1 Astrology
1.1 Origin
India, Southern and central Africa, Madagascar
Tanzania, Madagascar, Kenya, Sri Lanka, Burma, Australia
1.2 Color
Black, Brownish, Greenish
Green, Brown, Colorless, Greenish, Yellow
1.3 Streak
1.4 For which Rashi?
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1.5 Planet
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1.6 Element of Planets
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1.7 How to Wear?
1.7.1 Finger
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1.7.2 Ring Metal
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1.8 Energy
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1.9 Deities
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1.10 Not to wear with
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1.11 Powers
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1.12 Birthstone
1.12.1 Planetary
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1.12.2 Talisman
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2 Physical Properties
2.1 Tenacity
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2.2 Solubility
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2.3 Durability
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2.4 Specific Gravity
3.18-3.223.25-3.45
1
7.18
2.5 Fracture
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Brittle, Uneven
2.6 Cleavage
{1011} Indistinct
Good on {110}
2.7 Mohs Hardness
2.8 Chemical Composition
Na(Fe2+3)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012)
Mg 3Al 6(Si,Al,B) 5O 21(OH)Walter Schumann , Gemstones of the world (2001) More from other references
3 Optical Properties
3.1 Luster
3.2 Pleochroism
Very strong: yellow-brown pale yellow
X = colorless to green; Y = colorless
3.3 Dispersion
3.4 Transparency
Transparent, Translucent
Gemmological Tables (2004) More from other references
3.5 Refractive Index
1.635-1.6721.660-1.685
1
3.25
3.6 Optic Character
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3.7 Crystal System
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Orthorhombic
3.8 Birefringence
3.9 Clarity
Transparent
TransparentUlrich Henn and Claudio C. Milisenda
4 Benefits
4.1 Physical
4.1.1 Neurological
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4.1.2 Cardiovascular
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4.1.3 Respiratory
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4.1.4 Reproductive
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4.1.5 Digestive
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4.2 Psychology
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4.3 Healing
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4.4 Qualities Associated
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