Mineral Species: Ternesite

Chemical Formula: Ca5(SiO4)2SO4

Chemical Name: Calcium Silicate

Mineral Class: Nesosilicate

Mineral Notes: Ternesite was only discoverd and approved as a valid mineral species in 1997. It is named after B. Ternes of Mayen, Germany, who found the mineral and provided specimens for study. The mineral forms in calcium-rich xenoliths in leucite tephrite lava found at Bellerberg, Eifel, Rheinland-Pflaz, Germany.

Description: A grey matrix in which is embedded a mass of pseudocrystalline pale-green Ternesite. When magnified the mineral shows some distinct crystal faces and a waxy luster. An interesting example of an extremely rare mineral.

Location: Bellerberg, Eifel, Rheinland-Pflaz, Germany (Type Location)