Lapis lazuli and Sillimanite Physical Properties
Tenacity
Not Available
Tough
Solubility
Not Available
Not Available
Durability
Not Available
Not Available
Specific Gravity
2.50-3.00
3.20-3.26
Fracture
Uneven-Conchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001)
Splintery
Cleavage
3,6
{010} perfect
Chemical Composition
The chief constituent Lapis Lazuli is Lazurite, with the following chemical formula: (Na,Ca)8Al6Si6O24(S,SO)4
Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)
Lapis lazuli and Sillimanite Chemical Formula
While comparing Lapis lazuli 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 Lapis lazuli and Sillimanite chemical formula.
- Chemical formula of Lapis lazuli- The chief constituent Lapis Lazuli is Lazurite, with the following chemical formula: (Na,Ca)8Al6Si6O24(S,SO)4
- Chemical formula of Sillimanite- Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)
Lapis lazuli and Sillimanite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Lapis lazuli and Sillimanite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Lapis lazuli and Sillimanite Optical Properties during the identification of gemstone. Specific gravity of Lapis lazuli is 3.20-3.26 whereas that of Sillimanite is 3.20-3.26.