Template:Spinel

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Spinel
Chemical composition Mg(Al2O4) Magnesium aluminum oxide
Crystal system Cubic
Habit Octahedral, contact twins
Cleavage Imperfect
Fracture Conchoidal, uneven
Hardness 8
Optic nature Isotropic
Refractive index 1.712 - 1.736
Birefringence None
Dispersion 0.026
Specific gravity 3.58 - 3.61
Lustre Vitreous
Pleochroism None