Blue John and Bytownite Physical Properties
Tenacity
Not Available
  
Brittle
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.00-3.25
  
2.72-2.75
  
Fracture
Not Available
  
Uneven, Uneven, Gems, Sixth Edition (2006)
  
Cleavage
Not Available
  
Perfect on [001], good on [010], imperfect on [110]
  
Mohs Hardness
Not Available
  
6-6.5
  
Chemical Composition
CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
  
Ca(70-90%)Na(30-10%)(Al,Si)AlSi 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
  
Blue John and Bytownite Chemical Formula
While comparing Blue John and Bytownite 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 Blue John and Bytownite chemical formula.
- Chemical formula of Blue John- CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
- Chemical formula of Bytownite- Ca(70-90%)Na(30-10%)(Al,Si)AlSi 2O 8Michael OâDonoghue , Gems, Sixth Edition (2006)
Blue John and Bytownite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Blue John and Bytownite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Blue John and Bytownite Optical Properties during the identification of gemstone. Specific gravity of Blue John is 2.72-2.75 whereas that of Bytownite is 2.72-2.75.