Willemite and Opal Physical Properties
Tenacity
Not Available
  
BrittleWalter Schumann
  
Solubility
Not Available
  
hot salt water
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.89-4.18
  
1.98-2.25
  
Fracture
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Uneven
  
Conchoidal, Conchoidal, Gemstones of the world (2001) More from other references, Brittle
  
Cleavage
{0001}, {11 2 0} imperfect
  
None
  
Mohs Hardness
5.5
  
5-6.5
  
Chemical Composition
Zn 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
  
SiO2 · nH2O
  
Willemite and Opal Chemical Formula
While comparing Willemite and Opal 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 Opal chemical formula.
- Chemical formula of Willemite- Zn 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
- Chemical formula of Opal- SiO2 · nH2O
Willemite and Opal Specific Gravity
Another important criteria for qualitative analysis of gemstones is Willemite and Opal Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Willemite and Opal Optical Properties during the identification of gemstone. Specific gravity of Willemite is 1.98-2.25 whereas that of Opal is 1.98-2.25.