1 Astrology
1.1 Origin
Not Available, Southern and central Africa
Sri Lanka, India, Brazil
1.2 Color
Violet, Black
Green, Brown, Brown, Colorless, Green, gray, Yellow
1.3 Streak
gray, White, gray, White
Brownish, White, Brownish, White
1.4 For which Rashi?
Not Available
Not Available
1.5 Planet
Not Available
Not Available
1.6 Element of Planets
Not Available
Not Available
1.7 How to Wear?
1.7.1 Finger
Not Available
Not Available
1.7.2 Ring Metal
Not Available
Not Available
1.8 Energy
Not Available
Not Available
1.9 Deities
Not Available
Not Available
1.10 Not to wear with
Not Available
Not Available
1.11 Powers
Not Available
Not Available
1.12 Birthstone
1.12.1 Planetary
Not Available
Not Available
1.12.2 Talisman
Not Available
Not Available
2 Physical Properties
2.1 Tenacity
Not Available
Not Available
2.2 Solubility
Not Available
Not Available
2.3 Durability
Not Available
Not Available
2.4 Specific Gravity
2.5 Fracture
Handbook of mineralogy (2001)
Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
2.6 Cleavage
2.7 Mohs Hardness
2.8 Chemical Composition
Na x[Fe2+2(Al,Fe3+ )]Al 6(BO 3) 3Si 6O 18(OH) 4Anthony et al , Handbook of mineralogy (2001)
Ca 3Al 2(SiO 4) 3Arthur Thomas , Gemstones (2009)
3 Optical Properties
3.1 Luster
Vitreous
Greasy, Vitreous
3.2 Pleochroism
Strong: pale lavender dark blueAnthony et al
None
3.3 Dispersion
3.4 Transparency
TranslucentAnthony et al, Translucent
Gemmological Tables (2004) More from other references
3.5 Refractive Index
Not Available1.730-1.760
1
3.25
3.6 Optic Character
Not Available
Not Available
3.7 Crystal System
Trigonal Ditrigonal Pyramidal H-M Symbol (3m) Space Group: R 3m
cubic
3.8 Birefringence
Not Available0.020
0
0.296
3.9 Clarity
TranslucentAnthony et al
TransparentUlrich Henn and Claudio C. Milisenda
4 Benefits
4.1 Physical
4.1.1 Neurological
Not Available
Not Available
4.1.2 Cardiovascular
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4.1.3 Respiratory
Not Available
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4.1.4 Reproductive
Not Available
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4.1.5 Digestive
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4.2 Psychology
Not Available
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4.3 Healing
Not Available
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4.4 Qualities Associated
Not Available
Not Available