Common 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
1.98-2.50
4.12
Fracture
Conchoidal, Conchoidal, Gemstones of the world (2001)
Brittle, Uneven, Brittle, Uneven
Cleavage
Not Available
Good in two directions parallel to the prism faces {110}
Mohs Hardness
5.5-6.5
4-4.5
Chemical Composition
SiO 2 · nH 2OWalter Schumann , Gemstones of the world (2001)
CaZn(AsO4)(OH)
Common Opal and Austinite Chemical Formula
While comparing Common 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 Common Opal and Austinite chemical formula.
- Chemical formula of Common Opal- SiO 2 · nH 2OWalter Schumann , Gemstones of the world (2001)
- Chemical formula of Austinite- CaZn(AsO4)(OH)
Common Opal and Austinite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Common Opal and Austinite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Common Opal and Austinite Optical Properties during the identification of gemstone. Specific gravity of Common Opal is 4.12 whereas that of Austinite is 4.12.