Polyhalite and Omphacite Physical Properties
Tenacity
Brittle
  
Not Available
  
Solubility
Soluble
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.78
  
3.16-3.43
  
Fracture
Conchoidal, Brittle
  
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
  
Cleavage
Perfect on {10 1 }; parting on {010}
  
{110} Good, {110} Good
  
Mohs Hardness
3.5
  
5-6
  
Chemical Composition
Not Available
  
(Ca,Na)(Mg,Fe,Al)Si 2O 6Anthony et al , Handbook of Mineralogy (2001)
  
Polyhalite and Omphacite Chemical Formula
While comparing Polyhalite and Omphacite 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 Omphacite chemical formula.
>- Chemical formula of Omphacite- (Ca,Na)(Mg,Fe,Al)Si 2O 6Anthony et al , Handbook of Mineralogy (2001)
Polyhalite and Omphacite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Polyhalite and Omphacite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Polyhalite and Omphacite Optical Properties during the identification of gemstone. Specific gravity of Polyhalite is 3.16-3.43 whereas that of Omphacite is 3.16-3.43.