Template:Siderite

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Siderite
Chemical composition FeCO3
Crystal system Trigonal
Habit Rhombohedrons, ganular, oolites
Cleavage Perfect, rhombohedral {101}
Fracture
Hardness 3.5 - 4.5
Optic nature Uniaxial -
Refractive index 1.633 - 1.875
Birefringence 0.240
Dispersion
Specific gravity 3.83-3.88 (upto 3.96)
Lustre Vitreous, pearly, silky or dull
Pleochroism