Iolite and Biotite Physical Properties
Tenacity
Not Available
  
Brittle
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.6-2.7
  
2.7-3.3
  
Fracture
Not Available
  
Uneven, Even, Yellow, White
  
Cleavage
3,1
  
Perfect on the {001}
  
Mohs Hardness
7-7.5
  
2.5-3.0
  
Chemical Composition
Mg2Al4Si5O18
  
K(Mg,Fe++)3[AlSi3O10(OH,F)2
  
Iolite and Biotite Chemical Formula
While comparing Iolite 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 Iolite and Biotite chemical formula.
- Chemical formula of Iolite- Mg2Al4Si5O18
- Chemical formula of Biotite- K(Mg,Fe++)3[AlSi3O10(OH,F)2
Iolite and Biotite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Iolite and Biotite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Iolite and Biotite Optical Properties during the identification of gemstone. Specific gravity of Iolite is 2.7-3.3 whereas that of Biotite is 2.7-3.3.