Neptunite and Proustite Physical Properties
Tenacity
Brittle
  
Brittle
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.19-3.23
  
5.51-5.64
  
Fracture
Conchoidal, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle
  
Uneven, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle
  
Cleavage
{110} good
  
Distinct on {10 1 1}
  
Mohs Hardness
5-6
  
2.5
  
Chemical Composition
KNa 2Li(Fe2+ ,Mn2+ ) 2Ti 2Si 8O 24Michael OâDonoghue , Gems, Sixth Edition (2006)
  
Ag 3AsS 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
  
Neptunite and Proustite Chemical Formula
While comparing Neptunite and Proustite 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 Neptunite and Proustite chemical formula.
- Chemical formula of Neptunite- KNa 2Li(Fe2+ ,Mn2+ ) 2Ti 2Si 8O 24Michael OâDonoghue , Gems, Sixth Edition (2006)
- Chemical formula of Proustite- Ag 3AsS 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Neptunite and Proustite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Neptunite and Proustite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Neptunite and Proustite Optical Properties during the identification of gemstone. Specific gravity of Neptunite is 5.51-5.64 whereas that of Proustite is 5.51-5.64.