| General Information |
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| A variety or type of: | Lignite |
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| Physical Properties of Jet |
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| Mohs Hardness | 2.5 to 4Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references |
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| Specific Gravity | 1.30 to 1.34Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references |
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| Fracture | ConchoidalArthur Thomas, Gemstones (2009) |
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| Optical Properties of Jet |
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| Refractive Index | 1.640 to 1.680Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) More from other references |
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| Optical Character | IsotropicUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) |
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| Colour |
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| Colour (General) | Black, brownUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Transparency | OpaqueUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Lustre | Waxy,DullGemdat.org, Management Team (2012) |
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| Crystallography of Jet |
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| Crystal System | AmorphousHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) |
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| Inclusions in Jet |
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| Hot needle: petroleum, coal odor (fossilized wood) - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 4 |
| Further Information |
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| Mineral information: | Jet information at mindat.org |
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| Significant Gem Localities |
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