Alexandrite and Onyx Physical Properties

Alexandrite and Onyx Chemical Formula

While comparing Alexandrite and Onyx 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 Alexandrite and Onyx chemical formula.

• Chemical formula of Alexandrite- BeAl ₂ O ₄
• Chemical formula of Onyx- SiO₂

Alexandrite and Onyx Specific Gravity

Another important criteria for qualitative analysis of gemstones is Alexandrite and Onyx Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Alexandrite and Onyx Optical Properties during the identification of gemstone. Specific gravity of Alexandrite is 2.55-2.70 whereas that of Onyx is 2.55-2.70.