Black Opal and Alunite Physical Properties

Black Opal and Alunite Chemical Formula

While comparing Black Opal 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 Black Opal and Alunite chemical formula.

• Chemical formula of Black Opal- SiO 2 + H 2OUlrich Henn and Claudio C.
• Chemical formula of Alunite- KAl3(SO4)2(OH)6

Black Opal and Alunite Specific Gravity

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