Spinel and Umbalite Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
none
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.64-3.66
  
3.62-4.33
  
Fracture
Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009)
  
Uneven, Uneven, ConchoidalGemdat.org, Management Team (2012)
  
Cleavage
None, but may exhibit slight parting
  
Not Available
  
Mohs Hardness
8
  
7-7.5
  
Chemical Composition
MgAl2O4
  
Mg 3Al 2(SiO 4) 3 -Mn2+3Al 2(SiO 4) 3Gemdat.org , Management Team (2012)
  
Spinel and Umbalite Chemical Formula
While comparing Spinel and Umbalite 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 Spinel and Umbalite chemical formula.
- Chemical formula of Spinel- MgAl2O4
- Chemical formula of Umbalite- Mg 3Al 2(SiO 4) 3 -Mn2+3Al 2(SiO 4) 3Gemdat.org , Management Team (2012)
Spinel and Umbalite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Spinel and Umbalite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Spinel and Umbalite Optical Properties during the identification of gemstone. Specific gravity of Spinel is 3.62-4.33 whereas that of Umbalite is 3.62-4.33.