Smoky Quartz and Opal Physical Properties
Tenacity
Brittle
  
BrittleWalter Schumann
  
Solubility
Not Available
  
hot salt water
  
Durability
Not Available
  
Not Available
  
Specific Gravity
2.65
  
1.98-2.25
  
Fracture
Conchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001)
  
Conchoidal, Conchoidal, Gemstones of the world (2001) More from other references, Brittle
  
Cleavage
{0110} Indistinct
  
None
  
Mohs Hardness
7
  
5-6.5
  
Chemical Composition
SiO2
  
SiO2 · nH2O
  
Smoky Quartz and Opal Chemical Formula
While comparing Smoky Quartz and 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 Smoky Quartz and Opal chemical formula.
- Chemical formula of Smoky Quartz- SiO2
- Chemical formula of Opal- SiO2 · nH2O
Smoky Quartz and Opal Specific Gravity
Another important criteria for qualitative analysis of gemstones is Smoky Quartz and Opal Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Smoky Quartz and Opal Optical Properties during the identification of gemstone. Specific gravity of Smoky Quartz is 1.98-2.25 whereas that of Opal is 1.98-2.25.