Acta Musei Moraviae

Granitic pegmatites of the Bohemian Massif (Czech Republic); mineralogical, geochemical and regional classification and geological significance

Granitic pegmatites of the Bohemian Massif, Czech Republic were classified based on their geological position, chemical composition and mineralogy. The current classification (Černý 1991a) was modified due to a wide spectrum of examined pegmatitic rocks involving primitive pegmatites – coarse-grained leucosome with pegmatitic textures, highly evolved pegmatites – complex (Li) pegmatites with zoned internal structure as well as pegmatites contaminated from host rocks. The granitic pegmatites were discussed as members of their host regional units of the Bohemian Massif: Moldanubicum, Bohemicum, Saxothuringicum, Lugicum and Moravo-Silesian (Silesicurn, Brunovistulicum, Moravicum). The pegmatites of distinct classes: abyssal class (rare in the Moldanubicum and Saxothuringicum), muscovite-class (common in Silesicum), muscovite-rare-element class (common in Bohemicum), rare-element class (the most abundant, common in al! regional units) and miarolitic class (common in Lugicum, rare in Moldanubicum). The evident differences were found in chemical composition and mineralogy (activity of volatile components B, F and P, presence of Be-, Li- and REE-bearing minerals) and age (preVariscan – Bohemicum, Moravo-Silesian, Variscan – Moldanubicum, Saxothuringicum, Lugicum, Silesicum).