Kyanite and Goethite Physical Properties
Tenacity
Brittle
  
Not Available
  
Solubility
Not Available
  
HCl soluble
  
Durability
Not Available
  
Not Available
  
Specific Gravity
3.53-3.65
  
4.27-4.29
  
Fracture
Splintery, Brittle, Metallic
  
Uneven, torn surfaces, (e.g. fractured metals)., Uneven, Gemstones (2009), torn surfaces, (e.g. fractured metals).
  
Cleavage
[100] perfect [010] imperfect with 79° angle between
  
Perfect {010}
  
Mohs Hardness
4-7
  
5-5.5
  
Chemical Composition
Not Available
  
FeO(OH)Arthur Thomas , Gemstones (2009)
  
Kyanite and Goethite Chemical Formula
While comparing Kyanite and Goethite 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 Kyanite and Goethite chemical formula.
>- Chemical formula of Goethite- FeO(OH)Arthur Thomas , Gemstones (2009)
Kyanite and Goethite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Kyanite and Goethite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Kyanite and Goethite Optical Properties during the identification of gemstone. Specific gravity of Kyanite is 4.27-4.29 whereas that of Goethite is 4.27-4.29.