Moschellandsbergite
Moschellandsbergite is a rare isometric mineral made up of a silver-white amalgam of mercury and silver with the chemical makeup Ag2Hg3.
It was first described in 1938 and named after Moschellandsberg Mountain near Obermoschel, Rhineland-Palatinate, Germany. It is considered a low-temperature hydrothermal mineral which occurs with metacinnabar, cinnabar, mercurian silver, tetrahedrite–tennantite, pyrite, sphalerite and chalcopyrite.
