Introduction Periodicals Bulletin mineralogicko-petrologického oddělení Národního muzea v Praze 2009/17/1 Mineralogie metamanganolitu z lokality Mísečky u Vernířovic (Česká republika)
Mineralogie metamanganolitu z lokality Mísečky u Vernířovic (Česká republika)
Pavel Novotný, Jiří Zimák
Two types of metamanganolite were found at the locality Mísečky near Vernířovice in the Hrubý Jeseník Mountains (northeastern part of the Bohemian Massif, the Czech Republic): (1) pinkish fine-grained quartz-garnet metamanganolite, and (2) grey-green chlorite-quartz-garnet metamanganolite, resembling a chloritized gneiss (so-called Desná gneis, widespread in the surroundings of Vernířovice). Manganese-rich garnet is a predominant component of both types of metamanganolite. The garnet shows a strong chemical zonality: manganese contents decrease rapidly from the core to rims in contrast to increasing iron contents. The first type of metamanganolite is known from many places in the surroundings of Vernířovice where quartzmagnetite iron ores of the BIF type were mined from the beginning of the 16th century until the beginning of the 19th century. The second type of metamanganolite is known only from the locality Mísečky and two other localities near Vernířovice. In the authors´ opinion, the apparent exceptionality of this metamanganolite type is due to its imperceptible appearence in terrain.