Alexandrite and Achroite Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.69-3.81
  
2.90-3.40
  
Fracture
Not Available
  
Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001)
  
Cleavage
1,1 ; 3,2.
  
Not Available
  
Mohs Hardness
8.5
  
7-7.5
  
Chemical Composition
BeAl 2 O 4
  
Na(Li 1.5Al 1.5)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012) Formula given for elbaite.
  
Alexandrite and Achroite Chemical Formula
While comparing Alexandrite and Achroite 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 Alexandrite and Achroite chemical formula.
- Chemical formula of Alexandrite- BeAl 2 O 4
- Chemical formula of Achroite- Na(Li 1.5Al 1.5)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012) Formula given for elbaite.
Alexandrite and Achroite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Alexandrite and Achroite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Alexandrite and Achroite Optical Properties during the identification of gemstone. Specific gravity of Alexandrite is 2.90-3.40 whereas that of Achroite is 2.90-3.40.