemanniteHgSeIso. 43m : F43m
2.CB.05aSphaleriteZnSIso. 43m : F43m
2.CB.05bSakuraiite(Cu,Zn,Fe)3(In,Sn)S4 Iso.
2.CB.05cPolhemusite(Zn,Hg)STet.
2.CB.05aRudashevskyite(Fe,Zn)SIso. 43m : F43m
2.CB.05aStilleiteZnSeIso. 43m : F43m
2.CB.05aIshiharaite(Cu,Ga,Fe,In,Zn)SIso. 43m : F43m
2.CB.07a'Unnamed (Cu-Mn-Sn Sulphide)'Cu2MnSnS4
2.CB.07aShenzhuangiteNiFeS2Tet. 42m : I42d
2.CB.10bTalnakhiteCu9(Fe,Ni)8S16Iso. 43m : I43m
2.CB.10bHaycockiteCu4Fe5S8Orth. 222
2.CB.10aLenaiteAgFeS2Tet. 42m : I42d
2.CB.10aGalliteCuGaS2Tet. 42m : I42d
2.CB.10aRoquesiteCuInS2Tet. 42m : I42d
2.CB.10aEskeborniteCuFeSe2Tet. 42m : P42c
2.CB.10a'UM1984-30-S:CuFeSn'Cu2Fe2Sn3S7
2.CB.10cOmariniiteCu8Fe2ZnGe2S12Orth. 222 : I222
2.CB.10aChalcopyriteCuFeS2Tet. 42m : I42d
2.CB.10a'Unnamed (Cu-Zn-In Sulphide)'CuZn2InS4
2.CB.10bMooihoekiteCu9Fe9S16Tet. 42m : P42m
2.CB.10aLaforêtiteAgInS2Tet. 42m : I42d
2.CB.10bPutoraniteCu1.1Fe1.2S2Iso. m3m(4/m32/m) : Pn3m
2.CB.15aVelikiteCu2HgSnS4Tet. 4 : I4
2.CB.15c'UM2006-11-S:CuFeGeZn'Cu8(Fe,Zn)3Ge2S12 (?)
2.CB.15aHocartiteAg2(Fe2+,Zn)SnS4Tet. 42m : I42m
2.CB.15aKësteriteCu2ZnSnS4Tet. 4 : I4
2.CB.15aPirquitasiteAg2ZnSnS4Tet. 4 : I4
2.CB.15aStanniteCu2FeSnS4Tet. 42m : I42m
2.CB.15cStannoiditeCu+6Cu2+2(Fe2+,Zn)3Sn2S12Orth. 222 : I222
2.CB.15bMohiteCu2SnS3Mon.
2.CB.15aČernýiteCu2CdSnS4Tet. 42m : I42m
2.CB.15aIdaiteCu5FeS6Hex.
2.CB.15aFerrokësteriteCu2FeSnS4Tet. 4 : I4
2.CB.15aKuramiteCu3SnS4Tet. 42m : I42m
2.CB.17a v'Arsenic-bearing Renierite'Cu11GeAsFe4S16
2.CB.20MawsoniteCu6Fe2SnS8Tet. 42m : P4m2
2.CB.20ChatkaliteCu6FeSn2S8Tet. 42m : P4m2
2.CB.30'Frieseite'Ag2Fe5S8 (?)
2.CB.30NekrasoviteCu26V2(Sn,As,Sb)6S32Iso. 43m : P43n
2.CB.30'Argyropyrite'near Ag2Fe7S11
2.CB.30MaikainiteCu20(Fe,Cu)6Mo2Ge6S32Iso. m3m(4/m32/m)
2.CB.30ColusiteCu13VAs3S16Iso. 43m : P43n
2.CB.30GermaniteCu13Fe2Ge2S16Iso. 43m : P43n
2.CB.30GermanocolusiteCu26V2(Ge,As)6S32Iso. 43m : P43m
2.CB.30StibiocolusiteCu13V(Sb,Sn,As)3S16Iso. 43m : P43m
2.CB.30Ovamboite Cu20(Fe,Cu,Zn)6W2Ge6S32Iso. 43m : P43n
2.CB.35aMorozeviczite(Pb,Fe)3Ge1-xS4Iso.
2.CB.35aRenierite(Cu+,Zn)11Fe4(Ge4+,As5+)2S16Tet. 42m : P42c
2.CB.35aHemusiteCu6SnMoS8Iso.
2.CB.35bCatamarcaiteCu6GeWS8Hex. 6mm : P63mc
2.CB.35aVincienniteCu+7Cu2+3Fe2+2Fe3+2Sn(As,Sb)S16Tet.
2.CB.35aKiddcreekiteCu6SnWS8Iso. 43m : F43m
2.CB.35aPolkovicite(Fe,Pb)3(Ge,Fe)1-xS4Iso.
2.CB.40LautiteCuAsSOrth. mmm(2/m2/m2/m) : Pnma
2.CB.42LingbaoiteAgTe3Trig. 3m : R3m
2.CB.45CadmoseliteCdSeHex. 6mm : P63mc
2.CB.45RambergiteMnSHex. 6mm : P63mc
2.CB.45Buseckite(Fe,Zn,Mn)SHex. 6mm : P63mc
2.CB.45MaletoyvayamiteAu3Se4Te6Tric. 1 : P1
2.CB.45GreenockiteCdSHex. 6mm : P63mc
2.CB.45Wurtzite(Zn,Fe)SHex. 6mm : P63mc
2.CB.47MurchisiteCr5S6Trig. 3m(32/m) : P31c
2.CB.50'Zincselenide'ZnSe
2.CB.50WassoniteTiSTrig. 3m(32/m) : R3m
2.CB.52'Dzhezkazganite'ReMoCu2PbS6 ?Trig. 3m : R3m
2.CB.55bIsocubaniteCuFe2S3Iso. m3m(4/m32/m) : Fm3m
2.CB.55aCubaniteCuFe2S3Orth. mmm(2/m2/m2/m)
2.CB.60RaguiniteTlFeS2Orth.
2.CB.60PicotpauliteTlFe2S3Orth. mmm(2/m2/m2/m) : Cmcm
2.CB.65ArgentopyriteAgFe2S3Mon. 2/m
2.CB.65SternbergiteAgFe2S3Orth. mmm(2/m2/m2/m)
2.CB.70SulvaniteCu3VS4Iso. 43m : P43m
2.CB.75VulcaniteCuTeOrth. mmm(2/m2/m2/m)
2.CB.80EmpressiteAgTeOrth. mmm(2/m2/m2/m)

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 MuthmanniteHide

References for MuthmanniteHide

Localities for MuthmanniteHide

Showing 19 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.
Brazil
 
  • Pará
    • Parauapebas
      • Alemão Cu deposit
Grainger et al. (2008)
Canada
 
  • Québec
    • Abitibi-Témiscamingue
      • Rouyn-Noranda TE
        • Horne Mine (Noranda Mine)
Krushnisky et al. (2023)
Chile
 
  • Atacama
    • Huasco Province
      • Alto del Carmen
Chouinard et al. (2005)
China
 
  • Gansu
    • Dingxi
      • Min Co.
Xinhui Liu et al. (2011) +1 other reference
  • Hebei
    • Zhangjiakou
      • Chongli District
        • Shuiquangou Complex
          • Dongping Au-Te ore field
Wang et al. (2019) +1 other reference
Ethiopia
 
  • Benishangul-Gumuz Region
Kabeta et al. (2024)
Finland
 
  • Lapland
    • Sodankylä
      • Viiankiaapa mire area
Fröhlich et al. (2017) +1 other reference
Greece
 
  • Central Macedonia
    • Chalkidiki
      • Aristotelis
        • Kassandra mining district
McFall et al. (2016)
Poland
 
  • Lower Silesian Voivodeship
    • Karkonosze County
      • Kowary
Kozłowski et al. (2022)
Romania
 
  • Alba County
Bindi et al. (2004)
  • Hunedoara County
    • Certeju de Sus
Transactions of the USSR Academy of Sc. et al. (1985) +2 other references
Russia
 
  • Belgorod Oblast
    • Kursk Magnetic Anomaly group
Chernyshov et al. (2009, November)
  • Kamchatka Krai
    • Koryak Okrug
      • Karaginsky District
Spiridonov et al. (2009, April)
  • Khabarovsk Krai
    • Nikolayevsky District
Azarian et al. (2021)
    • Okhotsky District
      • Svetloye epithermal district
Tamara Yu. Yakich * et al. (2024) +2 other references
  • Orenburg Oblast
    • Gaysky District
Vikent’ev et al. (2006) +3 other references
  • Tuva
    • Todzhinsky District
Kuzhuget et al. (2023) +1 other reference
Sierra Leone
 
  • Northern Province
    • Koinadugu District
Stenhouse et al. (2016)
USA
 
  • Nevada
    • Lyon County
      • Singatse Range
        • Yerington Mining District
Aird et al. (2021)
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