Afghanite and Biotite Physical Properties
Tenacity
Not Available
  
Brittle
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.55-2.65
  
2.7-3.3
  
Fracture
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle, Conchoidal, Brittle
  
Uneven, Even, Yellow, White
  
Cleavage
Perfect {10 1 0}
  
Perfect on the {001}
  
Mohs Hardness
5.5-6
  
2.5-3.0
  
Chemical Composition
(Na,Ca,K) 8(Si,Al) 12O 24(SO 4,Cl,CO 3) 3(H 2O)Arthur Thomas , Gemstones (2009)
  
K(Mg,Fe++)3[AlSi3O10(OH,F)2
  
Afghanite and Biotite Chemical Formula
While comparing Afghanite and Biotite 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 Afghanite and Biotite chemical formula.
- Chemical formula of Afghanite- (Na,Ca,K) 8(Si,Al) 12O 24(SO 4,Cl,CO 3) 3(H 2O)Arthur Thomas , Gemstones (2009)
- Chemical formula of Biotite- K(Mg,Fe++)3[AlSi3O10(OH,F)2
Afghanite and Biotite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Afghanite and Biotite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Afghanite and Biotite Optical Properties during the identification of gemstone. Specific gravity of Afghanite is 2.7-3.3 whereas that of Biotite is 2.7-3.3.