| General Information |
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| A variety or type of: | Beryl |
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| Other Names/Trade Names: | |
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| Heliodor Treatments |
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| Color may be improved by heat-treatment or be created by irradiation of colorless variety - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 6 |
| Physical Properties of Heliodor |
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| Mohs Hardness | 7.5 to 8Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) |
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| Specific Gravity | 2.68 to 2.72Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) |
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| Tenacity | BrittleWalter Schumann, Gemstones of the world (2001) |
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| Cleavage Quality | IndistinctWalter Schumann, Gemstones of the world (2001) |
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| Fracture | ConchoidalWalter Schumann, Gemstones of the world (2001) |
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| Optical Properties of Heliodor |
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| Refractive Index | 1.566 to 1.579Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) |
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| Optical Character | Uniaxial/-Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) |
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| Birefringence | 0.005 to 0.006Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Pleochroism | Weak: golden-yellow, green-yellowWalter Schumann, Gemstones of the world (2001) |
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| Dispersion | 0.014Walter Schumann, Gemstones of the world (2001) |
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| Chatoyancy | YesUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) |
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| Colour |
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| Colour (General) | Yellow-greenUlrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) More from other references |
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| Causes of Colour | The golden yellow color is attributed to Fe3+ ions.Color in the Beryl group. (2009) |
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| Transparency | Transparent,Translucent,OpaqueWalter Schumann, Gemstones of the world (2001) |
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| Crystallography of Heliodor |
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| Crystal System | HexagonalHerve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) |
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| Habit | Hexagonal prismsWalter Schumann, Gemstones of the world (2001) |
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| Inclusions in Heliodor |
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| Planes of tiny 2 phase inclusions - Blue Chart Gem Identification, Herve Nicolas Lazzarelli, 2010, p 6 |
| Further Information |
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| Mineral information: | Heliodor information at mindat.org |
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| Significant Gem Localities |
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| Afghanistan | | |
| Glas (2002) | | Brazil | | |
| Menezes (2005) | |
| Cassedanne and Alves (1994) | |
| Cassedanne and Alves (1994) |
- Pedra Azul pegmatite district
| Cassedanne and Alves (1994) | | Madagascar | | |
| Pezzotta (2001) | |
| Laurs and Quinn (2002) | | Namibia | | |
| Glas (2002), Laurs (2002) |
- Klein Spitzkopje granite stock (Kleine Spitzkoppe; Klein Spitzkoppe)
| Jahn (2000), Jahn and Bahmann (2000), Glas (2002), Laurs (2002) | | Nigeria | | |
| J. Micheou (2009) | | Russia | | |
| Emlin (1996) | | Sri Lanka | | |
| Dissanayake et al. (2000) | | Ukraine | | |
| Koivula et al. (1993), Lyckberg (2005) | | USA | | |
| Jarnot (2005) | |
| Sinkankas (1997) | |
| Wise (2005) | |
| Wise (2005) | | Zimbabwe | | |
| Shmakin and Wedepohl (1999), Milisenda et al. (2000) | |
| Milisenda et al. (2000), Cairncross (2005), Wise (2005) |
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