Anorthite and Opal Physical Properties
Tenacity
Brittle
  
BrittleWalter Schumann
  
Solubility
Not Available
  
hot salt water
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.77
  
1.98-2.25
  
Fracture
Uneven, Uneven, Gems, Sixth Edition (2006)
  
Conchoidal, Conchoidal, Gemstones of the world (2001) More from other references, Brittle
  
Cleavage
Perfect [001] good [010] poor [110]
  
None
  
Mohs Hardness
6-6.5
  
5-6.5
  
Chemical Composition
CaAl 2Si 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
  
SiO2 · nH2O
  
Anorthite and Opal Chemical Formula
While comparing Anorthite and Opal 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 Anorthite and Opal chemical formula.
- Chemical formula of Anorthite- CaAl 2Si 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
- Chemical formula of Opal- SiO2 · nH2O
Anorthite and Opal Specific Gravity
Another important criteria for qualitative analysis of gemstones is Anorthite and Opal Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Anorthite and Opal Optical Properties during the identification of gemstone. Specific gravity of Anorthite is 1.98-2.25 whereas that of Opal is 1.98-2.25.