Bertrandite and Blue John Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.59-2.60
  
3.00-3.25
  
Fracture
Brittle, Metallic, Brittle, Metallic
  
Not Available
  
Cleavage
{001} Perfect, {110} Distinct, {101} Distinct
  
Not Available
  
Mohs Hardness
6-7
  
Not Available
  
Chemical Composition
Be 4Si 2O 7(OH) 2Anthony et al , Handbook of mineralogy (2001)
  
CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
  
Bertrandite and Blue John Chemical Formula
While comparing Bertrandite 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 Bertrandite and Blue John chemical formula.
- Chemical formula of Bertrandite- Be 4Si 2O 7(OH) 2Anthony et al , Handbook of mineralogy (2001)
- Chemical formula of Blue John- CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
Bertrandite and Blue John Specific Gravity
Another important criteria for qualitative analysis of gemstones is Bertrandite and Blue John Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Bertrandite and Blue John Optical Properties during the identification of gemstone. Specific gravity of Bertrandite is 3.00-3.25 whereas that of Blue John is 3.00-3.25.