Howlite and Sillimanite Physical Properties
Tenacity
Not Available
Tough
Solubility
Not Available
Not Available
Durability
Not Available
Not Available
Specific Gravity
2.45-2.58
3.20-3.26
Fracture
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Splintery
Cleavage
None
{010} perfect
Mohs Hardness
3-3.5
6-7.5
Chemical Composition
Ca 2B 5SiO 9(OH) 5Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)
Howlite and Sillimanite Chemical Formula
While comparing Howlite and Sillimanite 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 Howlite and Sillimanite chemical formula.
- Chemical formula of Howlite- Ca 2B 5SiO 9(OH) 5Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
- Chemical formula of Sillimanite- Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)
Howlite and Sillimanite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Howlite and Sillimanite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Howlite and Sillimanite Optical Properties during the identification of gemstone. Specific gravity of Howlite is 3.20-3.26 whereas that of Sillimanite is 3.20-3.26.