| General Information |
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| Chemical Formula | Walter Schumann, Gemstones of the world (2001) More from other references |
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| Physical Properties of Purpurite |
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| Mohs Hardness | 4 to 4.5Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Specific Gravity | 3.2 to 3.4Walter Schumann, Gemstones of the world (2001) More from other references |
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| Tenacity | BrittleWalter Schumann, Gemstones of the world (2001) More from other references |
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| Cleavage Quality | DistinctUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Fracture | UnevenArthur Thomas, Gemstones (2009) |
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| Optical Properties of Purpurite |
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| Refractive Index | 1.85 to 1.92Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Optical Character | Biaxial/+Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Birefringence | 0.07Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Pleochroism | StrongArthur Thomas, Gemstones (2009) More from other references |
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| Dispersion | Relatively strongArthur Thomas, Gemstones (2009) More from other references |
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| Colour |
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| Colour (General) | Purple, deep pink, dark brownWalter Schumann, Gemstones of the world (2001) More from other references |
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| Transparency | TranslucentWalter Schumann, Gemstones of the world (2001) More from other references |
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| Lustre | MetallicWalter Schumann, Gemstones of the world (2001) More from other references |
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| Crystallography of Purpurite |
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| Crystal System | OrthorhombicUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Habit | MassiveArthur Thomas, Gemstones (2009) More from other references |
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| Geological Environment |
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| Where found: | Derived from oxidation and leaching of primary Mn–Fe phosphates, particularly lithiophilite, in complex granite pegmatites; rarely, formed by reaction between bat guano and Fe–Mn deposits resulting from seawater ingress.Anthony et al, Handbook of Mineralogy (2001) |
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| Further Information |
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| Mineral information: | Purpurite information at mindat.org |
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