Blue John and Howlite Physical Properties
Tenacity
Not Available
Not Available
Solubility
Not Available
Not Available
Durability
Not Available
Not Available
Specific Gravity
3.00-3.25
2.45-2.58
Fracture
Not Available
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Cleavage
Not Available
None
Mohs Hardness
Not Available
3-3.5
Chemical Composition
CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
Ca 2B 5SiO 9(OH) 5Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Blue John and Howlite Chemical Formula
While comparing Blue John 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 Blue John and Howlite chemical formula.
- Chemical formula of Blue John- CaF 2Michael OâDonoghue , Gems, Sixth Edition (2006)
- Chemical formula of Howlite- Ca 2B 5SiO 9(OH) 5Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Blue John and Howlite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Blue John and Howlite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Blue John and Howlite Optical Properties during the identification of gemstone. Specific gravity of Blue John is 2.45-2.58 whereas that of Howlite is 2.45-2.58.