Alunite and Sodalite Physical Properties
Tenacity
Brittle
  
Brittle
  
Solubility
Soluble
  
Soluble
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.6-2.9
  
2.15-2.40
  
Fracture
Conchoidal, Uneven
  
Conchoidal, Uneven, UnevenArthur Thomas, Brittle
  
Cleavage
On {0001}, perfect
  
Poor on {110}
  
Mohs Hardness
3.5-4
  
5-6
  
Chemical Composition
KAl3(SO4)2(OH)6
  
Na8Al6Si6O24Cl2
  
Alunite and Sodalite Chemical Formula
While comparing Alunite and Sodalite 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 Alunite and Sodalite chemical formula.
- Chemical formula of Alunite- KAl3(SO4)2(OH)6
- Chemical formula of Sodalite- Na8Al6Si6O24Cl2
Alunite and Sodalite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Alunite and Sodalite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Alunite and Sodalite Optical Properties during the identification of gemstone. Specific gravity of Alunite is 2.15-2.40 whereas that of Sodalite is 2.15-2.40.