Polyhalite and Bustamite Physical Properties
Tenacity
Brittle
  
Not Available
  
Solubility
Soluble
  
Partly soluble in HCl.
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.78
  
3.32-3.43
  
Fracture
Conchoidal, Brittle
  
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
  
Cleavage
Perfect on {10 1 }; parting on {010}
  
{100} perfect; {110} and {1 1 0} good; {010} poor
  
Mohs Hardness
3.5
  
5.5-6
  
Chemical Composition
Not Available
  
(Ca,Mn2+ )Si 3O 9Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
  
Polyhalite and Bustamite Chemical Formula
While comparing Polyhalite and Bustamite 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 Polyhalite and Bustamite chemical formula.
>- Chemical formula of Bustamite- (Ca,Mn2+ )Si 3O 9Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Polyhalite and Bustamite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Polyhalite and Bustamite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Polyhalite and Bustamite Optical Properties during the identification of gemstone. Specific gravity of Polyhalite is 3.32-3.43 whereas that of Bustamite is 3.32-3.43.