Origin
Southern and central Africa
  
USA, Madagascar, India, Sri Lanka, Burma, Australia, Italy, Brazil
  
Color
White, Colorless, Blue, Red, Green, Yellow, Violet, Black, Green, Red, Blue, White
  
Blue, Green, Brownish, Greenish, Colorless, gray
  
Streak
Colorless
  
White
  
For which Rashi?
Not Available
  
Not Available
  
Planet
Not Available
  
Not Available
  
Element of Planets
Not Available
  
Not Available
  
How to Wear?
  
  
Finger
Not Available
  
Not Available
  
Ring Metal
Not Available
  
Not Available
  
Energy
Not Available
  
Not Available
  
Deities
Not Available
  
Not Available
  
Not to wear with
Not Available
  
Not Available
  
Powers
Not Available
  
Not Available
  
Birthstone
  
  
Planetary
Not Available
  
Not Available
  
Talisman
Not Available
  
Not Available
  
Tenacity
Not Available
  
Tough
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.03-3.18
  
3.20-3.26
  
Fracture
Uneven, Uneven, Irregular, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
  
Splintery
  
Cleavage
{???} Indistinct
  
{010} perfect
  
Mohs Hardness
7-7.5
  
6-7.5
  
Chemical Composition
Na(Mg 3)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012)
  
Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)
  
Luster
Vitreous
  
Vitreous, Subadamantine, Silky
  
Pleochroism
Very strong: pale yellow colorless
  
Colourless to pale brown to yellow
  
Dispersion
Not Available
  
Transparency
Transparent
  
Transparent, Translucent
  
Refractive Index
1.614-1.666
  
1.653-1.685
  
Optic Character
Not Available
  
Not Available
  
Crystal System
Trigonal Ditrigonal Pyramidal H-M Symbol (3m) Space Group: R 3m
  
Orthorhombic
  
Birefringence
0.014-0.032
  
0.020-0.022
  
Clarity
Transparent
  
Transparent
  
Physical
  
  
Neurological
Not Available
  
Not Available
  
Cardiovascular
Not Available
  
Not Available
  
Respiratory
Not Available
  
Not Available
  
Reproductive
Not Available
  
Not Available
  
Digestive
Not Available
  
Not Available
  
Psychology
Not Available
  
Not Available
  
Healing
Not Available
  
Not Available
  
Qualities Associated
Not Available
  
Not Available
  
Dravite Vs Sillimanite Fracture
Fracture is an important parameter when you compare Dravite and Sillimanite Physical Properties. It is necessary to understand the significance of these properties, before you compare Dravite Vs Sillimanite fracture. Whenever a gemstone chip breaks, it leaves a characteristic line along its breakage. Such lines are known as fracture and are used to identify the gemstones in their initial stages of production when they are in the form of rough minerals. Fracture is usually described with the terms “fibrous” and “splintery” to denote a fracture that usually leaves elongated and sharp edges. Fracture observed in Dravite is Brittle, Conchoidal, ConchoidalAnthony et al, Handbook of mineralogy (2001), Irregular, Uneven and Uneven. Sillimanite fracture is Splintery.
Dravite Vs Sillimanite Luster
A primary knowledge about Dravite vs Sillimanite luster is useful in apparent identifications of these gemstones. Luster is the measure of light that gets reflected when incident on a finished cut gemstone. There are two major types of lusters: Silky and Adamantine. Since luster varies between two crystals of even the same gemstone, luster is limited to basic identification criteria. Dravite exhibits Vitreous luster. Sillimanite, on other hand, exhibits Silky, Subadamantine and Vitreous luster.