Sillimanit

Structural context

Sillimanite
Crystal System orthorhombicCrystal Class orthorhombic dipyramidalSpace Group Pnma

Chemical context

Stoichiometric formulas

Sillimanite
mindat.org
  • March 13, 2023Al2(SiO4)O
IMA
  • March 13, 2023Al2SiO5
mineralogy.rocks
  • Aug. 30, 2022Al2O(SiO4)

Physical properties

ColorColor entities, recognized using a custom trained NER model
  • colorless
            • gray
            Color noteOriginal color note from the source
            Colorless, white, yellow, brown, green, blue, gray.
            StreakStreak entities, recognized using a custom trained NER model
              Streak noteOriginal streak note from the source
              White
              Lustre
              Sub-Vitreous
              Greasy
              Silky
              Fracture
              Irregular/Uneven
              Transparency
              Transparent
              Translucent
              Tenacity
              brittle
              Hardness
              6.5—7.5
              Measured density
              3.23—3.27
              Calculated density
              3.24