Goethite and Alunite Physical Properties

Goethite and Alunite Chemical Formula

While comparing Goethite and Alunite 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 Alunite chemical formula.

• Chemical formula of Goethite- FeO(OH)Arthur Thomas , Gemstones (2009)
• Chemical formula of Alunite- KAl3(SO4)2(OH)6

Goethite and Alunite Specific Gravity

Another important criteria for qualitative analysis of gemstones is Goethite and Alunite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Goethite and Alunite Optical Properties during the identification of gemstone. Specific gravity of Goethite is 2.6-2.9 whereas that of Alunite is 2.6-2.9.