Norbergite
Norbergite is named after its discovery locality at Norberg, Sweden.
Norbergite forms translucent to opaque, tan, yellow, yellow-orange, orange-brown, pink with purplish tint, white granular masses. Transparent crystals are very rare.
Norbergite is often cut into cabochons.
| General Information |
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| Chemical Formula | Anthony et al, Handbook of Mineralogy (2001) |
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| Photos of natural/un-cut material from mindat.org |
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| Physical Properties of Norbergite |
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| Mohs Hardness | 6 to 6.5Anthony et al, Handbook of Mineralogy (2001) |
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| Specific Gravity | 3.177Anthony et al, Handbook of Mineralogy (2001) |
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| Tenacity | BrittleAnthony et al, Handbook of Mineralogy (2001) |
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| Fracture | Uneven,Sub-ConchoidalAnthony et al, Handbook of Mineralogy (2001) |
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| Optical Properties of Norbergite |
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| Refractive Index | 1.563 to 1.593Anthony et al, Handbook of Mineralogy (2001) |
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| Optical Character | Biaxial/+Anthony et al, Handbook of Mineralogy (2001) |
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| Pleochroism | Pale yellow - very pale yellow - colorlessAnthony et al, Handbook of Mineralogy (2001) |
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| Colour |
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| Colour (General) | Tan, yellow, yellow-orange, orange-brown, pink with purplish tint, white; in thin section, pale yellow to colorlessAnthony et al, Handbook of Mineralogy (2001) |
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| Transparency | Transparent,TranslucentAnthony et al, Handbook of Mineralogy (2001) |
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| Lustre | Vitreous,ResinousAnthony et al, Handbook of Mineralogy (2001) |
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| Fluorescence & other light emissions |
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| Fluorescence (Short Wave UV) | May fluoresce canary-yellowAnthony et al, Handbook of Mineralogy (2001) |
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| Crystallography of Norbergite |
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| Crystal System | OrthorhombicAnthony et al, Handbook of Mineralogy (2001) |
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| Habit | Crystals rare, to 2.5 cm, thick tabular, typically rounded and highly modified; granular.Anthony et al, Handbook of Mineralogy (2001) |
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| Geological Environment |
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| Where found: | In contact metamorphic zones in limestones and dolostones into which plutonic rocks or pegmatites have introduced fluorine.Anthony et al, Handbook of Mineralogy (2001) |
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| Further Information |
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| Mineral information: | Norbergite information at mindat.org |
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| Significant Gem Localities |
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