Template:Diaspore

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Diaspore
Chemical composition AlO(OH)
Crystal system Orthorhombic
Habit Tabular, sometimes fibrous
Cleavage Perfect to imperfect
Fracture Conchoidal
Luster Bright vitreous to pearly (on cleavage surface).
Hardness 6.5 - 7
Optic nature Biaxial +
Refractive index 1.682 - 1.752
Birefringence 0.040 - 0.048
Specific gravity 3.2 - 3.5
Lustre Vitreous
Pleochroism Moderate