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Trogtalite

A valid IMA mineral species - grandfathered
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09773960017271927197014.jpg
Trogtalite, etc.

Trogtal Quarries, Harz, Goslar District, Lower Saxony, Germany
03872210017271927243218.jpg
Trogtalite, etc.

Musonoi Mine, Kolwezi, Mutshatsha, Lualaba, DR Congo
05607910017271927281342.jpg
Trogtalite, etc.

Sierra de Cacheuta, Cacheuta District, Luján de Cuyo department, Mendoza Province, Argentina
09773960017271927197014.jpg
Trogtalite, etc.

Trogtal Quarries, Harz, Goslar District, Lower Saxony, Germany
03872210017271927243218.jpg
Trogtalite, etc.

Musonoi Mine, Kolwezi, Mutshatsha, Lualaba, DR Congo
05607910017271927281342.jpg
Trogtalite, etc.

Sierra de Cacheuta, Cacheuta District, Luján de Cuyo department, Mendoza Province, Argentina
09773960017271927197014.jpg
Trogtalite, etc.

Trogtal Quarries, Harz, Goslar District, Lower Saxony, Germany
03872210017271927243218.jpg
Trogtalite, etc.

Musonoi Mine, Kolwezi, Mutshatsha, Lualaba, DR Congo
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About TrogtaliteHide

Formula:
CoSe2
Colour:
Rose-violet
Lustre:
Metallic
Hardness:
7
Specific Gravity:
7.09
Crystal System:
Isometric
Member of:
Pyrite Group
Name:
Named after its discovery locality, Trogtal quarry, near Lautenthal, Harz, Germany.
Krut'aite-Trogtalite Series.


Unique IdentifiersHide

Mindat ID:
4028
Long-form identifier:
mindat:1:1:4028:6

Similar NamesHide

TroctoliteA rock classification type

IMA Classification of TrogtaliteHide

IMA status:
Approved, 'Grandfathered' (first described prior to 1959)
IMA Formula:
Co2+(Se2)2-
First published:
1955
Type description reference:
Ramdohr, P., Schmitt, M. (1955) Vier neue natürliche Kobaltselenide vom Steinbruch Trogtal bei Laufenthal im Harz. Neues Jahrbuch für Mineralogie, Monatshefte: 1955: 133-142.

Classification of TrogtaliteHide

Strunz-mindat (2026):
2.EB.05a

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 8th ed.:
2.12.1.5

2 : SULFIDES
12 : AmBnXp, with (m+n):p = 1:2
Hey's CIM Ref.:
3.10.6

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

Mineral SymbolsHide

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

Lustre:
Metallic
Transparency:
Opaque
Colour:
Rose-violet
Hardness:
7 on Mohs scale
Density:
7.09 g/cm3 (Measured)    7.12 g/cm3 (Calculated)
Comment:
Measured on synthetic material

Optical Data of TrogtaliteHide

Reflectivity:
WavelengthR1 (%)
400nm42.5%
440nm41.9%
480nm41.0%
520nm41.1%
560nm42.0%
600nm43.3%
640nm44.5%
680nm45.6%
700nm45.8%


Graph shows reflectance levels at different wavelengths (in nm). Peak reflectance is 45.8%.

Chemistry of TrogtaliteHide

Mindat Formula:
CoSe2
Element Weights:
Element% weight
Se72.824 %
Co27.177 %

Calculated from ideal end-member formula.
Elements listed:
Co, Se - search for minerals with similar chemistry
Common Impurities:
Cu,Pd

Crystallography of TrogtaliteHide

Crystal System:
Isometric
Class (H-M):
m3(2/m3) - Diploidal
Space Group:
Pa3
Setting:
Pa3
Cell Parameters:
a = 5.87(4) Å
Unit Cell V:
202.26 ų (Calculated from Unit Cell)
Z:
2

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0011915TrogtaliteFuruseth S, Kjekshus A, Andresen A F (1969) On the magnetic properties of CoSe2, NiS2, and NiSe2 Acta Chemica Scandinavica 23 2325-23341969synthetic0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
2.64 Å(100)
2.419 Å(90)
1.788 Å(80)
2.95 Å(70)
1.585 Å(70)
1.644 Å(50)
1.295 Å(50)

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 TrogtaliteHide

Type Locality:
ⓘ Trogtal Quarries, Harz (Landkreis Goslar), Goslar District, Lower Saxony, Germany
General Appearance of Type Material:
Intergrown with clausthalite as irregular grains, to 1 mm.
Place of Conservation of Type Material:
The Natural History Museum, London, England, 1980,400; National Museum of Natural History, Washington, D.C., USA, 112811
Associated Minerals at Type Locality:
BornhardtiteClausthaliteFerroseliteHematiteNative Gold
Native Selenium
Reference:
Ramdohr, P., Schmitt, M. (1955) Vier neue natürliche Kobaltselenide vom Steinbruch Trogtal bei Laufenthal im Harz. Neues Jahrbuch für Mineralogie, Monatshefte: 1955: 133-142.

Other Language Names for TrogtaliteHide

German:Trogtalit
Simplified Chinese:硬硒钴矿
Spanish:Trogtalita
Traditional Chinese:硬硒鈷礦

Relationship of Trogtalite to other SpeciesHide

Member of:
Pyrite Group
Other Members of Pyrite Group:
AurostibiteAuSb2Iso. m3(2/m3) : Pa3
CattieriteCoS2Iso. m3(2/m3) : Pa3
DzharkeniteFeSe2Iso. m3(2/m3) : Pa3
ErlichmaniteOsS2Iso. m3(2/m3) : Pa3
FukuchiliteCu3FeS8Iso. m3(2/m3) : Pa3
GaotaiiteIr3Te8Iso. m3(2/m3) : Pa3
GeversitePtSb2Iso. m3(2/m3) : Pa3
HaueriteMnS2Iso. m3(2/m3) : Pa3
InsizwaitePtBi2Iso. m3(2/m3) : Pa3
KruťaiteCuSe2Iso. m3(2/m3) : Pa3
LauriteRuS2Iso. m3(2/m3) : Pa3
Penroseite(Ni,Co,Cu)Se2Iso. m3(2/m3) : Pa3
PyriteFeS2Iso. m3(2/m3) : Pa3
SperrylitePtAs2Iso. m3(2/m3) : Pa3
VaesiteNiS2Iso. m3(2/m3) : Pa3
Villamanínite(Cu,Ni,Co,Fe)S2Tric.
Forms a series with:
KruťaiteKrut'aite-Trogtalite Series

Common AssociatesHide

Associations Based on Photo Data:
6 photos of Trogtalite associated with Oosterboschite(Pd,Cu)7Se5
6 photos of Trogtalite associated with CuprosklodowskiteCu(UO2)2(SiO3OH)2 · 6H2O
6 photos of Trogtalite associated with QuartzSiO2
6 photos of Trogtalite associated with ClausthalitePbSe
5 photos of Trogtalite associated with CobaltomeniteCoSeO3 · 2H2O
3 photos of Trogtalite associated with TyrrelliteCu(Co,Ni)2Se4
3 photos of Trogtalite associated with ChalcopyriteCuFeS2
3 photos of Trogtalite associated with KruťaiteCuSe2
2 photos of Trogtalite associated with DolomiteCaMg(CO3)2
2 photos of Trogtalite associated with Penroseite(Ni,Co,Cu)Se2

Related Minerals - Strunz-mindat GroupingHide

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.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.15aOmeiiteOsAs2Orth.
2.EB.15aAnduoiteRuAs2Orth.
2.EB.20ArsenopyriteFeAsSMon. 2/m : P21/b
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

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 TrogtaliteHide

References for TrogtaliteHide

Reference List:
De Jong, W. F., Willems, H. W. V. (1928) Die Verbindungen FeSe2, CoSe2 und NiSe2. Zeitschrift für anorganische und allgemeine Chemie, 170 (1). 241-245 doi:10.1002/zaac.19281700132
Ramdohr, P., Schmitt, M. (1955) Vier neue natürliche Kobaltselenide vom Steinbruch Trogtal bei Laufenthal im Harz. Neues Jahrbuch für Mineralogie, Monatshefte: 1955: 133-142.
Bøhm, Frithjof, Grønvold, Fredrik, Haraldsen, Haakon, Prydz, Harald (1955) X-Ray and Magnetic Study of the System Cobalt Selenium. Acta Chemica Scandinavica, 9. 1510-1522 doi:10.3891/acta.chem.scand.09-1510
Ramdohr, P., Schmitt, M. (1955) Vier neue natürliche Kobaltselenide vom Steinbruch Trogtal bei Laufenthal im Harz. Neues Jahrbuch für Mineralogie, Monatshefte: 1955: 133-142.
Fleischer, M. (1956) New mineral names. American Mineralogist, 41 (1-2). 163-168
Nickel, E.H. (1970) The application of ligand-field concepts to an understanding of the structural stabilities and solid-solution limits of sulphides and related minerals. Chemical Geology, 5 (4) 233-241 doi:10.1016/0009-2541(70)90040-9
Johan, Zdenek, Picot, Paul, Pierrot, Roland, Verbeek, Théodore (1970) L'oosterboschite (Pd,Cu)7Se5, une nouvelle espèce minérale et la trogtalite cupro˗palladifère de Musonoï (Katanga) Bulletin de Minéralogie, 93 (4) 476-481 doi:10.3406/bulmi.1970.6496
Nowack, E.; Schwarzenbach, D.; Hahn, Th. (1991) Charge densities in CoS2 and NiS2 (pyrite structure). Acta Crystallographica Section B Structural Science, 47 (5). 650-659 doi:10.1107/s0108768191004871
(2005) Trogtalite. Handbook of Mineralogy. Mineralogical Society of America
Keutsch, F. N.; Forster, H.-J.; Stanley, C. J.; Rhede, D. (2009) The discreditation of hastite, the orthorhombic dimorph of CoSe2, and observations on trogtalite, cubic CoSe2, from the type locality. The Canadian Mineralogist, 47 (4). 969-976 doi:10.3749/canmin.47.4.969
Birkholz, Mario (2014) Modeling the Shape of Ions in Pyrite-Type Crystals. Crystals, 4 (3) 390-403 doi:10.3390/cryst4030390
Hazen, Robert M., Hystad, Grethe, Golden, Joshua J., Hummer, Daniel R., Liu, Chao, Downs, Robert T., Morrison, Shaunna M., Ralph, Jolyon, Grew, Edward S. (2017) Cobalt mineral ecology. American Mineralogist, 102 (1) 108-116 doi:10.2138/am-2017-5798
Hu, Xiao‐Wen; Ling, Ming‐Xing; Yang, Xiao‐Yong; Li, Qing‐Chun; Cao, Min‐Qiang (2025) Discovery of Trogtalite (CoSe2) in the Qianjiadian Sandstone‐Type Uranium Deposit in China. Resource Geology, 75 (1). e70002 doi:10.1111/rge.70002

Localities for TrogtaliteHide

Showing 12 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.
Hide all sections | Show all sections

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.
Argentina
 
  • La Rioja Province
    • General Lamadrid Department
      • Villa Castelli
        • Sierra de Cacho
Brodtkorb (2002)
Paar (1996)
  • Mendoza Province
    • Luján de Cuyo department
      • Cacheuta District
pers. comm. Frank Keutsch (ID: SEM/EDS refl. light) +1 other reference
          • Cerro de Cacheuta
Zappettini et al. (2014) +1 other reference
Bolivia
 
  • Potosí
    • Antonio Quijarro Province
      • Porco Municipality
Schnorrer-Köhler et al. (1990) +2 other references
China
 
  • Inner Mongolia
    • Tongliao City (Tongliao Prefecture)
      • Horqin Left Middle Banner
        • Qianjiadian ore field
Hu et al. (2024) +1 other reference
Czech Republic
 
  • South Bohemian Region
    • Písek District
      • Kovářov
        • Předbořice
Bindi et al. (2016)
DR Congo
 
  • Haut-Katanga
    • Kambove Territory
      • Shinkolobwe
Gauthier et al. (1989)
  • Lualaba
    • Mutshatsha
      • Kolwezi
Deliens (1996) +3 other references
Germany (TL)
 
  • Lower Saxony
    • Goslar District
      • Harz (Landkreis Goslar)
Ramdohr et al. (1955) +3 other references
  • Saxony-Anhalt
    • Harz
      • Ballenstedt
        • Rieder
Heider et al. (2012)
    • Mansfeld-Südharz
      • Mansfeld
Tischendorf (1969) +1 other reference
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