Metamorphosed granite-greisen-skarn assemblage and related tin mineralization in Nedvedice, Bohemian Massif

The Nedvedice orthogneiss is located in the Svratka Crystalline Complex, eastern part of the Kutna Hora Svratka Crystalline Unit, Bohemian Massif (Czech Republic). The orthogneiss is surrounded by a varied suite of rock types, such as mica schists, minor marbles, tourmalinites, amphibolites, serpentinites, quartzites and iron skarns. Its southeastern part is characterized by presence of tin mineralization, either associated with metapelites or in calc-silicate skarns, both in vicinity of the tourmaline-rich Nedvedice orthogneiss. Several tourmaline generations (magmatic, hydrothermal, metamorphic) were recorded in the tourmaline from the orthogneiss; together with metamorphic overprint of the tin mineralization in surrounding host rocks, the textures reflect Variscan metamorphic overprint of the Ordovician granite and its autochtonous (meta)sedimetary cover. The protolith of the Nedvedice orthogneiss is highly evolved, leucocratic, prealuminous granite rich in boron and fluorine.