Boulder Opal and Austinite Physical Properties
Tenacity
Not Available
  
Brittle
  
Solubility
Not Available
  
Easily soluble in cold dilute HCl
  
Durability
Not Available
  
Not Available
  
Specific Gravity
1.98-2.25
  
4.12
  
Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
  
Brittle, Uneven, Brittle, Uneven
  
Cleavage
Not Available
  
Good in two directions parallel to the prism faces {110}
  
Mohs Hardness
5-6.5
  
4-4.5
  
Chemical Composition
SiO 2 + H 2OUlrich Henn and Claudio C.
  
CaZn(AsO4)(OH)
  
Boulder Opal and Austinite Chemical Formula
While comparing Boulder Opal and Austinite 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 Boulder Opal and Austinite chemical formula.
- Chemical formula of Boulder Opal- SiO 2 + H 2OUlrich Henn and Claudio C.
- Chemical formula of Austinite- CaZn(AsO4)(OH)
Boulder Opal and Austinite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Boulder Opal and Austinite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Boulder Opal and Austinite Optical Properties during the identification of gemstone. Specific gravity of Boulder Opal is 4.12 whereas that of Austinite is 4.12.