Achroite and Blue John Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.90-3.40
  
3.00-3.25
  
Fracture
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001)
  
Not Available
  
Cleavage
Not Available
  
Not Available
  
Mohs Hardness
7-7.5
  
Not Available
  
Chemical Composition
Na(Li 1.5Al 1.5)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012) Formula given for elbaite.
  
CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
  
Achroite and Blue John Chemical Formula
While comparing Achroite and Blue John 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 Achroite and Blue John chemical formula.
- Chemical formula of Achroite- Na(Li 1.5Al 1.5)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012) Formula given for elbaite.
- Chemical formula of Blue John- CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
Achroite and Blue John Specific Gravity
Another important criteria for qualitative analysis of gemstones is Achroite and Blue John Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Achroite and Blue John Optical Properties during the identification of gemstone. Specific gravity of Achroite is 3.00-3.25 whereas that of Blue John is 3.00-3.25.