Keywords: Amfibol 2.jpg Mineral amphibole chemical composition Ca<sub>2</sub> Mg Fe <sub>4</sub>Al Si<sub>7</sub>Al O<sub>22</sub> OH F <sub>2</sub> from collection of National Museum Prague originally from Czech Republic Minerál amfibol ze sbírek Národního muzea původem z Čech own Karelj 2008-04-20 Amphibole Geological and mineralogical Exhibition NM Prague |