Opal and Rubellite Physical Properties
Tenacity
BrittleWalter Schumann
  
Not Available
  
Solubility
hot salt water
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
1.98-2.25
  
3.01-3.06
  
Fracture
Conchoidal, Conchoidal, Gemstones of the world (2001) More from other references, Brittle
  
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
  
Cleavage
None
  
Not Available
  
Mohs Hardness
5-6.5
  
7-7.5
  
Chemical Composition
SiO2 · nH2O
  
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.
  
Opal and Rubellite Chemical Formula
While comparing Opal and Rubellite 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 Opal and Rubellite chemical formula.
- Chemical formula of Opal- SiO2 · nH2O
- Chemical formula of Rubellite- 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.
Opal and Rubellite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Opal and Rubellite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Opal and Rubellite Optical Properties during the identification of gemstone. Specific gravity of Opal is 3.01-3.06 whereas that of Rubellite is 3.01-3.06.