Knopite

A variety of perovskite rich in cerium. Originally described from Långörsholmen, Alnö, Sundsvall, Medelpad, Sweden.

Structural context

Perovskite
Crystal System orthorhombicCrystal Class orthorhombic dipyramidalSpace Group Pnma

Chemical context

Stoichiometric formulas

Knopite
mindat.org
  • March 13, 2023(Ca,Ce,Na)(Ti,Fe)O3
mineralogy.rocks
  • Aug. 30, 2022(Ca,Ce3+,Na)(Ti4+,Fe3+)O3
Perovskite
mindat.org
  • March 13, 2023CaTiO3
IMA
  • March 13, 2023CaTiO3
mineralogy.rocks
  • Aug. 30, 2022CaTi4+O3

Physical properties

ColorColor entities, recognized using a custom trained NER model
  • dark brown
  • red-brown
      Color noteOriginal color note from the source
      Dark brown, black, red-brown, yellow shades
      StreakStreak entities, recognized using a custom trained NER model
      • colourless
      • greyish white
      Streak noteOriginal streak note from the source
      Colourless, greyish white
      Lustre
      Adamantine
      Metallic
      Sub-Metallic
      Fracture
      Irregular/Uneven
      Sub-Conchoidal
      Transparency
      Transparent
      Translucent
      Tenacity
      brittle
      Hardness
      5.5
      Measured density
      3.98—4.26
      Calculated density
      4.02