Crystal Opal and Coral Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
1.97-2.22
  
2.60-2.70
  
Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
  
Irregular, Irregular, Gemstones of the world (2001)
  
Cleavage
Not Available
  
Not Available
  
Mohs Hardness
5.5-6.5
  
3-4
  
Chemical Composition
SiO 2 + H 2OUlrich Henn and Claudio C.
  
CaCO 3Ulrich Henn and Claudio C.
  
Crystal Opal and Coral Chemical Formula
While comparing Crystal Opal and Coral 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 Crystal Opal and Coral chemical formula.
- Chemical formula of Crystal Opal- SiO 2 + H 2OUlrich Henn and Claudio C.
- Chemical formula of Coral- CaCO 3Ulrich Henn and Claudio C.
Crystal Opal and Coral Specific Gravity
Another important criteria for qualitative analysis of gemstones is Crystal Opal and Coral Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Crystal Opal and Coral Optical Properties during the identification of gemstone. Specific gravity of Crystal Opal is 2.60-2.70 whereas that of Coral is 2.60-2.70.