| 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 Simpsonite |
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| Mohs Hardness | 6.5 to 7Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Specific Gravity | 5.90 to 7.30Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Tenacity | BrittleArthur Thomas, Gemstones (2009) |
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| Cleavage Quality | IndistinctArthur Thomas, Gemstones (2009) |
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| Fracture | ConchoidalAnthony et al, Handbook of mineralogy (2001) |
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| Optical Properties of Simpsonite |
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| Refractive Index | 1.994 to 2.040Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Optical Character | Uniaxial/-Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Birefringence | 0.046Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Pleochroism | NilArthur Thomas, Gemstones (2009) |
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| Dispersion | NilArthur Thomas, Gemstones (2009) |
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| Colour |
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| Colour (General) | Yellowish, brownishUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Transparency | TranslucentUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Lustre | AdamantineMichael O’Donoghue, Gems, Sixth Edition (2006) More from other references |
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| Fluorescence & other light emissions |
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| Fluorescence (Short Wave UV) | Crystals from western Australia show a bright blue-whiteMichael O’Donoghue, Gems, Sixth Edition (2006) More from other references |
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| Crystallography of Simpsonite |
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| Crystal System | TrigonalUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Habit | Tabular to short prismaticMichael O’Donoghue, Gems, Sixth Edition (2006) More from other references |
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| Geological Environment |
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| Where found: | Simpsonite occurs as an accessory mineral in some Ta-rich granite pegmatites.Michael O’Donoghue, Gems, Sixth Edition (2006) More from other references |
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| Further Information |
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| Mineral information: | Simpsonite information at mindat.org |
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| Significant Gem Localities |
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| Australia | | |
| Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 452 | | Brazil | | |
| Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 452 |
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