Opal and Rock Crystal Physical Properties

Opal and Rock Crystal Chemical Formula

While comparing Opal and Rock Crystal 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 Opal and Rock Crystal chemical formula.

• Chemical formula of Opal- SiO₂ · nH₂O
• Chemical formula of Rock Crystal- SiO 2Walter Schumann , Gemstones of the world (2001)

Opal and Rock Crystal Specific Gravity

Another important criteria for qualitative analysis of gemstones is Opal and Rock Crystal Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Opal and Rock Crystal Optical Properties during the identification of gemstone. Specific gravity of Opal is 2.65 whereas that of Rock Crystal is 2.65.