General Information |
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A variety or type of: | Common Opal, which is a variety of Opal |
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Chemical Formula | Walter Schumann, Gemstones of the world (2001) |
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Physical Properties of Moss Opal |
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Mohs Hardness | 5.5 to 6.5Walter Schumann, Gemstones of the world (2001) |
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Specific Gravity | 1.98 to 2.50Walter Schumann, Gemstones of the world (2001) |
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Tenacity | BrittleWalter Schumann, Gemstones of the world (2001) |
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Cleavage Quality | NoneWalter Schumann, Gemstones of the world (2001) |
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Fracture | Conchoidal,SplinteryWalter Schumann, Gemstones of the world (2001) |
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Optical Properties of Moss Opal |
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Refractive Index | 1.37 to 1.52Walter Schumann, Gemstones of the world (2001) |
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Birefringence | NoneWalter Schumann, Gemstones of the world (2001) |
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Pleochroism | AbsentWalter Schumann, Gemstones of the world (2001) |
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Colour |
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Colour (General) | MilkyWalter Schumann, Gemstones of the world (2001) |
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Transparency | Translucent,OpaqueWalter Schumann, Gemstones of the world (2001) |
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Crystallography of Moss Opal |
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Crystal System | AmorphousWalter Schumann, Gemstones of the world (2001) |
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Inclusions in Moss Opal |
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Generally fine-grained chlorite, often mixed with clay minerals. - Opal, Lithographie, 2007, p. 59 |
Further Information |
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Mineral information: | Moss Opal information at mindat.org |
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Significant Gem Localities |
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| USA | |
| Laurs and Quinn (2003) |
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