Goethite - Alfa iron oxy Hydroxide
α-FeO(OH)
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Crystal system
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Orthorhombic 2/m2/m2/m
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Color
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Yellowish to dark brown
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Clavage
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Perfect 010
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Fracture
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uneven to splintery
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Mohs scale hardness
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5 - 5.5
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Specific gravity
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3.3 - 3.4
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Refractiveindex
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Opaque to sub-translucent
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Unit Ce4
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a = 4.65 Å b = 10.02 Å c = 3.04 Å
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