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Sederholmite

A valid IMA mineral species
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08989460017401732995103.jpg
Jakob Johannes Sederholm
Formula:
NiSe
Previously beta- NiSe
Colour:
Brass-yellow to orange-yellow
Lustre:
Metallic
Hardness:
2½ - 3
Specific Gravity:
7.11 (Calculated)
Crystal System:
Hexagonal
Member of:
Nickeline Group
Name:
Named in 1964 by Yrjö Vuorelainen after Jakob Johannes Sederholm [July 20, 1863 Helsinki, Finland - June 26, 1934], Director of the Geological Survey of Finland.
Dimorph of:
Mäkinenite
Isostructural with:
Nickeline
Metallic brass-yellow grains.


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Unique IdentifiersHide

Mindat ID:
3601
Long-form identifier:
mindat:1:1:3601:2

IMA Classification of SederholmiteHide

Classification of SederholmiteHide

Strunz-mindat (2026):
2.CC.05

2 : SULFIDES and SULFOSALTS (sulfides, selenides, tellurides; arsenides, antimonides, bismuthides; sulfarsenites, sulfantimonites, sulfbismuthites, etc.)
C : Metal Sulfides, M: S = 1: 1 (and similar)
C : With Ni, Fe, Co, PGE, etc.
Dana 8th ed.:
2.8.11.3

2 : SULFIDES
8 : AmXp, with m:p = 1:1
Hey's CIM Ref.:
3.11.15

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

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

Physical Properties of SederholmiteHide

Lustre:
Metallic
Transparency:
Opaque
Colour:
Brass-yellow to orange-yellow
Hardness:
2½ - 3 on Mohs scale
Tenacity:
Brittle
Cleavage:
None Observed
Fracture:
Irregular/Uneven, Sub-Conchoidal
Density:
7.11 g/cm3 (Calculated)

Chemistry of SederholmiteHide

Mindat Formula:
NiSe

Previously beta- NiSe
Element Weights:
Element% weight
Se57.362 %
Ni42.639 %

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

Crystallography of SederholmiteHide

Crystal System:
Hexagonal
Class (H-M):
6/mmm(6/m2/m2/m) - Dihexagonal Dipyramidal
Space Group:
P63/mmc
Cell Parameters:
a = 3.624 Å, c = 5.288 Å
Ratio:
a:c = 1 : 1.459
Unit Cell V:
60.14 ų (Calculated from Unit Cell)
Z:
2
Morphology:
Microscopic grains
Comment:
Synthetic material (Unoki et al., 2021) has: a = 3.66147 (10), c = 5.35766 (16) Å.

Crystal StructureHide

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IDSpeciesReferenceLinkYearLocalityPressure (GPa)Temp (K)
0011907SederholmiteRost E, Vestersjo E (1968) On the system Ni-Se-Te Acta Chemica Scandinavica 22 2118-21341968synthetic0293
0011906SederholmiteRost E, Vestersjo E (1968) On the system Ni-Se-Te Acta Chemica Scandinavica 22 2118-21341968synthetic0293
0011905SederholmiteRost E, Vestersjo E (1968) On the system Ni-Se-Te Acta Chemica Scandinavica 22 2118-21341968synthetic0293
0011904SederholmiteRost E, Vestersjo E (1968) On the system Ni-Se-Te Acta Chemica Scandinavica 22 2118-21341968synthetic0293
0011582SederholmiteWyckoff R W G (1963) Second edition. Interscience Publishers, New York, New York Crystal Structures 1 85-23719630293
0018201SederholmiteAlsen N (1925) Roentgenographische Untersuchungen der Kristallstrukturen von Magnetkies, Breithauptit, Pentlandit, Millerit und verwandten Verbindungen _cod_database_code 1011367 Geologiska Foreningens i Stockholm Forhandlingar 47 19-7319250293
CIF Raw Data - click here to close

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
2.70 Å(100)
2.02 Å(80)
1.81 Å(60)
1.54 Å(40)
1.50 Å(40)
1.35 Å(30)
1.16 Å(30)
1.08 Å(30)
Comments:
18-0888

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 SederholmiteHide

Type Locality:
ⓘ Kitka River Valley, Kuusamo, North Ostrobothnia, Finland
General Appearance of Type Material:
In penroseite clusters of a few millimeters in diameter
Geological Setting of Type Material:
In calcite veins containing nickel selenides, in sills of albitite diabase in schist, associated with low-grade uranium mineralization
Associated Minerals at Type Locality:
PenroseiteWilkmanite
Reference:
Vuorelainen, Y., Huhma, A., Häkli, A. (1964) Sederholmite, wilkmanite, kullerudite, mäkinenite, and trüstedtite, five new nickel selenide minerals. Comptes Rendus de la Société Géologique de Finlande, 36. 113-125

Other Language Names for SederholmiteHide

Relationship of Sederholmite to other SpeciesHide

Member of:
Nickeline Group
Other Members of Nickeline Group:
AchávaliteFeSeHex. 6/mmm(6/m2/m2/m) : P63/mmc
BreithauptiteNiSbHex. 6/mmm(6/m2/m2/m) : P63/mmc
DriekopitePtBiHex. 6/mmm(6/m2/m2/m) : P63/mmc
FrebolditeCoSeHex. 6/mmm(6/m2/m2/m) : P63/mmc
KotulskitePd(Te,Bi)2-x (x ≈ 0.4)Hex.
LangisiteCoAsHex. 6 : P63
NickelineNiAsHex. 6/mmm(6/m2/m2/m) : P63/mcm
SobolevskitePdBiHex.
StumpflitePtSbHex. 6/mmm(6/m2/m2/m) : P63/mmc
SudburyitePdSbHex. 6/mmm(6/m2/m2/m) : P63/mmc
VavříniteNi2SbTe2Hex. 6/mmm(6/m2/m2/m) : P63/mmc
ZlatogoriteNiCuSb2Trig. 3m(32/m) : P31m

Related Minerals - Strunz-mindat GroupingHide

2.CC.EliopoulositeV7S8Trig. 32 : P3221
2.CC.TilkerodeitePd2HgSe3Trig. 3m(32/m) : P3m1
2.CC.'UM2007-26-S:CuFeIrNiPtRh'(Ir,Cu,Ni,Pt,Rh,Fe)9S11
2.CC.Proxitwelvefoldite Pd3Ni4Te8Tet. 4/mmm(4/m2/m2/m) : P42/mnm
2.CC.FerrotorryweiseriteRh5Fe10S16Trig. 3m(32/m) : R3m
2.CC.TamuraiteIr5Fe10S16Trig. 3m(32/m) : R3m
2.CC.Crowningshieldite(Ni0.9Fe0.1)SHex. 6/mmm(6/m2/m2/m) : P63/mmc
2.CC.KuvaeviteIr5Ni10S16Trig. 3m(32/m) : R3m
2.CC.TorryweiseriteRh5Ni10S16Trig. 3m(32/m) : R3m
2.CC.05AchávaliteFeSeHex. 6/mmm(6/m2/m2/m) : P63/mmc
2.CC.05LangisiteCoAsHex. 6 : P63
2.CC.05FrebolditeCoSeHex. 6/mmm(6/m2/m2/m) : P63/mmc
2.CC.05NickelineNiAsHex. 6/mmm(6/m2/m2/m) : P63/mcm
2.CC.05SobolevskitePdBiHex.
2.CC.05JaipuriteCoSHex.
2.CC.05KotulskitePd(Te,Bi)2-x (x ≈ 0.4)Hex.
2.CC.05ZlatogoriteNiCuSb2Trig. 3m(32/m) : P31m
2.CC.05StumpflitePtSbHex. 6/mmm(6/m2/m2/m) : P63/mmc
2.CC.05SudburyitePdSbHex. 6/mmm(6/m2/m2/m) : P63/mmc
2.CC.05BreithauptiteNiSbHex. 6/mmm(6/m2/m2/m) : P63/mmc
2.CC.10PyrrhotiteFe1-xSMon.
2.CC.10Smythite(Fe,Ni)3+xS4 (x=0-0.3)Trig. 3m(32/m) : R3m
2.CC.10TroiliteFeSHex. 6/mmm(6/m2/m2/m) : P63/mmc
2.CC.15Ruthenarsenite(Ru,Ni)AsOrth. mmm(2/m2/m2/m) : Pnma
2.CC.15Westerveldite(Fe,Ni,Co)AsOrth. mmm(2/m2/m2/m)
2.CC.15ModderiteCoAsOrth. mmm(2/m2/m2/m)
2.CC.15MinakawaiteRhSbOrth. mmm(2/m2/m2/m) : Pnma
2.CC.15CherepanoviteRhAsOrth. mmm(2/m2/m2/m) : Pnma
2.CC.20'UM1990-38-S:CuFeIrNiPtRh'(Ni,Fe,Rh,Cu,Ir,Pt)S
2.CC.20MilleriteNiSTrig. 3m : R3m
2.CC.20MäkineniteNiSeTrig. 3m
2.CC.25MackinawiteFeSTet. 4/mmm(4/m2/m2/m) : P4/nmm
2.CC.30VavříniteNi2SbTe2Hex. 6/mmm(6/m2/m2/m) : P63/mmc
2.CC.30'Hexatestibiopanickelite'(Pd,Ni)(Sb,Te) ?Hex.
2.CC.35bCooperitePtSTet. 4/mmm(4/m2/m2/m) : P42/mmc
2.CC.35aVysotskitePdSTet. 4/m : P42/m
2.CC.35aBraggitePdPt3S4Tet. 4/m : P42/m
2.CC.45JacutingaitePt2HgSe3Trig. 3m(32/m) : P3m1
2.CC.50'Imgreite'NiTe (?)Hex.

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 SederholmiteHide

References for SederholmiteHide

Localities for SederholmiteHide

Showing 2 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.
Finland
 
  • North Ostrobothnia
Vuorelainen et al. (1964) +1 other reference
Vuorelainen et al. (1964)
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