Willemite and Sapphire Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
insoluble
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.89-4.18
  
3.95-4.03
  
Fracture
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Uneven
  
Uneven, Uneven, Gems, Sixth Edition (2006)
  
Cleavage
{0001}, {11 2 0} imperfect
  
None, but may exhibit parting
  
Mohs Hardness
5.5
  
9
  
Chemical Composition
Zn 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
  
Al 2 O 3
  
Willemite and Sapphire Chemical Formula
While comparing Willemite and Sapphire 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 Willemite and Sapphire chemical formula.
- Chemical formula of Willemite- Zn 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
- Chemical formula of Sapphire- Al 2 O 3
Willemite and Sapphire Specific Gravity
Another important criteria for qualitative analysis of gemstones is Willemite and Sapphire Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Willemite and Sapphire Optical Properties during the identification of gemstone. Specific gravity of Willemite is 3.95-4.03 whereas that of Sapphire is 3.95-4.03.