1) Monoclinic mineral 
Livingstonite is a mercury antimony sulfosalt mineral. It occurs in low-temperature hydrothermal veins associated with cinnabar, stibnite, sulfur and gypsum. It was first described in 1874 for an occurrence in Huitzuco de los Figueroa, Guerrero, Mexico. It was named to honor Scottish explorer of Africa, David Livingstone. ...