Astrophyllite and Gahnite Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
Not Available
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.2-3.4
  
4.00-4.62
  
Fracture
Uneven, Brittle, Metallic
  
Conchoidal, Uneven
  
Cleavage
Perfect on [001] imperfect on [100]
  
Indistinct parting on [111]
  
Mohs Hardness
3
  
7.5-8
  
Chemical Composition
(K,Na) 3(Fe2+ ,Mn) 7Ti 2Si 8O 24(O,OH) 7Anthony et al , Handbook of mineralogy (2001)
  
ZnAl 2O 4Michael OâDonoghue , Gems, Sixth Edition (2006)
  
Astrophyllite and Gahnite Chemical Formula
While comparing Astrophyllite and Gahnite 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 Astrophyllite and Gahnite chemical formula.
- Chemical formula of Astrophyllite- (K,Na) 3(Fe2+ ,Mn) 7Ti 2Si 8O 24(O,OH) 7Anthony et al , Handbook of mineralogy (2001)
- Chemical formula of Gahnite- ZnAl 2O 4Michael OâDonoghue , Gems, Sixth Edition (2006)
Astrophyllite and Gahnite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Astrophyllite and Gahnite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Astrophyllite and Gahnite Optical Properties during the identification of gemstone. Specific gravity of Astrophyllite is 4.00-4.62 whereas that of Gahnite is 4.00-4.62.