Petalite and Purpurite Physical Properties
Tenacity
Brittle
Not Available
Solubility
insoluble
Not Available
Durability
Not Available
Not Available
Specific Gravity
2.40
3.2-3.4
Fracture
Subconchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Conchoidal
Uneven, UnevenArthur Thomas, Gemstones (2009), Brittle
Cleavage
Perfect on {001}, poor on {201} with 38.5° angle between the two
[100] [001] perfect
Mohs Hardness
6-6.5
4-4.5
Chemical Composition
LiAlSi 4O 10Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
MnPO 4Walter Schumann , Gemstones of the world (2001) More from other references
Petalite and Purpurite Chemical Formula
While comparing Petalite and Purpurite 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 Purpurite chemical formula.
- Chemical formula of Petalite- LiAlSi 4O 10Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
- Chemical formula of Purpurite- MnPO 4Walter Schumann , Gemstones of the world (2001) More from other references
Petalite and Purpurite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Petalite and Purpurite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Petalite and Purpurite Optical Properties during the identification of gemstone. Specific gravity of Petalite is 3.2-3.4 whereas that of Purpurite is 3.2-3.4.