Apophyllite KF and Blue John Physical Properties
Tenacity
Brittle
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.33-2.37
  
3.00-3.25
  
Fracture
Uneven, Brittle, Uneven, Brittle, Uneven
  
Not Available
  
Cleavage
Perfect on {001}, imperfect on {110}
  
Not Available
  
Mohs Hardness
4.5-5
  
Not Available
  
Chemical Composition
(K,Na)Ca4Si8O20(F,OH)•8(H2O)
  
CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
  
Apophyllite KF and Blue John Chemical Formula
While comparing Apophyllite KF 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 Apophyllite KF and Blue John chemical formula.
- Chemical formula of Apophyllite KF- (K,Na)Ca4Si8O20(F,OH)•8(H2O)
- Chemical formula of Blue John- CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
Apophyllite KF and Blue John Specific Gravity
Another important criteria for qualitative analysis of gemstones is Apophyllite KF and Blue John Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Apophyllite KF and Blue John Optical Properties during the identification of gemstone. Specific gravity of Apophyllite KF is 3.00-3.25 whereas that of Blue John is 3.00-3.25.