1 Astrology
1.1 Origin
Not Available, Southern and central Africa
Mexico, Thailand, Italy, Austria
1.2 Color
Violet, Black
Green, Brown, Colorless, Greenish, gray, Yellow, White
1.3 Streak
gray, White, gray, White
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
2.2 Solubility
2.3 Durability
Not Available
Not Available
2.4 Specific Gravity
2.5 Fracture
Handbook of mineralogy (2001)
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Conchoidal, Brittle
2.6 Cleavage
None
Perfect on {110}, poor on {101}, {001} rare
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)
Zn 4Si 2O 7(OH) 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
3 Optical Properties
3.1 Luster
Vitreous
Vitreous, Adamantine, Silky
3.2 Pleochroism
Strong: pale lavender dark blueAnthony et al
AbsentWalter Schumann
3.3 Dispersion
3.4 Transparency
TranslucentAnthony et al, Translucent
Transparent, Translucent
3.5 Refractive Index
Not Available1.614-1.636
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
Orthorhombic
3.8 Birefringence
Not Available0.022
0
0.296
3.9 Clarity
TranslucentAnthony et al
Transparent
4 Benefits
4.1 Physical
4.1.1 Neurological
Not Available
Not Available
4.1.2 Cardiovascular
Not Available
Not Available
4.1.3 Respiratory
Not Available
Not Available
4.1.4 Reproductive
Not Available
Not Available
4.1.5 Digestive
Not Available
Not Available
4.2 Psychology
Not Available
Not Available
4.3 Healing
Not Available
Not Available
4.4 Qualities Associated
Not Available
Not Available