Keywords: Boulangerit 1.jpg Mineral boulangerite chemical composition Pb<sub>5</sub>Sb<sub>4</sub>S<sub>11</sub> from collection of National Museum Prague Czech Republic originally from Czech Republic Minerál boulangerit ze sbírek Národního muzea v Praze původem z Příbrami v Čechách own Karelj 2008-04-20 Boulangerite Geological and mineralogical Exhibition NM Prague |