Sillimanite and Anhydrite Physical Properties
Tenacity
Tough
  
Brittle
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.20-3.26
  
2.90-2.98
  
Fracture
Splintery
  
Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
  
Cleavage
{010} perfect
  
Rare tabular and prismatic crystals. Usually occurs as fibrous, parallel veins that break off into cleavage fragments.
  
Mohs Hardness
6-7.5
  
3.5
  
Chemical Composition
Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)
  
CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
  
Sillimanite and Anhydrite Chemical Formula
While comparing Sillimanite and Anhydrite physical properties, the important data you should know is its chemical composition. Since chemical formula defines the molecular structure of the crystal, most of the physical properties like color, tenacity, solubility are governed by Sillimanite and Anhydrite chemical formula.
- Chemical formula of Sillimanite- Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)
- Chemical formula of Anhydrite- CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
Sillimanite and Anhydrite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Sillimanite and Anhydrite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Sillimanite and Anhydrite Optical Properties during the identification of gemstone. Specific gravity of Sillimanite is 2.90-2.98 whereas that of Anhydrite is 2.90-2.98.