Abstract
The Bihar Mica Belt (BMB) -largest repository of muscovite in India, is located across the central part of Bihar State. Extending ENE-WSW for over 150 Km and having 20-40 Km width, BMB marks the eastern extremity of the Proterozoic Satpura Orogenic Belt of central India. Three groups of pegmatites recognised from this belt are: Gr. A or deformed pegmatite-characterized by deformed mineral grains-often foliated and are barren of commercial muscovite; Gr. B or muscovite pegmatite-typically zoned with quartz core and are the chief source of muscovite; Gr. C or rare metal pegmatite-free of deformation, characterized by dominance of K-feldspar over plagioclase, frequent presence of cleavelandite, lepidolite and muscovite.
Multigroup Discriminant Analysis using 6-element (viz. Na, K, Li, Rb, Ba and Pb; all in ppm) contents of K-feldspar from Gr.A, B and C pegmatites has been carried out. The two most influential discriminant axes (F1 and F2) together account for 99.7% of the total dispersion of the pooled data matrix. On the F1-F2 plane the projection of the samples forms separate clusters with little overlap. Furthermore the F1 axis alone accounts for c. 94% of the total dispersion and using only this function the three groups of pegmatites could be discrimmated.
