Londonite and Blue John Physical Properties

Londonite and Blue John Chemical Formula

While comparing Londonite and Blue John 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 Londonite and Blue John chemical formula.

• Chemical formula of Londonite- (Cs,K,Rb)Al 4Be 4(B,Be) 12O 28Anthony et al , Handbook of mineralogy (2001)
• Chemical formula of Blue John- CaF 2Michael O’Donoghue , Gems, Sixth Edition (2006)

Londonite and Blue John Specific Gravity

Another important criteria for qualitative analysis of gemstones is Londonite and Blue John Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Londonite and Blue John Optical Properties during the identification of gemstone. Specific gravity of Londonite is 3.00-3.25 whereas that of Blue John is 3.00-3.25.