Tourmaline and Alexandrite Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.85-3.35
  
3.69-3.81
  
Fracture
Uneven, Conchoidal, ConchoidalArthur Thomas, Gemstones (2009)
  
Not Available
  
Cleavage
Indistinct
  
1,1 ; 3,2.
  
Mohs Hardness
7-7.5
  
8.5
  
Chemical Composition
Tourmaline is a series of several different minerals with unique chemical formulas. See The chemical formula of Tourmaline for details.
  
BeAl 2 O 4
  
Tourmaline and Alexandrite Chemical Formula
While comparing Tourmaline and Alexandrite 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 Tourmaline and Alexandrite chemical formula.
- Chemical formula of Tourmaline- Tourmaline is a series of several different minerals with unique chemical formulas. See The chemical formula of Tourmaline for details.
- Chemical formula of Alexandrite- BeAl 2 O 4
Tourmaline and Alexandrite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Tourmaline and Alexandrite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Tourmaline and Alexandrite Optical Properties during the identification of gemstone. Specific gravity of Tourmaline is 3.69-3.81 whereas that of Alexandrite is 3.69-3.81.