Black Opal and Natrolite Physical Properties
Tenacity
Not Available
  
Brittle
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
1.97-2.22
  
2.20-2.26
  
Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
  
Uneven, Brittle, Metallic, Gemstones (2009)
  
Cleavage
Not Available
  
Perfect on {110}
  
Mohs Hardness
6-6.5
  
5-5.5
  
Chemical Composition
SiO 2 + H 2OUlrich Henn and Claudio C.
  
Na 2[Al 2Si 3O 10] · 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
  
Black Opal and Natrolite Chemical Formula
While comparing Black Opal and Natrolite 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 Black Opal and Natrolite chemical formula.
- Chemical formula of Black Opal- SiO 2 + H 2OUlrich Henn and Claudio C.
- Chemical formula of Natrolite- Na 2[Al 2Si 3O 10] · 2H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Black Opal and Natrolite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Black Opal and Natrolite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Black Opal and Natrolite Optical Properties during the identification of gemstone. Specific gravity of Black Opal is 2.20-2.26 whereas that of Natrolite is 2.20-2.26.