| General Information |
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| Chemical Formula | Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Physical Properties of Staurolite |
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| Mohs Hardness | 7 to 7.5Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references |
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| Specific Gravity | 3.65 to 3.77Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) 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 | Sub-ConchoidalArthur Thomas, Gemstones (2009) |
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| Optical Properties of Staurolite |
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| Refractive Index | 1.736 to 1.762Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references |
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| Optical Character | Biaxial/+Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references |
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| Birefringence | 0.013Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Pleochroism | Distinct: light yellow - yellowish red - dark redHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references |
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| Dispersion | NilArthur Thomas, Gemstones (2009) |
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| Colour |
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| Colour (General) | Colourless, yellowish, reddish, brownishUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Causes of Colour | Brown, Fe2+ in tetrahedral coordination. Blue, Co2+ in tetrahedral coordinationW. William Hanneman, Pragmatic Spectroscopy For Gemologists (2011) |
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| Transparency | Transparent,Translucent,OpaqueUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Lustre | Vitreous,ResinousArthur Thomas, Gemstones (2009) |
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| Crystallography of Staurolite |
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| Crystal System | OrthorhombicUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Habit | Pseudo-orthorhombic prismaticMichael O’Donoghue, Gems, Sixth Edition (2006) More from other references |
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| Geological Environment |
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| Where found: | Staurolite occurs most commonly in schists and gneisses.Michael O’Donoghue, Gems, Sixth Edition (2006) |
| Further Information |
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| Mineral information: | Staurolite information at mindat.org |
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| Significant Gem Localities |
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| Brazil | | |
| Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 455 | | Switzerland | | |
| Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 455 |
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