Goethite and Topaz Physical Properties
Tenacity
Not Available
  
Not Available
  
Solubility
HCl soluble
  
Not Available
  
Durability
Not Available
  
Not Available
  
Specific Gravity
4.27-4.29
  
3.49-3.57
  
Fracture
Uneven, torn surfaces, (e.g. fractured metals)., Uneven, Gemstones (2009), torn surfaces, (e.g. fractured metals).
  
Subconchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle
  
Cleavage
Perfect {010}
  
[001] Perfect
  
Mohs Hardness
5-5.5
  
8
  
Chemical Composition
FeO(OH)Arthur Thomas , Gemstones (2009)
  
Al2SiO4(F,OH)2
  
Goethite and Topaz Chemical Formula
While comparing Goethite and Topaz 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 Goethite and Topaz chemical formula.
- Chemical formula of Goethite- FeO(OH)Arthur Thomas , Gemstones (2009)
- Chemical formula of Topaz- Al2SiO4(F,OH)2
Goethite and Topaz Specific Gravity
Another important criteria for qualitative analysis of gemstones is Goethite and Topaz Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Goethite and Topaz Optical Properties during the identification of gemstone. Specific gravity of Goethite is 3.49-3.57 whereas that of Topaz is 3.49-3.57.