Franklinite and Blue John Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
5.05-5.22
  
3.00-3.25
  
Fracture
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001)
  
Not Available
  
Cleavage
None
  
Not Available
  
Mohs Hardness
5.5-6
  
Not Available
  
Chemical Composition
(Zn,Mn2+ ,Fe2+ )(Fe3+ ,Mn3+ ) 2O 4Anthony et al , Handbook of mineralogy (2001)
  
CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
  
Franklinite and Blue John Chemical Formula
While comparing Franklinite 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 Franklinite and Blue John chemical formula.
- Chemical formula of Franklinite- (Zn,Mn2+ ,Fe2+ )(Fe3+ ,Mn3+ ) 2O 4Anthony et al , Handbook of mineralogy (2001)
- Chemical formula of Blue John- CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
Franklinite and Blue John Specific Gravity
Another important criteria for qualitative analysis of gemstones is Franklinite and Blue John Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Franklinite and Blue John Optical Properties during the identification of gemstone. Specific gravity of Franklinite is 3.00-3.25 whereas that of Blue John is 3.00-3.25.