Biotite and Londonite Physical Properties

Biotite and Londonite Chemical Formula

While comparing Biotite and Londonite 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 Biotite and Londonite chemical formula.

• Chemical formula of Biotite- K(Mg,Fe++)3[AlSi3O10(OH,F)2
• Chemical formula of Londonite- (Cs,K,Rb)Al 4Be 4(B,Be) 12O 28Anthony et al , Handbook of mineralogy (2001)

Biotite and Londonite Specific Gravity

Another important criteria for qualitative analysis of gemstones is Biotite and Londonite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Biotite and Londonite Optical Properties during the identification of gemstone. Specific gravity of Biotite is 3.34 whereas that of Londonite is 3.34.