Petalite and Cordierite Physical Properties
Tenacity
Brittle
  
Brittle
  
Solubility
insoluble
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.40
  
2.57-2.66
  
Fracture
Subconchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Conchoidal
  
Subconchoidal, Conchoidal, Brittle
  
Cleavage
Perfect on {001}, poor on {201} with 38.5° angle between the two
  
Fair on {100}, poor on {001} and {010}
  
Mohs Hardness
6-6.5
  
7-7.5
  
Chemical Composition
LiAlSi 4O 10Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
  
Mg2Al4Si5O18
  
Petalite and Cordierite Chemical Formula
While comparing Petalite and Cordierite 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 Cordierite chemical formula.
- Chemical formula of Petalite- LiAlSi 4O 10Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
- Chemical formula of Cordierite- Mg2Al4Si5O18
Petalite and Cordierite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Petalite and Cordierite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Petalite and Cordierite Optical Properties during the identification of gemstone. Specific gravity of Petalite is 2.57-2.66 whereas that of Cordierite is 2.57-2.66.