Verdelite and Sillimanite Physical Properties

Verdelite and Sillimanite Chemical Formula

While comparing Verdelite and Sillimanite 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 Verdelite and Sillimanite chemical formula.

• Chemical formula of Verdelite- Na(Li 1.5Al 1.5)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012) Formula given for elbaite.
• Chemical formula of Sillimanite- Al 2SiO 5Michael O’Donoghue , Gems, Sixth Edition (2006)

Verdelite and Sillimanite Specific Gravity

Another important criteria for qualitative analysis of gemstones is Verdelite and Sillimanite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Verdelite and Sillimanite Optical Properties during the identification of gemstone. Specific gravity of Verdelite is 3.20-3.26 whereas that of Sillimanite is 3.20-3.26.