Nepheline and Black Opal Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.55-2.65
  
1.97-2.22
  
Fracture
Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
  
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
  
Cleavage
[1010] Poor
  
Not Available
  
Mohs Hardness
5-6
  
6-6.5
  
Chemical Composition
Na 3(Na,K)Al 4Si 4O 16Ulrich Henn and Claudio C.
  
SiO 2 + H 2OUlrich Henn and Claudio C.
  
Nepheline and Black Opal Chemical Formula
While comparing Nepheline and Black 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 Nepheline and Black Opal chemical formula.
- Chemical formula of Nepheline- Na 3(Na,K)Al 4Si 4O 16Ulrich Henn and Claudio C.
- Chemical formula of Black Opal- SiO 2 + H 2OUlrich Henn and Claudio C.
Nepheline and Black Opal Specific Gravity
Another important criteria for qualitative analysis of gemstones is Nepheline and Black Opal Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Nepheline and Black Opal Optical Properties during the identification of gemstone. Specific gravity of Nepheline is 1.97-2.22 whereas that of Black Opal is 1.97-2.22.