Alunite and Topaz Physical Properties
Tenacity
Brittle
  
Not Available
  
Solubility
Soluble
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.6-2.9
  
3.49-3.57
  
Fracture
Conchoidal, Uneven
  
Subconchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle
  
Cleavage
On {0001}, perfect
  
[001] Perfect
  
Mohs Hardness
3.5-4
  
8
  
Chemical Composition
KAl3(SO4)2(OH)6
  
Al2SiO4(F,OH)2
  
Alunite and Topaz Chemical Formula
While comparing Alunite and Topaz 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 Topaz chemical formula.
- Chemical formula of Alunite- KAl3(SO4)2(OH)6
- Chemical formula of Topaz- Al2SiO4(F,OH)2
Alunite and Topaz Specific Gravity
Another important criteria for qualitative analysis of gemstones is Alunite and Topaz Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Alunite and Topaz Optical Properties during the identification of gemstone. Specific gravity of Alunite is 3.49-3.57 whereas that of Topaz is 3.49-3.57.