Petalite and Amethyst Physical Properties
Tenacity
Brittle
Not Available
Solubility
insoluble
insoluble in common solvents
Durability
Not Available
Not Available
Specific Gravity
2.40
2.65
Fracture
Subconchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Conchoidal
Conchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001)
Cleavage
Perfect on {001}, poor on {201} with 38.5° angle between the two
Indiscernible
Chemical Composition
LiAlSi 4O 10Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
SiO2
Petalite and Amethyst Chemical Formula
While comparing Petalite and Amethyst 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 Petalite and Amethyst chemical formula.
- Chemical formula of Petalite- LiAlSi 4O 10Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
- Chemical formula of Amethyst- SiO2
Petalite and Amethyst Specific Gravity
Another important criteria for qualitative analysis of gemstones is Petalite and Amethyst Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Petalite and Amethyst Optical Properties during the identification of gemstone. Specific gravity of Petalite is 2.65 whereas that of Amethyst is 2.65.