Siegenit

Structural context

Siegenite
Crystal System isometricCrystal Class hexoctahedralSpace Group Fd-3m

Chemical context

Stoichiometric formulas

Siegenite
mindat.org
  • March 13, 2023CoNi2S4CoNi2S4 is the IMA-approved formula. The mineral was previously also incorrectly defined by a range of composition: CoNi2S4-NiCo2S4 (the latter composition is grimmite). The pure Co- and Ni-endmembers are linnaeite and polydymite, respectively.
IMA
  • March 13, 2023CoNi2S4
mineralogy.rocks
  • Aug. 30, 2022Co2+Ni3+2S2-4

Physical properties

ColorColor entities, recognized using a custom trained NER model
  • light
  • steel-grey
  • violet-gray
Color noteOriginal color note from the source
Light to steel-grey, violet-gray (tarnished)
StreakStreak entities, recognized using a custom trained NER model
  • greyish black
Streak noteOriginal streak note from the source
Greyish black
Lustre
Metallic
Fracture
Irregular/Uneven
Sub-Conchoidal
Transparency
Opaque
Hardness
4.5—5.5
Measured density
4.5—4.8
Calculated density
4.83