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⇱ Arsenopyrite: Mineral information, data and localities.

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Arsenopyrite

A valid IMA mineral species - grandfathered
This page kindly sponsored by Mark Kucera

About ArsenopyriteHide

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Formula:
FeAsS
Colour:
Silver-white to steel-gray, may have a slight yellow appearance
Lustre:
Metallic, Sub-Metallic
Hardness:
5½ - 6
Specific Gravity:
6.07
Crystal System:
Monoclinic
Name:
Named in 1847 by Ernst Friedrich Glocker for its composition, a contraction of the antiquated term "arsenical pyrite." Arsenopyrite was known much before 1847 and arsenopyrite, as a name, may be taken as a simple translation of "arsenkies".
Arsenopyrite Group.

Arsenopyrite is closely related to alloclasite, but is not an exact analogue, because of different As-S and S-As ordering.

Arsenopyrite may contain up to about 9 wt% Co; with higher Co contents, glaucodot will appear as a separate phase (Gammon, 1966).

May be confused with the iron arsenide löllingite.




Unique IdentifiersHide

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Mindat ID:
305
Long-form identifier:
mindat:1:1:305:8

IMA Classification of ArsenopyriteHide

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Approved, 'Grandfathered' (first described prior to 1959)

Classification of ArsenopyriteHide

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2.EB.20

2 : SULFIDES and SULFOSALTS (sulfides, selenides, tellurides; arsenides, antimonides, bismuthides; sulfarsenites, sulfantimonites, sulfbismuthites, etc.)
E : Metal Sulfides, M: S <= 1:2
B : M:S = 1:2, with Fe, Co, Ni, PGE, etc.
Dana 7th ed.:
2.12.4.1
2.12.4.1

2 : SULFIDES
12 : AmBnXp, with (m+n):p = 1:2
3.9.12

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

Mineral SymbolsHide

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

Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.

SymbolSourceReference for Standard
ApyIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43
ApyKretz (1983)Kretz, R. (1983) Symbols of rock-forming minerals. American Mineralogist, 68, 277–279.
ApySiivolam & Schmid (2007)Siivolam, J. and Schmid, R. (2007) Recommendations by the IUGS Subcommission on the Systematics of Metamorphic Rocks: List of mineral abbreviations. Web-version 01.02.07. IUGS Commission on the Systematics in Petrology. download
ApyWhitney & Evans (2010)Whitney, D.L. and Evans, B.W. (2010) Abbreviations for names of rock-forming minerals. American Mineralogist, 95, 185–187 doi:10.2138/am.2010.3371
ApyThe Canadian Mineralogist (2019)The Canadian Mineralogist (2019) The Canadian Mineralogist list of symbols for rock- and ore-forming minerals (December 30, 2019). download

Physical Properties of ArsenopyriteHide

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Metallic, Sub-Metallic
Transparency:
Opaque
Colour:
Silver-white to steel-gray, may have a slight yellow appearance
Comment:
Tarnished material common, some iridescent
Streak:
Gray-black
Hardness:
5½ - 6 on Mohs scale
Hardness:
VHN100=1081 kg/mm2 - Vickers
Comment:
VHN on (001) section
Tenacity:
Brittle
Cleavage:
Distinct/Good
Distinct on {001}; {010} in traces
Fracture:
Irregular/Uneven
Density:
6.07(15) g/cm3 (Measured)    6.18 g/cm3 (Calculated)

Optical Data of ArsenopyriteHide

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Anisotropism:
Strong red-violet
Reflectivity:
WavelengthR1 (%)R2 (%)
400nm50.3% 51.8%
420nm50.3% 51.8%
440nm51.3% 51.8%
460nm50.6% 51.8%
480nm51.0% 51.9%
500nm51.4% 51.9%
520nm51.8% 51.9%
540nm52.2% 51.9%
560nm52.5% 51.9%
580nm53.0% 51.8%
600nm53.4% 51.6%
620nm53.6% 51.5%
640nm53.6% 51.3%
660nm53.6% 51.3%
680nm53.4% 51.2%
700nm53.2% 51.0%


Graph shows reflectance levels at different wavelengths (in nm). Peak reflectance is 53.6%.
R1 shown in black, R2 shown in
Colour in reflected light:
White with faint yellow tint
Pleochroism:
Weak
Comments:
White or bluish tint, faint reddish yellow

Chemistry of ArsenopyriteHide

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Mindat Formula:
FeAsS
Element Weights:
Element% weight
As46.012 %
Fe34.296 %
S19.692 %

Calculated from ideal end-member formula.
Common Impurities:
Ag,Au,Co,Sn,Ni,Sb,Bi,Cu,Pb

Crystallography of ArsenopyriteHide

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Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
P21/b
Setting:
P21/c
Cell Parameters:
a = 5.7612(8) Å, b = 5.6841(7) Å, c = 5.7674(8) Å
β = 111.721(8)°
Ratio:
a:b:c = 1.014 : 1 : 1.015
Unit Cell V:
175.46 ų
Z:
4
Morphology:
Flat tabular to blocky (sometimes pseudo-octahedral or rhombic) to prismatic.
Twinning:
Common on {100} and {001}. Contact or penetration on {101}, on {012} trillings or cruciform.
Comment:
Cell parameters from Bindi et al. (2012), using stoichiometric crystals. Pseudo-orthorhombic, face-centred cell: ~5.7, ~6.4, ~9.6 A.

Crystallographic forms of ArsenopyriteHide

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Crystal Atlas:
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Arsenopyrite no.5 - Goldschmidt (1913-1926)
Arsenopyrite no.12 - Goldschmidt (1913-1926)
Arsenopyrite no.14 - Goldschmidt (1913-1926)
Arsenopyrite no.62 - Goldschmidt (1913-1926)
Arsenopyrite no.64 - Goldschmidt (1913-1926)
Arsenopyrite no.113 - Goldschmidt (1913-1926)
3d models and HTML5 code kindly provided by www.smorf.nl.

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Crystal StructureHide

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Data courtesy of the American Mineralogist Crystal Structure Database. Click on an AMCSD ID to view structure
IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0019195ArsenopyriteBindi L, Moelo Y, Leone P, Suchaud M (2012) Stoichiometric arsenopyrite, FeAsS, from La Roche-Balue Quarry, Loire-Atlantique, France: Crystal structure and Mossbauer study The Canadian Mineralogist 50 471-4792012La Roche-Balue Quarry, Loire-Atlantique, France0293
0010967ArsenopyriteFuess H, Kratz T, Topel-Schadt J, Miehe G (1987) Crystal structure refinement and electron microscopy of arsenopyrite Zeitschrift fur Kristallographie 179 335-346👁 Image
1987Hakansboda, Sweden0293
0010966ArsenopyriteFuess H, Kratz T, Topel-Schadt J, Miehe G (1987) Crystal structure refinement and electron microscopy of arsenopyrite Zeitschrift fur Kristallographie 179 335-346👁 Image
1987Hakansboda, Sweden0293
0016964ArsenopyriteBuerger M (1936) The symmetry and crystal structure of the minerals of the arsenopyrite group Zeitschrift fur Kristallographie 95 83-113👁 Image
1936St Peter mine, Spindelmuhle, Bohemia0293
0000112ArsenopyriteMorimoto N, Clark L A (1961) Arsenopyrite crystal-chemical relations From Freiberg, Germany American Mineralogist 46 1448-1469👁 Image
19610293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

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Loading XRD data...
Data courtesy of RRUFF project at University of Arizona, used with permission.
Powder Diffraction Data:
d-spacingIntensity
3.658 Å(40)
2.866 Å(5)
2.838 Å(30)
2.796 Å(10)
2.677 Å(100)
2.662 Å(100)
2.557 Å(10)
2.440 Å(90)
2.418 Å(95)
2.412 Å(95)
2.204 Å(25)
2.095 Å(20)
2.017 Å(5)
1.961 Å(50)
1.943 Å(25)
1.824 Å(70)
1.814 Å(90)
1.787 Å(5)
1.759 Å(20)
1.750 Å(5)
1.703 Å(5)
1.631 Å(30)
1.608 Å(25)
1.594 Å(15)
1.589 Å(20)
1.543 Å(20)
1.537 Å(20)
1.390 Å(5)
1.343 Å(15)
Comments:
ICDD 14-218 (Freiberg, Germany)

Geological EnvironmentHide

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Paragenetic Mode(s):
Geological Setting:
High-temperature gold-quartz or tin hydrothermal veins, pegmatites, contact metamorphic rocks, gneisses, schists.

Synonyms of ArsenopyriteHide

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Other Language Names for ArsenopyriteHide

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Varieties of ArsenopyriteHide

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Argentiferous MispickelName for a silver-bearing arsenopyrite.
Needs reinvestigation because not confirmed in modern studies.
DanaiteA Co-bearing variety of arsenopyrite.
Originally described from Franconia, Grafton Co., New Hampshire, USA.

NB: Not to be confused with Danalite, a species in the helvine group.

Relationship of Arsenopyrite to other SpeciesHide

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Other Members of Arsenopyrite Group:
Glaucodot(Co0.50Fe0.50)AsSOrth. mm2 : Pmn21
GudmunditeFeSbSMon. 2/m : P21/b
Osarsite(Os,Ru)AsSMon.
Ruarsite(Ru,Os)AsSMon.

Common AssociatesHide

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Associations Based on Photo Data:
2,381 photos of Arsenopyrite associated with QuartzSiO2
884 photos of Arsenopyrite associated with PyriteFeS2
742 photos of Arsenopyrite associated with ChalcopyriteCuFeS2
723 photos of Arsenopyrite associated with SphaleriteZnS
634 photos of Arsenopyrite associated with MuscoviteKAl2(AlSi3O10)(OH)2
623 photos of Arsenopyrite associated with FluoriteCaF2
597 photos of Arsenopyrite associated with CalciteCaCO3
521 photos of Arsenopyrite associated with SideriteFeCO3
337 photos of Arsenopyrite associated with PyrrhotiteFe1-xS
335 photos of Arsenopyrite associated with GalenaPbS

Related Minerals - Strunz-mindat GroupingHide

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2.EB.SelenolauriteRuSe2Iso. m3(2/m3) : Pa3
2.EB.AndrieslombaarditeRhSbSIso. 23 : P213
2.EB.Iridarsenite(Ir,Ru)As2Mon. 2/m : P21/b
2.EB.Kanatzidisite(SbBiS3)2Te2Mon. 2/m : P21/m
2.EB.05aVaesiteNiS2Iso. m3(2/m3) : Pa3
2.EB.05aHaueriteMnS2Iso. m3(2/m3) : Pa3
2.EB.05aLauriteRuS2Iso. m3(2/m3) : Pa3
2.EB.05aGaotaiiteIr3Te8Iso. m3(2/m3) : Pa3
2.EB.05aPenroseite(Ni,Co,Cu)Se2Iso. m3(2/m3) : Pa3
2.EB.05aFukuchiliteCu3FeS8Iso. m3(2/m3) : Pa3
2.EB.05aVillamanínite(Cu,Ni,Co,Fe)S2Tric.
2.EB.05aErlichmaniteOsS2Iso. m3(2/m3) : Pa3
2.EB.05aSperrylitePtAs2Iso. m3(2/m3) : Pa3
2.EB.05aGeversitePtSb2Iso. m3(2/m3) : Pa3
2.EB.05aCattieriteCoS2Iso. m3(2/m3) : Pa3
2.EB.05aAurostibiteAuSb2Iso. m3(2/m3) : Pa3
2.EB.05aTrogtaliteCoSe2Iso. m3(2/m3) : Pa3
2.EB.05a v'Cayeuxite'
2.EB.05aKruťaiteCuSe2Iso. m3(2/m3) : Pa3
2.EB.05aPyriteFeS2Iso. m3(2/m3) : Pa3
2.EB.05aInsizwaitePtBi2Iso. m3(2/m3) : Pa3
2.EB.05bBambollaiteCu(Se,Te)2Tet.
2.EB.05aDzharkeniteFeSe2Iso. m3(2/m3) : Pa3
2.EB.10aMarcasiteFeS2Orth. mmm(2/m2/m2/m) : Pnnm
2.EB.10eParacostibiteCoSbSOrth. mmm(2/m2/m2/m) : Pbca
2.EB.10fOeniteCoSbAsOrth.
2.EB.10ePararammelsbergiteNiAs2Orth. mmm(2/m2/m2/m) : Pbca
2.EB.10aMattagamiteCoTe2Orth. mmm(2/m2/m2/m) : Pnnm
2.EB.10aFrohbergiteFeTe2Orth. mmm(2/m2/m2/m) : Pnnm
2.EB.10dCostibiteCoSbSOrth. mm2 : Pmn21
2.EB.10bAlloclasiteCo1-xFexAsSMon. 2 : P21
2.EB.10cGlaucodot(Co0.50Fe0.50)AsSOrth. mm2 : Pmn21
2.EB.10aPetříčekiteCuSe2Orth. mmm(2/m2/m2/m) : Pnnm
2.EB.10aKulleruditeNiSe2Orth. mmm(2/m2/m2/m) : Pnnm
2.EB.10aFerroseliteFeSe2Orth. mmm(2/m2/m2/m) : Pnnm
2.EB.15bSeinäjokiteFeSb2Orth.
2.EB.15aRammelsbergiteNiAs2Orth. mmm(2/m2/m2/m) : Pnnm
2.EB.15aClinosaffloriteCoAs2Mon. 2/m : P21/m
2.EB.15cPaxiteCuAs2Mon. 2/m : P21/b
2.EB.15aNisbiteNiSb2Orth. mmm(2/m2/m2/m) : Pnnm
2.EB.15aLöllingiteFeAs2Orth. mmm(2/m2/m2/m) : Pnnm
2.EB.15aSafflorite(Co,Ni,Fe)As2Orth. mmm(2/m2/m2/m) : Pnnm
2.EB.15aOmeiite(Os,Ru)As2Orth.
2.EB.15aAnduoite(Ru,Os)As2Orth.
2.EB.20Ruarsite(Ru,Os)AsSMon.
2.EB.20Osarsite(Os,Ru)AsSMon.
2.EB.20GudmunditeFeSbSMon. 2/m : P21/b
2.EB.25MayingiteIrBiTeIso. m3(2/m3) : Pa3
2.EB.25MaslovitePtBiTeIso. 23 : P213
2.EB.25ParagersdorffiteNi(As,S)2Iso. m3(2/m3) : Pa3
2.EB.25OrthogersdorffiteNiAsSOrth. mm2 : Pca21
2.EB.25SulfopadmaitePdBiSIso. 23 : P213
2.EB.25JolliffeiteNiAsSeIso. m3(2/m3) : Pa3
2.EB.25CobaltiteCoAsSOrth. mm2 : Pca21
2.EB.25GuixiangiteNiBiSIso. 23 : P213
2.EB.25TestibiopalladitePdSbTeIso.
2.EB.25 va'Antimony-bearing Gersdorffite'Ni(As,Sb)S
2.EB.25KalungaitePdAsSeIso. m3(2/m3) : Pa3
2.EB.25Hollingworthite(Rh,Pt,Pd)AsSIso. m3(2/m3) : Pa3
2.EB.25MicheneritePdBiTeIso. 23 : P213
2.EB.25GersdorffiteNiAsSIso. 23 : P213
2.EB.25MilotaitePdSbSeIso. 23 : P213
2.EB.25TolovkiteIrSbSIso.
2.EB.25'Platarsite'Pt(As,S)2Iso. m3(2/m3) : Pa3
2.EB.25WillyamiteCoSbS
2.EB.25ChangchengiteIrBiSIso. 23 : P213
2.EB.25KvačekiteNiSbSeIso. 23 : P213
2.EB.25KrutoviteNiAs2Iso. 23 : P213
2.EB.25PadmaitePdBiSeIso. 432
2.EB.25UllmanniteNiSbSIso. 23 : P213
2.EB.25Irarsite(Ir,Ru,Rh,Pt)AsSIso. m3(2/m3) : Pa3
2.EB.30UrvantsevitePd(Bi,Pb)2Tet. 4/mmm(4/m2/m2/m) : I4/mmm
2.EB.35RheniiteReS2Tric. 1 : P1

Fluorescence of ArsenopyriteHide

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Not fluorescent

Other InformationHide

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Notes:
Decomposed by nitric acid with separation of arsenous acid and sulphur.

In a closed tube, at first gives a red sublimate of arsenic sulfide, then a black lustrous sublimate of metallic arsenic. In an open tube, gives sulphurous fumes and a white sublimate of arsenous acid.
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Arsenopyrite in petrologyHide

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An essential component of rock names highlighted in red, an accessory component in rock names highlighted in green.

Internet Links for ArsenopyriteHide

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mindat.org URL:
https://www.mindat.org/min-305.html
Please feel free to link to this page.

References for ArsenopyriteHide

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Reference List:

Significant localities for ArsenopyriteHide

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Showing 26 significant localities out of 11,388 recorded on mindat.org.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the 👁 Image
symbol to view information about a locality. The 👁 Image
symbol next to localities in the list can be used to jump to that position on the map.

Locality ListHide

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👁 Image
- This locality has map coordinates listed. 👁 Image
- This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality. 👁 Image
- Good crystals or important locality for species. 👁 Image
- 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.
Bolivia
  • Cochabamba
    • Ayopaya Province
Collections of Alfredo Petrov and Dr. ...
Canada
  • British Columbia
    • Slocan Mining Division
      • Riondel
Grice et al. (1977) +1 other reference
  • Ontario
    • Hastings County
      • Marmora Township
Sabina (1964) +1 other reference
China
  • Hunan
    • Chenzhou
      • Yizhang Co.
        • Yaogangxian W-Sn ore field
Keqin Xu (1957) +8 other references
Czech Republic
  • Ústí nad Labem Region
    • Chomutov District
      • Vejprty
Roman Gramblicka collection
Ecuador
  • El Oro Province
    • Santa Rosa Canton
      • Birón
Collected by Alejandro Felix Gutierrez (2013)
France
  • Brittany
    • Côtes-d'Armor
      • Guingamp
        • Belle-Isle-en-Terre
          • Coat an Noz
Pierrot et al. (1975)
Ireland
  • Munster
    • Cork County
      • Sheeps Head Peninsula
Flannery (n.d.)
Italy
  • Tuscany
    • Lucca Province
      • Stazzema
        • Mulina
          • Calcaferro
Biagioni (2009)
Japan
  • Oita Prefecture
    • Bungo-Ono City
Sadanaga et al. (1974) +1 other reference
Kosovo
  • Mitrovica District
    • Mitrovica
      • Trepča complex
Féraud J. (1979) +4 other references
Norway
  • Vestfold
    • Larvik Commune
      • Tvedalen
        • Tuften
Nordrum (2007)
Peru
  • Ancash
    • Bolognesi Province
      • Huallanca District
        • Huanzala
Imai et al. (1985) +1 other reference
    • Recuay Province
      • Ticapampa District
- (1997)
  • Huancavelica
    • Angaraes Province
      • Ccochaccasa District
Crowley et al. (1997)
Portugal
335-354 +10 other references
Russia
  • Primorsky Krai
    • Dalnegorsk Urban District
      • Dalnegorsk
Dobovol'skaya et al. (1990) +3 other references
Spain
  • Asturias
    • Belmonte de Miranda
Mesa et al. (2002) +2 other references
  • Extremadura
    • Cáceres
      • Almoharín
Aguado González (1985) +3 other references
  • La Rioja
USA
  • Connecticut
    • Fairfield County
      • Monroe
Mike Polletta and Jeremy Zolan field ...
    • Litchfield County
      • Roxbury
        • Mine Hill
Schairer (1931) +2 other references
      • Woodbury
        • Orenaug Hills
Identified by Jeremy Zolan
    • New Haven County
      • Seymour
Moritz (n.d.)
  • Maine
    • Kennebec County
      • Winslow
  • New York
    • Putnam County
      • Town of Kent
        • Pine Pond
New York State Museum Bull. 223 et al. (July-August 1919)
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