Biotite and Andesine Physical Properties
Tenacity
Brittle
  
Brittle
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.7-3.3
  
2.65-2.69
  
Fracture
Uneven, Even, Yellow, White
  
Uneven, Uneven, Conchoidal, Uneven, Gems, Sixth Edition (2006)
  
Cleavage
Perfect on the {001}
  
Perfect on {001}, good on {010}
  
Mohs Hardness
2.5-3.0
  
6-6.5
  
Chemical Composition
K(Mg,Fe++)3[AlSi3O10(OH,F)2
  
(Na,Ca)Al1-2Si3-2O8
  
Biotite and Andesine Chemical Formula
While comparing Biotite and Andesine 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 Biotite and Andesine chemical formula.
- Chemical formula of Biotite- K(Mg,Fe++)3[AlSi3O10(OH,F)2
- Chemical formula of Andesine- (Na,Ca)Al1-2Si3-2O8
Biotite and Andesine Specific Gravity
Another important criteria for qualitative analysis of gemstones is Biotite and Andesine Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Biotite and Andesine Optical Properties during the identification of gemstone. Specific gravity of Biotite is 2.65-2.69 whereas that of Andesine is 2.65-2.69.