Enstatite
Mg2(Si2O6)
Chemical name
Enstatite
Mineral name
Enstatite
Chemical formula
Mg2(Si2O6)
Crystal system
orthorhombic
Crystal Class
Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m)
Space Group
Pbca
Unit cell
a [Å]:18,23
b [Å]:8,84
c [Å]:5,19
Molecular weight [g/mol]
100387
Formula units
Z = 8
Twinning
Simple and lamellar on [100]
Mohs hardness
5 to 6
Fracture / Tenacity
Uneven, brittle
Color
White, grey, green, yellow or brown - colorless in thin section.
Streak
Gray
Optical character
Biaxial (+)
Refractive Index
nα = 1.650–1.668; nβ = 1.652–1.673; nΥ = 1.659–1.679
Birefringence δ
0.009–0.011
Pleochroism δ
Pale green to pale orange