Goethite and Ettringite Physical Properties
Tenacity
Not Available
Not Available
Solubility
HCl soluble
Partially soluble in water
Durability
Not Available
Not Available
Specific Gravity
4.27-4.29
1.77
Fracture
Uneven, torn surfaces, (e.g. fractured metals)., Uneven, Gemstones (2009), torn surfaces, (e.g. fractured metals).
Not Available
Cleavage
Perfect {010}
Perfect on {10 1 0}
Mohs Hardness
5-5.5
2-2.5
Chemical Composition
FeO(OH)Arthur Thomas , Gemstones (2009)
Ca 6Al 2(SO 4) 3(OH) 12 26H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)
Goethite and Ettringite Chemical Formula
While comparing Goethite and Ettringite 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 Ettringite chemical formula.
- Chemical formula of Goethite- FeO(OH)Arthur Thomas , Gemstones (2009)
- Chemical formula of Ettringite- Ca 6Al 2(SO 4) 3(OH) 12 26H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)
Goethite and Ettringite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Goethite and Ettringite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Goethite and Ettringite Optical Properties during the identification of gemstone. Specific gravity of Goethite is 1.77 whereas that of Ettringite is 1.77.