Black Opal and Howlite Physical Properties
Tenacity
Not Available
Not Available
Solubility
Not Available
Not Available
Durability
Not Available
Not Available
Specific Gravity
1.97-2.22
2.45-2.58
Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Cleavage
Not Available
None
Mohs Hardness
6-6.5
3-3.5
Chemical Composition
SiO 2 + H 2OUlrich Henn and Claudio C.
Ca 2B 5SiO 9(OH) 5Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Black Opal and Howlite Chemical Formula
While comparing Black Opal and Howlite 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 Howlite chemical formula.
- Chemical formula of Black Opal- SiO 2 + H 2OUlrich Henn and Claudio C.
- Chemical formula of Howlite- Ca 2B 5SiO 9(OH) 5Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Black Opal and Howlite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Black Opal and Howlite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Black Opal and Howlite Optical Properties during the identification of gemstone. Specific gravity of Black Opal is 2.45-2.58 whereas that of Howlite is 2.45-2.58.