Black Opal and Gahnite Physical Properties
Tenacity
Not Available
Not Available
Solubility
Not Available
Not Available
Durability
Not Available
Not Available
Specific Gravity
1.97-2.22
4.00-4.62
Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Conchoidal, Uneven
Cleavage
Not Available
Indistinct parting on [111]
Mohs Hardness
6-6.5
7.5-8
Chemical Composition
SiO 2 + H 2OUlrich Henn and Claudio C.
ZnAl 2O 4Michael OâDonoghue , Gems, Sixth Edition (2006)
Black Opal and Gahnite Chemical Formula
While comparing Black Opal and Gahnite 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 Black Opal and Gahnite chemical formula.
- Chemical formula of Black Opal- SiO 2 + H 2OUlrich Henn and Claudio C.
- Chemical formula of Gahnite- ZnAl 2O 4Michael OâDonoghue , Gems, Sixth Edition (2006)
Black Opal and Gahnite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Black Opal and Gahnite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Black Opal and Gahnite Optical Properties during the identification of gemstone. Specific gravity of Black Opal is 4.00-4.62 whereas that of Gahnite is 4.00-4.62.