Blue John and Purpurite Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.00-3.25
  
3.2-3.4
  
Fracture
Not Available
  
Uneven, UnevenArthur Thomas, Gemstones (2009), Brittle
  
Cleavage
Not Available
  
[100] [001] perfect
  
Mohs Hardness
Not Available
  
4-4.5
  
Chemical Composition
CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
  
MnPO 4Walter Schumann , Gemstones of the world (2001) More from other references
  
Blue John and Purpurite Chemical Formula
While comparing Blue John and Purpurite 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 Purpurite chemical formula.
- Chemical formula of Blue John- CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
- Chemical formula of Purpurite- MnPO 4Walter Schumann , Gemstones of the world (2001) More from other references
Blue John and Purpurite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Blue John and Purpurite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Blue John and Purpurite Optical Properties during the identification of gemstone. Specific gravity of Blue John is 3.2-3.4 whereas that of Purpurite is 3.2-3.4.