Cummingtonit

Structural context

Cummingtonite
Crystal System monoclinicCrystal Class prismaticSpace Group C2/m

Chemical context

Stoichiometric formulas

Cummingtonite
mindat.org
  • March 13, 2023◻{Mg2}{Mg5}(Si8O22)(OH)2Cummingtonite is defined as a monoclinic amphibole belong to the magnesium-iron-manganese amphibole subgroup. It is defined with Mg as the dominant element both in the B and C positions.
IMA
  • March 13, 2023◻Mg2Mg5Si8O22(OH)2
mineralogy.rocks
  • Aug. 30, 2022[box]Mg7Si8O22(OH)2

Physical properties

ColorColor entities, recognized using a custom trained NER model
  • dark green
      • colourless
      Color noteOriginal color note from the source
      Translucent dark green, brown, grey, colourless
      StreakStreak entities, recognized using a custom trained NER model
      Streak noteOriginal streak note from the source
      Nd
      Lustre
      Vitreous
      Transparency
      Transparent
      Translucent
      Luminescence
      Nonfluorescent
      Tenacity
      brittle
      Hardness
      5—6
      Measured density
      3.1—3.6
      Calculated density
      3.3