Tourmaline and Black Opal Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.85-3.35
  
1.97-2.22
  
Fracture
Uneven, Conchoidal, ConchoidalArthur Thomas, Gemstones (2009)
  
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
  
Cleavage
Indistinct
  
Not Available
  
Mohs Hardness
7-7.5
  
6-6.5
  
Chemical Composition
Tourmaline is a series of several different minerals with unique chemical formulas. See The chemical formula of Tourmaline for details.
  
SiO 2 + H 2OUlrich Henn and Claudio C.
  
Tourmaline and Black Opal Chemical Formula
While comparing Tourmaline 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 Tourmaline and Black Opal chemical formula.
- Chemical formula of Tourmaline- Tourmaline is a series of several different minerals with unique chemical formulas. See The chemical formula of Tourmaline for details.
- Chemical formula of Black Opal- SiO 2 + H 2OUlrich Henn and Claudio C.
Tourmaline and Black Opal Specific Gravity
Another important criteria for qualitative analysis of gemstones is Tourmaline and Black Opal Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Tourmaline and Black Opal Optical Properties during the identification of gemstone. Specific gravity of Tourmaline is 1.97-2.22 whereas that of Black Opal is 1.97-2.22.