Log InRegister
Quick Links : The Mindat ManualThe Rock H. Currier Digital LibraryMindat Newsletter [Free Download]
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsThe Rock H. Currier Digital LibraryGeologic Time
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsClubs & OrganizationsMineral Shows & EventsThe Mindat DirectoryDevice SettingsThe Mineral QuizTime Machine
Photo SearchPhoto GalleriesSearch by ColorNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryPhotography

Kieftite

A valid IMA mineral species
This page is currently not sponsored. Click here to sponsor this page.
08257130017271924208657.jpg
Kees Kieft
Formula:
CoSb3
Lustre:
Metallic
Hardness:
5 - 5½
Specific Gravity:
7.2
Crystal System:
Isometric
Name:
Named by R.T.M. Dobbe, W. Lustenhouwer, and M.A. Zakrzewski in 1994 in honor of Cornelis (‘Kees’) Kieft (Limmen, 29 September 1924 ‒ Heemstede, 6 February 1995), Dutch geologist and mineralogist, for his contributions to ore mineralogy.

This page provides mineralogical data about Kieftite.


Hide all sections | Show all sections

Unique IdentifiersHide

Mindat ID:
2203
Long-form identifier:
mindat:1:1:2203:9

IMA Classification of KieftiteHide

Classification of KieftiteHide

Strunz-mindat (2025):
2.EC.05

2 : SULFIDES and SULFOSALTS (sulfides, selenides, tellurides; arsenides, antimonides, bismuthides; sulfarsenites, sulfantimonites, sulfbismuthites, etc.)
E : Metal Sulfides, M: S <= 1:2
C : M:S = 1:>2
Dana 8th ed.:
2.12.17.3

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

Mineral SymbolsHide

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

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

Physical Properties of KieftiteHide

Lustre:
Metallic
Transparency:
Opaque
Streak:
Gray
Hardness:
5 - 5½ on Mohs scale
Hardness:
VHN100=420 - 514 kg/mm2 - Vickers
Tenacity:
Brittle
Density:
7.2 g/cm3 (Measured)    7.63 g/cm3 (Calculated)
Comment:
D(calc.) = 7.63 (for CoSb3).

Optical Data of KieftiteHide

Reflectivity:
WavelengthR1 (%)
470nm59.0%
546nm58.7%
589nm58.7%
650nm58.7%


Graph shows reflectance levels at different wavelengths (in nm). Peak reflectance is 59.0%.
Colour in reflected light:
Tin white
Internal Reflections:
None observed

Chemistry of KieftiteHide

Mindat Formula:
CoSb3
Element Weights:
Element% weight
Sb86.108 %
Co13.892 %

Calculated from ideal end-member formula.
Elements listed:
Co, Sb - search for minerals with similar chemistry
Common Impurities:
Ni,Fe,Cu,Cl

Crystallography of KieftiteHide

Crystal System:
Isometric
Class (H-M):
m3 (2/m 3) - Diploidal
Space Group:
Im3
Setting:
Im3
Cell Parameters:
a = 9.0411(3) Å
Unit Cell V:
739.03 ų (Calculated from Unit Cell)
Z:
8
Morphology:
Euhedral to subhedral crystals. Equant, showing {100}, {110}, {111}.

Crystal StructureHide

Load
Unit Cell | Unit Cell Packed
2x2x2 | 3x3x3 | 4x4x4
Show
Big Balls | Small Balls | Just Balls | Spacefill
Polyhedra Off | Si Polyhedra | All Polyhedra
Remove metal-metal sticks
Display Options
Black Background | White Background
Perspective On | Perspective Off
2D | Stereo | Red-Blue | Red-Cyan
View
CIF File    Best | x | y | z | a | b | c
Rotation
Stop | Start
Labels
Console Off | On | Grey | Yellow
IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0005362KieftiteDobbe R T M, Lustenhouwer W J, Zakrzewski M A, Goubitz K, Fraanje J, Schenk H (1994) Kieftite, CoSb3, a new member of the skutterudite group from Tunaberg, Sweden The Canadian Mineralogist 32 179-1831994Tunaberg, Sweden0293
0017609KieftiteKjekshus A, Rakke T (1974) Compounds with the skutterudite type crystal structure. III. Structural data for arsenides and antimonides, Acta Chemica Scandinavica A28 99-1031974synthetic0293
0017605KieftiteHe T, Chen J, Rosenfeld H D, Subramanian M A (2006) Thermoelectric properties of indium-filled skutterudites Chemistry of Materials 18 759-7622006synthetic0293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
2.86 Å(100)
2.02 Å(80)
0.933 Å(80)
1.331 Å(70)
2.42 Å(60)
1.77 Å(60)
1.55 Å(60)

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 KieftiteHide

Type Locality:
ⓘ Tunaberg Cu-Co Ore Field, Tunaberg, Nyköping, Södermanland County, Sweden
General Appearance of Type Material:
Tin-white, subhedral to euhedral crystals, up to 400 µm, in chalcopyrite.
Place of Conservation of Type Material:
Institute of Earth Sciences, Free University of Amsterdam, Amsterdam, The Netherlands.
Geological Setting of Type Material:
Cu-Co-sulfide skarn ore.
Associated Minerals at Type Locality:
Native BismuthBorniteChalcopyriteDyscrasiteGalena
GudmunditeNative SilverTetrahedrite Subgroup
Reference:
Dobbe, R. T. M., Lustenhouwer, W., Zakrzewski, M. A. (1994) Kieftite, CoSb3, a new member of the Skutterudite group from Tunaberg, Sweden. The Canadian Mineralogist, 32 (1) 179-183

Synonyms of KieftiteHide

Other Language Names for KieftiteHide

Dutch:Kieftiet
German:Kieftit
Russian:Кифтит
Spanish:Kieftita

Relationship of Kieftite to other SpeciesHide

Member of:
Skutterudite Subgroup > Non-stoichiometric Perovskites Group > Perovskite Supergroup
Other Members of Skutterudite Subgroup:
FerroskutteruditeFeAs3Iso. m3m (4/m 3 2/m) : Im3m
NickelskutteruditeNiAs3Iso. m3 (2/m 3) : Im3
SkutteruditeCoAs3Iso. m3 (2/m 3) : Im3

Related Minerals - Strunz-mindat GroupingHide

2.EC.05NickelskutteruditeNiAs3Iso. m3 (2/m 3) : Im3
2.EC.05SkutteruditeCoAs3Iso. m3 (2/m 3) : Im3
2.EC.05FerroskutteruditeFeAs3Iso. m3m (4/m 3 2/m) : Im3m
2.EC.10PatróniteVS4Mon. 2/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 KieftiteHide

References for KieftiteHide

Reference List:
Kjekshus, Arne, Rakke, Trond, Rundqvist, Stig, Østvold, Terje, Bjørseth, Alf, Powell, D. L. (1974) Compounds with the Skutterudite Type Crystal Structure. III. Structural Data for Arsenides and Antimonides. Acta Chemica Scandinavica, 28. 99-103 doi:10.3891/acta.chem.scand.28a-0099
Dobbe, R. T. M., Lustenhouwer, W., Zakrzewski, M. A. (1994) Kieftite, CoSb3, a new member of the Skutterudite group from Tunaberg, Sweden. The Canadian Mineralogist, 32 (1) 179-183
Zakrzewski, M. (1994) Kieftiet, een nieuw Nederlands mineraal. Gea: 27(4):140-143.(in Dutch)
Dobbe, R. T. M., Lustenhouwer, W., Zakrzewski, M. A. (1994) Kieftite, CoSb3, a new member of the Skutterudite group from Tunaberg, Sweden. The Canadian Mineralogist, 32 (1) 179-183
Jambor, J.L., Roberts, A.C. (1995) New mineral names. American Mineralogist: 80: 184-188.
Nolas, G. S., Slack, G. A., Caillat, T., Meisner, G. P. (1996) Raman scattering study of antimony‐based skutterudites. Journal of Applied Physics, 79 (5). 2622-2626 doi:10.1063/1.361132
Mandarino, Joseph A. (1997) New Minerals 1990-1994. The Mineralogical Record Inc., Tuscon, Arizona. 220pp.
Anno, H., Matsubara, K., Caillat, T., Fleurial, J.P. (2000) Valence-band structure of the skutterudite compounds CoAs3, CoSb3, and RhSb3 studied by X-ray photoelectron spectroscopy. Physical Review B: 62: 10737-10743.
(2005) Kieftite. Handbook of Mineralogy. Mineralogical Society of America
Okamoto, H. (2005) Co-Sb (Cobalt-Antimony) Journal of Phase Equilibria and Diffusion, 26 (2) 198 doi:10.1007/s11669-005-0156-7
Peng, J., Yang, J., Bao, S., Chen, Y., Zhang, T. (2006) Study on Raman spectra of CoSb3-based skutterudite compounds. Rare Metal Materials and Engineering: 35: 272-275.

Localities for KieftiteHide

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.

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.
Morocco
 
  • Drâa-Tafilalet Region
    • Zagora Province
      • Agdz Cercle
        • Tansifte Caïdat
Praszkier (2010)
Romania
 
  • Maramureș County
    • Târgu Lăpuș
HÎRTOPANU et al. (2025)
Sweden
 
  • Örebro County
    • Askersund
      • Zinkgruvan
Andersen (2009)
          • Knalla Mine
Andersen (2009)
  • Södermanland County
    • Nyköping
      • Tunaberg
Dobbe et al. (1994)
Quick NavTopUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography Crystal StructureX-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesRelationshipsStrunz-MindatOther InformationInternet Links References Localities Locality List
 
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2025, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters. Founded in 2000 by Jolyon Ralph.
To cite: Ralph, J., Von Bargen, D., Martynov, P., Zhang, J., Que, X., Prabhu, A., Morrison, S. M., Li, W., Chen, W., & Ma, X. (2025). Mindat.org: The open access mineralogy database to accelerate data-intensive geoscience research. American Mineralogist, 110(6), 833–844. doi:10.2138/am-2024-9486.
Privacy Policy - Terms & Conditions - Contact Us / DMCA issues - Report a bug/vulnerability Current server date and time: December 4, 2025 06:37:45 Page updated: November 20, 2025 20:06:07
Go to top of page