1 Astrology
1.1 Origin
Southern and central Africa
Mexico
1.3 Color
Not Available
Blue, Blue, Black
1.4 Streak
Not Available
Grey, Black, gray
1.5 For which Rashi?
Not Available
Not Available
1.7 Planet
Not Available
Not Available
1.10 Element of Planets
Not Available
Not Available
1.12 How to Wear?
1.12.2 Finger
Not Available
Not Available
1.12.4 Ring Metal
Not Available
Not Available
1.14 Energy
Not Available
Not Available
1.16 Deities
Not Available
Not Available
1.18 Not to wear with
Not Available
Not Available
1.20 Powers
Not Available
Not Available
1.22 Birthstone
1.22.2 Planetary
Not Available
Not Available
1.22.4 Talisman
Not Available
Not Available
3 Physical Properties
3.2 Tenacity
3.4 Solubility
Not Available
Not Available
3.6 Durability
Not Available
Not Available
3.8 Specific Gravity
3.10 Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Metallic
3.12 Cleavage
Not Available
Perfect on {0001}
3.14 Mohs Hardness
3.16 Chemical Composition
Mg 3(Al,Cr) 2(SiO 4) 3Gemdat.org , Management Team (2012)
CuSMichael OâDonoghue , Gems, Sixth edition (2006) More from other references
5 Optical Properties
5.1 Luster
5.3 Pleochroism
5.5 Dispersion
5.8 Transparency
Gemmological Tables (2004)
OpaqueAnthony et al, Handbook of mineralogy (2001) More from other references
5.9 Refractive Index
1.720-1.7401.45-2.62
1
3.25
5.13 Optic Character
Not Available
Not Available
5.14 Crystal System
5.15 Birefringence
Not AvailableNot Available
0
0.296
6.3 Clarity
TransparentUlrich Henn and Claudio C. Milisenda
OpaqueAnthony et al
7 Benefits
7.1 Physical
7.1.1 Neurological
Not Available
Not Available
7.1.2 Cardiovascular
Not Available
Not Available
7.1.3 Respiratory
Not Available
Not Available
7.1.4 Reproductive
Not Available
Not Available
7.1.5 Digestive
Not Available
Not Available
7.2 Psychology
Not Available
Not Available
7.3 Healing
Not Available
Not Available
7.4 Qualities Associated
Not Available
Not Available