Monoclinic
Ca - Mg - Fe2+
Hornblende K(Ca,Na,K)2-3(Mg,Fe2+,Fe3+,Al,Ti)5[(OH,F)/(Al,Si)Si3O11]2

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Colour: green, brown Pleochroism: pleochroic Habit: prismatic, commonly cross sections are 6 sided Relief: positive Cleavage, fracture: in horizontal section - good, single cleavage, in cross sections - good, double cleavage at 124º
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Isotropic or anisotropic: anisotropic Extinction: inclined Interference colours: 1st/2nd order
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Lamprobolite K(Ca,Na,K)2-3(Mg,Fe2+,Fe3+,Al,Ti)5[(O,OH,F)/(Al,Si)Si3O11]2

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Colour: red, brown Pleochroism: pleochroic Habit: prismatic, cross sections are 6 sided Relief: positive Cleavage, fracture: in horizontal section - good, single cleavage, in cross sections - good, double cleavage at 124º
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Isotropic or anisotropic: anisotropic Extinction: inclined Interference colours: 1st/2nd order
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Last modified: Monday, 3 April 2017, 10:51 AM