Tortoiseshell and Norbergite Chemical Formula
While comparing Tortoiseshell and Norbergite 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 Tortoiseshell and Norbergite chemical formula.
>- Chemical formula of Norbergite- Mg 3(SiO 4)(F,OH) 2Anthony et al , Handbook of Mineralogy (2001)